1.5˚C vs 2.0˚C

© Adam Dederer
Fascinating Facts

To avoid the worst impacts of climate change, scientists warn that average global temperatures should not be allowed to rise more than 1.5˚C above pre-industrial levels. 

We will hit 1.5˚C within the next two decades, whatever happens to emissions.

Even at this level we will see significant impacts. But a rise in temperature above 1.5˚C could lead to even more drastic changes affecting hundreds of millions of people, and an increased risk of extinction for the world’s species.

What is the impact on biodiversity of another 0.5˚C?

At 1.5˚C

Alpine species migrate upwards on mountain slopes due to warming

6% of insects
4% of vertebrates
8% of plants
Lose half their climate-determined range. 

Shifts in insect pollinators ranges with unknown implications 

Range of marine species shifts to higher altitudes

70-90% decline in coral reefs

One ice free Arctic summer every 100 years

At 2.0˚C

Alpine species adaption to warmer temperatures limited

18% of insects
8% of vertebrates 
16% of plants
Lose over half their climate-determined range

1.5 to 2.5 million km of permafrost could thaw

Ocean acidification further impacts marine species

Almost 100% decline in coral reefs

One ice free Arctic summer every 10 years

It's not just nature that will be impacted 

Flood risk rises from 100% increase to 170%

1 billion people will be exposed to severe heatwaves every 5 years at 1.5°C; that increase to 2.7 billion at 2°C

350 million urban residents exposed to severe drought by 2100, becomes 410 million 

We can also expect lower economic growth, particularly in low-income countries at 2°C vs 1.5°C.

Governments across the world agreed to try to limit warming to 1.5°C above pre-industrial levels in the Paris Agreement to avoid the worst impacts of climate change and secure a liveable future. 

The latest science shows that we have to cut emissions much more, and much faster - we need to reduce them by 43% by 2030 (just seven years away!) to limit warming to 1.5°C.