Related by context. Frequent words. (Click for all words.) 53 CFCs 52 chlorofluorocarbons CFCs 50 stratospheric ozone 49 ozone depletion 48 ozone depleting chemicals 47 sulfur hexafluoride 47 hydrofluorocarbons 46 stratospheric ozone layer 45 aerosols 45 chlorofluorocarbons 45 ozone depleting 45 greenhouse gases GHGs 44 ozone layer 44 Antarctic ozone 44 Ocean acidification 44 sulphates 43 ultraviolet UV radiation 43 suspected carcinogen 43 ozone depleting substances 43 Aerosols 43 isoprene 43 aerosol particles 43 refrigerants 42 PCBs polychlorinated biphenyls 42 carbon tetrachloride 42 dental amalgam 42 Ozone Layer 42 Greenhouse gases 42 endocrine disruptor 42 harmful gases 42 biogenic 41 HCFCs 41 ionised 41 sulfur oxide 41 Refrigerant 41 Acrylamide 41 Toxic chemicals 41 sun ultraviolet rays 41 carbon dioxide methane nitrous 41 Sulfur dioxide 41 phosphine 40 engineered nanomaterials 40 nitrous oxides 40 incomplete combustion 40 ultra violet rays 40 harmful ultraviolet rays 40 contaminating groundwater 40 sulfur dioxide SO2 40 protective ozone layer 40 Hydrogen sulfide 40 dieldrin 40 HCFC 40 greenhouse gases GHG 40 Ultraviolet light 39 ultraviolet UV light 39 pollutants emitted 39 Carbon Dioxide 39 Greenhouse Gases 39 dioxide 39 gases emitted 39 hydrological cycle 39 potentially carcinogenic 39 chemtrails 39 carcinogenic substances 39 chlorinated solvents 39 toxicants 39 methane hydrates 39 Arctic permafrost 39 Montreal Protocol 39 HFCs 38 Persistent Organic Pollutants 38 compact fluorescent lamps CFLs 38 ionisation 38 vaporised 38 Carbon dioxide emissions 38 volcanic plume 38 SF6 38 NF3 38 potent neurotoxin 38 greenhouse warming 38 Carbon dioxide 38 endocrine disruption 38 absorbers 38 particulates 38 Cosmic rays 38 polycyclic aromatic hydrocarbons 37 cryosphere 37 atmospheric chemistry 37 outgassing 37 volcanic eruptions 37 liquid droplets 37 carbon sinks 37 RoHS Restriction 37 soot particles 37 acidification 37 insect borne diseases 37 biogeochemical 37 flame retardant chemicals 37 terrestrial ecosystems 37 petroleum distillates 37 acid rain