1. Institute for Atmospheric and Climate Science; ETH Zurich; Zurich 8092 Switzerland
2. CREAF; Cerdanyola del Vallès Catalonia 08193 Spain
3. Earth and Environmental Sciences Area; Lawrence Berkeley National Lab; Berkeley CA 94709 USA
4. Department of Environmental Science, Policy and Management; UC Berkeley; Berkeley CA 94720 USA
5. AXA Chair of Biosphere and Climate Impacts; Department of Life Sciences; Imperial College London; Silwood Park Campus London SL5 7PY UK
6. CSIC; Global Ecology Unit CREAF-CSIC-UAB; Bellaterra, Catalonia 08193 Spain