Climate change 679 climate change 365 Research & information: general 212 Environmental economics 149 Biology, life sciences 123 Ecosystems 111 China 109 Technology: general issues 98 Climate models 91 History of engineering and technology 80 Ecological science, the Biosphere 77 Forestry 77 Research and information: general 77 Sustainability 77 Environmental policy & protocols 75 Biodiversity 62 Economics 57 Environmental management 57 Vegetation 55 Land use 54 Applied ecology 51 Geography 50 human 50 article 48 spatiotemporal analysis 48 The environment 47 Indicator indicator 45 Sustainable development 44 Carbon 41 climate 40