Is global warming likely to cause an abrupt collapse of global biodiversity?

Recent studies show that risks to biodiversity do not appear progressively. Instead, as the climate warms up in a certain area, most species will be able to cope for some time. Until a threshold is crossed when a large proportion of species will suddenly be confronted with conditions they have never experienced before. This is not a gentle slope, but a series of cliffs hitting different areas at different times.

The results show that with uncontrolled warming, more than 15% of biological communities - defined as aggregations of several species - would exceed their critical threshold by 2100. This figure falls to only 2% under warming compatible with the Paris Agreements. However, in both cases, the ecosystems with the greatest biological diversity are highly threatened. Coral reefs come to mind among others.

A recent article in The Guardian also confirms these studies. It states, among other things that:

40% of world’s plant species at risk of extinction

In 2019, Nic Lughadha reported that 571 species had been wiped out since 1750, although the true number was likely to be much higher.

And on top of that, the UN revealed last week that the world’s governments failed to meet a single target to stem biodiversity losses in the last decade.

The results underline the urgent need to mitigate climate change by immediately and drastically reducing greenhouse gas emissions. This could help save thousands of species from extinction. Keeping warming below 2°C effectively flattens the risk curve for biodiversity, allowing more time for species and ecosystems to adapt. Whether by finding new habitats, changing their behaviour, or with the help of human-led conservation efforts.

A Dangerous Game - source unknown