History of Climate Science Research
History of climate change interactive timeline.
The tables below contain all of the items that are in the timeline above, organized by category (greenhouse gases, modeling, past climate, impacts of climate change, and climate reports). If you have suggestions for additions to this timeline of the History of Climate Science Research , please contact us .
Greenhouse Gases and the Greenhouse Effect
Modeling the earth and future climate, studying past climate, the science of climate impacts, the intergovernmental panel on climate change (ipcc).
Climate Change: The IPCC 1990 and 1992 Assessments
Ipcc first assessment report overview and policymaker summaries and 1992 ipcc supplement . published with the support of australia, canada, germany, the netherlands, spain,united states of america, austria, france, japan, norway and united kingdom. printed in canada 178 pp..
Digitized by the Digitization and Microform Unit, UNOG Library, 2010
Cover (Front & Back)
Front matters, 1992 ipcc supplement, policymaker summary of working group i (scientific assessment of climate change), policymaker summary of working group ii (potential impacts of climate change), policymaker summary of working group iii (formulation of response strategies), policymaker summary of the ipcc special committee on the participation of developing countries.
A brief history of climate change
- Published 20 September 2013
BBC News environment correspondent Richard Black traces key milestones, scientific discoveries, technical innovations and political action.
1712 - British ironmonger Thomas Newcomen invents the first widely used steam engine, paving the way for the Industrial Revolution and industrial scale use of coal.
1800 - World population reaches one billion.
1824 - French physicist Joseph Fourier describes the Earth's natural "greenhouse effect". He writes: "The temperature [of the Earth] can be augmented by the interposition of the atmosphere, because heat in the state of light finds less resistance in penetrating the air, than in re-passing into the air when converted into non-luminous heat."
1861 - Irish physicist John Tyndall shows that water vapour and certain other gases create the greenhouse effect. "This aqueous vapour is a blanket more necessary to the vegetable life of England than clothing is to man," he concludes. More than a century later, he is honoured by having a prominent UK climate research organisation - the Tyndall Centre - named after him.
1886 - Karl Benz unveils the Motorwagen, often regarded as the first true automobile.
1896 - Swedish chemist Svante Arrhenius concludes that industrial-age coal burning will enhance the natural greenhouse effect. He suggests this might be beneficial for future generations. His conclusions on the likely size of the "man-made greenhouse" are in the same ballpark - a few degrees Celsius for a doubling of CO2 - as modern-day climate models.
1900 - Another Swede, Knut Angstrom, discovers that even at the tiny concentrations found in the atmosphere, CO2 strongly absorbs parts of the infrared spectrum. Although he does not realise the significance, Angstrom has shown that a trace gas can produce greenhouse warming.
1927 - Carbon emissions from fossil fuel burning and industry reach one billion tonnes per year.
1930 - Human population reaches two billion.
1938 - Using records from 147 weather stations around the world, British engineer Guy Callendar shows that temperatures had risen over the previous century. He also shows that CO2 concentrations had increased over the same period, and suggests this caused the warming. The "Callendar effect" is widely dismissed by meteorologists.
1955 - Using a new generation of equipment including early computers, US researcher Gilbert Plass analyses in detail the infrared absorption of various gases. He concludes that doubling CO2 concentrations would increase temperatures by 3-4C.
1957 - US oceanographer Roger Revelle and chemist Hans Suess show that seawater will not absorb all the additional CO2 entering the atmosphere, as many had assumed. Revelle writes: "Human beings are now carrying out a large scale geophysical experiment..."
1958 - Using equipment he had developed himself, Charles David (Dave) Keeling begins systematic measurements of atmospheric CO2 at Mauna Loa in Hawaii and in Antarctica. Within four years, the project - which continues today - provides the first unequivocal proof that CO2 concentrations are rising.
1960 - Human population reaches three billion.
1965 - A US President's Advisory Committee panel warns that the greenhouse effect is a matter of "real concern".
1972 - First UN environment conference, in Stockholm. Climate change hardly registers on the agenda, which centres on issues such as chemical pollution, atomic bomb testing and whaling. The United Nations Environment Programme (Unep) is formed as a result.
1975 - Human population reaches four billion.
1975 - US scientist Wallace Broecker puts the term "global warming" into the public domain in the title of a scientific paper.
1987 - Human population reaches five billion
1987 - Montreal Protocol agreed, restricting chemicals that damage the ozone layer. Although not established with climate change in mind, it has had a greater impact on greenhouse gas emissions than the Kyoto Protocol.
1988 - Intergovernmental Panel on Climate Change (IPCC) formed to collate and assess evidence on climate change.
1989 - UK Prime Minister Margaret Thatcher - possessor of a chemistry degree - warns in a speech to the UN that "We are seeing a vast increase in the amount of carbon dioxide reaching the atmosphere... The result is that change in future is likely to be more fundamental and more widespread than anything we have known hitherto." She calls for a global treaty on climate change.
1989 - Carbon emissions from fossil fuel burning and industry reach six billion tonnes per year.
1990 - IPCC produces First Assessment Report. It concludes that temperatures have risen by 0.3-0.6C over the last century, that humanity's emissions are adding to the atmosphere's natural complement of greenhouse gases, and that the addition would be expected to result in warming.
1992 - At the Earth Summit in Rio de Janeiro, governments agree the United Framework Convention on Climate Change. Its key objective is "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system". Developed countries agree to return their emissions to 1990 levels.
1995 - IPCC Second Assessment Report concludes that the balance of evidence suggests "a discernible human influence" on the Earth's climate. This has been called the first definitive statement that humans are responsible for climate change.
1997 - Kyoto Protocol agreed. Developed nations pledge to reduce emissions by an average of 5% by the period 2008-12, with wide variations on targets for individual countries. US Senate immediately declares it will not ratify the treaty.
1998 - Strong El Nino conditions combine with global warming to produce the warmest year on record. The average global temperature reached 0.52C above the mean for the period 1961-90 (a commonly used baseline).
1998 - Publication of the controversial "hockey stick" graph indicating that modern-day temperature rise in the northern hemisphere is unusual compared with the last 1,000 years. The work would later be the subject of two enquiries instigated by the US Congress.
1999 - Human population reaches six billion.
2001 - President George W Bush removes the US from the Kyoto process.
2001 - IPCC Third Assessment Report finds "new and stronger evidence" that humanity's emissions of greenhouse gases are the main cause of the warming seen in the second half of the 20th Century.
2005 - The Kyoto Protocol becomes international law for those countries still inside it.
2005 - UK Prime Minister Tony Blair selects climate change as a priority for his terms as chair of the G8 and president of the EU.
2006 - The Stern Review concludes that climate change could damage global GDP by up to 20% if left unchecked - but curbing it would cost about 1% of global GDP.
2006 - Carbon emissions from fossil fuel burning and industry reach eight billion tonnes per year.
2007 - The IPCC's Fourth Assessment Report concludes it is more than 90% likely that humanity's emissions of greenhouse gases are responsible for modern-day climate change.
2007 - The IPCC and former US vice-president Al Gore receive the Nobel Peace Prize "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change".
2007 - At UN negotiations in Bali, governments agree the two-year "Bali roadmap" aimed at hammering out a new global treaty by the end of 2009.
2008 - Half a century after beginning observations at Mauna Loa, the Keeling project shows that CO2 concentrations have risen from 315 parts per million (ppm) in 1958 to 380ppm in 2008.
2008 - Two months before taking office, incoming US president Barack Obama pledges to "engage vigorously" with the rest of the world on climate change.
2009 - China overtakes the US as the world's biggest greenhouse gas emitter - although the US remains well ahead on a per-capita basis.
2009 - Computer hackers download a huge tranche of emails from a server at the University of East Anglia's Climatic Research Unit and release some on the internet, leading to the "ClimateGate" affair.
2009 - 192 governments convene for the UN climate summit in Copenhagen with expectations of a new global agreement high; but they leave only with a controversial political declaration, the Copenhagen Accord.
2010 - Developed countries begin contributing to a $30bn, three-year deal on "Fast Start Finance" to help them "green" their economies and adapt to climate impacts.
2010 - A series of reviews into "ClimateGate" and the IPCC ask for more openness, but clear scientists of malpractice.
2010 - The UN summit in Mexico does not collapse, as had been feared, but ends with agreements on a number of issues.
2011 - A new analysis of the Earth's temperature record by scientists concerned over the "ClimateGate" allegations proves the planet's land surface really has warmed over the last century.
2011 - Human population reaches seven billion.
2011 - Data shows concentrations of greenhouse gases are rising faster than in previous years.
2012 - Arctic sea ice reaches a minimum extent of 3.41 million sq km (1.32 million sq mi), a record for the lowest summer cover since satellite measurements began in 1979.
2013 - The Mauna Loa Observatory on Hawaii reports that the daily mean concentration of CO2 in the atmosphere has surpassed 400 parts per million (ppm) for the first time since measurements began in 1958.
2013 - The first part of the IPCC's fifth assessment report says scientists are 95% certain that humans are the "dominant cause" of global warming since the 1950s.
Related Internet Links
UN climate convention
1992 World Scientists' Warning to Humanity
Published Jul 16, 1992 Updated Feb 4, 2022
UCS is maintaining this page as part of our history. However, we understand that elements of this letter are deeply problematic. Specifically, centering population—with only a cursory nod to the consumption of wealthy nations and the wealthiest people—is a narrative rooted in colonialism and racism, and current-day unjust and inequitable socioeconomic systems.
For a more in-depth discussion, please read our explainers on climate change and population , and food security and population .
Some 1,700 of the world's leading scientists, including the majority of Nobel laureates in the sciences, issued this appeal in November 1992. The World Scientists' Warning to Humanity was written and spearheaded by the late Henry Kendall, former chair of UCS's board of directors.
Introduction
Human beings and the natural world are on a collision course. Human activities inflict harsh and often irreversible damage on the environment and on critical resources. If not checked, many of our current practices put at serious risk the future that we wish for human society and the plant and animal kingdoms, and may so alter the living world that it will be unable to sustain life in the manner that we know. Fundamental changes are urgent if we are to avoid the collision our present course will bring about.
The environment
The environment is suffering critical stress:
The atmosphere
Stratospheric ozone depletion threatens us with enhanced ultraviolet radiation at the earth's surface, which can be damaging or lethal to many life forms. Air pollution near ground level, and acid precipitation, are already causing widespread injury to humans, forests, and crops.
Water resources
Heedless exploitation of depletable ground water supplies endangers food production and other essential human systems. Heavy demands on the world's surface waters have resulted in serious shortages in some 80 countries, containing 40 percent of the world's population. Pollution of rivers, lakes, and ground water further limits the supply.
Destructive pressure on the oceans is severe, particularly in the coastal regions which produce most of the world's food fish. The total marine catch is now at or above the estimated maximum sustainable yield. Some fisheries have already shown signs of collapse. Rivers carrying heavy burdens of eroded soil into the seas also carry industrial, municipal, agricultural, and livestock waste—some of it toxic.
Loss of soil productivity, which is causing extensive land abandonment, is a widespread by-product of current practices in agriculture and animal husbandry. Since 1945, 11 percent of the earth's vegetated surface has been degraded—an area larger than India and China combined—and per capita food production in many parts of the world is decreasing.
