A four letter word can make a world of difference. In 2001, the Intergovernmental Panel on Climate Change IPCC had observed that it was ‘likely’ that global warming was caused by human activity. On Friday, it added the word ‘very’ to its earlier prognosis. Decoded, the word signifies that there is an overwhelming possibility that global warming is indeed the result of human activity.

Now when 2,500 of the world’s finest climate scientists from 130 countries come to such a conclusion, it certainly makes the issue one of urgent international concern and puts pressure on every country — including India — to understand the new evidence. If global temperatures are likely to rise by up to 4.5 degrees Celsius by the end of this century, as is projected, it has implications for every country and inhabitant on the planet. China, which incidentally tried hard to push for less ‘alarmist’ language at the IPCC, has just got a reality check from home. Meteorological data has shown that the average national temperature in China this January was 1.4 degrees higher than normal and its northern regions are currently witnessing unprecedented drought. As indeed is the case in Australia, thousands of kilometres away.

It would be useful to read the IPCC findings along with the Nicholas Stern report of last October. Stern argues that responding with urgency to the global warming challenge makes not just environmental, but economic sense. Global warming, he has projected, could shrink the global economy by 20 per cent, but if action is taken promptly it would cost just 1 per cent of global gross domestic product. In other words, initiatives and investments in new technology, carbon offsets, renewable energy, fuel cells, hybrid cars, and forests — which act as natural carbon dioxide sinks — along with the deployment of financial instruments like carbon taxes and carbon trading, will be worth their weight in gold. Global warming has just become a global warning.