A striking sense of shared purpose marks the first UN environmental conference, held in Stockholm. From the unusually smooth negotiations emerges a declaration that many of the planet's problems — particularly degradation of oceans and the atmosphere — will need international policy solutions. A separate action plan includes the general recommendation "that Governments be mindful of activities in which there is an appreciable risk of effects on climate." A new agency, the UN Environmental Programme, is tasked with coordinating these efforts. (See Politics, bureaucracy and the environment - PDF)
1979
Science panels preview warming
Scientists worldwide meet in Geneva to preview possible impacts of climate change at the First World Climate Conference in February. The researchers urge the world's governments "to foresee and prevent potential man-made changes in climate that might be adverse to the well-being of humanity." (See World climate conference turns to the weather - PDF)
In July, a US National Academy of Sciences climate report ordered by the Carter administration offers a comprehensive look at the threat of global warming. Studying the question "If it were indeed certain that atmospheric carbon dioxide would increase on a known schedule, how well could we project the climatic consequences?", the Academy's panel envisages a global temperature increase of 1.5-4.5 °C by the mid-twenty-first century. "A wait-and-see policy may mean waiting until it is too late," their report warns.
Image: MSLIGHTBOX, ISTOCKPHOTO
1985
Warning from Villach
In Villach, Austria, researchers from 29 countries spell out a scientific consensus on the greenhouse effect — and sound a clear warning to policymakers. They declare, "As a result of the increasing concentrations of greenhouse gases, it is now believed that in the first half of the next century a rise of global mean temperature could occur which is greater than any in man's history." Their statement also notes that "the rate and degree of future warming could be profoundly affected by governmental policies on energy conservation, use of fossil fuels, and the emission of some greenhouse gases." While avoiding making recommendations on energy issues, they caution world leaders against assuming a stable climate in long-term plans. For ongoing updates on climate science, the UN agencies sponsoring the conference create a small, elite committee of experts, the Advisory Group on Greenhouse Gases (AGGG).
Image: Villach / JOHANN JARITZ
1988
June - Political breakthroughs
As US senators swelter in a record heat wave, NASA climatologist James Hansen tells them that the year's global temperatures are unprecedented in the instrumental record. "There is only a one per cent chance of an accidental warming of this magnitude," he claims. "The greenhouse effect has been detected, and it is changing our climate now." Though some heavyweight scientists say Hansen's landmark testimony is too extreme, the Senate hearings draw widespread news coverage.
The Toronto Conference on the Changing Atmosphere, convening days after Hansen's testimony and a year after the adoption of the Montreal Protocol to protect the Earth's ozone layer, becomes the first to set specific climate policy targets — even though it's a scientific meeting. Researchers echo the US National Academy's conclusion that the world could warm 1.5-4.5 °C by 2050 and call on governments to reduce emissions to 20 per cent below their 1988 levels by 2005 and to cut them by 50 per cent thereafter. (See Canada's high hopes - PDF)
Image: Hansen testifies in the Senate / KAVEH SARDARI, WORLDWATCH INSTITUTE
November - IPCC established
The UN sets up the Intergovernmental Panel on Climate Change (IPCC), a massive scientific advisory body that replaces the AGGG. Most of the world's climate experts will contribute to its twice-a-decade reports on the scientific understanding of climate change and its implications. 'Intergovernmental' is an organizing keyword: officials and experts drawn from government institutions worldwide oversee the IPCC's activities, and all participating governments vet its assessment reports line by line before publication. The cautious conclusions that result are seen as authoritative, and the periodic reports funnel information into succeeding rounds of UN climate policy talks. (See Government action needed to mitigate 'greenhouse effect' - PDF)
Image: Bert Bolin, first IPCC chairman / IPCC SECRETARIAT
1990
IPCC consensus, but no global deal
The IPCC's first assessment report concludes that unabated human greenhouse emissions are certain to cause global warming. The panel also warns that 'business as usual' will most likely raise average temperatures 0.3 °C per decade, with 65-centimetre sea-level rises swamping coasts and islands by 2100. The scientists estimate that the planet has already warmed 0.3-0.6 °C in the past century but say they are uncertain whether this is as a result of human activity or of natural variability. "The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more," states their summary. The working group on mitigation advises that only an immediate reduction of more than 60 per cent in greenhouse emissions would prevent concentrations of the gases from rising above their 1990 levels. (See Towards a greenhouse treaty? - PDF)
Joining the IPCC's stark predictions are policy studies from western Europe, Japan, Australia and New Zealand that say efficiency measures could level off greenhouse gas emissions, and eventually reduce them, at no net economic cost. These countries hope to get the United States on board for emissions cuts at the Second World Climate Conference, held in Geneva that November. A meeting of 747 scientists and experts in the conference's first half backs action against climate threats despite the remaining scientific questions. The ministerial sessions that follow, however, run into high tensions over targets. Though many rich nations individually pledge to reduce their greenhouse gas production, President George H. W. Bush's US delegation — along with those of major oil exporters such as the USSR — insist it is too soon to commit, arguing that both climate change science and emissions projections remain uncertain. The next chance for international targets is a new UN climate treaty to be finished in 1992. Negotiations begin in December in New York. (See Two declarations at odds - PDF)
Image: UN building, New York / ZINCHICK, ISTOCKPHOTO
1992
Rio Earth Summit celebrates UNFCCC treaty
Completed in New York in May, the UN Framework Convention on Climate Change (UNFCCC) commits signatories to a long-term goal of stabilizing atmospheric greenhouse gases "at a level that would prevent dangerous anthropogenic interference with the climate system." Specifically, it endorses a proposal by the European Community that developed nations stabilize their year-2000 greenhouse gas emissions at 1990 levels. Because the United States still refuses to accept mandatory limits, this target is made voluntary.
