Related by context. Frequent words. (Click for all words.) 63 Little Ice Age 63 glaciation 63 Pliocene 60 Medieval Warm Period 59 CO2 concentrations 57 atmospheric CO2 57 sunspot activity 55 atmospheric carbon dioxide 55 polar caps 54 mid latitudes 54 Holocene 54 atmospheric concentrations 53 volcanism 53 Greenland ice 52 greenhouse warming 52 sediment cores 51 Eocene 51 Serreze 51 decadal 51 Ordovician 51 Pleistocene 51 polar regions 50 radiocarbon 50 NSIDC 50 lake sediments 50 PETM 50 martian 50 mass extinctions 50 glacial ice 50 troposphere 50 El Ninos 50 permafrost 50 plate tectonics 50 greenhouse gas concentrations 49 atmospheric circulation 49 glacial melt 49 ENSO 49 albedo 49 Late Cretaceous 49 supernova explosion 49 glacial 49 abundances 49 X ray emission 49 anoxic 49 diatoms 48 northern latitudes 48 Antarctic Ice 48 glaciers 48 radioactive decay 48 sunspots 48 Antarctic ice 48 temperate regions 48 cosmic microwave background 47 gigatonnes 47 isotopic 47 geologic 47 volcanic activity 47 sunspot 47 Arctic Ocean 47 eruptive 47 Cretaceous 47 Martian 47 Triassic 47 equatorial regions 47 Martian surface 46 Antarctica 46 mountain glaciers 46 GRBs 46 ejecta 46 latitudes 46 polar 46 polar ice 46 epochs 46 gigatons 46 mass extinction 46 Precambrian 46 melting permafrost 46 magmatic 46 mammoths 46 streamflow 45 meltwater 45 supernova explosions 45 crustal 45 olivine 45 oscillations 45 gas hydrates 45 evapotranspiration 45 colder 45 Martian atmosphere 45 super Earths 45 nucleation 45 Ice Age 45 ice melts 44 paleo 44 #.#C [002] 44 species extinctions 44 Earth crust 44 supernovae 44 geomagnetic 44 cosmic ray 44 glacier