Related by context. Frequent words. (Click for all words.) 62 methane hydrates 58 methane hydrate 57 Siberian permafrost 56 Arctic permafrost 55 gas hydrates 54 atmospheric methane 54 hydrothermal activity 53 deplete oxygen 53 methane 53 oceanic crust 53 polar caps 53 volcanic vents 52 aerosol particles 52 polar vortex 52 hydrological cycle 52 magmas 51 upwellings 51 glaciations 51 kerogen 51 icecaps 51 permafrost 51 biogenic 51 lithosphere 51 Lake Vostok 51 sulphates 50 phytoplankton blooms 50 plankton blooms 50 magma chamber 50 solar nebula 50 volcanism 50 Snowball Earth 50 thawing permafrost 50 interglacial period 49 glacial melting 49 mud volcanoes 49 carbonic acid 49 lavas 49 adsorb 48 ionised 48 icy crust 48 greenhouse warming 48 mesosphere 48 electrically conducting 48 diatoms 48 Younger Dryas 48 -# ° C [001] 48 silicates 48 melting permafrost 48 tropospheric 48 oxygen isotopes 48 polar icecaps 47 nucleation 47 polar regions 47 water vapor 47 geological formations 47 equatorial Pacific Ocean 47 Greenland Ice 47 isotope ratios 47 lunar soil 47 mid latitudes 47 marine sediments 47 geologically active 47 supercooled 47 temperature gradient 47 isotopic composition 47 desorption 47 explosive eruptions 47 crustal 47 glacial melt 47 solar corona 47 liquefies 47 iron oxides 47 spherules 47 atmospheric CO 47 protoplanetary disk 47 outgassing 46 Melting glaciers 46 WASP #b 46 atmospheric CO2 46 -# degrees Fahrenheit [002] 46 magmatic 46 Earthlike 46 underwater volcanoes 46 perturbations 46 incomplete combustion 46 volcanic gases 46 planetesimals 46 continental crust 46 zeolites 46 abiotic 46 volcanically active 46 glacial ice 46 methanogens 46 equatorial regions 46 Saturn moon Enceladus 46 carbon dioxide methane 45 carbon dioxide 45 Little Ice Age 45 hydrocarbon molecules 45 meltwater 45 moonlets