The assembly of the various large landmasses into the supercontinent of Pangea led to global warming and the development of dry to arid climates during Permian times. As low-latitude seaways closed, warm surface ocean currents were deflected into much higher latitudes (areas closer to the poles), and cool-water upwelling developed along the west coast of Pangea. Extensive mountain-building events occurred where landmasses collided, and the newly created high mountain ranges strongly influenced local and regional terrestrial climates.
Paleogeographic map of the continents during the Late Carboniferous and Early Permian epochs …
Encyclopædia Britannica, Inc.
The orogenies that marked the assembly of Pangea strongly influenced both climate and life. East-west atmospheric flow in the temperate and higher latitudes was disrupted by two high mountain chains—one in the tropics oriented east-west and one running north-south—that diverted warm marine air into higher latitudes. The continental collisions also closed various earlier marine seaways and isolated parts of the tropical shallow-water realms that were home to marine invertebrates. These realms eventually became endemic (regionally restricted) biological provinces.
Volcanism may have strongly influenced climate at the end of the Permian Period. Extensive Siberian flood basalts (the Siberian traps) in northeastern Siberia and adjacent western China erupted about 250 million years ago and for about 600,000 years extruded 2 million to 3 million cu km (480,000 to 720,000 cu mi) of basalt. The eruptions contributed great amounts of volcanic ash to the atmosphere, probably darkening the skies and lowering the efficiency of plants in taking up carbon dioxide from the atmosphere during photosynthesis. Some geoscientists contend that rising magma also burned through coal seams, releasing coal fly ash and adding large quantities of carbon dioxide to the atmosphere, both of which later mixed with and depleted oxygen from the oceans.
Paleogeographic map of the continents during the Late Carboniferous and Early Permian epochs …
Encyclopædia Britannica, Inc.
The orogenies that marked the assembly of Pangea strongly influenced both climate and life. East-west atmospheric flow in the temperate and higher latitudes was disrupted by two high mountain chains—one in the tropics oriented east-west and one running north-south—that diverted warm marine air into higher latitudes. The continental collisions also closed various earlier marine seaways and isolated parts of the tropical shallow-water realms that were home to marine invertebrates. These realms eventually became endemic (regionally restricted) biological provinces.
Volcanism may have strongly influenced climate at the end of the Permian Period. Extensive Siberian flood basalts (the Siberian traps) in northeastern Siberia and adjacent western China erupted about 250 million years ago and for about 600,000 years extruded 2 million to 3 million cu km (480,000 to 720,000 cu mi) of basalt. The eruptions contributed great amounts of volcanic ash to the atmosphere, probably darkening the skies and lowering the efficiency of plants in taking up carbon dioxide from the atmosphere during photosynthesis. Some geoscientists contend that rising magma also burned through coal seams, releasing coal fly ash and adding large quantities of carbon dioxide to the atmosphere, both of which later mixed with and depleted oxygen from the oceans.
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