The head of the Intergovernmental Panel on Climate Change says countries need to adopt new strategies to cope with the extreme climate conditions that the world has been experiencing in recent years.
The Intergovernmental Panel on Climate Change says the 1990s have been the hottest decade in the past 1,000 years.
The chairman of the international panel, R.K. Pachauri, warns that as temperatures continue to rise, the frequency and intensity of extreme weather conditions such as heat waves and droughts might increase.
"When you fiddle around with the earth's weather system, the climate system, you are affecting the precipitation levels, you are affecting the movement of the oceans, because all of these are very delicately balanced, and they change if at all over hundreds and thousands of years, fractionally," said Mr. Pachauri, who met reporters on a recent visit to New Delhi. "But what we have done in a short period of time is having brought about a massive change in relative terms."
Mr. Pachauri said scientists are examining evidence to see if global warming has triggered events such as the recent heat wave in Europe, and the unusually hot summer in several other parts of the world.
Many climate researchers attribute global warming to human activity, mainly emissions of carbon dioxide and other greenhouse gases.
He said the effects of the earth's warming will stay for many decades even if countries reduce such emissions. This is because carbon dioxide lingers in the atmosphere for a long time.
For this reason, Mr. Pachauri said, nations, both rich and poor, must prepare for extreme climate conditions such as heat waves, floods, droughts, and submerging coastlines.
For example, said Mr. Pachauri, in coming decades climate change will endanger agricultural production in Asia, where large populations depend on farming. Bangladesh could lose seven percent of its land area as sea levels rise.
"We would probably have to direct our research effort coming up with crops that are drought-resistant, heat-resistant, and in some cases, you might have to actually change cropping patterns," said Mr. Pachauri. "In some cases you might actually need civil engineering structures to protect coastal areas and coastal installations. So there is a whole range of adaptation measures that will have to be taken into account."
He says developing countries may struggle the most with climate change, because they may lack the technology and the resources to adapt to it.