Signing opens with fanfare at the Rio Earth Summit in June, the largest gathering of world leaders to date. As governments set about ratifying the 2000 target — which many will later fail to meet — the globe is cooling slightly in the aftermath of Mount Pinatubo's eruption in 1991. (See Between Stockholm and Rio - PDF)
Image: Brazilian President Fernando Collor de Mello signs the UNFCCC / EDUARDO DIBAIA, AP/PA PHOTOS
1994
UNFCCC enters into force
1995
New policy mandate, new IPCC report
In April, the first meeting of the UNFCCC Conference of Parties affirms that the 1992 Convention's hard-won 2000 target is only a small first step. The 'Berlin Mandate' (PDF) launches two years of negotiations on what will become the Kyoto Protocol, an agreement on post-2000 greenhouse gas reductions. (See Meeting agrees on need for new targets for greenhouse gas emissions - PDF)
Berlin's "signature item", according to the head of the US delegation, is approval of a trading mechanism that enables signatory developed countries to officially cancel out their own rising emissions by funding improvements that lower greenhouse gas levels in the developing world. Global patterns of industrialization are changing — a 1995 study sees China as the world's largest emitter in 2020 — and some wealthy nations feel more comfortable leading on cuts if they don't have to make them within their own borders.
The IPCC's second assessment report (PDF), released in the fall, concludes that twentieth-century warming is "unlikely to be entirely natural in origin". However, new climate models that include atmospheric aerosols — like those spewed by Pinatubo — tone down the projections of future warming made in the 1990 assessment. Unabated emissions are thought to yield 1-3.5 °C of global warming by 2100, with best estimates of 2 °C of warming and 50 centimetres of sea-level rise over the twenty-first century. Under such scenarios, many regions would suffer floods, droughts, fires and pest outbreaks, the panel says. (See Climate report cuts call for strong policies - PDF)
Image: Smog over Beijing / JOHNIE LEE
1996
Preparing to cut carbon
Global carbon dioxide emissions, which remained relatively flat in the early 1990s, have begun to climb again, and scientists warn policymakers that more stringent cuts are needed to reach the targets set in Rio. Parties to the UNFCCC meet a second time in Geneva, where they endorse the new IPCC report. The US team, under new leadership from the Clinton presidential administration, now urges legally binding targets, and the conference adopts this goal. (See Meeting warms to binding climate agreement - PDF)
Image: Global carbon dioxide emissions from fossil fuels (megatonnes) reported in International Energy Annual 2005
1997
Tentative success in Kyoto
Officials arriving in Kyoto, Japan, in December have ten days to finalize a binding global climate treaty for the new millennium. With the United States refusing to reduce emissions below 1990 levels and the European Union asking for a 15 per cent cut on 1990 levels, another standoff at first looks likely. But a visit from US Vice President Al Gore introduces enough flexibility to allow a compromise. In the Kyoto Protocol, rich nations adopt legally binding individual targets for 2008-2012 that sum to a 5.2 per cent reduction on 1990 levels of six greenhouse gases.
