Climate Change Timeline : Stephen Kovach

1800-1870

Level of carbon dioxide gas (CO2) in the atmosphere, as later measured in ancient ice, is about 290 ppm (parts per million).

Mean global temperature (1850-1890) is roughly 13.6°C.

First Industrial Revolution. Coal, railroads, and land clearing speed up greenhouse gas emission, while better agriculture and sanitation speed up population growth.

1824

Fourier calculates that the Earth would be colder if it lacked an atmosphere.

1859

Tyndall demonstrates that some gases block infrared radiation, and notes that changes in the concentration of the gases could bring climate change.

1879

International Meteorological Organization begins to compile and standardize global weather data, including temperature.

1800-1870

Level of carbon dioxide gas (CO2) in the atmosphere, as later measured in ancient ice, is about 290 ppm (parts per million).

Mean global temperature (1850-1890) is roughly 13.6°C.

First Industrial Revolution. Coal, railroads, and land clearing speed up greenhouse gas emission, while better agriculture and sanitation speed up population growth.

1897

Chamberlin produces a model for global carbon exchange including feedbacks.

1870-1910

Second Industrial Revolution. Fertilizers and other chemicals, electricity, and public health further accelerate growth.

1920-1925

Opening of Texas and Persian Gulf oil fields inaugurates era of cheap energy.

1930s - Global warming trend since late 19th century reported.

1938

Callendar argues that CO2 greenhouse global warming is underway, reviving interest in the question.

1955

Phillips produces a convincing computer model of the global atmosphere. =>Models (GCMs)

1956

Ewing and Donn offer a feedback model for abrupt climate change.

1958

Telescope studies show a greenhouse effect raises temperature of the atmosphere of Venus far above the boiling point of water.

1960

Mitchell reports downturn of global temperatures since the early 1940s

1960

Keeling accurately measures CO2 in the Earth’s atmosphere and detects an annual rise.

The CO2 level is 315 ppm. Mean global temperature (five-year average) is 13.9°C.

1963

Calculations suggest that feedback with water vapor could make the climate acutely sensitive to changes in CO2 level.

First meeting of experts concerned with global warming warns that a rise in sea level is likely, with “immense flooding” of shorelines.

1965

Boulder, Colorado meeting on causes of climate change: Lorenz and others point out the chaotic nature of the climate system and the possibility of sudden shifts.

1966

Emiliani’s analysis of deep-sea cores and Broecker’s analysis of ancient corals show that the timing of ice ages was set by small orbital shifts, suggesting that the climate system is sensitive to small perturbations.

1968

Studies suggest a possibility of collapse of Antarctic ice sheets, which would raise sea levels catastrophically.

1969

Budyko and Sellers present models of catastrophic ice-albedo feedbacks.

Nimbus III satellite begins to provide comprehensive global atmospheric temperature measurements. =>Government

1970

First Earth Day. Environmental movement attains strong influence, spreads concern about global degradation.

1972

Ice cores and other evidence show big climate shifts in the past between relatively stable modes in the space of a thousand years or so, especially around 11,000 years ago.

1972: Droughts in Africa, Ukraine, India cause world food crisis, spreading fears about climate change.

1974

Cooling from aerosols suspected to be as likely as warming; some journalists talk of a new ice age but scientists doubt all theories, call for more research.

1975

Warnings about environmental effects of airplanes lead to investigations of trace gases in the stratosphere and discovery of danger to ozone layer.

Manabe and collaborators produce complex but plausible computer models which show a temperature rise of a few degrees for doubled CO2.

1976

Studies show that CFCs (1975) and also methane and ozone (1976) can make a serious contribution to the greenhouse effect.

Deep-sea cores show a dominating influence from 100,000-year Milankovitch orbital changes, emphasizing the role of feedbacks.

Deforestation and other ecosystem changes are recognized as major factors in the future of the climate.

Eddy shows that there were prolonged periods without sunspots in past centuries, corresponding to cold periods.

1979: US National Academy of Sciences report finds it highly credible that doubling CO2 will bring 1.5-4.5°C global warming

1979

Second oil “energy crisis.” Strengthened environmental movement encourages renewable energy sources, inhibits nuclear energy growth.

1981

Hansen and others show that sulfate aerosols can significantly cool the climate, raising confidence in models that incorporate aerosols and show future greenhouse warming.

1981

Some scientists predict greenhouse warming “signal” should become visible around the year 2000.

1982

Greenland ice cores reveal drastic temperature oscillations in the space of a century in the distant past.

1982: Strong global warming since mid-1970s is reported, with 1981 the warmest year on record.

1983

Reports from US National Academy of Sciences and Environmental Protection Agency spark conflict; greenhouse warming becomes a factor in mainstream politics.

1983

Speculation over catastrophic climate change following a nuclear war, or a dinosaur-killing asteroid strike, promote realization of the atmosphere’s fragility.

1985

Ramanathan and collaborators announce that global warming may come twice as fast as expected, from rise of methane and other trace greenhouse gases.

Villach Conference declares consensus among experts that some global warming seems inevitable, calls on governments to consider international agreements to restrict emissions.

Antarctic ice cores show that CO2 and temperature went up and down together through past ice ages, pointing to powerful feedbacks.

Broecker speculates that a reorganization of North Atlantic Ocean circulation can bring swift and radical climate change.

1986: Meltdown of reactor at Chernobyl (Soviet Union) cripples plans to replace fossil fuels with nuclear power.

1987

Montreal Protocol of the Vienna Convention imposes international restrictions on emission of ozone-destroying gases.

1988

News media coverage of global warming leaps upward following record heat and droughts plus statements by Hansen.

Toronto conference calls for strict, specific limits on greenhouse gas emissions; UK Prime Minister Thatcher is first major leader to call for action.

Ice-core and biology studies confirm living ecosystems give climate feedback by way of methane, which could accelerate global warming.

Intergovernmental Panel on Climate Change (IPCC) is established.

1990

Fossil-fuel and other U.S. industries form Global Climate Coalition to persuade politicians and the public that climate science is too uncertain to justify action.

1991

Mt. Pinatubo explodes; Hansen predicts cooling pattern, verifying (by 1995) computer models of aerosol effects.

1991

Global warming skeptics claim that 20th-century temperature changes followed from solar influences. (The solar-climate correlation would fail in the following decade.)

1991: Geologists discover massive extinction event 55 million years ago, associated with tremendous warming caused by increase in greenhouse gases. =>Rapid change

1992

Conference in Rio de Janeiro produces UN Framework Convention on Climate Change, but US blocks calls for serious action.

Study of ancient climates reveals climate sensitivity to CO2 in same range as predicted independently by computer models.

Experience

Experience