The report was released in Geneva at the World Climate Conference-3, hosted by the World Meteorological Organization. Some 2,000 delegates are meeting to lay the groundwork for a global system of climate change forecasting.
Arctic air temperatures have risen by almost twice the global average over the past several decades, according to the peer-reviewed scientific report, which warns that further warming could release more greenhouse gases now trapped in the Arctic's frozen soil.
"What this report says is that a warming Arctic is much more than a local problem, it's a global problem," said Martin Sommerkorn, senior climate change advisor with the WWF's Arctic Programme. "Simply put, if we do not keep the Arctic cold enough, people across the world will suffer the effects."
"Arctic soils and wetlands contain twice the amount of carbon currently in the atmosphere. As the Arctic warms, carbon that has been frozen and locked in for thousands of years starts to be given off as methane and carbon dioxide, adding to the greenhouse gas burden in the atmosphere, and further increasing climate change," according to the report.
Texas Joe Constantine follows polar explorer Eric Philips across partially melted sea-ice in Kane Basin in north Greenland. They are part of a team of scientists are on board the Greenpeace ship Arctic Sunrise documenting Arctic climate change. July 25, 2009 (Photo courtesy Greenpeace)
The combination of thawing Arctic sea ice and melting ice sheets in Greenland and West Antarctica is likely to raise global sea levels by about 1.2 meters (four feet) by 2100, more than previously thought, the report warns.
"The associated flooding of coastal regions will affect more than a quarter of the world's population," the WWF said.
Faster action to curb climate change may be possible if nations combine substantial cuts of carbon dioxide emissions with accelerated moves to control other greenhouse gases and pollutants, said scientists in Geneva for the climate forecasting conference.
Scientists estimate that nearly 50 percent of the emissions causing global warming in the 21st century are from non-CO2 pollutants, ranging from black carbon and low-level ozone to methane and nitrogen compounds.
Black carbon is emitted by the burning of forests, savannas and crop residues, by the inefficient burning of biomass and dung for cooking and by diesel engines and coal-fired power stations.
These so-called "climate forcers" will add to the warming caused by carbon dioxide from the burning of fossil fuels that have been building up since the Industrial Revolution unless their emissions are also addressed, say the climate scientists.
Achim Steiner, executive director of the UN Environment Programme, UNEP, said the time has come for further urgent scientific assessments to determine the precise contribution, impacts and the options for action on "non-CO2" pollutants.
"There remains some scientific uncertainty about some of these pollutants' precise contribution to global warming, but a growing body of science points to a potentially significant role," he said.
"The international community's over-arching concern must be to Seal a convincing Deal at the UN climate convention meeting in Copenhagen in less than 100 days time - one that puts the world on track towards swift and significant cuts in carbon dioxide while also providing the funding to assist vulnerable countries and communities to adapt," said Steiner.
Drew Shindell, a climatologist with the NASA Goddard Institute for Space Studies, and a lecturer in the Department of Earth and Environmental Sciences at Columbia University, said, "By including black carbon and tropospheric ozone precursors in climate mitigation strategies, alongside the longer-lived greenhouse gases, development strategies that are both more effective and less costly can be developed."
Shindell has been a reviewer of the assessments of the Intergovernmental Panel on Climate Change and whose science has been used extensively by the IPCC.
"The UN Environment Programme should be congratulated for raising these issues and calling for action. The science supporting the strong role of these pollutants in climate change and in damage to human and ecosystem health is becoming increasingly strong," said Shindell.
From Left, Michel Jarraud, head of the World Meteorological Organization and Rajendra Pachauri, chair of the Intergovernmental Panel on Climate Change in Geneva, Sept. 4, 2009 (Photo courtesy ENB)
In addition to their climate contribution, the scientists there are compelling economic and environmental reasons why some of the non-CO2 pollutants must be addressed under treaties such as the UN Framework Convention on Climate Change and its Kyoto Protocol, the Montreal Protocol on Substances that Deplete the Ozone Layer, and regional health agreements, national air quality strategies and voluntary initiatives.
Black carbon is among a suite of air pollutants linked to 1.6 million to 1.8 million premature deaths annually as a result of indoor exposure and 800,000 as a result of outdoor exposure.
Black carbon's likely near-term climate change contribution ranges from 20 plus percent to up to 50 percent of the CO2 warming effects, according to various researchers. Especially damaging are the black carbon emissions that end up on snow and ice, including the Arctic and Himalayan Tibetan Plateau.
Tropospheric ozone including near-surface ozone is a major greenhouse gas, harms human health and is linked to significant damage to crops and ecosystems.
A regional assessment report by the UNEP Atmospheric Brown Cloud project cited annual losses from the wheat, rice, corn and soya bean crop in China, Japan and the Republic of Korea alone - linked with ground level ozone - may be $5 billion a year.
Another study by the Massachusetts Institute of Technology estimates that five percent of cereal production in the United States is lost to ground level ozone and that by 2100 crop yields globally could be cut by 40 percent.
Up to a fifth of all summer-time hospital visits in the northeastern United States related to respiratory problems are linked to low-level ozone, sometimes referred to as smog.
Researchers at the University of Illinois are suggesting that tree growth in the United States is some seven percent less and that this will climb to up to 17 percent less by 2100 as a result of low-level ozone pollution.
Tropospheric ozone, which occurs from the ground up to 15 kilometers in altitude, is generated by substances such as carbon monoxide and nitrogen oxides mixing with emissions of petroleum products like volatile organic compounds and solvents in the presence of sunlight.
Researchers estimate that the contribution of tropospheric ozone to the greenhouse effect could range from 15 to 20 percent of the CO2 warming.
Meanwhile, nitrogen compounds, emitted from sources including animal wastes, sewage, inefficient use of fertilizers, sewage and vehicle emissions, are being linked to a wide range of impacts and not just climate change.
The rising number of dead zones, deoxygenated areas of seas and oceans, is raising concern over already vulnerable and depleted fish stocks. Meanwhile, nitrogen compound emissions are also contributing to changes in vegetation and ecosystems as a result of their artificial fertilizing effect.
Steiner said, "While carbon dioxide can remain in the atmosphere for centuries, some of these other pollutants such as black carbon and ozone have relatively short-lives in terms of days, weeks, months or years. Fast action across a broad front could thus deliver some quick wins on health, food security and wider environmental concerns while also making important contributions to advancing the climate change challenge and the achievement of the poverty-related Millennium Development Goals."
Copyright Environment News Service, ENS, 2009. All rights reserved.