But the final session runs all night and into an unscheduled extra day amid disagreements over how greenhouse gas cuts can be fairly apportioned between industrialized and developing nations. Detailed decisions on the issue are postponed to the next UNFCCC conference the following year. (See Kyoto agreement creates new agenda for climate research)
Image: Al Gore delivers an opening speech at Kyoto / KATSUMI KASAHARA, AP/PA Photos
At the conference set to finalize the Kyoto Protocol, the European Union and the United States reach a stalemate over whether nations should be allowed to offset their emissions using, for example, carbon credits from forestry. A last-minute compromise agreed between the US and UK is rejected by other European countries, and the meeting closes without a deal. (See Deadlock in The Hague, but hopes remain for spring climate deal)
Image: Head US delegate Frank Loy hit with a pie by a protester / REUTERS
2001
January - IPCC darkens the picture
The IPCC's third assessment report (PDF) highlights "new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities". The science suggests it is very likely that the 1990s were the hottest decade and 1998 the hottest year since measurements began in 1861. Telltale effects of a warming world such as melting glaciers and shifting species ranges become more apparent.
The outlook for the next century is grimmer than in 1995: the panel now projects warming of 1.4-5.8 °C by 2100. Ironically, the anticipated rise in temperature is partly a result of pollution-control schemes to reduce atmospheric levels of sulfur dioxide, an ozone-depleting and climate-cooling chemical, belched out by tailpipes and smokestacks. The report raises the possibility of sudden shocks to the Earth system, such as a slowdown of ocean circulation, and paints in new details of a capricious future climate with more heat waves and other extreme events. (See Assessment ups the ante on climate change)
Image: The 2001 report's landmark 'hockey stick' graph of Northern Hemisphere temperatures, based on work by Michael Mann and co-authors published in 1998 and 1999
Red, thermometer data; blue, estimates from tree rings, corals, ice cores and historical records; gray, error ranges / IPCC (modified and based on Figure 1, "Summary for Policymakers", Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge Univ. Press, 2001)
November - Kyoto finalized, minus the US
US officials announce in March that the new president, George W. Bush, has "no interest" in implementing the Kyoto Protocol, which he calls "fatally flawed" in a June speech. The treaty demands too little of rapidly developing countries, and complying with it would threaten the nation's economy, argues the White House. This leaves the United States on the sidelines at UN meetings in Bonn, Germany, in July and Marrakesh, Morocco, in November.
After the now customary marathon negotiations, more than 160 other Kyoto signatories settle the problems from the Hague and write most of the treaty's final rules. In the end, the Protocol allows effectively unlimited emissions offsets. (See Accord in Morocco breathes fresh life into Kyoto Protocol)
Image: Bush gives a press conference on energy in July / ERIC DRAPER, WHITE HOUSE
2002
Russia hesitates
The Kyoto Protocol's fine print says it can come into force only once it is ratified by 55 countries, including wealthy nations responsible for 55 per cent of the developed world's 1990 carbon dioxide emissions. With the United States — and its 36.1 per cent slice of developed-world carbon dioxide — out of the picture and Australia also refusing ratification, other signatories are urged to move forward so that the policy can begin to take effect. The European Union and Japan quickly ratify, but Russia balks, telling a New Delhi meeting in October that the government needs more time to think it over. The delay stalls enforcement of the Protocol, and the New Delhi talks place a fresh focus on adapting to climate impacts that are increasingly seen as inevitable.
Image: 1990 carbon emissions from developed-world Kyoto parties
Red, ratified by October 2002; green, ratified by November 2004; yellow, ratified later; blue, awaiting ratification
2004
Kyoto ratified
After the scorching summer of 2003, which broke temperature records across Europe and killed thousands, political will for emissions cuts warms up. The Russian government grudgingly ratifies the Kyoto protocol in November 2004, while seeking EU support for Russia's membership in the World Trade Organization. The Protocol can now come into force in February 2005. (See Russia backs Kyoto treaty)
Image: Activists urge Russia to ratify / PIERRE GLEIZES, GREENPEACE
The Montreal Accord, agreed at 6:17 AM after weathering a walkout by the head US delegate, defines two parallel tracks for future climate talks. Nations committed to Kyoto targets are to start negotiating a successor (PDF) to replace the Protocol when it expires in 2012, and many hope the United States will join this new treaty after Bush leaves office in 2009. For now, though, a larger group of countries including the US and China say they will take their cue from the voluntary targets of the 1992 UNFCCC and discuss "open and unbinding" emissions cuts (PDF), without initiating "any negotiations leading to new commitments". (See Post-Kyoto pact: shaping the successor)
Image: New Orleans / NOAA
2006
The world's greatest market failure
Former World Bank chief economist Sir Nicholas Stern delivers a report on the economics of climate change to the UK government. Calling climate change the greatest and widest-ranging market failure ever seen, Stern sums up the likely costs of various policy options and prescribes how to minimize the social and economic impacts of future warming. (See Economic review counts costs of climate change)
Image: MAIKID, ISTOCKPHOTO
2007
October - Nobel and new report for IPCC
The IPCC and Al Gore share the year's Nobel Peace Prize for "their efforts to build up and disseminate knowledge about man-made climate change." The prize follows an Oscar for Gore's 2006 climate documentary An Inconvenient Truth and adds further gravitas to the Panel's latest and most daunting report (PDF).
