By Sanjay Suri
LONDON, Feb 24 2003 (IPS)

In all this talk of climate change, we hear almost nothing about where the climate will change, and how, and when.

Difficult questions, but the Intergovernmental Panel for Climate Change (IPCC) will attempt to answer them as its fourth assessment review gets under way, the panel’s chairperson Dr Rajendra Pachauri told IPS in an interview.

Wait three years, and the IPCC – established in 1988 jointly by the World Meteorological Organization and the United Nations Environment Programme û will at least attempt to provide some answers.

“We will try to come up with the nature and extent of climate change for different regions of the world.” Some broad patterns are discernible already, says Dr Pachauri. “The increase in earth temperature is higher on average in the northern areas.”

The study over the next few years will mean for example a projection specific to South Asia “where sea rise levels look likely and changes in the pattern of glacier melting and the monsoons can have a very serious consequence for water availability and agriculture.”

The fourth report will look therefore at the link between climate change and sustainable development.

There are no certainties because what the climate throws at us will depend at least partly on what we throw into the air. On carbon dioxide, mostly. “Before industrialisation we saw 270 parts per million of carbon dioxide in the atmosphere. Now we are seeing close to 390 parts per million.”

That matters because carbon dioxide and other greenhouse gases (gases believed to contribute to global warming) form “a sort of blanket around the earth,” explains the IPCC chief. “The earth absorbs radiation, but the rest gets re-radiated. This gets blocked by the carbon dioxide blanket, and comes back to earth.” This traps heat around the earth.

Several of the developed countries agreed in Kyoto in Japan in 1997 in what came to be known as the Kyoto protocol to reduce emissions on average by around 5 per cent up to 2012.

“But this is only scratching the surface,” says Pachauri. “It can at most make only a very minor difference to the concentration of greenhouse gases.” The reduction so far has been on average no more than 3 per cent, and that too among countries who have ratified the treaty, he added.

The U.S. controversially withdrew from the Kyoto Protocol soon after President George Bush was elected two years ago. This seems to worry Dr Pachauri far less than it has many other environmentalists. The Kyoto Protocol is itself a marginal step, and no harm is done “if the U.S. stays out, and does more subsequently,” he says.

Make no mistake, climate patterns are changing. “We are not talking microclimate changes due to local factors,” Dr Pachauri says. For example high use of concrete in a big city will mean storage of heat, and there can be other such local factors. But there is no denying that the average mean temperature on earth rose 0.6 per cent in the last century., he says.

“There is enough evidence of glaciers melting, and bodies of snow and ice retreating, and of a measured rise in sea level,” he says. Climate patterns have always changed for natural reasons “but we have never before seen this rate of increase.”

The IPCC made a series of projections in its controversial third assessment review published in 2001 that the temperature of earth would rise by another 1.4 to 5.8 degrees Centigrade during the course of this century. “That is on the strength of present patterns without policy induced changes,” Dr Pachauri says. “If we take very strong steps, we will of course get different results.”

The IPCC projection in its third assessment has been challenged by some economists on the ground that it uses unreliable criteria in assuming economic growth. That gets linked to climate change because of perceived links that economic growth means greater industrialisation, which leads to greater emissions and which then affect the climate pattern.

Dr Pachauri says different measures for economic growth as expressed in a country’s gross domestic product (GDP) are significant for relative measures across different countries, “but this does not make a difference when looking at growth rates,” he says. “It is like measuring rise in temperature in centigrade or Fahrenheit, it makes no difference to the growth rate itself.”

But the fourth review will nevertheless adopt several new approaches, and “may come up with a revised set of figures,” Dr Pachauri says. The IPCC studies have been carried out so far by three groups, one looking at science, one at impact and adaptation issues, and the third at mitigation efforts. The fourth review will look more closely at “gaps and linkages” and work to “build in much greater consistency.”

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