JUST HOW agriculture will fare on a heating planet has been an active area of research ever since the problem of global warming was first widely recognised in the 1980s. A new paper, published this week in Nature, paints an especially comprehensive picture. It is also a dispiriting one. In the first project to predict how farmers will adapt to climate change based on how they are doing so at present, the authors find that food production in the world’s existing breadbaskets, such as the American Midwest, will be among the hardest hit, although it may improve in currently less productive northerly regions such as Canada, China and Russia. And whereas adaptation will help offset some global losses, it will not be nearly enough to avoid them overall.