The first Global Warming index is to be launched this week by UBS, allowing businesses most affected by the uncertainty of climate change - from ice-cream salesmen to makers of winter coats - to hedge their profits against it in a simple and transparent fashion.

Retail and institutional investors will also be able to buy exposure to, or short sell, the index in much the same way they would with the FTSE or Dow Jones stock indices. If temperatures rise, so will the value of the index.