Tropical rain forests, as well as tropical and temperate dry forests, are being destroyed rapidly. At present rates, some critical forest types will be gone in a few years, and most of the tropical rain forest will be gone before the end of the next century. With them will go large numbers of plant and animal species.
Living species
The irreversible loss of species, which by 2100 may reach one-third of all species now living, is especially serious. We are losing the potential they hold for providing medicinal and other benefits, and the contribution that genetic diversity of life forms gives to the robustness of the world's biological systems and to the astonishing beauty of the earth itself.
Much of this damage is irreversible on a scale of centuries, or permanent. Other processes appear to pose additional threats. Increasing levels of gases in the atmosphere from human activities, including carbon dioxide released from fossil fuel burning and from deforestation, may alter climate on a global scale. Predictions of global warming are still uncertain—with projected effects ranging from tolerable to very severe—but the potential risks are very great.
Our massive tampering with the world's interdependent web of life—coupled with the environmental damage inflicted by deforestation, species loss, and climate change—could trigger widespread adverse effects, including unpredictable collapses of critical biological systems whose interactions and dynamics we only imperfectly understand.
Uncertainty over the extent of these effects cannot excuse complacency or delay in facing the threats.
The earth is finite. Its ability to absorb wastes and destructive effluent is finite. Its ability to provide food and energy is finite. Its ability to provide for growing numbers of people is finite. And we are fast approaching many of the earth's limits. Current economic practices which damage the environment, in both developed and underdeveloped nations, cannot be continued without the risk that vital global systems will be damaged beyond repair.
Pressures resulting from unrestrained population growth put demands on the natural world that can overwhelm any efforts to achieve a sustainable future. If we are to halt the destruction of our environment, we must accept limits to that growth. A World Bank estimate indicates that world population will not stabilize at less than 12.4 billion, while the United Nations concludes that the eventual total could reach 14 billion, a near tripling of today's 5.4 billion. But, even at this moment, one person in five lives in absolute poverty without enough to eat, and one in ten suffers serious malnutrition.
No more than one or a few decades remain before the chance to avert the threats we now confront will be lost and the prospects for humanity immeasurably diminished.
We the undersigned, senior members of the world's scientific community, hereby warn all humanity of what lies ahead. A great change in our stewardship of the earth and the life on it is required, if vast human misery is to be avoided and our global home on this planet is not to be irretrievably mutilated.
What we must do
Five inextricably linked areas must be addressed simultaneously:
We must bring environmentally damaging activities under control to restore and protect the integrity of the earth's systems we depend on.
We must, for example, move away from fossil fuels to more benign, inexhaustible energy sources to cut greenhouse gas emissions and the pollution of our air and water. Priority must be given to the development of energy sources matched to Third World needs—small-scale and relatively easy to implement.
We must halt deforestation, injury to and loss of agricultural land, and the loss of terrestrial and marine plant and animal species.
We must manage resources crucial to human welfare more effectively.
We must give high priority to efficient use of energy, water, and other materials, including expansion of conservation and recycling.
We must stabilize population.
This will be possible only if all nations recognize that it requires improved social and economic conditions, and the adoption of effective, voluntary family planning.
We must reduce and eventually eliminate poverty.
We must ensure sexual equality, and guarantee women control over their own reproductive decisions., developed nations must act now.
The developed nations are the largest polluters in the world today. They must greatly reduce their overconsumption, if we are to reduce pressures on resources and the global environment. The developed nations have the obligation to provide aid and support to developing nations, because only the developed nations have the financial resources and the technical skills for these tasks.
Acting on this recognition is not altruism, but enlightened self-interest: whether industrialized or not, we all have but one lifeboat. No nation can escape from injury when global biological systems are damaged. No nation can escape from conflicts over increasingly scarce resources. In addition, environmental and economic instabilities will cause mass migrations with incalculable consequences for developed and undeveloped nations alike.
Developing nations must realize that environmental damage is one of the gravest threats they face, and that attempts to blunt it will be overwhelmed if their populations go unchecked. The greatest peril is to become trapped in spirals of environmental decline, poverty, and unrest, leading to social, economic, and environmental collapse.
Success in this global endeavor will require a great reduction in violence and war. Resources now devoted to the preparation and conduct of war—amounting to over $1 trillion annually—will be badly needed in the new tasks and should be diverted to the new challenges.
A new ethic is required—a new attitude towards discharging our responsibility for caring for ourselves and for the earth. We must recognize the earth's limited capacity to provide for us. We must recognize its fragility. We must no longer allow it to be ravaged. This ethic must motivate a great movement, convincing reluctant leaders and reluctant governments and reluctant peoples themselves to effect the needed changes.
The scientists issuing this warning hope that our message will reach and affect people everywhere. We need the help of many.
- We require the help of the world community of scientists—natural, social, economic, and political.
- We require the help of the world's business and industrial leaders.
- We require the help of the world's religious leaders.
- We require the help of the world's peoples.
We call on all to join us in this task.
Related resources.
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Getting Science Back on Track
Federal Scientists Survey 2023
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Yale Climate Connections
Scientists agree: Climate change is real and caused by people
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The scientific consensus that climate change is happening and that it is human-caused is strong. Scientific investigation of global warming began in the 19th century , and by the early 2000s, this research began to coalesce into confidence about the reality, causes, and general range of adverse effects of global warming. This conclusion was drawn from studying air and ocean temperatures, the atmosphere’s composition, satellite records, ice cores, modeling, and more.
In 1988 the United Nations and World Meteorological Organization founded the Intergovernmental Panel on Climate Change, IPCC, to provide regular updates on the scientific evidence on global warming. In a 2013 report , the IPCC concluded that scientific evidence of warming is “unequivocal” and that the largest cause is an increase of carbon dioxide in the atmosphere as a result of humans burning fossil fuels. The IPCC continues to assess this science, periodically issuing new reports.
Climate change is real and caused by humans
The IPCC is not the only scientific group that has reached a clear consensus on the scientific evidence of human-caused global warming. As this NASA page points out, 200 global scientific organizations, 11 international science academies, and 18 American science associations have released statements in alignment with this consensus.
Amanda Staudt is the senior director for climate, atmospheric and polar sciences at the National Academies of Science, Engineering and Medicine, where she has worked since 2001. The Academies, she said, first began studying climate change in 1979, researching how much warming would likely happen if the amount of carbon dioxide concentrations in the atmosphere were doubled.
Four decades later, those findings have held up and have been strengthened based on scores of continued studies and analysis. “The remarkable thing about that study,” she said, “is that they basically got the right answer” from the start. This 1979 study by the National Research Council, Staudt said, led to investment in climate science in the U.S.
Though this consensus has been thoroughly established, scientific research and new findings continue. Staudt said countless attempted rebuttals of climate science findings have been researched and disproved.
“We did a lot of studies in that time period, looking at those questions,” she said, ”and one by one, putting them to bed and convincing ourselves over and over again, that humans were affecting climate, and that we could document that effect.”
At the National Academies, reaching consensus requires open sessions and dialogue with scientists and agreement from committees, which typically consist of 12-15 experts. Their draft reports go through peer review, and reviewers’ concerns are resolved before publication is approved. The goal is for the complex science of climate change to become as thoroughly researched and substantiated as possible.
“One of the things I think about scientists is that we’re all inherently skeptics at some level,” Staudt said. “That’s what drives us to science, that we have questions about the world around us. And we want to prove that for ourselves.”
Scientists consistently reaffirm evidence that climate change is happening
Climate scientists worldwide go through similar processes before their findings are published. And their research papers, too, show a strong consensus about global warming. As NASA states on its website , “Multiple studies published in peer-reviewed scientific journals show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities.” (By sound practice, scientists resist saying science is for all times “certain” or that its findings are “final,” and the “extremely likely” language respects that practice.)
One of the studies about the consensus was led by John Cook, a fellow at the Climate Change Communication Research Hub at Monash University in Melbourne, Australia. Cook and colleagues reviewed nearly 12,000 scientific papers to examine how aligned published research is on major findings on climate change. That study found that 97 percent of scholarly papers that take a position on climate change do endorse the consensus. The papers that rejected the consensus position contained errors, according to subsequent research .
In reviewing the papers, Cook has said he and his colleagues found the consensus to have been so widely accepted by 2013 that many researchers by then no longer felt a need to mention or reaffirm it in their research papers.
Also see: Causes of global warming: How scientists know that humans are responsible
Samantha Harrington
Samantha Harrington, director of audience experience for Yale Climate Connections, is a journalist and graphic designer with a background in digital media and entrepreneurship. Sam is especially interested... More by Samantha Harrington
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Science News
How did we get here the roots and impacts of the climate crisis, people’s heavy reliance on fossil fuels and the cutting down of carbon-storing forests have transformed global climate..
For more than a century, researchers have honed their methods for measuring the impacts of human actions on Earth's atmosphere.
Sam Falconer
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By Alexandra Witze
March 10, 2022 at 11:00 am
Even in a world increasingly battered by weather extremes, the summer 2021 heat wave in the Pacific Northwest stood out. For several days in late June, cities such as Vancouver, Portland and Seattle baked in record temperatures that killed hundreds of people. On June 29, Lytton, a village in British Columbia, set an all-time heat record for Canada, at 121° Fahrenheit (49.6° Celsius); the next day, the village was incinerated by a wildfire.
Within a week, an international group of scientists had analyzed this extreme heat and concluded it would have been virtually impossible without climate change caused by humans. The planet’s average surface temperature has risen by at least 1.1 degrees Celsius since preindustrial levels of 1850–1900. The reason: People are loading the atmosphere with heat-trapping gases produced during the burning of fossil fuels, such as coal and gas, and from cutting down forests.
To celebrate our 100th anniversary, we’re highlighting some of the biggest advances in science over the last century. To see more from the series, visit Century of Science .
A little over 1 degree of warming may not sound like a lot. But it has already been enough to fundamentally transform how energy flows around the planet. The pace of change is accelerating, and the consequences are everywhere. Ice sheets in Greenland and Antarctica are melting, raising sea levels and flooding low-lying island nations and coastal cities. Drought is parching farmlands and the rivers that feed them. Wildfires are raging. Rains are becoming more intense, and weather patterns are shifting .
The roots of understanding this climate emergency trace back more than a century and a half. But it wasn’t until the 1950s that scientists began the detailed measurements of atmospheric carbon dioxide that would prove how much carbon is pouring from human activities. Beginning in the 1960s, researchers started developing comprehensive computer models that now illuminate the severity of the changes ahead.
Today we know that climate change and its consequences are real, and we are responsible. The emissions that people have been putting into the air for centuries — the emissions that made long-distance travel, economic growth and our material lives possible — have put us squarely on a warming trajectory . Only drastic cuts in carbon emissions, backed by collective global will, can make a significant difference.
“What’s happening to the planet is not routine,” says Ralph Keeling, a geochemist at the Scripps Institution of Oceanography in La Jolla, Calif. “We’re in a planetary crisis.”
