According to the most recent paleoclimatic reconstructions the beginning of the Paleogene (65.5 million years ago) was characterized by global cooling. The views of experts on the causes of the cooling vary but most of them, including the first American scholars, believe it was due to the collision of the Earth with an asteroid having a diameter of about 10 km (the epicenter of the conflict was in the Gulf of Mexico). The cooling off period was significant, but short-lived, and was caused by a sharp decline in Earth’s incoming solar radiation due to the atmosphere being shrouded in dust, ash and soot from fires.
Climate of the Paleocene (65.5 -58 million years ago)
After the initial cooling of the early Paleogene period there was a rapid and dramatic warming. According to various researchers,***, in the Paleocene epoch of the Paleogene period (66-58 million years ago), the entire Hyperborean area was within the Arctic warm temperate-subtropical climate and the southern boundary of this zone was along the southern tip of Greenland, northern Scandinavia, the Arctic coast of Russia, Chukotka, Alaska and Canada's Arctic coast.
Within the moderately warm-subtropical climate of the Arctic, the bulk of the Paleocene age coal basin of the Northern Hemisphere in West Greenland, Spitsbergen, in the lower Lena River in northern Siberia, Chukotka, Kamchatka, Alaska and in Arctic Canada was formed. These abundant deposits suggest a warm humid climate at the time and abundant growth, even in the polar regions, of lush vegetation. Based upon the evidence of fossil plant remains, the flora in the Arctic was subtropical with gingko trees, palms and cycads. Almost everywhere large plants grew which many researchers have linked to the polar light regime. (In the case of evergreen vegetation, this is probably better connected with the nearly-continuous ‘afternoon-style’ or low to the horizon sunlight).
About the same climate and vegetation was found on the southern extremity of South America, Australia, New Zealand, and on the coast of Antarctica.
Average temperatures in the Paleocene in the extreme northern and southern regions of the globe, according to various researchers, ranged from +10-15 °C to +15-20 °C and the temperature of the Arctic Ocean was not less than 15-18 °C. The climate at these high latitudes was characterized by extremely low temperature variation with latitude and small fluctuations of its seasonal and daily values.
At lower latitudes all continents enjoyed a humid tropical climate. In the Paleocene and Eocene the mean annual temperature in Europe was +27 °C, but by the end of the Eocene, it was down to + 20-22 °C.
The water temperature in the ocean was also significantly higher than today. Characteristically, the World Ocean was warm throughout the water column. Even the temperature at the bottom of the ocean was at least +10 °C. ***
In the Paleocene seas flourished many multi-celled organisms. They were so numerous that the accumulation of their shells formed thick layers of organic ocean-bottom sediment that became thick accumulations of limestone rock.
Climate of the Eocene (58-34 million years ago)
At the turn of the Paleocene and Eocene epochs of the Paleogene period, about 58 million years ago the climate was even warmer. This continued thru the Early Eocene until aboout 49 million years ago. According to some researchers, it was the warmest period on Earth over the past 500 million years.
The average annual temperature in the Early Eocene increased by 3-5 °C. This caused an even greater expansion of the tropical and subtropical zones and distribution of subtropical and tropical vegetation in the far north and south.
Most parts of the Earth at that time had a nearly uniform, warm and humid climate. Tropical forests were extended at least to the latitude of England and Newfoundland. Drilling of the bottom of the Arctic Ocean suggests they extended as far as the North Pole, where an average temperature of about +25 °C has been recorded and palm, avocado and other heat-loving plants grew. The water temperature in the Arctic was 22-23 °C.
The characteristic features of the early Eocene climate were an extremely small difference in seasonal and daily temperature with only slight changes due to changing latitude. The main vegetation of the time, growing even in the polar latitudes, were palms, cycads, tree ferns, mangroves and ginger combined with laurel, magnolia and aralia plants. In the Arctic and Antarctic regions turtles and crocodiles lived in their optimal temperature habitat between +20-25 °C.
During the Early Eocene epoch in the Northern Hemisphere, there was an arid zone where salts and variegated deposits were deposited in southern Kazakhstan, Kyrgyzstan, Mongolia, as well as in central and southern China. A similar zone with similar deposits was found in the Southern Hemisphere in southern Africa. However, there was not a real desert as we know it today. These arid zones more closely resembled today’s African savannah.
In the middle Eocene epoch (49-40 million years) there was a more clearly expressed separation of climate zones, associated with a gradual increase in temperature difference from the pole to the equator, and there was also some expansion of arid zones of both hemispheres and a corresponding reduction of humid, tropical climate zones. In the areas of warm, temperate and subtropical climate of the northern hemisphere (the southern boundary of which was found at Central Siberia and the Kamchatka Isthmus) grew oak, beech and chestnut forests. In some areas presumed to be at higher elevations grew pine, spruce, larch, birch, alder, rhododendron and other more temperate, cool-weather-loving plants. The climate became more extreme with hotter drier summers and cooler winters, which account for the increased precipitation. Approximately the same situation was observed in the southern hemisphere, in Tierra del Fuego and the Antarctic coast.
Despite this, the average annual temperature remained high (+10-15 °C in the north and from +5-10 °C in Antarctica).
The general trend of climate change was a displacement of the warm, temperate, subtropical and tropical climate zones from the poles towards the equator, increasing the seasonal extremes and diurnal temperatures with winter temperatures falling in the middle and high latitudes. This continued thru the Late Eocene epoch (40-34 million years ago). However, at this time the whole earth was still very warm and even in the Arctic grapes still grew.
Climate of the Oligocene (34-23 million years ago)
The most dramatic climate change took place in the late Eocene and Oligocene epochs, about 34 million years ago. At this time, there was a global catastrophe, as evidenced by Montanari (Montanari et al, 1993) in his paper on the iridium anomaly trap volcanism and formation of rift valleys and mountains at the border of the Eocene and Oligocene epochs. As a result of the Eocene-Oligocene disaster, Antarctica separated from South America and it apparently started glaciating.
The Eocene/Oligocene boundary (34 million years ago) shows a sharp cooling of climate, which was accompanied by a mass extinction of (mostly marine) organisms. It is sometimes associated with the collision of Earth with other cosmic bodies. This collision formed the Popigai crater (Siberia, Russia) and the Chesapeake Bay crater (USA).
Thus the Earth's climate became colder and drier. Ice formation occurred in the Arctic. Snow began to fall in the winter, not only in the higher, but also in the medium (50 °) latitudes. Because of reduced precipitation and continued ice formation, the global sea level began to fall, the run-off using pre-existing drainage systems of the West Siberian and other sea basins of the Northern Hemisphere.
Read more complete version of the work "The Paleocene-Eocene - the Golden Age of Humanity"
© AV Koltypin, 2010
© LA Fitzpatrick, 2013 (translation)
We, A. Koltypin the author of this work, and L.Fitzpatrick the translator of this work, give permission to use this for anypurpose except prohibited by applicable law, on condition that our authorship and hyperlink to the site http://earthbeforeflood.com is given
Read my works, announced in "Hyperborea - northern native land of mankind" and "Location of Continents and Oceans in the Paleogene" also my works "Fauna of the Paleogene", "The Position of Earth's Axis, the Earth's Rotation and the Length of Day in the Paleogene" and "Catastrophe at the Eocene-Oligocene boundary (34 million years ago)"