It's now 90 per cent certain that humans are to blame for recent global warming, says the IPCC, compared to the 66-per-cent certainty stated in 2001. And new worries about feedback effects of future warming make the worst-case scenario even more foreboding: projected temperature rise by 2100 is likely to be between 1.8 °C and 4 °C, though increases as large as 6.4 °C are possible. Potential consequences are spelled out continent by continent — and degree by degree of warming. (See Climate report released)
Image: Al Gore and IPCC Chairman Rajendra Pachauri at the Nobel ceremony / ODD ANDERSEN, AP/PA PHOTOS
December - Post-Kyoto roadmap set in Bali
Yielding at last to international pressure, the United States comes back to the table at a major UN conference on post-Kyoto climate policy held in Bali, Indonesia. Australia's newly elected government kicks off the meeting by ratifying Kyoto, leaving the US the only industrialized country to reject the Protocol.
Despite the Bush administration posing a major impediment to progress during the talks, at the end of a gruelling two weeks marked by heated arguments, threats of trade sanctions or boycotts, and even tears, a deal is reached (PDF).
The cost of bringing in the US, however, is an agreement that hides away science-based emissions targets. The European Union in March promised a 20 per cent cut on 1990 emissions levels by 2020, and a September UN conference in Vienna, working from the IPCC's warnings, recommended that developed countries deepen this medium-term cut to a level of 25-40 per cent. But the US won't stand for any such numbers in the Bali agreement, so the targets are replaced by a footnote referencing IPCC findings. The Bali Action Plan sketches a two-year 'roadmap' for negotiating a successor to Kyoto, to be finalized in Copenhagen in December 2009. (See Was the science sidelined in Bali?)
Image: Cutting the cake for Kyoto's tenth anniversary at Bali / JAN GOLINSKI, UNFCCC
2008
Slow going on the road to Copenhagen
In April, Bangkok hosts the next conference on the Bali roadmap. Though the meeting's goal is merely to set a timetable for future meetings, eleventh-hour struggles drain the delegates once again. 'Sectoral' approaches to emissions cuts, which would push selected industries to reduce their greenhouse gases, gain attention thanks to a campaign by Japan. But developing nations led by China — now the world's top emitter, having surpassed the United States in 2007 — continue to resist the commitments these approaches would impose. More tug-of-war looks likely at the upcoming UN meeting in Poznan, Poland, in December. (See Post-Bali paradox at UN meeting in Bangkok)
The G8 summit in Hokkaido, Japan, in July gives the biggest emitters a chance to move forward in parallel with the UN meetings. The eight nations, including the US, commit to a vision of halving global emissions by 2050 — apparently an improvement on the 2007 G8 pledge to "seriously consider" a similar-sounding target. But whereas the 2007 statement specified that the 50 per cent drop would start from 1990 levels, this time G8 leaders don't state the baseline year, and Japanese Prime Minister Fukuda insists targets would be measured against current emissions. Delegates also fail to set nearer-term goals despite pressure from UN officials, scientists and environmental groups to do so. (see Leaders still vague on emissions targets)
At a September meeting of the IPCC, the world's premier climate change oracle celebrates its twentieth birthday and looks to the future. Election of new leaders kicks off work on the next assessment report, due in six years. On the docket for discussion is how to respond to policymakers' requests for more timely, policy-motivated information that could feed UN talks leading up to Copenhagen and beyond.
Image: G8 leaders in Hokkaido / MINISTRY OF FOREIGN AFFAIRS OF JAPAN
2009
Deadline for 'Kyoto II'
To complete Kyoto's successor on schedule, delegates must sort out a lengthening list of divisive issues, some of which have barely budged in years. And there's little sign yet of a surge of activity after the galvanizing IPCC report and Bali conference in 2007. But past UN climate negotiations reveal a long habit of last-minute solutions, and most players expect the upcoming election of a new US president to greatly alter the field.