Setting the stage
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One day in the 1850s, Eunice Newton Foote, an amateur scientist and a women’s rights activist living in upstate New York, put two glass jars in sunlight. One contained regular air — a mix of nitrogen, oxygen and other gases including carbon dioxide — while the other contained just carbon dioxide. Both had thermometers in them. As the sun’s rays beat down, Foote observed that the jar of CO 2 alone heated up more quickly, and was slower to cool down, than the one containing plain air.
The results prompted Foote to muse on the relationship between CO 2 , the planet and heat. “An atmosphere of that gas would give to our earth a high temperature,” she wrote in an 1856 paper summarizing her findings .
Three years later, working independently and apparently unaware of Foote’s discovery, Irish physicist John Tyndall showed the same basic idea in more detail. With a set of pipes and devices to study the transmission of heat, he found that CO 2 gas, as well as water vapor, absorbed more heat than air alone. He argued that such gases would trap heat in Earth’s atmosphere, much as panes of glass trap heat in a greenhouse, and thus modulate climate.
Today Tyndall is widely credited with the discovery of how what we now call greenhouse gases heat the planet, earning him a prominent place in the history of climate science. Foote faded into relative obscurity — partly because of her gender, partly because her measurements were less sensitive. Yet their findings helped kick off broader scientific exploration of how the composition of gases in Earth’s atmosphere affects global temperatures.
Heat-trapping gases
In 1859, John Tyndall used this apparatus to study how various gases trap heat. He sent infrared radiation through a tube filled with gas and measured the resulting temperature changes. Carbon dioxide and water vapor, he showed, absorb more heat than air does.
Carbon floods in
Humans began substantially affecting the atmosphere around the turn of the 19th century, when the Industrial Revolution took off in Britain. Factories burned tons of coal; fueled by fossil fuels, the steam engine revolutionized transportation and other industries. Since then, fossil fuels including oil and natural gas have been harnessed to drive a global economy. All these activities belch gases into the air.
Yet Swedish physical chemist Svante Arrhenius wasn’t worried about the Industrial Revolution when he began thinking in the late 1800s about changes in atmospheric CO 2 levels. He was instead curious about ice ages — including whether a decrease in volcanic eruptions, which can put carbon dioxide into the atmosphere, would lead to a future ice age. Bored and lonely in the wake of a divorce, Arrhenius set himself to months of laborious calculations involving moisture and heat transport in the atmosphere at different zones of latitude. In 1896, he reported that halving the amount of CO 2 in the atmosphere could indeed bring about an ice age — and that doubling CO 2 would raise global temperatures by around 5 to 6 degrees C.
It was a remarkably prescient finding for work that, out of necessity, had simplified Earth’s complex climate system down to just a few variables. But Arrhenius’ findings didn’t gain much traction with other scientists at the time. The climate system seemed too large, complex and inert to change in any meaningful way on a timescale that would be relevant to human society. Geologic evidence showed, for instance, that ice ages took thousands of years to start and end. What was there to worry about?
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One researcher, though, thought the idea was worth pursuing. Guy Stewart Callendar, a British engineer and amateur meteorologist, had tallied weather records over time, obsessively enough to determine that average temperatures were increasing at 147 weather stations around the globe. In a 1938 paper in a Royal Meteorological Society journal, he linked this temperature rise to the burning of fossil fuels . Callendar estimated that fossil fuel burning had put around 150 billion metric tons of CO 2 into the atmosphere since the late 19th century.
Like many of his day, Callendar didn’t see global warming as a problem. Extra CO 2 would surely stimulate plants to grow and allow crops to be farmed in new regions. “In any case the return of the deadly glaciers should be delayed indefinitely,” he wrote. But his work revived discussions tracing back to Tyndall and Arrhenius about how the planetary system responds to changing levels of gases in the atmosphere. And it began steering the conversation toward how human activities might drive those changes.
When World War II broke out the following year, the global conflict redrew the landscape for scientific research. Hugely important wartime technologies, such as radar and the atomic bomb, set the stage for “big science” studies that brought nations together to tackle high-stakes questions of global reach. And that allowed modern climate science to emerge.
The Keeling curve
One major effort was the International Geophysical Year, or IGY, an 18-month push in 1957–1958 that involved a wide array of scientific field campaigns including exploration in the Arctic and Antarctica. Climate change wasn’t a high research priority during the IGY, but some scientists in California, led by Roger Revelle of the Scripps Institution of Oceanography, used the funding influx to begin a project they’d long wanted to do. The goal was to measure CO 2 levels at different locations around the world, accurately and consistently.
The job fell to geochemist Charles David Keeling, who put ultraprecise CO 2 monitors in Antarctica and on the Hawaiian volcano of Mauna Loa. Funds soon ran out to maintain the Antarctic record, but the Mauna Loa measurements continued. Thus was born one of the most iconic datasets in all of science — the “Keeling curve,” which tracks the rise of atmospheric CO 2 .
When Keeling began his measurements in 1958, CO 2 made up 315 parts per million of the global atmosphere. Within just a few years it became clear that the number was increasing year by year. Because plants take up CO 2 as they grow in spring and summer and release it as they decompose in fall and winter, CO 2 concentrations rose and fell each year in a sawtooth pattern. But superimposed on that pattern was a steady march upward.
“The graph got flashed all over the place — it was just such a striking image,” says Ralph Keeling, who is Keeling’s son. Over the years, as the curve marched higher, “it had a really important role historically in waking people up to the problem of climate change.” The Keeling curve has been featured in countless earth science textbooks, congressional hearings and in Al Gore’s 2006 documentary on climate change, An Inconvenient Truth .
Each year the curve keeps going up: In 2016, it passed 400 ppm of CO 2 in the atmosphere as measured during its typical annual minimum in September. Today it is at 413 ppm. (Before the Industrial Revolution, CO 2 levels in the atmosphere had been stable for centuries at around 280 ppm.)
Around the time that Keeling’s measurements were kicking off, Revelle also helped develop an important argument that the CO 2 from human activities was building up in Earth’s atmosphere. In 1957, he and Hans Suess, also at Scripps at the time, published a paper that traced the flow of radioactive carbon through the oceans and the atmosphere . They showed that the oceans were not capable of taking up as much CO 2 as previously thought; the implication was that much of the gas must be going into the atmosphere instead.
Steady rise
Known as the Keeling curve, this chart shows the rise in CO 2 levels as measured at the Mauna Loa Observatory in Hawaii due to human activities. The visible sawtooth pattern is due to seasonal plant growth: Plants take up CO 2 in the growing seasons, then release it as they decompose in fall and winter.
Monthly average CO 2 concentrations at Mauna Loa Observatory
“Human beings are now carrying out a large-scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future,” Revelle and Suess wrote in the paper. It’s one of the most famous sentences in earth science history.
Here was the insight underlying modern climate science: Atmospheric carbon dioxide is increasing, and humans are causing the buildup. Revelle and Suess became the final piece in a puzzle dating back to Svante Arrhenius and John Tyndall. “I tell my students that to understand the basics of climate change, you need to have the cutting-edge science of the 1860s, the cutting-edge math of the 1890s and the cutting-edge chemistry of the 1950s,” says Joshua Howe, an environmental historian at Reed College in Portland, Ore.
Evidence piles up
Observational data collected throughout the second half of the 20th century helped researchers gradually build their understanding of how human activities were transforming the planet.
Ice cores pulled from ice sheets, such as that atop Greenland, offer some of the most telling insights for understanding past climate change. Each year, snow falls atop the ice and compresses into a fresh layer of ice representing climate conditions at the time it formed. The abundance of certain forms, or isotopes, of oxygen and hydrogen in the ice allows scientists to calculate the temperature at which it formed, and air bubbles trapped within the ice reveal how much carbon dioxide and other greenhouse gases were in the atmosphere at that time. So drilling down into an ice sheet is like reading the pages of a history book that go back in time the deeper you go.
Scientists began reading these pages in the early 1960s, using ice cores drilled at a U.S. military base in northwest Greenland . Contrary to expectations that past climates were stable, the cores hinted that abrupt climate shifts had happened over the last 100,000 years. By 1979, an international group of researchers was pulling another deep ice core from a second location in Greenland — and it, too, showed that abrupt climate change had occurred in the past. In the late 1980s and early 1990s, a pair of European- and U.S.-led drilling projects retrieved even deeper cores from near the top of the ice sheet, pushing the record of past temperatures back a quarter of a million years.
Together with other sources of information, such as sediment cores drilled from the seafloor and molecules preserved in ancient rocks, the ice cores allowed scientists to reconstruct past temperature changes in extraordinary detail. Many of those changes happened alarmingly fast. For instance, the climate in Greenland warmed abruptly more than 20 times in the last 80,000 years , with the changes occurring in a matter of decades. More recently, a cold spell that set in around 13,000 years ago suddenly came to an end around 11,500 years ago — and temperatures in Greenland rose 10 degrees C in a decade.
Evidence for such dramatic climate shifts laid to rest any lingering ideas that global climate change would be slow and unlikely to occur on a timescale that humans should worry about. “It’s an important reminder of how ‘tippy’ things can be,” says Jessica Tierney, a paleoclimatologist at the University of Arizona in Tucson.
More evidence of global change came from Earth-observing satellites, which brought a new planet-wide perspective on global warming beginning in the 1960s. From their viewpoint in the sky, satellites have measured the rise in global sea level — currently 3.4 millimeters per year and accelerating, as warming water expands and as ice sheets melt — as well as the rapid decline in ice left floating on the Arctic Ocean each summer at the end of the melt season. Gravity-sensing satellites have “weighed” the Antarctic and Greenlandic ice sheets from above since 2002, reporting that more than 400 billion metric tons of ice are lost each year.
Temperature observations taken at weather stations around the world also confirm that we are living in the hottest years on record. The 10 warmest years since record keeping began in 1880 have all occurred since 2005 . And nine of those 10 have come since 2010.
Worrisome predictions
By the 1960s, there was no denying that the planet was warming. But understanding the consequences of those changes — including the threat to human health and well-being — would require more than observational data. Looking to the future depended on computer simulations: complex calculations of how energy flows through the planetary system.
A first step in building such climate models was to connect everyday observations of weather to the concept of forecasting future climate. During World War I, British mathematician Lewis Fry Richardson imagined tens of thousands of meteorologists, each calculating conditions for a small part of the atmosphere but collectively piecing together a global forecast.
But it wasn’t until after World War II that computational power turned Richardson’s dream into reality. In the wake of the Allied victory, which relied on accurate weather forecasts for everything from planning D-Day to figuring out when and where to drop the atomic bombs, leading U.S. mathematicians acquired funding from the federal government to improve predictions. In 1950, a team led by Jule Charney, a meteorologist at the Institute for Advanced Study in Princeton, N.J., used the ENIAC, the first U.S. programmable, electronic computer, to produce the first computer-driven regional weather forecast . The forecasting was slow and rudimentary, but it built on Richardson’s ideas of dividing the atmosphere into squares, or cells, and computing the weather for each of those. The work set the stage for decades of climate modeling to follow.
By 1956, Norman Phillips, a member of Charney’s team, had produced the world’s first general circulation model, which captured how energy flows between the oceans, atmosphere and land. The field of climate modeling was born.
