New research in the peer-reviewed journal PLOS Biology suggests plants in the north will remain limited by solar radiation — which is scarce at northern latitudes due to the shape of the Earth and its rotation, and is not likely to change as a result of climate — curbing any positive effects of warming and additional carbon dioxide. Furthermore, many plants in tropical regions will be unable to tolerate excessively high heat, especially if accompanied by drought. The result could be a loss in valuable growing days for populations who can least afford it and are ill equipped to cope with it.