Late Triassic | climate and environment during the triassic period
During the beginning of the Triassic Era, the earth consisted of a giant landmass known as Pangea, which covered about a quarter of earth's surface. Towards the end of the era, continental drift occurred which separated Pangea. At this time, polar ice was not present because of the large differences between the equator and the poles.[
The Middle Triassic was known to have consistent intervals of high levels of humidity. The circulation and movement of these humidity patterns, geographically, are not known however. The major "Carnian Pluvial Event" stands as one focus point of many studies. Different hypotheses of the events occurrence include eruptions, monsoonal effects, and changes caused by plate tectonics. Continental deposits also support certain ideas relative to the Triassic period. Sediments that include red beds, which are sandstones and shales of color, may suggest seasonal precipitation. Rocks also included dinosaur tracks, mudcracks, and fossils of crustaceans and fish, which provide climate evidence, since animals and plants can only live during periods of which they can survive through.
The Late Triassic is described as semiarid. Semiarid is characterized by light rainfall, having up to 10-20 inches of precipitation a year. The period had a fluctuating, warm climate in which it was occasionally marked by instances of powerful heat. Different basins in certain areas of Europe provided evidence of the emergence of the “Middle Carnian Pluvial Event." For example, the Western Tethys and German Basin was defined by the theory of a middle Carnian wet climate phase. This event stands as the most distinctive climate change within the Triassic period. Propositions for its cause include:
Theories and concepts are supported universally, due to extensive areal proof of Carnian siliciclastic sediments. The physical positions as well as comparisons of that location to surrounding sediments and layers stood as basis for recording data. Multiple resourced and recurring patterns in results of evaluations allowed for the satisfactory clarification of facts and common conceptions on the Late Triassic. Conclusions summarized that the correlation of these sediments led to the modified version of the new map of Central Eastern Pangea, as well as that the sediment’s relation to the “Carnian Pluvial Event” is greater than expected.
The impacts that the Late Triassic era had on surround environments and organisms were wildfire destruction of habitats and prevention of photosynthesis. Climatic cooling also occurred due to the soot in the atmosphere. Studies also show that 103 families of marine invertebrates became extinct at the end of the Triassic, yet another 175 lived on into the jurassic. Marine and extant species were hit fairly hard by extinctions during this period. Almost 20% of 300 extant families became extinct, and Bivalves, Cephalopods, and Brachiopods suffered greatly. 92% of Bivalves were wiped out episodically throughout the Triassic.
The end of the Triassic also brought about the decline of corals and reef builders during what is called a “reef gap”. The changes in sea levels brought this decline upon corals, particularly the Calcisponges and Scleractinian corals. However, some corals would make a resurgence during the Jurassic period. 17 Brachiopod species were also wiped out by the end of the Triassic. Furthermore, Conulariids became entirely extinct.