Curious Climate schools
Curious Climate schools

How many species will we lose if we cannot get climate change under control?

How much biodiversity have we lost already due to climate change and what will the impacts be in the future?

Plants and animals are threatened by lots of things like habitat loss from land clearing, or being hunted, fished or harvested. On top of these pressures are climate change impacts.  

Because there are so many interacting threats to biodiversity, we haven’t yet attributed many species’ extinctions only to climate change. Species that we have lost to date from climate change are species that occur only in one place, so they are very rare, and those places are exposed to immediate climate impacts such as flooding and sea level rise.  

The Bramble Cay Melomys was an Australian rodent that occurred only on one island in the Torres Strait. In 2016, it became the first recorded species extinction attributed to human induced climate change. The small sand island it lived on was affected by sea level rise and storm events. The extinction record by the State of Queensland said that extinction was caused by "ocean inundation of the low-lying cay, very likely on multiple occasions, during the last decade, causing dramatic habitat loss and perhaps also direct mortality of individuals" (1). There are likely other species that have been lost to a similar fate.  

The Bramble Cay Melomys, in 2016 declared extinct on Bramble cay, where it had been endemic, and likely also globally extinct, with habitat loss due to climate change being the root cause. Creative Commons: Ian Bell, EHP, State of Queensland.

The IUCN Red List of species is the best source for understanding global threats to species. Expert have listed climate change as a cause of decline for 19% of all species listed as near threatened or threatened. Climate change impacts that threaten species include increases in storms, flooding, extreme temperatures, drought, and sea level rise.  

As an example – Hooded seals are a species threatened directly by climate change. Their population has dropped in abundance by 90% in the northeastern Atlantic Arctic over the last 20 years. This decline is attributed to loss of sea ice which has reduced the number of places available for resting and raising pups.  

Researcher with a hooded seal pup on ice in the Gulf of St. Lawrence. Photo: NOAA, via Wikimedia Commons

Looking into the future – One study estimated that if we follow our current, business-as-usual trajectory of climate change, which is projected to lead to a 4.3°C temperature rise, climate change would threaten one in six species (16%). This could as much as double our extinction rates.  

This is one of many reasons why people are calling for governments to limit climate change to 1.5°C, by ‘decarbonising’ our economy – or stopping emissions of CO2. If we do this, we can reduce the rates at which plants and animals become extinct. 

climateFuturesUnviersity of TasmaniaTas Gov Sponosored
We acknowledge the Palawa/Pakana people, the Traditional Custodians of lutrawita/Tasmania. We recognise and respect their collective wisdom and knowledge about country and change.
(c) copyright 2024 University of Tasmania.
About this site
closearrow-circle-o-downchevron-downkeybarsellipsis-v