1824: French scientist Jean-Baptiste
Fourier describes the greenhouse effect: how the atmosphere traps solar
energy to increase earth's surface temperature.
1859: Irish scientist John Tyndall
performs experiments that identify water vapor and carbon dioxide as
1896: Swedish chemist Svante Arrhenius
describes how burning fossil fuels produces carbon dioxide -- the first
suggestion that human activity produces greenhouse gasses.
1958: U.S. Scientist Charles Keeling
makes the first direct measurement of atmospheric carbon dioxide at
Mauna Loa in Hawaii; he discovers a yearly rise in atmospheric carbon
1979: A landmark report by National
Academy of Sciences connects the greenhouse effect to global warming.
The report warns that "a wait and see policy may mean waiting until
it's too late."
1988: The United Nations Environment
Program creates the Intergovernmental Panel on Climate Change and the
World Meteorological Organization to vet scientific knowledge of global
1990: The first IPCC report says that
levels of manmade greenhouse gases are increasing, and that this will
cause global warming. It documents a 0.3- to 0.6-degree Celsius increase
in average temperatures over the past 100 years.
June 1992: The U.N. Conference on the
Environment in Rio de Janeiro creates the U.N. Framework Convention
on Climate Change. Representatives from 178 nations attend. Two dozen
industrialized nations sign an accord requiring them to submit reports
describing policies for reducing emissions to 1990 levels.
March 1995: U.N. Framework Convention
on Climate Change Conference of Parties meets for first time in Berlin.
Delegates from 170 nations approve a plan called the Berlin mandate
to set specific targets for reducing emissions in the 21st century. They also accept a principle of "joint implementation"
in which industrialized countries offset emissions by financing cuts
in greenhouse gasses in developing countries.
1995: The second IPCC assessment is
released. It notes a 10 to 25 cm rise in sea levels over past decade,
and says that variations in global temperature suggest "a discernible
human influence on global climate."
July 1996: U.S. Undersecretary of State
for Global Affairs Timothy Wirth outlines a proposal at the UNFCC conference
in Geneva that calls for legally binding benchmarks for industrialized
nations for greenhouse gas reductions.
Dec. 1997: The Kyoto Protocol is adopted at the third Conference of Parties in Kyoto. The U.S. does not sign
the treaty. The treaty requires developed countries to reduce their
greenhouse gas emissions below specific levels between 2008 and 2012;
the cuts add up to a total of at least 5 percent below 1990 levels.
The U.S. would be required to reduce emissions by 7 percent, Europe
by 8 percent, Japan by 6 percent. Fleshing out the treaty is left to
Nov. 1998: Negotiators from 160 countries
agree to set rules for enforcing Kyoto protocol by late 2000.
Nov. 2000: A two-week conference at
the Hague fails to produce an agreement on measures to fight global
warming. The U.S. and EU cannot agree on necessary measures.
Nov. 2001: Negotiators from 160 countries
agree on a treaty strengthening Kyoto by setting mandatory emissions
reduction targets and establishing an enforcement mechanism. The treaty
requires 40 industrialized countries to reduce emissions by 5.2 percent below 1990 levels by 2012. The U.S. again doesn't sign.
2001: The IPCC's third report is issued.
It declares evidence for manmade global warming "incontrovertible"
although the effects on climate are hard to pin down. It also
states that the 1990s were the warmest decade since records have been
kept. (Cosmos, Frontline)
2002: On the Antarctic peninsula, the
Larsen B ice shelf -- bigger than Rhode Island -- collapses into the
2003: A deadly summer heat wave in
Europe kills more than 30,000 people
2004: The International Energy Agency
says China is now the worlds' second-biggest greenhouse gas emitter after the U.S.
Nov 2004: After Russia ratifies the
Kyoto treaty -- the 19th country to do so -- the treaty becomes
Feb. 2005: The Kyoto Protocol takes
2005: Awareness and concern about global
warming rises in the U.S. after a tough storm season, including Katrina.
Dec. 2005: Industrialized nations that
are part of Kyoto agree to set talks to produce a new set of binding
limits to take effect in 2012, after Kyoto expires.
2006: Former Vice President Al Gore's
documentary "An Inconvenient Truth" is released.
2006: California adopts a plan to reduce
greenhouse gas emissions to 1990 levels by 2020. The state files
a lawsuit against six carmakers for contributions to global warming.
2006: NASA's top climatologist, James
Hansen, accuses the Bush administration of censoring what he can say
about climate change.
2007: China surpasses the U.S. in greenhouse
Feb. 2007: An IPCC report says that
it is extremely likely that human activities are contributing to global
warming in a way that will be difficult to reverse.
April 2007: An IPCC report says with "high confidence" that human activities are responsible for
global warming and that the warming is changing the ecosystem and plant
and animal behavior.
May 2007: An IPCC report says that the world needs to significantly cut greenhouse gasses, and offers measures
for doing so.
Oct. 2007: Al Gore and the IPCC share
the 2007 Nobel Peace Prize for efforts to spread awareness of climate
Nov. 2007: The IPCC releases final
assessment paper. Report finds that the world will have to end its growth
of carbon emissions within seven years and become free of carbon-emitting
technologies in four decades to avoid widespread extinctions, flooding,
loss of wetlands, deaths from heat waves, and other consequences.
December 2007: The conference of parties
to the UNFCCC meets in Bali, Indonesia, to launch negotiations for a
roadmap for a new post-Kyoto climate change treaty. After much anger
directed at the U.S., negotiators cut a last-minute deal and agree to
negotiate a treaty by December 2009.
2008: A 160-square-mile section of
the Wilkins Ice Shelf breaks from the coast of Antarctica.
April 2008: Negotiators in Bangkok,
Thailand, begin the first formal talks after the Bali conference to
negotiate a new climate treaty.
December 2009: Scheduled date for the
15th annual conference of the parties to the UNFCCC. Due
date to negotiate a new climate change treaty.