The work was basic at first because early computers simply didn’t have much computational power to simulate all aspects of the planetary system.
An important breakthrough came in 1967, when meteorologists Syukuro Manabe and Richard Wetherald — both at the Geophysical Fluid Dynamics Laboratory in Princeton, a lab born from Charney’s group — published a paper in the Journal of the Atmospheric Sciences that modeled connections between Earth’s surface and atmosphere and calculated how changes in CO 2 would affect the planet’s temperature. Manabe and Wetherald were the first to build a computer model that captured the relevant processes that drive climate , and to accurately simulate how the Earth responds to those processes.
The rise of climate modeling allowed scientists to more accurately envision the impacts of global warming. In 1979, Charney and other experts met in Woods Hole, Mass., to try to put together a scientific consensus on what increasing levels of CO 2 would mean for the planet. The resulting “Charney report” concluded that rising CO 2 in the atmosphere would lead to additional and significant climate change.
In the decades since, climate modeling has gotten increasingly sophisticated . And as climate science firmed up, climate change became a political issue.
The hockey stick
This famous graph, produced by scientist Michael Mann and colleagues, and then reproduced in a 2001 report by the Intergovernmental Panel on Climate Change, dramatically captures temperature change over time. Climate change skeptics made it the center of an all-out attack on climate science.
The rising public awareness of climate change, and battles over what to do about it, emerged alongside awareness of other environmental issues in the 1960s and ’70s. Rachel Carson’s 1962 book Silent Spring , which condemned the pesticide DDT for its ecological impacts, catalyzed environmental activism in the United States and led to the first Earth Day in 1970.
In 1974, scientists discovered another major global environmental threat — the Antarctic ozone hole, which had some important parallels to and differences from the climate change story. Chemists Mario Molina and F. Sherwood Rowland, of the University of California, Irvine, reported that chlorofluorocarbon chemicals, used in products such as spray cans and refrigerants, caused a chain of reactions that gnawed away at the atmosphere’s protective ozone layer . The resulting ozone hole, which forms over Antarctica every spring, allows more ultraviolet radiation from the sun to make it through Earth’s atmosphere and reach the surface, where it can cause skin cancer and eye damage.
Governments worked under the auspices of the United Nations to craft the 1987 Montreal Protocol, which strictly limited the manufacture of chlorofluorocarbons . In the years following, the ozone hole began to heal. But fighting climate change is proving to be far more challenging. Transforming entire energy sectors to reduce or eliminate carbon emissions is much more difficult than replacing a set of industrial chemicals.
In 1980, though, researchers took an important step toward banding together to synthesize the scientific understanding of climate change and bring it to the attention of international policy makers. It started at a small scientific conference in Villach, Austria, on the seriousness of climate change. On the train ride home from the meeting, Swedish meteorologist Bert Bolin talked with other participants about how a broader, deeper and more international analysis was needed. In 1988, a United Nations body called the Intergovernmental Panel on Climate Change, the IPCC, was born. Bolin was its first chairperson.
The IPCC became a highly influential and unique body. It performs no original scientific research; instead, it synthesizes and summarizes the vast literature of climate science for policy makers to consider — primarily through massive reports issued every couple of years. The first IPCC report, in 1990 , predicted that the planet’s global mean temperature would rise more quickly in the following century than at any point in the last 10,000 years, due to increasing greenhouse gases in the atmosphere.
IPCC reports have played a key role in providing scientific information for nations discussing how to stabilize greenhouse gas concentrations. This process started with the Rio Earth Summit in 1992 , which resulted in the U.N. Framework Convention on Climate Change. Annual U.N. meetings to tackle climate change led to the first international commitments to reduce emissions, the Kyoto Protocol of 1997 . Under it, developed countries committed to reduce emissions of CO 2 and other greenhouse gases. By 2007, the IPCC declared the reality of climate warming is “unequivocal.” The group received the Nobel Peace Prize that year, along with Al Gore, for their work on climate change.
The IPCC process ensured that policy makers had the best science at hand when they came to the table to discuss cutting emissions. Of course, nations did not have to abide by that science — and they often didn’t. Throughout the 2000s and 2010s, international climate meetings discussed less hard-core science and more issues of equity. Countries such as China and India pointed out that they needed energy to develop their economies and that nations responsible for the bulk of emissions through history, such as the United States, needed to lead the way in cutting greenhouse gases.
Meanwhile, residents of some of the most vulnerable nations, such as low-lying islands that are threatened by sea level rise, gained visibility and clout at international negotiating forums. “The issues around equity have always been very uniquely challenging in this collective action problem,” says Rachel Cleetus, a climate policy expert with the Union of Concerned Scientists in Cambridge, Mass.
By 2015, the world’s nations had made some progress on the emissions cuts laid out in the Kyoto Protocol, but it was still not enough to achieve substantial global reductions. That year, a key U.N. climate conference in Paris produced an international agreement to try to limit global warming to 2 degrees C, and preferably 1.5 degrees C , above preindustrial levels.
Every country has its own approach to the challenge of addressing climate change. In the United States, which gets approximately 80 percent of its energy from fossil fuels, sophisticated efforts to downplay and critique the science led to major delays in climate action. For decades, U.S. fossil fuel companies such as ExxonMobil worked to influence politicians to take as little action on emissions reductions as possible.
Biggest footprint
These 20 nations have emitted the largest cumulative amounts of carbon dioxide since 1850. Emissions are shown in billions of metric tons and are broken down into subtotals from fossil fuel use and cement manufacturing (blue) and land use and forestry (green).
Total carbon dioxide emissions by country, 1850–2021
Such tactics undoubtedly succeeded in feeding politicians’ delay on climate action in the United States, most of it from Republicans. President George W. Bush withdrew the country from the Kyoto Protocol in 2001 ; Donald Trump similarly rejected the Paris accord in 2017 . As late as 2015, the chair of the Senate’s environment committee, James Inhofe of Oklahoma, brought a snowball into Congress on a cold winter’s day to argue that human-caused global warming is a “hoax.”
In Australia, a similar mix of right-wing denialism and fossil fuel interests has kept climate change commitments in flux, as prime ministers are voted in and out over fierce debates about how the nation should act on climate.
Yet other nations have moved forward. Some European countries such as Germany aggressively pursued renewable energies, including wind and solar, while activists such as Swedish teenager Greta Thunberg — the vanguard of a youth-action movement — pressured their governments for more.
In recent years, the developing economies of China and India have taken center stage in discussions about climate action. China, which is now the world’s largest carbon emitter, declared several moderate steps in 2021 to reduce emissions, including that it would stop building coal-burning power plants overseas. India announced it would aim for net-zero emissions by 2070, the first time it has set a date for this goal.
Yet such pledges continue to be criticized. At the 2021 U.N. Climate Change Conference in Glasgow, Scotland, India was globally criticized for not committing to a complete phaseout of coal — although the two top emitters, China and the United States, have not themselves committed to phasing out coal. “There is no equity in this,” says Aayushi Awasthy, an energy economist at the University of East Anglia in England.
Past and future
Various scenarios for how greenhouse gas emissions might change going forward help scientists predict future climate change. This graph shows the simulated historical temperature trend along with future projections of rising temperatures based on five scenarios from the Intergovernmental Panel on Climate Change. Temperature change is the difference from the 1850–1900 average.
Historical and projected global temperature change
Facing the future
In many cases, changes are coming faster than scientists had envisioned a few decades ago. The oceans are becoming more acidic as they absorb CO 2 , harming tiny marine organisms that build protective calcium carbonate shells and are the base of the marine food web. Warmer waters are bleaching coral reefs. Higher temperatures are driving animal and plant species into areas in which they previously did not live, increasing the risk of extinction for many.
No place on the planet is unaffected. In many areas, higher temperatures have led to major droughts, which dry out vegetation and provide additional fuel for wildfires such as those that have devastated Australia , the Mediterranean and western North America in recent years.
Then there’s the Arctic, where temperatures are rising at more than twice the global average and communities are at the forefront of change. Permafrost is thawing, destabilizing buildings, pipelines and roads. Caribou and reindeer herders worry about the increased risk of parasites for the health of their animals. With less sea ice available to buffer the coast from storm erosion, the Inupiat village of Shishmaref, Alaska, risks crumbling into the sea . It will need to move from its sand-barrier island to the mainland.
“We know these changes are happening and that the Titanic is sinking,” says Louise Farquharson, a geomorphologist at the University of Alaska Fairbanks who monitors permafrost and coastal change around Alaska. All around the planet, those who depend on intact ecosystems for their survival face the greatest threat from climate change. And those with the least resources to adapt to climate change are the ones who feel it first.
“We are going to warm,” says Claudia Tebaldi, a climate scientist at Lawrence Berkeley National Laboratory in California. “There is no question about it. The only thing that we can hope to do is to warm a little more slowly.”
That’s one reason why the IPCC report released in 2021 focuses on anticipated levels of global warming . There is a big difference between the planet warming 1.5 degrees versus 2 degrees or 2.5 degrees. Each fraction of a degree of warming increases the risk of extreme events such as heat waves and heavy rains, leading to greater global devastation.
The future rests on how much nations are willing to commit to cutting emissions and whether they will stick to those commitments. It’s a geopolitical balancing act the likes of which the world has never seen.
Science can and must play a role going forward. Improved climate models will illuminate what changes are expected at the regional scale, helping officials prepare. Governments and industry have crucial parts to play as well. They can invest in technologies, such as carbon sequestration, to help decarbonize the economy and shift society toward more renewable sources of energy.
Huge questions remain. Do voters have the will to demand significant energy transitions from their governments? How can business and military leaders play a bigger role in driving climate action? What should be the role of low-carbon energy sources that come with downsides, such as nuclear energy? How can developing nations achieve a better standard of living for their people while not becoming big greenhouse gas emitters? How can we keep the most vulnerable from being disproportionately harmed during extreme events, and incorporate environmental and social justice into our future?
These questions become more pressing each year, as carbon dioxideaccumulates in our atmosphere. The planet is now at higher levels of CO 2 than at any time in the last 3 million years.
At the U.N. climate meeting in Glasgow in 2021, diplomats from around the world agreed to work more urgently to shift away from using fossil fuels. They did not, however, adopt targets strict enough to keep the world below a warming of 1.5 degrees.
It’s been well over a century since chemist Svante Arrhenius recognized the consequences of putting extra carbon dioxide into the atmosphere. Yet the world has not pulled together to avoid the most dangerous consequences of climate change.
Time is running out.
More Stories from Science News on Climate
Dry farming could help agriculture in the western U.S. amid climate change
How wildfires deplete the Earth’s ozone layer
Wildfires in boreal forests released a record amount of CO 2 in 2021
Many Antarctic glaciers are hemorrhaging ice. This one is healing its cracks
An incendiary form of lightning may surge under climate change
Greta Thunberg’s new book urges the world to take climate action now
Rapid melting is eroding vulnerable cracks in Thwaites Glacier’s underbelly
Climate ‘teleconnections’ may link droughts and fires across continents
From the nature index.
