What future for India's monsoons in a warmer world?

Posted: 28 September 2006

Climate change poses different problems in different parts of the world. In India one pressing concern is the impact of global warming on the precious monsoon rains, as Sunita Narain explains in these extracts from the latest editorial comment in the magazine Down to Earth.

Just imagine: floods in dry Rajasthan; drought in wet Assam. In both cases, devastation has been deadly, with people struggling to cope. But are these natural disasters or human-made disasters - signs of change of the world's climate systems? Or are these simply the result of mismanagement so that people already living on the edge of survival, cannot cope with any variations - small or big - in weather events?

In this multiple choice question, all answers are correct. In other words, this is a natural disaster, as monsoons in our region are highly variable, unpredictable and known to cause both floods and droughts. It is also a fact that these natural events are being exacerbated because we have forgotten how to live with nature.

So, we build cities without drainage; we build settlements in low-lying areas; we fill up our water bodies, which would store and recharge water for the dry season. We do everything which will make us more vulnerable when disaster strikes. But it is equally true that our climate is changing so that natural variations of weather events are becoming more extreme.

The problem is that the science of climate is not simple. But scientists are beginning to come out of the woodwork to tell us that the future is much more uncertain than we thought. The draft report of the Inter-governmental Panel on Climate Change confirms that climate change is a reality and predicts that global average temperatures this century will rise between 2°C and 4.5°C as a result of the doubling of carbon dioxide levels in the atmosphere...

India's lifeline

This 'warming' of the climate, scientists predicted, will lead to the melting of glaciers, rise in sea levels, changes in precipitation patterns worldwide and increased intensity of extreme weather events. But what they had not predicted was that all this could happen very fast...

What will global warming do to the lifeline - the true finance minister of South Asia, the monsoons? We know that the monsoons are perhaps the world's least understood natural phenomena. They are already variable and unpredictable. It also seems apparent that something is changing.

The monsoons are becoming more freakish - more cloudbursts like Mumbai's extraordinary rain in 2005 or Barmer's devastating showers in 2006 - seem to be happening. We also can sense that the rains are much more variable - some places drown while others thirst even as rainfall stays within normal average ranges. In other words, the variations are becoming more unnatural, with the intensity of rains increasing, but the number of rainy days decreasing.

I say all this with extreme caution. The simple fact also is that we do not know if any of this is happening in our part of the world. We do not know, because our met department refuses to entertain the possibility that things could be changing. Its refrain is that these freak weather events are in the range of normal variations. This, they tell you, is not the result of climatic change. In support, they pull out from the records instances when such events occurred. "Nothing unusual," they say. "Nothing to worry about," they mean.

But worry we must. This is not time for complacency and bad science.Something is happening to our lifeline. A recent paper, which modelled he impact of global climate change on the Indian summer monsoons, says that it is being destabilised.

On the one hand, aerosols - particles in the atmosphere because of fossil fuel and biomass burning - could well lead to cooling and reduced rain. On the other hand, global warming could lead to changes in the moisture and heat regimes which keep the monsoon circulatory patterns active. In other words, this could lead to increased variations in rainfall patterns, increased incidence of droughts and increased intensity of floods. But our scientists refuse to move with the times.

The fact of the matter is that if climate science is not simple, it is also not neutral. This science, when it establishes the effects of changes in global climate patterns, will also indict the world's richest countries for creating the problem that threatens the survival of millions. It is about victims and villains.

This is why this science, must belong to all - the rich and the poor. This is why our scientists must be engaged in this investigation. Their climate change denial game must stop. They must get out of their ostrich mentality so that they can tell us with more certainty if the signs we are reading are as ominous as they seem. They must tell us, so that not only can we be prepared but we can fight to substantially reduce pollution by the rich. Science must be the tool to drive the cleaner tomorrow.

Down to Earth is the magazine of the Delhi-based Centre for Science and Environment of which Sunita Narain is the director.