Global Change and the Earth System: A Planet Under Pressure

abrupt changes agricultural anthropogenic approach areas atmosphere Biodiversity biogeochemical cycles biological biological pump biosphere carbon cycle century challenge changing Earth climate change climate system climate variability CO₂ coccolithophorids complex consequences critical thresholds DIVERSITAS Dobson units dynamics Earth System functioning Earth System science Earth's environment ecosystem environmental change programmes example feedbacks fertilisation forcings fossil fuel fossil fuel combustion gases GCTE global change research global environment global environmental change global scale global sustainability global system Greenland human activities human population human-driven changes humankind hydrological cycle IGBP SCIENCE IHDP impacts important increasing integrated Earth System interacting stresses International Project Office land-cover land-use change last half million natural variability nonlinearities occurred ocean ozone Past Global Changes patterns Paul Crutzen phytoplankton planet planetary machinery ppbv processes regional role sardine scientific sectoral simulation sink soil erosion Source species strategies sustainable future temperature terrestrial ecosystems trigger underlying drivers understanding Vostok ice core WCRP