Editing Triassic–Jurassic extinction event (section)

=== Gradual climate change ===
The extinctions at the end of the Triassic were initially attributed to gradually changing environments. Within his 1958 study recognizing biological turnover between the Triassic and Jurassic, [[Edwin H. Colbert]]'s proposal was that this extinction was a result of geological processes decreasing the diversity of land biomes. He considered the Triassic period to be an era of the world experiencing a variety of environments, from towering highlands to arid deserts to tropical marshes. In contrast, the Jurassic period was much more uniform both in climate and elevation due to excursions by shallow seas.<ref name=":3" />

Later studies noted a clear trend towards increased aridification towards the end of the Triassic. Although high-latitude areas like Greenland and Australia actually became wetter, most of the world experienced more drastic changes in climate as indicated by geological evidence. This evidence includes an increase in [[carbonate]] and [[evaporite]] deposits (which are most abundant in dry climates) and a decrease in coal deposits (which primarily form in humid environments such as [[coal forest]]s).<ref name="TannerLucas" /> In addition, the climate may have become much more seasonal, with long droughts interrupted by severe [[monsoon]]s.<ref name=":7">{{Cite journal |last=T Parrish |first=Judith |date=1993 |title=Climate of the Supercontinent Pangea |url=https://www.ldeo.columbia.edu/~polsen/cpcp/parrish_93_sm.pdf |journal=[[The Journal of Geology]] |volume=101 |issue=2 |pages=215–233 |bibcode=1993JG....101..215P |doi=10.1086/648217 |jstor=30081148 |s2cid=128757269}}</ref> The world gradually got warmer over this time as well; from the late Norian to the Rhaetian, mean annual temperatures rose by 7 to 9&nbsp;°C.<ref>{{cite journal |last1=Cleveland |first1=David M. |last2=Nordt |first2=Lee C. |last3=Dworkin |first3=Steven I. |last4=Atchley |first4=Stacy C. |date=1 November 2008 |title=Pedogenic carbonate isotopes as evidence for extreme climatic events preceding the Triassic-Jurassic boundary: Implications for the biotic crisis? |url=https://pubs.geoscienceworld.org/gsa/gsabulletin/article-abstract/120/11-12/1408/2241/Pedogenic-carbonate-isotopes-as-evidence-for |journal=[[Geological Society of America Bulletin]] |volume=120 |issue=11–12 |pages=1408–1415 |bibcode=2008GSAB..120.1408C |doi=10.1130/B26332.1 |access-date=22 May 2023}}</ref> The site of Hochalm in Austria preserves evidence of carbon cycle perturbations during the Rhaetian preceding the Triassic-Jurassic boundary, potentially having a role in the ecological crisis.<ref>{{Cite journal |last1=Rizzi |first1=Małgorzata |last2=Thibault |first2=Nicolas |last3=Ullmann |first3=Clemens V. |last4=Ruhl |first4=Micha |last5=Olsen |first5=Troels K. |last6=Moreau |first6=Julien |last7=Clémence |first7=Marie-Emilie |last8=Mette |first8=Wolfgang |last9=Korte |first9=Christoph |date=1 August 2020 |title=Sedimentology and carbon isotope stratigraphy of the Rhaetian Hochalm section (Late Triassic, Austria) |url=https://www.sciencedirect.com/science/article/pii/S0921818120301016 |journal=[[Global and Planetary Change]] |volume=191 |pages=103210 |bibcode=2020GPC...19103210R |doi=10.1016/j.gloplacha.2020.103210 |issn=0921-8181 |s2cid=218917014 |access-date=26 November 2023 |hdl-access=free |hdl=10871/121120}}</ref>