Forests, which cover a third of the Earth's surface, are key to carbon storage and the water cycle, although the full extent of their impact has yet to be fully understood. In a new study  published in Nature Communications  researchers from Stockholm University and international colleagues are providing new insight into the complex role that forests play in the climate system and water cycle. The research, involving scientists from 11 institutions in five countries, including Sweden, the United Kingdom, Finland, Germany and Brazil, points to a complex relationship between forests, particularly their emissions of organic gases, and the formation of reflective clouds that could affect global temperatures. (Stockholm University, more at phys.org)