Editing Permian–Triassic extinction event (section)

==Comparison to present global warming==
The PTME has been compared to the current [[anthropogenic global warming]] situation and [[Holocene extinction]] due to sharing the common characteristic of rapid rates of carbon dioxide release. Though the current rate of greenhouse gas emissions is more than an order of magnitude greater than the rate measured over the course of the PTME, the discharge of greenhouse gases during the PTME is poorly constrained geo-chronologically and was most likely pulsed and constrained to a few key, short intervals, rather than continuously occurring at a constant rate for the whole extinction interval; the rate of carbon release within these intervals was likely to have been similar in timing to modern anthropogenic emissions.<ref name="VolumeRateCO2" /> As they did during the PTME, oceans in the present day are experiencing drops in pH and in oxygen levels, prompting further comparisons between modern anthropogenic ecological conditions and the PTME.<ref>{{cite journal |last1=Payne |first1=Jonathan L. |last2=Clapham |first2=Matthew E. |date=May 2012 |title=End-Permian Mass Extinction in the Oceans: An Ancient Analog for the Twenty-First Century? |url=https://www.annualreviews.org/doi/abs/10.1146/annurev-earth-042711-105329 |journal=[[Annual Review of Earth and Planetary Sciences]] |volume=40 |issue=1 |pages=89–111 |doi=10.1146/annurev-earth-042711-105329 |bibcode=2012AREPS..40...89P |access-date=31 May 2023}}</ref> Another biocalcification event similar in its effects on modern marine ecosystems is predicted to occur if carbon dioxide levels continue to rise.<ref name="ElevatedAtmosphericCO2DelayedBioticRecovery" /> The changes in plant-insect interactions resulting from the PTME have also been invoked as possible indicators of the world's future ecology.<ref>{{Cite journal |last1=Cariglino |first1=Bárbara |last2=Moisan |first2=Philippe |last3=Lara |first3=María Belén |date=November 2021 |title=The fossil record of plant-insect interactions and associated entomofaunas in Permian and Triassic floras from southwestern Gondwana: A review and future prospects |url=https://linkinghub.elsevier.com/retrieve/pii/S0895981121003588 |journal=[[Journal of South American Earth Sciences]] |language=en |volume=111 |pages=103512 |doi=10.1016/j.jsames.2021.103512 |access-date=18 June 2024 |via=Elsevier Science Direct}}</ref> The similarities between the two extinction events have led to warnings from geologists about the urgent need for reducing carbon dioxide emissions if an event similar to the PTME is to be prevented from occurring.<ref name="VolumeRateCO2" />

Just as during the PTME, contemporary oceans experience their extreme change-change in the form of a decline in pH and oxygen levels, which further strengthens the pull between the two events. This is emphasised by [[geologist]] [[Lee Kump]]:<blockquote>"The Permian-Triassic mass extinction provides a stark reminder of the consequences of rapid carbon dioxide emissions. During the PTME, volcanic activity unleashed massive amounts of CO₂, leading to ocean acidification, deoxygenation, and widespread ecological collapse. Today, we see human activities driving similar processes at an even faster rate. The geological record shows that once these tipping points are reached, the cascading effects on ecosystems can last for millions of years."<ref>{{Cite web |title=Greatest mass extinction driven by acidic oceans, study finds |url=https://www.sciencedaily.com/releases/2015/04/150409143033.htm |access-date=2024-11-24 |website=ScienceDaily |language=en}}</ref><ref>{{Cite news|url=https://www.nytimes.com/2017/07/29/opinion/sunday/when-life-on-earth-was-nearly-extinguished.html|title=Opinion &#124; When Life on Earth Was Nearly Extinguished|first=Peter|last=Brannen|work=The New York Times |date=July 29, 2017|via=NYTimes.com}}</ref> </blockquote>If it continues to rise, the consequence could be another bio-calcification crisis, as seems to have occurred in the fossil record, which would have disastrous consequences for modern marine ecosystems.{{cn|date=April 2025}}