Related by context. Frequent words. (Click for all words.) 87 greenhouse gases 83 greenhouse gas emissions 80 emissions 79 carbon dioxide emissions 79 carbon emissions 78 GHG 76 carbon dioxide 76 greenhouse emissions 75 GHG emissions 75 carbon emission 74 CO2 72 emission reduction 71 emission 71 CO2 emissions 69 emission reductions 68 heat trapping gases 67 Emissions 67 carbon 65 reduce carbon emissions 64 reducing carbon emissions 61 pollution 60 mercury emissions 60 pollutant 60 air pollution 59 global warming 59 polluters 59 climate change 58 nitrogen oxides 58 polluter 57 pollutants 57 sulfur dioxide 56 methane 56 emitters 55 fossil fuel 55 Kyoto Protocol 54 fossil fuels 53 reducing greenhouse gas 52 reduce greenhouse gas 52 carbon footprint 52 ozone 51 renewable energy 51 carbon offsets 51 burning fossil fuels 51 carbon sequestration 50 Clean Air 50 particulate matter 50 coal fired 50 EPA 50 acid rain 50 carbon capture 50 Kyoto 50 carbon footprints 50 gases 50 Kyoto protocol 50 Climate Change 50 renewables 50 smog 49 biofuel 49 carbon credits 49 Methane 48 biofuels 48 Climate 47 polluting 47 Climate Action 47 nitrogen 46 renewable fuels 46 biomass 46 Environmental Protection Agency 46 environmental 45 soot 45 deforestation 45 cleaner burning 45 coal 45 ethanol 45 carbon neutral 44 renewable 44 emitter 44 Pollution 44 particulates 44 climate 44 zero emission 44 volatile organic compounds 43 Carbon 43 Global Warming 43 alternative fuels 43 Renewable energy 43 water vapor 42 Global warming 42 tar sands 41 hydrogen 41 biodiesel 41 energy 41 Climate Change IPCC 41 mercury 41 greenhouse 41 toxic chemicals 41 ozone layer 41 environmentalists 40 emit 40 emitting 40 ETS