London - Climate change is the most serious global threat we face. The Intergovernmental Panel on Climate Change, a group of more than a thousand leading climate scientists, has recently updated its predictions. The report makes grim reading: Over the next century we may see increased disease in Latin America, more acute water shortages in East Asia and the loss of up to 50 percent of the coastal wetlands of North America. These are just three examples from a summary of the IPCC's work that runs to 20 pages. Even if only some of the predictions come to pass, they will constitute an environmental catastrophe without parallel.