Related by context. Frequent words. (Click for all words.) 59 Medieval Warm Period 58 Little Ice Age 51 Holocene 50 aridity 49 glaciation 46 Climatic 46 fifteenth century 45 Pliocene 45 #AD [002] 45 millennia 45 prehistory 44 ENSO 44 Fertile Crescent 44 epochs 43 glacial melt 43 atmospheric CO2 43 millenniums 43 Archaic 43 Paleolithic 43 climatological 42 temperate regions 42 thirteenth century 42 Pleistocene 42 greenhouse warming 41 lake sediments 41 mass extinctions 41 Hellenistic 41 sunspot activity 41 Neolithic 41 landforms 41 Mesopotamian 41 plate tectonics 41 atmospheric circulation 41 CO2 concentrations 41 climatology 41 #BC [003] 41 volcanism 40 sediment cores 40 Tibetan Plateau 40 seventeenth century 40 synoptic 40 desiccation 40 antiquity 40 Neandertals 40 temperate zones 40 climatic 40 Middle Ages 40 #BC [002] 39 ancients 39 atmospheric 39 Industrial Revolution 39 glacial 39 anthropogenic 39 atmospheric chemistry 39 tropics 39 tectonics 39 paleo 39 Ancient Greeks 39 hunter gatherers 38 AD# [001] 38 decadal 38 polar caps 38 stalagmite 38 ancient 38 Permafrost 38 centuries 38 Roman Empire 38 eighteenth century 38 El Ninos 38 anthropogenic climate 38 climatologists 38 equatorial 38 Mesoamerica 38 species extinctions 38 Mediterranean basin 38 degree centigrade 38 Han Dynasty 38 Sumerians 38 Byzantine Empire 38 arctic 37 peat bogs 37 Babylonians 37 crustal 37 Eocene 37 twentieth century 37 mid latitudes 37 glaciologists 37 colonization 37 Mesoamerican 37 atmospheric carbon dioxide 37 millenia 37 oceanic 37 oscillation 36 latitudes 36 volcanic eruptions 36 #th century 36 ancient civilizations 36 nineteenth century 36 sixteenth century 36 Climatologists 36 polar