Related by context. Frequent words. (Click for all words.) 68 glaciation 62 volcanism 60 Cretaceous Period 59 crustal 58 Quaternary 57 plate tectonics 56 Ordovician 56 Little Ice Age 56 Late Cretaceous 55 mid latitudes 55 lake sediments 55 mass extinctions 55 glacial 55 atmospheric circulation 54 Greenland Ice 54 Precambrian 54 Antarctic ice 54 sediment cores 54 subduction 54 Cretaceous 53 Geochemistry 53 Eocene 53 Tibetan Plateau 53 equatorial regions 53 Holocene 53 glacial melt 52 Pliocene 52 geologically active 52 sediments 52 El Ninos 52 Medieval Warm Period 52 icecap 52 geologic 52 atmospheric carbon dioxide 52 Greenland ice 52 equatorial 52 Pleistocene 52 glacial ice 52 sedimentary rock 52 sunspot activity 51 volcanic eruptions 51 Antarctica 51 Earth crust 51 ENSO 51 diatoms 51 Antarctic Ice 51 Wilkins Ice Shelf 51 greenhouse warming 51 Antarctic Peninsula 51 magmatic 51 permafrost 50 glaciers 50 volcanic activity 50 atmospheric CO2 50 mountain glaciers 50 polar caps 50 subduction zones 50 journal Geology 50 anomalously 49 melting permafrost 49 isotopic 49 Iapetus 49 sedimentary rocks 49 landforms 49 tectonic 49 mass extinction 49 species extinctions 49 equatorial Pacific 49 megafauna 49 basalts 49 oceanic 49 nitrogen fixation 49 Mesozoic 49 Oligocene 49 NSIDC 49 glaciologists 49 stalagmite 49 radiocarbon 49 meltwater 48 epochs 48 dinosaurs roamed 48 gas hydrates 48 upwelling 48 nucleation 48 CO2 concentrations 48 tectonics 48 subduction zone 48 temperate regions 48 polar regions 48 continental drift 48 Qinghai Tibet Plateau 48 atmospheric concentrations 48 polar ice 48 polar 47 deformation 47 lava flows 47 Earth magnetosphere 47 Ellesmere Island 47 fossils 47 Paleozoic 47 Greenland glaciers