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The climate of the Triassic era was influenced by Pangaea, its centralized position stradling the equator, and the geologic activity associated with its breakup. Generally speaking, the continents were of high elevation compared to sea level, and the sea level did not change drastically during the period. Due to the low sea level, flooding of the continents to form shallow seas did not occur. Much of the inland area was isolated from the cooling and moist effects of the ocean. The result was a globally arid and dry climate, though regions near the coast most likely experienced seasonal monsoons. There were no polar ice caps, and the temperature gradient in the north-south direction is assumed to have been more gradual than present day. The sea level rose as the rift grew between North Africa and southern Europe, resulting in the flooding of Central and South Europe; the climates of terrestrial Europe were hot and dry, as in the Permian. Overall, it appears that the climate included both arid dune environments and moist river and lake habitats with gymnosperm forests.

rming on the Americas, North Africa was being split from Europe by the spreading rift. This division of the continents advanced further westward, eventually splitting eastern North America from North Africa.

The beginning of the Paleogene Period was very warm and moist compared to today’s climate. Much of the earth was tropical or sub-tropical. Palm trees grew as far north as Greenland!

By the end of the Paleogene, during the Oligocene Epoch, the climate began to cool.

The Quaternary Period is a geologic time period that encompasses the most recent 2.6 million years — including the present day. Part of the Cenozoic Era, the period is usually divided into two epochs — the Pleistocene Epoch, which lasted from approximately 2 million years ago to about 12,000 years ago, and the Holocene Epoch, which began about 12,000 years ago

During the Late Cretaceous, the high levels of atmospheric carbon dioxide heated up the Earth in the same way as they do today.

Table of Contents IntroductionThe Quaternary environmentGlaciationSea-level changesPaleoclimate

The most distinctive changes seen during the Quaternary were the advances of ice into temperate latitudes of the Northern Hemisphere.

The glacial landscapes were dominated by ice several kilometres thick that covered all but the highest peaks in the interior.

During the timeline of the era, several different events took place, eventually helping to shape the Earth as we know it today.

During the Proterozoic, the Earth had cooled considerably from the previous Hadean eon when the planet was covered by molten lava.

Near the end of the Proterozoic, ice sheets were growing towards the equator, and the entire planet was possibly engulfed under a thin layer of snow and ice.

The Triassic Period was the first period of the Mesozoic Era and occurred between 251 million and 199 million years ago

Climate was generally very dry over much of Pangaea with very hot summers and cold winters in the continental interior.

Some 250 million years ago, during the late Permian and early Triassic, the world was a greenhouse, much hotter than it is today.

About 65 million years ago the second greatest mass extinction in Earth history occurred, resulting in the loss of the dinosaurs as well as nearly 50% of all the world’s species. Though not nearly as severe as the end-Permian mass extinction, the end-Cretaceous extinction is the most famous mass extinction in Earth history

Terrestrial plants also suffered a major extinction at this time; in some regions up to 60% of latest Cretaceous plant species were absent in the subsequent Paleocene.

The causes of the end-Cretaceous extinction are still being debated by paleontologists. Researchers agree that a major factor was an asteroid about 10 kilometers in diameter that struck what is now the Yucatán peninsula in Mexico. The effects of the impact were catastrophic, probably including global forest fires, possibly a period of cold weather due to sunlight-blocking dust and smoke, and a subsequent period of hot climate caused by the high levels of CO2 released into the atmosphere by the impact.

Earth’s early atmosphere contained only small amounts of free oxygen

The oxygen-rich atmosphere that evolved later, and upon which oxygen-breathing life now depends, was a result of the origin of photosynthesis.

During the Precambrian, vast numbers of single-celled algae and cyanobacteria living in the seas eventually released enough oxygen to transform the environment.

India continued its slow-moving collision with Asia, which had already started the giant push-up of the Himalaya that continues today. Italy pushed into Europe, giving rise to the Alps. Spain butted France, and the Pyrenees rose.