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A brief history of climate change discoveries
Picture: Angelika Renner, British Antarctic Survey
50 years of Research and Innovation
For more than 50 years, research and innovation has helped to understand, tackle and mitigate the effects of climate change, and embed evidence in decision making and climate policy.
From early research proving global temperature rises and using ice cores that contain 800,000 years of continuous Earth climate records, to using supercomputers for climate modelling, we take a look at some of the most important discoveries in climate change research so far.
For more stories, profile pieces of key players in the climate change field and further information, please visit our 'Responding to Climate Change' pages.
1938 - Proof that global temperatures are rising
A little-known amateur scientist called Guy Callendar makes history by discovering the planet has warmed
In 1938, steam engineer Callendar decided to take a break from his day job and began painstakingly collecting records from 147 weather stations across the world. Doing all his calculations by hand, he discovered that global temperatures had risen 0.3°C over the previous 50 years.
Callendar argued that carbon dioxide (CO 2 ) emissions from industry were responsible for global warming. However, this was largely ignored by other scientists who didn’t believe that humans could impact such a large system as the climate.
Remarkably, despite his crude methods, Callendar’s estimates of global warming were extremely accurate and in line with modern assessments.
1954 - The birth of the solar cell
Three scientists invent the world’s first practical solar cell
In 1952, Bell Labs, the research branch of the Bell Telephone Company in New Jersey, asked engineer Daryl Chapin to solve a problem.
The company wanted to extend its network of telephones in remote tropical regions. However, the standard batteries used at the time were unsuitable as they degraded too quickly in the hot, humid, conditions. Chapin was asked to look into other power sources and immediately thought solar power might work.
Solar cells, which convert sunlight into electrical current, were invented more than a hundred years ago. However, the earliest were too inefficient to be of much use.
The solar cells on the market in the early 50s were made from selenium, but these produced just five watts per square metre, converting less than 0.5% of the incoming sunlight into electricity.
Calvin Fuller and Gerald Pearson , at the time, were developing transistors made from silicon and Chapin asked them for their help. Pearson and Fuller were experimenting with introducing different impurities into the silicon to boost its conductivity. As an experiment, the pair used gallium to give the silicon a positive charge and then dipped it into hot lithium to create a negative charge. They attached an ammeter — a device for measuring current — and switched on a desk light. The ammeter recorded the highest current flow yet seen in a solar cell, and Pearson immediately told Chapin to focus on silicon for his solar cells. The trio worked on their technology until they had a reliable cell that could convert 6% of solar energy into electricity.
ABOVE: Amateur scientist Guy Callendar’s crude estimates of global warming were extremely accurate – and in line with modern assessments. Picture: G.S. Callendar Archive, University of East Anglia
ABOVE: Solar panel from SPECIFIC Innovation and Knowledge Centre at Swansea University, co-funded by the Engineering and Physical Sciences Research Council (EPSRC), Innovate UK and the Welsh Government. SPECIFIC’s mission is to create ‘Active Buildings’ that harness all the energy a building needs from sunlight, as well as provide occupants with low-carbon energy for transport and to supply the National Grid. Picture: SPECIFIC
ABOVE: Measurements of the amount of CO 2 in water and in the air, made over five years in the 1950s and 60s by Charles David Keeling, provided unequivocal proof that CO 2 concentrations were rising. It led to the Keeling Curve, which has documented daily changes in CO 2 levels for over six decades. Keeling’s discovery is acknowledged as one of the most important scientific works of the 20 th century.
ABOVE: In 1967, researchers Syukuro Manabe and Richard Wetherald produced the world’s first accurate computer model of planet Earth’s climate – it predicted that doubling concentrations of CO 2 in the atmosphere could raise global temperatures by 2 degrees. Picture: Getty Images
ABOVE: The JASMIN supercomputer provides environmental scientists with access to very large sets of environmental data, which are typically too big for them to download to their own computers. It can reduce the time it takes to test new ideas and get results from months to hours. Picture: JASMIN
1958 - CO 2 levels are rising, and fossil fuels are to blame
Dr Charles David Keeling provides the first evidence that CO 2 levels are rising
In 1958, a young postgraduate geochemist called Charles David Keeling decided to compare the amounts of CO 2 in water and air.
Nobody had ever really tried to measure the level of CO 2 in the atmosphere before, so there was no off-the-shelf equipment he could use.
He designed his own apparatus and set off to a weather observation station on the top of the Mauna Loa volcano in Hawaii. Once there, he took meticulous measurements every day and within five years he had provided the first unequivocal proof that CO 2 concentrations were rising.
What’s more, by analysing the CO 2 in his samples, Dr Keeling was able to attribute this rise to the use of fossil fuels.
Although some scientists in the 19 th century had argued that burning fossil fuels could increase CO 2 levels in the atmosphere, these concerns had remained largely hypothetical.
Dr Keeling’s discovery was one of the most important scientific works of the 20 th century. Since then, daily readings at Mauna Loa have continued almost uninterrupted for more than 60 years. The 'Keeling Curve', which documents changes in CO 2 levels over time, is the longest continuous record of CO 2 concentrations in the world.
1967 - Earth’s changing climate modelled for first time
Scientists create the first computer model of planet Earth’s climate. The model predicts that doubling concentrations of CO 2 could raise global temperatures by 2°C
In 1967, researchers Syukuro Manabe and Richard Wetherald produced the world’s first accurate computer model of planet Earth’s climate.
The model looked at all the different components that contribute to climate, including the atmosphere, oceans and clouds, and the relationships between them.
It even allowed researchers to adjust levels of CO 2 to see what impact this would have on global temperatures.
Manabe and Wetherald wrote that:
‘According to our estimate, a doubling of the CO 2 content in the atmosphere has the effect of raising the temperature of the atmosphere (whose relative humidity is fixed) by about 2°C.’
Measurements from the pre-industrial revolution through to today match that prediction extremely well. Since the 1880s we have increased CO 2 by about 50%, and temperatures have increased by 1.1°C.
Syukuro Manabe is one of three scientists to have been awarded the 2021 Nobel Prize in Physics for his work on understanding complex systems, such as the Earth's climate.
Supercomputer empowers next generation of climate models Unlike Manabe and Wetherald, today's scientists have access to a huge amount of climate data from satellites. However, the computing power needed to process that data is astronomical. For example, the current Sentinel Earth observation satellites produce 10 terabytes of data every day which is the equivalent to data from 8.7 million WhatsApp messages going through the network every minute!
This is where the JASMIN supercomputer comes in. JASMIN provides environmental scientists with access to very large sets of environmental data, which are typically too big for them to download to their own computers. It can also reduce the time it takes to test new ideas, as well as give results in hours rather than months. JASMIN is operated by the Science & Technology Facilities Council ’s (STFC) RAL Space Centre for Environmental Data Analysis (CEDA) on behalf of the Natural Environment Research Council (NERC).
1968 - Scientist predicts melting ice caps
Dr John Mercer, a glaciologist at Ohio State University in Columbus, warns that global warming could cause Antarctic ice sheets to collapse, leading to a disastrous rise in sea levels
In 1968, Dr Mercer was conducting fieldwork at the Reedy Glacier in West Antarctica when he discovered evidence of a former freshwater lake, 1,400 metres high up in the Transantarctic Mountains.
Dr Mercer took that as evidence that the entire West Antarctic Ice Sheet had once melted away, something that previously had been thought to be impossible.
His landmark paper found evidence that sea levels rose six metres in the previous interglacial period, around 120,000 years ago. Temperatures at that time were 6-7°C higher than they are today.
In his study, Dr Mercer called the West Antarctic Ice Sheet a 'uniquely vulnerable and unstable body of ice'.
He warned that current atmospheric warming could once more cause the ice shelves to disintegrate, causing a sea level rise of about five metres.
It took a while for his warning to take hold. However, this changed when, in 1995 the massive Larsen A ice shelf collapsed. The B ice shelf followed in 2002, and then in 2017 there was a major rift in Larsen C. In 2014, a team of scientists reported that the loss of ice in the Amundsen Sea Embayment had accelerated and appeared 'unstoppable'.
1969 - Earth’s temperature measured with satellites for first time
NASA’s Nimbus III satellite is launched into orbit – it provides the world’s first accurate measurement of global atmospheric temperatures
The Nimbus satellites revolutionised how scientists study the Earth’s climate, weather systems and atmosphere.
First launched in 1964, over the course of 30 years the series of satellites provided us with never-before-seen data on global temperatures, the concentration of greenhouse gases in the atmosphere, the ozone layer, as well as sea ice thickness. It also allowed scientists to develop computer models that could forecast weather a week, or even two weeks, in advance, virtually impossible beforehand.
The Nimbus III satellite was the first to include instruments that could measure atmospheric temperature. This provided an independent satellite record confirming that the Earth’s lower atmosphere was warming.
New generation of climate satellites Today’s satellites are of course capable of more sophisticated measurements. For instance, huge advances in measuring global surface temperatures have been made by British scientists at RAL Space. RAL Space carry out world-class science research and technology development, with significant involvement in more than 210 instruments on missions to date.
Since the 1980s, RAL Space scientists and engineers have helped develop and calibrate the Along-Track Scanning Radiometer (ATSR) series, considered to be one of the most accurate remote sensing instruments in the world. The ATSR can measure sea and land surface temperatures to unprecedented accuracy.
RAL Space also helped develop the Sea and Land Surface Temperature Radiometer (SLSTR) for the Sentinel satellites, which form part of the European Union's Copernicus Earth observation programme. The satellites are providing us with an extraordinary picture of how Earth’s climate is changing.
ABOVE: Glaciologist Dr John Mercer’s work in Antarctica in the 1960s led him to conclude that current atmospheric warming could cause ice shelves to disintegrate, causing a sea level rise of about five metres – a warning borne out by the collapse of the Larsen A ice shelf in 1995. Picture: Getty Images
ABOVE: Sentinel 3. Technology deployed on the Sentinel series of satellites can measure sea and land temperatures with unprecedented accuracy. STFC engineers at RAL Space played a key role in developing the technology. Picture: STFC
ABOVE: Ice cores provide key information about what the Earth’s climate was like in the past. The deeper you dig the further back in time you go. This slice shows the bubbles of trapped air thousands of years ago. This provides key information about what the Earth's climate was like in the past. Picture: Pete Bucktrout, British Antarctic Survey
ABOVE: The ozone hole above the Antarctic was discovered in 1985 by British Antarctic Survey Scientists. Here, from left, Dr Joe Farman, Brian Gardiner and Jon Shanklin are photographed with a Dobson ozone spectrophotometer, used to determine stratospheric ozone concentrations. Picture: Chris Gilbert, British Antarctic Survey
1985 - Drilling 150,000 years deeper into the ice
Ice cores extracted from Antarctica confirm that CO 2 and temperature have gone up and down together over the past 150,000 years
Ice cores provide key information about what the Earth’s climate was like in the past.
Bubbles sealed in the ice provide a unique snapshot of the atmosphere at the time. Scientists can also work out what surface temperatures were like in the past by analysing the ratio of ‘heavy’ atoms of oxygen and hydrogen.
