Early this week, a meeting was organised by R Chidambaram, Principal Scientific Adviser (PSA) to the Prime Minister, to finalise a national plan for adapting to climate change. One of the things that the PSA proposed was buying or building a supercomputer to help India make more informed decisions.

As India sets out to draw its first roadmap to combat impacts of this change, large holes in India-specific data on impact of climate change is obvious. Current model simulations give one degree latitude and one degree longitude, which are too coarse for planning. This idea was proposed in the first meeting of the Prime Minister’s Council on Climate Change held this month.

According to experts, the supercomputer will be of 100 teraflops, costing approximately Rs 30-35 crore. This would be a huge technological leap from the 10 teraflops of the Param series already existing in India. Though modules can be added to it, the outcome can be skewed results, explained scientists. There are 25 such computers in the world.

“Climate change is a grand challenge. These challenges push the frontiers of the computing to a new level,” said N Balakrishnan of the Indian Institute of Science who is being consulted by the PSA on this. He is confident that India has the capacity to build its own supercomputer.

For now, the Intergovernmental Panel on Climate Change has some information on India-specific impacts: There would be increase in rainfall by 15-40 per cent by the end of the 21st century with high regional variability. The mean temperature would increase by three to six degrees by the end of the 21st century.

The policy makers want to know specifically how much water would be available in the Himalayan rivers in the next 50 years. Also, which areas of the country would be worst affected by extreme weather. Apart from helping decide its own policies to combat these effects, some of this information is vital for leveraging international funds for adaptation. Exact information would help build a case for India in international climate change negotiations--it would illustrate how some parts of the country are vulnerable.

“China is one country that is light years ahead of us in modelling capabilities,” said R K Pachauri, chairman, IPCC, making a case for ramping up India’s computing facilities. China has already come up with its domestic roadmap for adapting to climate change.

Experts agree that understanding and predicting earth’s climate system, particularly climate variation, presents one of the most difficult challenges in science. According to the council, a supercomputer could help shed light on this debate.