Related by context. Frequent words. (Click for all words.) 77 CO2 emissions 71 C# emissions 70 carbon dioxide emissions 70 carbon emissions 67 CO2 emission 66 CO2 emitted 66 carbon dioxide CO2 emissions 65 emissions 65 carbon dioxide emission 65 greenhouse gas emissions 65 carbon emission 64 greenhouse gas GHG emissions 64 carbon emitted 63 CO2 63 GHG emissions 62 greenhouse emissions 62 particulate emissions 61 reducing CO2 emissions 61 reduce carbon emissions 60 exhaust emissions 60 nitrous oxide emissions 60 NOx emissions 60 GHGs 59 emission 59 greenhouse gasses 59 Co2 58 reducing carbon emissions 58 pollutant emissions 58 carbon dioxide emitted 58 greenhouse gases 58 carbon footprint 57 Carbon dioxide emissions 56 GHG 56 greenhouse gases emitted 56 GHG reduction 56 Emissions 56 carbon dioxide CO2 56 greenhouse gas 55 greenhouse gas emission 54 megatonnes 54 nitrogen oxide emissions 54 NOx 53 carbon footprints 53 tailpipe emissions 53 emission reductions 53 greenhouse gas GHG 53 greenhouses gases 52 carbon dioxide 51 airborne pollutants 51 #g/km [001] 51 emission reduction 51 HCFC 50 atmospheric CO2 50 carbon 50 NO2 49 heat trapping carbon dioxide 49 consumption 49 Greenhouse Gas Emissions 49 heat trapping emissions 49 nitrogen oxides 49 nitrogen oxide 49 carbon emitting 48 carbon offsetting 48 g km 48 air pollution 48 gigatons 48 pollution 48 Carbon Footprint 47 consumptions 47 atmospheric carbon dioxide 47 ecological footprint 47 Carbon Dioxide 47 global warming gases 46 efficiency 46 HCFCs 46 CAFE standards 46 harmful gases 46 carbon neutral 46 Emission 46 sulfur dioxide emissions 46 diesel particulate filter 46 greenhouse gas concentrations 45 VOCs 45 particulate filter 45 particulate matter 45 SO2 45 particulate pollution 44 #ppm [001] 44 carbons 44 zero emission 44 Air Passenger Duty 44 #g/km [002] 44 Greenhouse gases 44 ozone depleting 44 ozone depleting substances 44 mercury emissions 44 fine particle pollution 44 HEVs 44 megatons 43 Greenhouse Gases 43 nitrogen dioxide