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What evidence shows that Alaska and the Arctic had subtropical conditions during the early Eocene?
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Tertiary Period
Gypsum cones, which resulted from the evaporation of the Mediterranean Sea during the Messinian Salinity Crisis, in the Sorbas basin, Spain.
Evidence for subtropical conditions in Alaska and the Arctic during the early Eocene Epoch is primarily derived from the fossil record of flora and fauna found at these high latitudes.1
Key findings include:
- Marine Life: Fossil remains of tropical faunas, such as mollusks and sharks, have been discovered in Alaska and on the island of Spitsbergen in the Norwegian Arctic.1
- Terrestrial Life: The presence of reptiles and mammals on Ellesmere Island in the Canadian Arctic Archipelago further supports the existence of these warm conditions.1
- Temperature Data: During the Paleocene-Eocene Thermal Maximum (PETM), sea surface temperatures in the high-latitude Arctic are estimated to have reached as high as 23 °C (73 °F), which is comparable to modern subtropical and warm-temperate seas.23
These paleontological records demonstrate that high-latitude regions experienced significantly warmer climates during the early Eocene than they do today.1