To the Institute of Defence and Strategic Analysis (IDSA) in New Delhi over the weekend for a fascinating panel discussion with some of India's climate change A team, including Environment Minister Jairam Ramesh and Prime Minister's Special Envoy Shyam Saran for the government, Nitin Desai, Ligia Norona and Arvind Gupta from influential think-tanks The Energy Resource Institute (TERI) and IDSA.

The occasion was the launch of a working group report on the security implications of climate change for India. This is a subject of increasing concern for Western security thinkers too. The concern is not that climate change will lead to war in itself, but that it will act as a "threat multiplier", increasing the risk of conflict and reducing human security. It's not difficult to envision how this might play out in South Asia. Take the obvious example of water: it's an increasingly scarce resource for India and its neighbours, so security analysts often focus on the implications of the melting of Himalayan glaciers, described as the world's "Third Pole".

The melting of Himalayan glaciers due to climate change would seriously affect the water supplies of 500 million (50 crore) people in the Himalaya-Hindu Kush region. The availability of freshwater in India is expected to drop from around 1,820 m3 per person today to below 1,000 m3 by 2025 as a result of the combined effects of population growth and climate change. Within India the inter-State politics of water already exist - for example between Karnataka and Tamil Nadu. And there are occasional rumbles from China, Pakistan and Nepal about the water resources they share with India. Tensions arising from water scarcity internally and internationally will increase, unless steps are taken to prevent this.

But the tone of the discussion by panel members at the IDSA discussion was encouraging. Although the threats to India's security were recognised (from sea level rise to increasing spread of disease), panel members saw that it was important not to "securitise" the climate debate. Jairam Ramesh, fresh from discussions with Pakistan's lead climate negotiator, held out the possibility that tackling the shared challenge of climate change might even help to improve Indo-Pak relations. And panel members recognised that lack of development and inequitable distribution of resources were themselves root causes of instability.

Despite the title of the session, the negotiations were never too far from panel members' thoughts - fitting enough as the day marked 100 days to go until Copenhagen. There were some encouraging noises of the need for collaborative discussion rather than competitive negotiation: if we take the former route we have a chance of achieving something greater than the sum of our parts. If we choose the latter, we will end up with a lowest common denominator result or no result at all - just look at the world trade talks in recent years. (I'll come back to the topical issue of trade and climate change again soon).

When we perceive a threat, we can choose whether to neutralise it through conflict or through other means. Climate change will present the region and the world with multiple threats. We can attempt to tackle these one by one as they arise or treat the issue as one of competition, of narrowly defined national interest, of "us" vs "them". Or we can recognise that this is the greatest challenge we face collectively - and work together to overcome it.