The deeper you dig, the further back in time you go. So, when a team of French and former Soviet scientists extracted an Antarctic ice core over 2,000 metres long in 1985, they were able to tell what atmospheric conditions were like 150,000 years ago.
In 1998 the team extracted an even longer ice core, extending the climate record back to 420,000 years ago.
Both cores showed a clear relationship between levels of atmospheric greenhouse gases and Antarctic temperature over time. As greenhouse gases had gone up, so had temperatures.
What’s more, they showed that present levels of CO 2 and methane in the atmosphere are above anything seen in the past 420,000 years.
In 2004, ice core scientists at British Antarctic Survey (BAS) were part of a team that extracted a three-kilometre ice core from the Antarctic. This core contains a record of the Earth’s climate stretching back 800,000 years, giving us by far the oldest continuous climate record yet obtained from ice cores.
Together Antarctic ice cores show us that the concentration of CO 2 was stable over the last millennium until the early 19th century. It then started to rise, and its concentration is now nearly 50% higher than it was before the industrial revolution.
1985 - Ozone hole discovery
Scientists discover a hole in the ozone layer above Antarctica
The ozone layer in the Earth’s atmosphere naturally protects us from harmful ultraviolet (UV) light. So, when in 1985, three scientists from BAS reported that they had detected abnormally low levels of ozone over the South Pole, the world was shocked.
They suggested that compounds called chlorofluorocarbons (CFCs), often used in aerosol cans and fridges, could be responsible. Their findings led to the Montreal Protocol in 1987, which called for the reduction, and then total ban of CFCs. The protocol is one of the most successful global environmental policies of the twentieth century, and helped raise public awareness of climate change.
A NERC commissioned analysis estimated that, had the discovery of the ozone hole been delayed by five to 10 years, the cost of this delay would have resulted in 300 more skin cancer cases every year in the UK by 2030, costing the country around £550 million a year in today's money. The Antarctic ozone hole is now slowly healing.
Interviews: Dr Anna Jones , Interim Director of Science at British Antarctic Survey (BAS) and Jonathan Shanklin , one of the scientists behind the discovery of the hole, whose work has been instrumental in preserving this vital shield for four decades.
ABOVE: Sunderland-based Hyperdrive Innovation develops and manufactures market-leading lithium-ion battery technology to power green transport and provide innovative energy storage. Innovate UK has been part of Hyperdrive’s journey from the start. Picture: Hyperdrive
ABOVE: The next generation of battery technologies is not limited to automobiles. In September 2021, Rolls-Royce’s fully electric aircraft, Spirit of Innovation , completed its maiden flight over Boscombe Down in Wiltshire. Half of the project’s funding is provided by the UK’s Aerospace Technology Institute , in partnership with the Department for Business, Energy & Industrial Strategy , and Innovate UK . Picture: Rolls-Royce
ABOVE: Formed in 1988, the Intergovernmental Panel on Climate Change heralded a new era of climate research. Its reports provide policymakers with regular scientific assessments on the current state of knowledge about climate change. NERC scientists have authored and reviewed key chapters in every report to date. Picture: Getty Images
1985 - The lithium-ion battery is invented
Japanese scientist Professor Akira Yoshino develops the world’s first rechargeable lithium battery. The lightweight battery ushers in a revolution in energy storage, eventually powering portable devices from mobile phones to laptop computers
In a lithium-ion battery, lithium ions move from the negative electrode (anode) to the positive electrode (cathode), through an electrolyte. When you plug the battery in to recharge, the ions move back in the opposite direction.
The idea to build a rechargeable lithium battery was first proposed by British scientist Professor Stanley Whittingham, who started developing one while working for the oil company Exxon in the 1970s. His prototype used a lithium-metal anode and a titanium disulfide cathode. The battery was rechargeable, but high manufacturing costs and safety concerns meant the technology could not be commercialised.
In the early 1980s, American Professor John Goodenough improved on the design by incorporating cathodes made from cobalt oxide. This greatly improved the storage capacity of the battery.
However, it wasn’t until Professor Yoshino made changes that dramatically improved the safety of the batteries that commercial production could begin. His design pioneered the use of carbon-rich anode materials into which lithium-ions could be inserted.
Next generation batteries Since their invention in 1985, advances in the technology of rechargeable batteries have brought us closer to a dream of a completely fossil-fuel free society.
In 1995, while at the University of St Andrews, Professor Peter Bruce, a materials scientist funded by the Engineering and Physical Sciences Research Council (EPSRC), led the development of a rechargeable lithium-ion battery that revolutionised the electronics industry.
The battery was lighter, more reliable, more efficient and greener than the Nickel Cadmium (NiCad) battery used extensively at the time.
Over the years he has continued to make important advances in the science underpinning rechargeable lithium batteries, enhancing their ability to store and retain charge.
An electrode material developed by Professor Bruce was used in the first generation of modern electric vehicle batteries, as seen in cars such as the Nissan Leaf and Vauxhall Ampera.
He is also one of the pioneers of the lithium-air battery, which has the highest theoretical energy density of any battery and could transform energy storage. It has significant potential for use in electric vehicles.
The next generation of rechargeable batteries being developed by Professor Bruce, now at the University of Oxford, and others, will have a crucial role in improving air quality, lowering greenhouse gas emissions and helping us move to a fossil-fuel free world.
1988 - The Intergovernmental Panel on Climate Change (IPCC) heralds a new era of climate research
The IPCC provides policymakers with regular scientific assessments on the current state of knowledge about climate change
Established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO), the Intergovernmental Panel on Climate Change (IPCC) is the United Nations body responsible for assessing the science related to climate change.
So far, the IPCC has published five Assessment Reports written by the world’s most renowned experts on climate change. These are the most comprehensive scientific reports produced about climate change worldwide.
Since 1990 these reports have consistently found that the Earth is warming, and that the release of greenhouse gases by humans is responsible.
Driving policy action The five reports have been the cornerstone upon which international climate change negotiations have relied.
In 1990, the First IPCC Assessment Report played a decisive role in the creation of the United Nations Framework Convention on Climate Change, a key international treaty to reduce global warming and cope with the consequences of climate change.
The Second Assessment Report in 1995 led to the 1997 Kyoto Protocol, which further committed industrialised countries to limit and reduce their greenhouse gas emissions to individually agreed targets.
Finally, the Fifth Assessment Report provided the foundation for the 2015 Paris agreement where 195 countries agreed to limit global warming to less than 2°C above preindustrial levels.
Bringing together the world’s best experts Each Assessment Report includes analysis of several thousand published scientific papers, written and edited by the very best experts in their field.
For the latest three IPCC Special Reports , IPCC authors assessed around 20,000 publications and considered around 100,000 comments from more than 2,500 experts.
Many of these authors are funded by NERC, the driving force of investment in environmental science in the UK.
NERC scientists have authored and reviewed chapters in every single IPCC report to date, offering expertise in:
· Climate history · Loss of ice from ice sheets and glaciers · Ocean circulation and ocean warming · Climate modelling · Sea level rise
Data from key figures of the Summary for Policymakers section of the latest IPCC report are now available for anyone to access from the CEDA Archive . This is the first time SPM figure data has been available on the same day as report publication.
The next Assessment Report is due in 2022.
1991 - Wind power takes off in the UK
The UK’s first wind farm is constructed in Cornwall and it includes 10 turbines that together produce enough electricity for approximately 2,700 homes
Delabole Wind Farm in North Cornwall was the first commercial wind farm in the UK, completed and commissioned in 1991 by the Edwards family.
Since then, the UK has continued to embrace wind energy.
The UK's first demonstration offshore wind farm was installed in December 2000 off the Northumberland coast. It consisted of two 2 megawatt (MW) wind turbines with a rotor diameter of 66 metres. At the time, these were the largest turbines installed offshore in the world.
North Hoyle, the UK’s first commercial wind farm, followed shortly afterwards in 2003. It was situated off the North Wales coast, and consisted of 30 turbines with a rotor diameter of 80 metres, each producing 2MW.
Fast forward to today, and Britain is the global leader in offshore wind energy, with offshore turbines contributing around 10% of the UK's power in the third quarter of 2019.
That year, the world’s largest, and the very first, one gigawatt offshore wind farm began operation off the Yorkshire coast. Hornsea One has a whopping 174 turbines, each producing 7MW, and is almost double the capacity of the previous largest offshore wind farm.
The UK’s offshore wind capacity is set to double over the next decade.
Success story Perhaps the main reason that the UK has been so successful at harnessing wind is down to its investment in state-of-the-art testing facilities.
Since 2003, world-class testing facilities have allowed companies to trial and test offshore wind rotor blades at Blythe in Northumberland. This site, now run by the Offshore Renewable Energy ( ORE ) Catapult, allows companies to see how turbine blades work in real-world conditions. This allows engineers to make improvements and identify problems early on, helping to reduce risk and drive down the cost of offshore renewable energy.
The ORE Catapult also hosts the Levenmouth Demonstration Turbine , the world’s most advanced, open-access offshore wind turbine dedicated to R&D.
The towering 7MW turbine has been used as a test facility by:
. Companies supplying sub-sea electrical cables to wind farms . Innovative start-ups developing novel turbine blades or making robots to inspect foundations . Universities developing new software to control the turbines themselves
1992 - Coral reefs at threat
Scientists realise that higher levels of CO 2 in the ocean will make it harder for corals and other animals to build reefs
When CO 2 dissolves in the ocean, it raises the water's acidity level.
This stops corals from sucking in a vital mineral called calcium carbonate, which they use to build their skeletons.
US scientists Professor Stephen Smith and Professor Robert Buddemeier were the first to warn of this consequence of ocean acidification. Since then, evidence that there's a problem has continued to mount.
It’s not just corals that are at risk; all creatures that form shells are in danger, including oysters, mussels, clams and some planktonic species.
For instance, research by Dr Steve Widdicombe from Plymouth Marine Laboratory has shown that burrowing heart sea urchins are extremely vulnerable to ocean acidification.
If sea urchins were to die out, this would have far-reaching implications. That’s because these digging creatures act like earthworms, stirring up the seabed and releasing nutrients for other organisms to use.
ABOVE: From its first wind farm in 1991, the UK has embraced wind energy and is now a driving force in research and development. The Levenmouth Demonstration Turbine (pictured) is the world’s most advanced, open-access offshore wind turbine dedicated to R&D. It is operated by the Offshore Renewable Energy Catapult, one of a network of Catapults set up by Innovate UK in high growth industries. Picture: ORE Catapult
ABOVE: Working with the Offshore Renewable Energy Catapult, BladeBUG is developing advanced robots to autonomously assist technicians in the inspection and repair of wind turbine blades. Picture: Blade Bug
ABOVE: When CO 2 dissolves in the ocean, it raises the water's acidity level. High acidity can kill any creature that forms a shell, including coral. Coral provide a vital ecosystem for life underwater as well as a crucial source of income for millions of people. Picture: NERC
ABOVE: The United Nations Framework Convention on Climate Change was the first international treaty designed to limit greenhouse gas emissions. It led directly to the 1995 Kyoto Protocol, which committed industrialised countries and economies to limit and reduce greenhouse gases emissions. Picture: Getty Images
ABOVE: Since 1996 the Sleipner field in the Norwegian sector of the North Sea has been capturing about one million tonnes of CO 2 each year and storing it in a saline formation 1 km below the seabed. Picture: Øyvind Hagen/©Equinor
1994 - First climate change legislation comes into force
197 countries sign up to the first global treaty to combat climate change
The United Nations Framework Convention on Climate Change (UNFCCC) was the first international treaty designed to limit greenhouse gas emissions and prevent climate change.
