The Guardian reports: Europe has undergone a severe drought this summer, the worst in over a decade. Temperatures have been high across the continent, and have combined with low rainfalls. This drought, like the one in 2012 in the United States, are a sign of what our future holds in a warming world.

As humans emit greenhouse gases, the world warms. We already know that. But a warming world is also host to other changes. Among the most important changes are those to the water cycle. Scientists refer to this as the hydrological cycle – basically changes to the storage of water in the soil and underground, the evaporation of water into the atmosphere, and the subsequent rainfall and runoff that occurs.

A warmer atmosphere can hold more moisture, as people know through the personal experience of high humidity in warm months. Changes to humidity have been measured over the past decades and confirm our expectations. These changes lead to increased rainfall.

At the same time, higher temperatures accelerate evaporation, which dries out the soil and plants and can create drought conditions. [Continue reading…]