The forecast just seems to get gloomier. Climate change may dramatically increase the risk of flooding across the globe, even far from shorelines, say scientists in the journal Nature. The reason: plants won't soak up as much moisture in a world with more greenhouse pollution. When plants are exposed to high levels of carbon dioxide, holes in their leaves, called stomata, react by getting smaller. The trouble is, smaller stomata also reduce the evaporation of water. Plants that retain more water don't need to soak up as much from the ground. Rain falling on water-saturated soil will run off into the rivers, causing floods. "There's a positive message to be taken from this, too," says co-author Richard Betts, a climate scientist at the U.K.'s Met Office Hadley Centre. The phenomenon could help regions that now suffer from drought.