Related by context. Frequent words. (Click for all words.) 73 atmospheric carbon dioxide 73 atmospheric CO2 70 greenhouse gas concentrations 67 atmospheric concentrations 65 greenhouse warming 59 carbon dioxide 58 nitrous oxide emissions 58 ozone depletion 57 greenhouse gases 56 carbon dioxide CO2 56 CO2 56 airborne pollutants 56 anthropogenic 56 Greenhouse gases 55 gigatons 55 albedo 55 troposphere 54 Carbon dioxide emissions 54 greenhouse gasses 54 heat trapping carbon dioxide 53 mid latitudes 53 extinctions 53 radiocarbon 53 #ppm [001] 52 aerosols 52 ozone 52 Little Ice Age 52 atmospheric 51 Carbon Dioxide 51 greenhouse emissions 51 greenhouse gas emissions 51 glaciation 51 methane 51 abundances 51 pollutants 51 Carbon dioxide 51 carbon dioxide emissions 51 water vapor 51 streamflow 50 mass extinctions 50 acidification 50 GHGs 50 degrees Fahrenheit 50 Concentrations 50 greenhouse gases emitted 50 salinity 50 particulate emissions 50 volcanism 50 degree centigrade 50 emissions 50 carbon dioxide methane 50 permafrost 50 glaciers 49 temperate regions 49 heat trapping gases 49 insect populations 49 radioactive decay 49 alkalinity 49 global warming 49 mountain glaciers 49 atmospheric circulation 49 ppm 49 absorb carbon dioxide 49 atmospheric chemistry 49 heat trapping greenhouse gases 49 polar regions 49 temperatures 49 pollutant 49 decadal 48 ozone depleting substances 48 GHG emissions 48 Tibetan Plateau 48 Greenland ice 48 Co2 48 sulfur dioxide emissions 48 concentrations 48 sediments 48 latitudes 48 heat trapping emissions 47 fungal spores 47 protective ozone layer 47 burning fossil fuels 47 C# emissions 47 particulate pollution 47 carbon sinks 47 CO2 emissions 47 carbon dioxide CO2 emissions 47 ozone pollution 47 cosmic rays 47 acid rain 47 Antarctic ice 47 Serreze 47 phytoplankton 47 biosphere 47 #.#C [002] 47 mercury pollution 47 sulfate 47 air pollution 47 methyl mercury 47 warming gases 47 Sulfur dioxide