Timeline: How the world discovered global warming

Fri Dec 2, 2011 8:53am EST

Greenpeace activists hold cutouts portraying extreme weather caused by climate change during a demonstration in front of the United Nations building, venue of this year's climate talks, in Bangkok April 4, 2011. REUTERS/Chaiwat Subprasom

Greenpeace activists hold cutouts portraying extreme weather caused by climate change during a demonstration in front of the United Nations building, venue of this year's climate talks, in Bangkok April 4, 2011.

Credit: Reuters/Chaiwat Subprasom

(Reuters) - U.N. climate talks in Durban, South Africa, from November 28-December 9 are aimed at agreeing new measures to stem rising emissions of planet-warming greenhouse gases.

Following is a look at how the world discovered global warming and international steps to try to address it:

300 BC - Theophrastus, a student of Greek philosopher Aristotle, documents that human activity can affect climate. He observes that drainage of marshes cools an area around Thessaly and that clearing of forests near Philippi warms the climate.

17th century - Flemish scientist Jan Baptista van Helmont discovers that carbon dioxide is given off by burning charcoal.

18th century - The Industrial Revolution starts, bringing rising use of fossil fuels.

1820s - French mathematician Jean-Baptiste Joseph Fourier suggests something in the atmosphere is keeping the world warmer than it would otherwise be, a hint at the greenhouse effect.

1830s - Swiss naturalist Louis Agassiz presents evidence of past changes in Alpine glaciers, pointing to ancient Ice Ages and showing that the climate has not always been stable.

1860s - Irish scientist John Tyndall shows that molecules of gases such as water vapour and carbon dioxide trap heat. He wrote that changes "could have produced all the mutations of climate which the researches of geologists reveal."

1896 - Swedish chemist Svante Arrhenius becomes the first to quantify carbon dioxide's role in keeping the planet warm. He later concluded that burning of coal could cause a "noticeable increase" in carbon levels over centuries.

1950s - U.S. scientist Charles Keeling sets up stations to measure carbon dioxide concentrations in the atmosphere at the South Pole and at Mauna Loa, Hawaii. The measurements have shown a steady rise.

1965 - U.S. President Lyndon Johnson tells Congress: "This generation has altered the composition of the atmosphere on a global scale through ... a steady increase in carbon dioxide from the burning of fossil fuels."

1988 - British Prime Minister Margaret Thatcher tells the United Nations: "The problem of global climate change is one that affects us all and action will only be effective if it is taken at the international level. It is no good squabbling over who is responsible or who should pay."

1988 - The United Nations sets up the Intergovernmental Panel on Climate Change (IPCC) to assess the scientific evidence.

1992 - World leaders agree the U.N. Framework Convention on Climate Change, which sets a non-binding goal of stabilising greenhouse gas emissions by 2000 at 1990 levels, a target not met overall.

1995 - The IPCC concludes for the first time that humans are causing global warming, saying: "The balance of evidence suggests a discernible human influence on global climate."

1997 - The Kyoto Protocol is agreed in Japan; developed nations agree to cut their greenhouse gas emissions on average by at least 5 percent below 1990 levels by 2008-12. The United States stays out of the deal.

2001 - The IPCC concludes it is "likely," or at least 66 percent probable, that human activities are the main cause of recent warming.

2001 - President George W. Bush notes the U.S. National Academy of Sciences says greenhouse gases are rising "in large part due to human activity." He adds: "Yet, the Academy's report tells us that we do not know how much effect natural fluctuations in climate may have had on warming. We do not know how much our climate could, or will change in the future."

2007 - The IPCC says it is "very likely," at least 90 percent certain, that humans are to blame for most of the observed warming trend of the past 50 years. It also said warming of the planet was "unequivocal."

2009 - A conference of 193 countries agree in December to "take note" of a new Copenhagen Accord to fight climate change, after U.N. talks in Denmark. The accord is not legally binding and does not commit countries to agree a binding successor to the Kyoto Protocol when its first stage ends in 2012. The conference did recognize "the scientific view that the increase in global temperature should be below 2 degrees Celsius" and "deep cuts in global emissions are required."

2010 - A deal among 190 nations to slow climate change throws a lifeline to U.N.-led talks.

2011 - More than 190 nations meet in Durban, South Africa, to try to agree what to do after the first stage of the Kyoto Protocol expires in 2012 and on a Green Climate Fund to channel billions of dollars to poorer nations to green their economies and help them protect against the effects of climate change.

(Sources: Reuters/Intergovernmental Panel on Climate Change, "Why We Disagree about Climate Change" -- book by Mike Hulme, founding director of the Tyndall Center, Margaret Thatcher Foundation, Lyndon Baines Johnson Library and Museum, Svante Arrhenius writings)

(Writing by Alister Doyle, David Fogarty and David Cutler, London Editorial Reference Unit)

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Comments (2)
Parker1227 wrote:
The 2009 Climategate scandal just got worse with a new email release confirming grotesque maleficence within a small group of leading climate experts in England and the US.

Google – Climategate 2

These so-called scientists are shown arguing by email about how to hide unfavourable temperature trends, massage historical data to make the warming of 1980-2000 look more unusual than it was, conspiring to destroy government data (delete emails) and fend off FOI requests, and trying to destroy the reputations of scientists who dared disagree with them.

It is a huge scandal which will rock science for a generation, and the press has colluded with these dishonest “cause driven” enviro-hacks to try to ignore/hide the whole thing.

Shameful all around.

BTW The Arctic ice goes through multi-decadal cycles of melt back. Changes in ocean currents, and a multitude of other natural factors have been linked to this natural cycle.

Man may be causing some of the melting, but anyone who claims to really know how much, is not an honest scientist.

It is an extremely complex and new science. Their computer models have been abject failures in predicting real climate changes.

Dec 03, 2011 11:33pm EST  --  Report as abuse
borisjimbo wrote:
Oh, are you saying that you are an “honest scientist”, Parker1227?

Dec 04, 2011 1:07am EST  --  Report as abuse
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