Image: Wind turbines off the coast of Copenhagen / PARETO, ISTOCKPHOTO
A striking sense of shared purpose marks the first UN environmental conference, held in Stockholm. From the unusually smooth negotiations emerges a declaration that many of the planet's problems — particularly degradation of oceans and the atmosphere — will need international policy solutions. A separate action plan includes the general recommendation "that Governments be mindful of activities in which there is an appreciable risk of effects on climate." A new agency, the UN Environmental Programme, is tasked with coordinating these efforts. (See Politics, bureaucracy and the environment - PDF)
Scientists worldwide meet in Geneva to preview possible impacts of climate change at the First World Climate Conference in February. The researchers urge the world's governments "to foresee and prevent potential man-made changes in climate that might be adverse to the well-being of humanity." (See World climate conference turns to the weather - PDF)
In Villach, Austria, researchers from 29 countries spell out a scientific consensus on the greenhouse effect — and sound a clear warning to policymakers. They declare, "As a result of the increasing concentrations of greenhouse gases, it is now believed that in the first half of the next century a rise of global mean temperature could occur which is greater than any in man's history." Their statement also notes that "the rate and degree of future warming could be profoundly affected by governmental policies on energy conservation, use of fossil fuels, and the emission of some greenhouse gases." While avoiding making recommendations on energy issues, they caution world leaders against assuming a stable climate in long-term plans. For ongoing updates on climate science, the UN agencies sponsoring the conference create a small, elite committee of experts, the Advisory Group on Greenhouse Gases (AGGG).
As US senators swelter in a record heat wave, NASA climatologist James Hansen tells them that the year's global temperatures are unprecedented in the instrumental record. "There is only a one per cent chance of an accidental warming of this magnitude," he claims. "The greenhouse effect has been detected, and it is changing our climate now." Though some heavyweight scientists say Hansen's landmark testimony is too extreme, the Senate hearings draw widespread news coverage.
The UN sets up the Intergovernmental Panel on Climate Change (IPCC), a massive scientific advisory body that replaces the AGGG. Most of the world's climate experts will contribute to its twice-a-decade reports on the scientific understanding of climate change and its implications. 'Intergovernmental' is an organizing keyword: officials and experts drawn from government institutions worldwide oversee the IPCC's activities, and all participating governments vet its assessment reports line by line before publication. The cautious conclusions that result are seen as authoritative, and the periodic reports funnel information into succeeding rounds of UN climate policy talks. (See Government action needed to mitigate 'greenhouse effect' - PDF)
The IPCC's first assessment report concludes that unabated human greenhouse emissions are certain to cause global warming. The panel also warns that 'business as usual' will most likely raise average temperatures 0.3 °C per decade, with 65-centimetre sea-level rises swamping coasts and islands by 2100. The scientists estimate that the planet has already warmed 0.3-0.6 °C in the past century but say they are uncertain whether this is as a result of human activity or of natural variability. "The unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more," states their summary. The working group on mitigation advises that only an immediate reduction of more than 60 per cent in greenhouse emissions would prevent concentrations of the gases from rising above their 1990 levels. (See Towards a greenhouse treaty? - PDF)
Completed in New York in May, the UN Framework Convention on Climate Change (UNFCCC) commits signatories to a long-term goal of stabilizing atmospheric greenhouse gases "at a level that would prevent dangerous anthropogenic interference with the climate system." Specifically, it endorses a proposal by the European Community that developed nations stabilize their year-2000 greenhouse gas emissions at 1990 levels. Because the United States still refuses to accept mandatory limits, this target is made voluntary.
In April, the first meeting of the UNFCCC Conference of Parties affirms that the 1992 Convention's hard-won 2000 target is only a small first step. The 'Berlin Mandate' (PDF) launches two years of negotiations on what will become the Kyoto Protocol, an agreement on post-2000 greenhouse gas reductions. (See Meeting agrees on need for new targets for greenhouse gas emissions - PDF)
Global carbon dioxide emissions, which remained relatively flat in the early 1990s, have begun to climb again, and scientists warn policymakers that more stringent cuts are needed to reach the targets set in Rio. Parties to the UNFCCC meet a second time in Geneva, where they endorse the new IPCC report. The US team, under new leadership from the Clinton presidential administration, now urges legally binding targets, and the conference adopts this goal. (See Meeting warms to binding climate agreement - PDF)
Officials arriving in Kyoto, Japan, in December have ten days to finalize a binding global climate treaty for the new millennium. With the United States refusing to reduce emissions below 1990 levels and the European Union asking for a 15 per cent cut on 1990 levels, another standoff at first looks likely. But a visit from US Vice President Al Gore introduces enough flexibility to allow a compromise. In the Kyoto Protocol, rich nations adopt legally binding individual targets for 2008-2012 that sum to a 5.2 per cent reduction on 1990 levels of six greenhouse gases.
