Due to human generated carbon dioxide emission, surface water is now more acidic compared to before the industrial revolution and this has led to the death of many lifeforms in the ocean. As at 2022, 62% of aquatic animals harvested were from the ocean and this is not sustainable for humans and are bad signs that a lot of things are going wrong with our climate but that's not all as the average sea level has risen up to 8–9 inches (21–24 centimeters) and In 2023, global average sea level reached a new level of 101.4 mm (3.99 inches) which was above the 1993 levels.
Just as we are altering the ocean so are we doing the same with land with land creation increase since the industrial revolution. In Nigeria, states like Lagos create more lands by sand filling and around the world new roads are created as major infrastructure and this is affecting the climate. Looking into agriculture, we have cultivated majority of the lands we have for agri purposes destroying forests that play an important in saving a lot of species.
Talking about food, it isn't like we have so much to eat as majority of our food comes from rice, corn, and wheat. Not forgetting that over 500 animals that were breed for agriculture and food purposes throughout history are extinct and about 17% of the livestock breeds we have face extinction.
We cannot talk about human effects on a possible Paleocene Eocene Thermal Maximum (PETM) event 2.0 and not mention the waste that we pour into oceans as we add about 400 million toxic waste into water body annually. Other activities of humans have led to an increase in green house gas emissions which can be the major cause of a lot of species going into extinction.
The species of organisms that went into extinction during the PETM event was solely as a result of carbon and climate change and about 1 million species were lost but today, humans are doing a lot of damage to the ecosystem that we fear for another possible event as now we have disease, pollution, and land use. If this event doesn't happen at once, our activities are still leading to the extinction of a lot of organisms.
REFERENCE
https://www.ipbes.net/how-did-ipbes-estimate-1-million https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2007GC00178 https://www.nature.com/articles/s41467-022-33390-x https://www.iucnredlist.org/about/background-history https://www.nature.com/articles/news.2011.498 https://oceanservice.noaa.gov/facts/population.html https://files.ipbes.net/ipbes-web-prod-public-files https://theconversation.com/new-map-shows-that-only https://www.eea.europa.eu/en/analysis/indicators/ocean-acidification https://openknowledge.fao.org/server/api/core/bitstreams https://www.climate.gov/news-features/understanding-climate https://foodtank.com/news/2016/09/protecting-disappearing-livestock-breeds/ https://press.un.org/en/1995/19951205.fao3628.html