Climatic changes Environmental aspects 254 Government policy 216 Social aspects 164 Global warming 158 Economic aspects 126 Environmental policy 103 more ... Effect of human beings on 75 Research 75 Global environmental change 70 International cooperation 68 History 61 Environmental conditions 58 Greenhouse gas mitigation 55 Law and legislation 55 Political aspects 55 Sustainable development 50 Climatic factors 48 Climate change mitigation 47 Climatology 44 Human beings 44 Human ecology 42 Climate 38 Greenhouse gases 37 Nature 37 Energy policy 34 Water-supply 34 Forecasting 33 Risk assessment 33 Ecology 32 less ...