At the conference set to finalize the Kyoto Protocol, the European Union and the United States reach a stalemate over whether nations should be allowed to offset their emissions using, for example, carbon credits from forestry. A last-minute compromise agreed between the US and UK is rejected by other European countries, and the meeting closes without a deal. (See Deadlock in The Hague, but hopes remain for spring climate deal)
The IPCC's third assessment report (PDF) highlights "new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities". The science suggests it is very likely that the 1990s were the hottest decade and 1998 the hottest year since measurements began in 1861. Telltale effects of a warming world such as melting glaciers and shifting species ranges become more apparent.
US officials announce in March that the new president, George W. Bush, has "no interest" in implementing the Kyoto Protocol, which he calls "fatally flawed" in a June speech. The treaty demands too little of rapidly developing countries, and complying with it would threaten the nation's economy, argues the White House. This leaves the United States on the sidelines at UN meetings in Bonn, Germany, in July and Marrakesh, Morocco, in November.
The Kyoto Protocol's fine print says it can come into force only once it is ratified by 55 countries, including wealthy nations responsible for 55 per cent of the developed world's 1990 carbon dioxide emissions. With the United States — and its 36.1 per cent slice of developed-world carbon dioxide — out of the picture and Australia also refusing ratification, other signatories are urged to move forward so that the policy can begin to take effect. The European Union and Japan quickly ratify, but Russia balks, telling a New Delhi meeting in October that the government needs more time to think it over. The delay stalls enforcement of the Protocol, and the New Delhi talks place a fresh focus on adapting to climate impacts that are increasingly seen as inevitable.
After the scorching summer of 2003, which broke temperature records across Europe and killed thousands, political will for emissions cuts warms up. The Russian government grudgingly ratifies the Kyoto protocol in November 2004, while seeking EU support for Russia's membership in the World Trade Organization. The Protocol can now come into force in February 2005. (See Russia backs Kyoto treaty)
Extreme summer weather — a devastating US hurricane season this time — again puts climate concerns on the front page. Surrounding the September deluge in New Orleans are May's climate conference of government experts in Bonn, July's G8 meeting at the Gleneagles hotel in Scotland, where development and climate change are high on the agenda. and December's meeting of parties to the Kyoto Protocol in Montreal.
Former World Bank chief economist Sir Nicholas Stern delivers a report on the economics of climate change to the UK government. Calling climate change the greatest and widest-ranging market failure ever seen, Stern sums up the likely costs of various policy options and prescribes how to minimize the social and economic impacts of future warming.
The IPCC and Al Gore share the year's Nobel Peace Prize for "their efforts to build up and disseminate knowledge about man-made climate change." The prize follows an Oscar for Gore's 2006 climate documentary An Inconvenient Truth and adds further gravitas to the Panel's latest and most daunting report (PDF).
Yielding at last to international pressure, the United States comes back to the table at a major UN conference on post-Kyoto climate policy held in Bali, Indonesia. Australia's newly elected government kicks off the meeting by ratifying Kyoto, leaving the US the only industrialized country to reject the Protocol.
In April, Bangkok hosts the next conference on the Bali roadmap. Though the meeting's goal is merely to set a timetable for future meetings, eleventh-hour struggles drain the delegates once again. 'Sectoral' approaches to emissions cuts, which would push selected industries to reduce their greenhouse gases, gain attention thanks to a campaign by Japan. But developing nations led by China — now the world's top emitter, having surpassed the United States in 2007 — continue to resist the commitments these approaches would impose. More tug-of-war looks likely at the upcoming UN meeting in Poznan, Poland, in December. (See Post-Bali paradox at UN meeting in Bangkok)
To complete Kyoto's successor on schedule, delegates must sort out a lengthening list of divisive issues, some of which have barely budged in years. And there's little sign yet of a surge of activity after the galvanizing IPCC report and Bali conference in 2007. But past UN climate negotiations reveal a long habit of last-minute solutions, and most players expect the upcoming election of a new US president to greatly alter the field.