It entered into force on 21 March 1994, and has been ratified by 197 countries.
This also led directly to the 1995 Kyoto Protocol, which committed industrialised countries and economies to limit and reduce greenhouse gases emissions in accordance with agreed individual targets.
This was then superseded by the Paris Agreement in 2015, which legally requires countries to reduce their carbon emissions in order to limit global warming to 1.5°C compared to pre-industrial levels.
1996 - Capturing carbon underground
The world’s first carbon storage project gets underway
Carbon capture (CC) is when you take greenhouse gases produced by industrial plants, power stations and other sources, and store it underground. This stops CO 2 from being released into the atmosphere, preventing further global warming.
The world’s first commercial CO 2 storage project began operation in 1996 at the Sleipner gas field in the North Sea.
Since then, about 1 million tonnes of CO 2 from natural gas have been captured and stored every year. This equates to more than 20 million tonnes of CO 2 , equivalent to the annual emissions from 10 million cars.
Proving carbon storage is safe and feasible It’s now accepted that carbon capture is essential if we are to get to zero emissions by 2050, however at one time the technology was seen as potentially risky. Governments and the public needed convincing that the technology was safe and feasible.
Since its inception, scientists from the British Geological Survey (BGS) have monitored the Sleipner carbon storage site. Using advanced 3D imaging studies, BGS were able to track the precise location of CO 2 before and after injection. Their work showed that all of the captured CO 2 is securely confined within the storage reservoir.
This demonstrated the safety and feasibility of CO 2 storage, changing the way it was seen by scientists, policymakers and the public. Find out more about the latest on carbon capture in our podcast on the topic.
1997 - Hybrid cars invented
The first mass-market electric hybrid car is produced by Toyota
Although the electric car was developed by the Scottish inventor Robert Anderson in the 1830s, it wasn't until Toyota released the Prius in Japan in 1997 that the first step had been taken towards a viable alternative to fossil-fuel powered mass-produced cars.
Fast forward to today, and the electric vehicle (EV) revolution is in full swing.
Jaguar plans to sell only electric cars from 2025, Volvo from 2030 and Lotus from 2028.
It’s not just luxury car manufacturers, General Motors says it will only make EVs by 2035, Ford plan to only sell electric cars in Europe by 2030, and VW says 70% of its sales will be electric by 2030.
Industry insiders believe we will soon pass the tipping point where sales of EVs will very rapidly outpace petrol and diesel cars.
This success is all down to rapid advances in technology. Improvements have been made in the motors that drive EVs, the computers that control them, and most importantly, the batteries that power them.
Thanks to those advances modern batteries last much longer, and can store much more energy than batteries produced just five years ago.
The work doesn’t stop there though as researchers and innovators are continuing to work on making EV batteries safer, more powerful, cheaper, faster-charging and easier to recycle.
2003 - Scientists link extreme weather to climate change
A heatwave in Europe kills tens of thousands of people – scientists say that climate change is to blame
Flash floods and heatwaves seem to be happening almost every year in Britain, but is this just a coincidence?
Up until a few years ago, it wasn’t possible to draw a link between extreme weather and climate change with any degree of accuracy.
However, that changed in 2004 when Professor Pete Stott, a scientist at the UK Met Office, published a paper in the scientific journal Nature showing that climate change had doubled the risk of the 2003 European heatwave that killed tens of thousands of people.
His finding led to a growing scientific movement called extreme event attribution. This is where researchers point to an extreme weather event and use climate modelling to say whether the likelihood of the event happening would be the same in a world without climate change.
Today’s scientists are able to calculate the impact of global warming on droughts, heatwaves and floods with remarkable accuracy.
One of the leading experts in the field of extreme event attribution is Dr Friederike Otto, Deputy Director of the UKRI-funded Environmental Change Institute (ECI) at the University of Oxford.
Dr Otto showed that the 2018 heatwave that engulfed northern Europe was made twice as likely due to climate change. She also found that the risk of extreme rainfall in any given winter has risen by 25%.
ABOVE: The Toyota Prius was launched in October 1997 as the world's first mass-produced hybrid passenger vehicle. It came with the tagline: ‘Just in time for the 21st century.’ The first step had been taken towards a viable alternative to entirely fossil-fuel powered cars. Picture: Toyota
ABOVE: Lithium-ion batteries are used to power most electric vehicles, and it’s essential that they can be safely and economically managed at the end of their useful life. The UKRI-funded Faraday Institution’s ReLib project is developing robotic technologies to disassemble spent battery packs for potential reconditioning and reuse as part of a circular economy. Picture: Faraday Institution
ABOVE: Research by Dr Friederike Otto at the UKRI-funded Environmental Change Institute showed that the 2018 heatwave that engulfed northern Europe was made twice as likely due to climate change. She also found that the risk of extreme rainfall in any given winter has risen by 25%. Picture: Brad Wakefield
ABOVE: If seawater temperatures increase in the polar regions, bubbles of methane could rise to the surface, causing even more warming in the atmosphere. Methane has a warming effect approximately 20 times stronger than CO 2 . Picture: Getty Images
2007 - The Arctic is warming twice as fast as the rest of the planet
Polar regions are warming twice as fast as the rest of the Earth, putting polar bears and other wildlife at risk
The International Polar Year 2007-2008 was the largest campaign ever mounted to explore Earth’s polar regions.
Around 50,000 scientists, students and support staff from over 60 nations convened to unlock the secrets of the Arctic and Antarctic.
What they found was alarming. The Greenland ice sheet, parts of the Antarctic ice sheet, and Arctic sea ice are melting at rates that are unprecedented in the last 10,000 years.
Climate change is already having a measurable effect on lifeforms throughout the food chain, from microbes to polar bears.
The poles are also warming faster than the rest of the planet, one of the key predictions of climate models.
One of the reasons for this increased warming is due to something called Ice-albedo feedback. Ice is highly reflective, so a lot of solar radiation that hits the polar regions bounces back into space.
However, as the planet warms and ice caps melt, less light is reflected, leading to even more warming.
This is an example of 'positive feedback' in climate change, where warming accelerates further change.
Methane plumes Another example of positive feedback that climate scientists are worried about is methane.
Methane is a powerful greenhouse gas, with a warming effect approximately 20 times stronger than CO 2 . In cold waters it is commonly found in the seabed as methane hydrate. However, if seawater temperatures rise, bubbles of methane could rise to the surface causing even more warming in the atmosphere.
During the International Polar Year, scientists at NERC witnessed this very process occurring.
The scientists were surveying the Arctic seabed when they spotted plumes of the powerful greenhouse gas methane rising from the seafloor off Spitsbergen , an island in the Svalbard archipelago in northern Norway.
A rise of just 1 degree Celsius over recent decades meant that methane hydrate, which was once stable, was breaking down, releasing methane.
This was the first time scientists had found evidence suggesting such seeps are due to ocean warming.
2008 - The UK Climate Change Act is enshrined in law
The Act becomes the world’s first long-term legally binding framework for tackling climate change
The Act requires the government to set binding five-year carbon budgets based on the latest science.
In 2008 the Act committed the UK to reduce its greenhouse gas emissions by 80% by 2050, compared to 1990 levels. However, this target was made more ambitious in 2019 when the UK became the first major economy to commit to a ‘net zero’ target .
A review of the Act by the Grantham Research Institute on Climate Change in 2018 found that its carbon budgets have helped reduce emissions in the UK, particularly in the power sector.
2015 - Landmark international Paris agreement reached to cut carbon
196 countries sign up to the Paris Agreement, and agree to limit global warming to less than 2°C above pre-industrial levels
The Paris Agreement is a legally binding international treaty on climate change. It was adopted by 196 countries on 12 December 2015, and entered into force on 4 November 2016.
Its goal is to limit global warming to 1.5°C, compared to pre-industrial levels.
As part of the agreement, nations set their own legally binding targets for greenhouse gas cuts and report their progress every five years.
2019 - Ice collapse ‘irreversible’
Ice sheets in Antarctica and Greenland may have already passed the point of no return; their collapse could raise sea levels by 10 metres
A special report by the Intergovernmental Panel on Climate Change (IPCC) warns that part of an ice sheet known as the Amundsen Sea embayment of West Antarctica might have already passed a tipping point, with collapse now unavoidable.
Climate models suggest that when this sector collapses, it could destabilise the rest of the West Antarctic ice sheet like falling dominoes. This would cause sea levels to rise by three metres over a timescale of centuries to millennia.
The report says that part of a separate East Antarctic ice sheet known as the Wilkes Basin might also be unstable.
The Greenland ice sheet is also melting at an accelerating rate, and could add a further seven metres to sea levels. Models show that the Greenland ice sheet will collapse when the Earth warms to 1.5°C above pre-industrial levels, which could happen as soon as 2030.
The collapse of these three ice sheets will raise sea levels by around 10 metres over the period of thousands of years. However, how quickly they rise depends on the magnitude of global warming.
If we limit warming to 1.5°C, it could take 10,000 years to unfold. Above 2°C it could take less than 1,000 years.
Monitoring glaciers in Antarctica The predictions of irreversible ice collapse are all based on computer models, but computer simulations need to be confirmed with real-world observations.
Since 2018, researchers from NERC have been conducting a whole suite of measurements on two Antarctic glaciers; the Thwaites Glacier and Pine Island Glaciers .
These glaciers form part of the Amundsen Sea embayment, which the IPCC predicts could have already passed the point of no return.
NERC’s research is looking at what’s causing ice loss at these glaciers, and how it will impact global sea levels.
For example, scientists are using aircraft to take radar measurements to look deep below the surface of the ice and build a clear picture of how different layers of ice and the bedrock interact. This is crucial in understanding how climate change will affect large ice sheets.
ABOVE: A British Antarctic Survey Twin Otter aircraft coming in to land at its Rothera base. Twin Otters, often termed a ‘bush’ aircraft as they are designed for remote environments, are extremely versatile and can be modified to allow airborne surveying and other scientific equipment to be fitted. Picture: Dave Wattam, British Antarctic Survey
ABOVE: The Greenland and Antarctic ice sheets are melting at an accelerating rate. Their collapse could raise sea levels by 10 metres. Picture: Picture: Danielle Barnes, Unsplash
ABOVE: Sumatran tigers are a critically endangered carnivore restricted to the island of Sumatra. Like many other large mammals on the Indonesian archipelago, they are threatened by high levels of poaching and widespread habitat degradation. Picture: Mark Mallett, UKRI
ABOVE: Critically endangered Hawksbill turtles help maintain the health of coral reefs. As they remove prey such as sponges from the reef's surface, they provide better access for reef fish to feed. They also have cultural significance and tourism value. Picture: Getty Images
ABOVE: Green shoots: One of the reasons that the UK was able to commit to reaching net zero in 2019 was because research showed that, not only was it possible, it would actually bring economic benefits. Picture: Getty Images
2019 - Variety of life on Earth being lost at “unprecedented” pace
Up to one million animal and plant species are now threatened with extinction, and many could die out within decades
A 2019 report by the UN found that the number of native species on the planet has plummeted since 1900.
