how was the climate during this period?
The global climate during the Paleogene departed from the hot and humid conditions of the late Mesozoic era and began a cooling and drying trend.
Paleogene
The global climate during the Paleogene departed from the hot and humid conditions of the late Mesozoic era and began a cooling and drying trend 
where was the material that was eroded by the colorado river deposited Regions in the Mesozoic and Cenozoic what is the second one? It is the current and most recent of the three geological eras of the Phanerozoic Eon. where is this era's name derive from? It means "new life," and is derived from Greek "kainós" "new," and "zōḗ" "life." what are its divisions? It is divided into three periods: the Paleogene, Neogene, and Quaternary; and seven epochs: the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene. what is the time period of the first division? It spans 43 million years from the end of the Cretaceous Period million years ago (Mya) to the beginning of the Neogene Period Mya.
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Paleogene [SEP] Climate and geography
The global climate during the Paleogene departed from the hot and humid conditions of the late Mesozoic era and began a cooling and drying trend which, despite having been periodically disrupted by warm periods such as the Paleocene–Eocene Thermal Maximum, persisted until the temperature began to rise again due to the end of the most recent glacial period of the current ice age. The trend was partly caused by the formation of the Antarctic Circumpolar Current, which significantly lowered oceanic water temperatures. A 2018 study estimated that during the early Palaeogene about 56-48 million years ago, annual air temperatures, over land and at mid-latitude, averaged about 23–29 °C (± 4.7 °C), which is 5–10 °C higher than most previous estimates.