Related by context. Frequent words. (Click for all words.) 71 Little Ice Age 56 atmospheric CO2 55 Holocene 53 mass extinctions 52 atmospheric carbon dioxide 52 volcanism 51 Pleistocene 51 greenhouse gas concentrations 51 latitudes 49 anthropogenic 49 Neanderthals 49 polar regions 48 PETM 48 prehistory 48 glaciers 47 Eocene 47 climatological 47 northern latitudes 47 paleo 47 climatologists 47 albedo 46 troposphere 46 sunspots 46 Climategate 46 extinctions 45 radiocarbon dating 45 climatology 45 mass extinction 45 sunspot 45 plate tectonics 45 epochs 45 vernal equinox 45 Greenland ice 45 polar ice 45 Paleolithic 45 El Niño 44 Northern Hemisphere 44 climatic 44 tropics 44 Bronze Age 44 Cretaceous 44 ozone depletion 44 polar 44 boreal 44 Ice Age 44 #.#C [002] 44 Antarctica 44 geologic 43 Trenberth 43 Triassic 43 Homo sapiens 43 permafrost 43 glacial ice 43 global warming 43 equatorial 43 Neanderthal 42 Neolithic 42 Greenland 42 prehistoric 42 Middle Ages 42 warming 42 diatoms 42 World Meteorological Organization 42 IPCC 42 Mayan calendar 41 Industrial Revolution 41 hunter gatherers 41 martian 41 biosphere 41 ancients 41 epoch 41 mammoths 41 winter solstice 41 La Niña 41 millennia 41 volcanic activity 41 CRU 41 National Climatic Data 41 Droughts 41 Dark Ages 41 La Nina 41 droughts 41 Global Warming 41 Antarctic Peninsula 41 Arctic 41 #AD [002] 41 equator 40 Babylonians 40 antiquity 40 warmer 40 millenniums 40 volcanic eruptions 40 Iron Age 40 heatwaves 40 El Nino 40 Arctic tundra 40 fossil 40 Anasazi 40 Antarctic 40 wolverines 40 equinox