The report , written by 145 experts from 50 countries, is the most comprehensive assessment of global biodiversity ever to take place.
It found that at least 680 vertebrate species have been driven to extinction since the 16th century.
The rate of species extinctions is also accelerating, with grave impacts on people around the world.
More than 40% of amphibian species are now at risk of extinction. Over a third of all marine mammals and 33% of reef-forming corals are also threatened.
The main factors driving this mass extinction are changes in land and sea use, direct exploitation of organisms, climate change, pollution and the introduction of invasive alien species.
The assessment was compiled by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), often described as the “IPCC for biodiversity”. IPBES is an independent intergovernmental body which is made up of more than 130 governments.
The report was compiled by 145 expert authors from 50 countries over the past three years. Many of these experts were NERC-funded scientists, who have acted as editors and expert consultants for this report, and previous IPBES reports.
2019 - UK first country to pass net zero emissions law
The UK is the first major economy in the world to pass laws to end its contribution to global warming by 2050
In 2019, the UK committed to reducing greenhouse gas emissions to net zero by 2050.
Net zero is when the amount of greenhouse gas emissions produced is the same as the amount removed from the atmosphere.
This means any emissions are balanced by schemes to offset an equivalent amount of greenhouse gases from the atmosphere, such as planting trees or using technology like carbon capture and storage.
The target will require the UK to bring all greenhouse gas emissions to net zero by 2050, compared with the previous target of at least 80% reduction from 1990 levels.
Science behind the policy One of the reasons that the UK was able to commit to reaching net zero was because research showed that, not only was it possible, it would actually bring economic benefits.
This was the advice that researchers at the UK Energy Research Centre (UKERC) gave the Climate Change Committee, an independent, statutory body which provides independent advice on setting and meeting carbon budgets and preparing for climate change.
2020 - World record set for solar power
Oxford PV , a spin out company from the University of Oxford, sets a world record with a cell that can convert 29.52% of solar energy into electricity
The solar cells made by Oxford PV are coated with a thin film of the material perovskite to boost conductivity.
With support from EPSRC, the company has teamed up with scientists at the University of Oxford to produce a solar cell with 37% efficiency within five years. These initial products, designed for residential roofs, will generate 20% more power from the same number of cells than current solar cells on the market.
2021 - Many aspects of climate change are now inevitable and irreversible
Scientists predict the world will reach 1.5C of warming by 2040, earlier than initial warnings. That level of warming will lead to more heatwaves, intense storms, droughts and floods
The findings are reported in the latest Assessment Report by the IPCC, the world’s leading authority on climate science.
The report delivers scientists’ starkest warning yet about the deepening climate emergency. It warns that we are already observing changes in the Earth’s climate that are unprecedented in thousands, if not hundreds of thousands of years.
They include more intense rainfall and associated flooding, more intense drought in many regions, sea level rises in coastal areas, permafrost thawing, ocean acidification and others.
The report says that these changes are 'unequivocally' caused by humans burning fossil fuels.
The assessment predicts that temperatures are likely to rise to more than 1.5°C above pre-industrial levels within just two decades.
This means that many changes such as sea level rises, the melting of Arctic ice and the warming and acidification of the oceans, are now irreversible and set in stone.
It’s not too late to prevent further warming of 2°C; through drastically reducing carbon emissions in the next decade.
The 1.5C target is crucial, because beyond this point climate tipping points become more likely.
Tipping points are when rising temperatures trigger a series of cascading events with dire consequences. For example melting Arctic permafrost releases methane into the atmosphere, which causes even more warming.
ABOVE: Oxford PV is pioneering a new generation of solar cells that could transform the economics of silicon solar technology. Picture: Oxford PV
ABOVE: A NERC-supported researcher from the University of Bristol sampling water from the Greenland Ice Sheet for later methane analysis. The team have found that the Ice Sheet emits tons of methane, showing that subglacial biological activity impacts the atmosphere far more than previously thought. Picture: Marie Bulinova
Climate change is a global issue and concern around the world. Its impact is being felt now with more to come in the near future if we cannot limit greenhouse gases. All eyes will be on the COP26 global summit which will focus on slowing the rate at which the planet is warming.
Today, the UK is at the forefront of a new, green industrial revolution. Research and innovation continue to underpin the UK’s commitment to:
· Achieving a net zero economy by 2050 · Respond to the challenges of climate change · Live more sustainably
Across UKRI, we invest in the cutting-edge research and innovation essential to understanding and tackling the environmental sustainability challenges that we face. With projects ranging from green transportation and agricultural transformation, to investigating our changing planet and future energy systems, researchers and innovators are working hard to support the government’s ambitious target of reaching net zero.
To find out more about these projects, and the people behind them, visit our 'Responding to Climate Change' pages.
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Scientific Consensus: Humans Are Causing Climate Change
When former Vice President Al Gore launched the movie An Inconvenient Truth in 2006 to explain the science behind climate change to the American public, surveys showed that many Americans didn’t believe in climate change, even though scientific data was building that humans actions were causing global warming.
Since then, both scientific data and public consensus have been building. A research paper published in 2013 found that 97 percent of studies on climate change published between 1991 and 2012 supported the idea that human activities are altering the Earth’s climate.
And last month, a new scientific review concluded that more than 99% of peer-reviewed scientific papers published between 2012 and 2020 find that climate change is mainly caused by humans.
For the latest study, researchers began by selecting a random set of 3,000 scientific studies related to climate change published since 2012. They combed through those studies and found four that were skeptical of climate change.
Analyzing the skeptical papers, the authors identified keywords related to skepticism. Then they created an algorithm that looked for those skeptical keywords in all of the scientific studies published about climate change since 2012—a total of 88,125 papers. The algorithm ranked the studies from most to least skeptical.
In the 88,125 papers, the researchers found a total of 28 that were implicitly or explicitly skeptical of the idea that humans are causing climate change. The skeptical studies were all published in what the authors call “minor” journals.
“Our results confirm, as has been found in numerous other previous studies of this question, that there is no significant scientific debate among experts about whether or not climate change is human-caused,” the authors wrote. “This issue has been comprehensively settled, and the reality of anthropogenic climate change (ACC) is no more in contention among scientists than is plate tectonics or evolution.”
According to a nationally-representative Gallup poll , public opinion on climate change in the U.S. has remained fairly steady over the past 20 years, with about 60 percent of adults believing that humans are the leading cause of global warming.
In addition, the poll has identified a political divergence. Over the past two decades, Democrats have become more likely to believe that climate change is a serious issue that will affect their lives, while Republicans have become less likely to believe climate change is a serious problem.
The take-home message: Over the past decade, scientific consensus has built around the notion that humans are causing climate change. At the same time, public opinion about climate change is dividing along political lines, with more Democrats and fewer Republicans believing climate change is a serious problem.
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The tables below contain all of the items that are in the timeline above, organized by category (greenhouse gases, modeling, past climate, impacts of climate change, and climate reports). If you have suggestions for additions to this timeline of the History of Climate Science Research, please contact us. Greenhouse Gases and the Greenhouse Effect
The same decade had seen a revolution in scientists' understanding of Earth's climate. Before the mid-1960s, geoscientists thought our climate could change only relatively slowly, on timescales of thousands of years or longer. But new evidence from ice and sediment cores showed that idea was wrong.
The history of the scientific discovery of climate change began in the early 19th century when ice ages and other natural changes in paleoclimate were first suspected and the natural greenhouse effect was first identified.
The 1992 IPCC Supplement - Scientific Assessment. Download (1.1 MB) 5. Section A - Greenhouse Gases (title page) Download (29 KB) 6. ... The Intergovernmental Panel on Climate Change (IPCC) is active socially - choose your network: Engage with the IPCC. There are many ways to be involved and participate in the IPCC world.
Scientific evidence continues to show that human activities ( primarily the human burning of fossil fuels) have warmed Earth's surface and its ocean basins, which in turn have continued to impact Earth's climate. This is based on over a century of scientific evidence forming the structural backbone of today's civilization.
EPA research improves knowledge of the impacts of climate change on human health and the environment. This scientific information along with tools developed by EPA researchers can be used by communities to effectively, equitably and sustainably tackle the climate crisis. 2020s
Climate Change: The IPCC 1990 and 1992 Assessments IPCC First Assessment Report Overview and Policymaker Summaries and 1992 IPCC Supplement. Published with the support of Australia, Canada, Germany, The Netherlands, Spain,United States of America, Austria, France, Japan, Norway and United Kingdom. Printed in Canada 178 pp.
1992 - At the Earth Summit in Rio de Janeiro, governments agree the United Framework Convention on Climate Change. Its key objective is "stabilization of greenhouse gas concentrations in the...
One year later, in 1989, the Intergovernmental Panel on Climate Change (IPCC) was established under the United Nations to provide a scientific view of climate change and its political and...
@misc{etde_7015377, title = {Climate change 1992. The supplementary report to the IPCC scientific assessment} author = {Houghton, J T, Callender, B A, and Varney, S K} abstractNote = {This document reports the results of the short-term workplan of working group I and updates the 1990 IPCC scientific assessment. The major conclusions have not been altered but there a number of significant new ...
Warning. We the undersigned, senior members of the world's scientific community, hereby warn all humanity of what lies ahead. A great change in our stewardship of the earth and the life on it is required, if vast human misery is to be avoided and our global home on this planet is not to be irretrievably mutilated.
The scientific consensus that climate change is happening and that it is human-caused is strong. Scientific investigation of global warming began in the 19th century, and by the early 2000s, this research began to coalesce into confidence about the reality, causes, and general range of adverse effects of global warming.This conclusion was drawn from studying air and ocean temperatures, the ...
This update takes account of the latest significant scientific developments in the observation and modeling of climate and climate change. The material has been contributed by leading scientists from around the world and this update will become an essential reference companion to the 1990 IPCC Report, Climate Change edited by John Houghton et al.
Within a week, an international group of scientists had analyzed this extreme heat and concluded it would have been virtually impossible without climate change caused by humans. The planet's...
1938 - Proof that global temperatures are rising. A little-known amateur scientist called Guy Callendar makes history by discovering the planet has warmed. In 1938, steam engineer Callendar decided to take a break from his day job and began painstakingly collecting records from 147 weather stations across the world.
And last month, a new scientific review concluded that more than 99% of peer-reviewed scientific papers published between 2012 and 2020 find that climate change is mainly caused by humans. For the latest study, researchers began by selecting a random set of 3,000 scientific studies related to climate change published since 2012.
Global mean sea level has risen about 8-9 inches (21-24 centimeters) since 1880. The rising water level is mostly due to a combination of melt water from glaciers and ice sheets and thermal expansion of seawater as it warms. In 2021, global mean sea level was 97 millimeters (3.8 inches) above 1993 levels, making it the highest annual ...