The 130-nation body, which concluded its 6-day deliberation on Saturday at Valencia in Spain came out with a synthesis of its 4th assessment report on climate change. The warming of the climate system is unequivocal, as is now evident from the observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising average sea level, the synthesis report said.
In a web telecast of the press conference on Saturday, The UN secretary-general, Ban Ki-moon urged the national governments to do more to arrest the climate change. The report also offered blueprints to avert the worst catastrophes, he said and added that climate change imperils the most precious treasures of our planet.
Ki-moon said that the report would be placed before the forthcoming UN framework on climate change meeting in Bali in Indonesia to review the progress made under the Kyoto Protocol.
The report noted that observational evidence from all continents and most oceans showed that many natural systems were being affected by regional climate changes, particularly rise in temperatures. Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of the human activities since 1750 and now far exceed pre-industrial value determined from ice cores spanning many thousands of years.
Most of the observed increase in globally-averaged temperatures since the mid-2oth century is very likely due to the observed increase in anthropogenic GHG concentrations. It is likely there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antarctica), it said.
The IPCC further said that there was high agreement and much evidence that with current climate change mitigation policies and related sustainable development practices, global GHG emissions would continue to grow over the next few decades. Continued GHG emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century.
The IPCC expressed its confidence over its third assessment report and said that the projected patterns of warming and other regional-scale features, including changes in wind patterns, precipitation and some aspects of extremes and sea ice changes. The third assessment has enabled more systematic understanding of the timing and magnitude of the climate change impact, it said.
However, the synthesis report expressed some amount of optimism. It said both bottom-up and top-down studies indicate that there is high agreement and much evidence of substantial economic potential for mitigation of global GHG emissions below current levels. While top-down and bottom-up studies are in line at the global level, there are considerable differences at the sectoral level.