dpa
Berlin
A new study warns that catastrophic effects of global warming could cause the worldwide economy to shrink by about 20% by the middle of the century, even if future emissions of greenhouse gases are drastically reduced.
If emissions aren’t reduced, even greater economic damage can be expected, according to researchers at the Potsdam Institute for Climate Impact Research (PIK) in Germany.
The study, published on Wednesday in the journal Nature, calculated annual economic damage from climate change at more than $38 trillion per year if climate-damaging emissions aren’t significantly reduced.
That figure is six times higher than the estimated costs of the measures needed to limit global warming to a maximum of two degrees Celsius above the pre-industrial average, according to the study.
The expected damage varies greatly from region to region. The poorest countries and those least responsible for climate change will be hit the hardest, according to the study.
For the United States and Germany, for instance, the researchers predict that the economy will shrink by 11% by the middle of the century even in a scenario where climate change is limited to two degrees or less, compared to a scenario without climate impacts.
For the calculation, the researchers analysed data from the past 40 years from more than 1,600 regions on how weather extremes have influenced economic growth.
Based on climate models, they calculated how these are likely to affect the economy over the next 26 years.
Damage caused by natural disasters like storms or forest fires, which many researchers believe will be worsened by climate change, are not included in the calculations but could further increase the economic damage. According to the United Nations, efforts so far have fallen well short of what’s needed to limit climate change to two degrees or less.
“High-income losses are projected for most regions, including North America and Europe, with South Asia and Africa being the hardest hit,” wrote Maximilian Kotz, one of the authors of the study.
“These losses are caused by a wide range of economically relevant effects of climate change, such as consequences for agricultural yields, labour productivity and infrastructure.”
Researcher Leonie Wenz pointed out that the expected economic damage is the result of greenhouse gases that have already been emitted, and said that adaptation measures are needed to mitigate those impacts.
“In addition, we must drastically and immediately reduce our CO2 emissions - otherwise the economic losses will be even higher in the second half of the century and will amount to a global average of up to 60% by the end of the century,” said Wenz. The Potsdam team’s current calculations are surprisingly close to the forecasts known as the Stern Report, which economist Nicholas Stern calculated almost 20 years ago on behalf of the British government.
The Stern Report, presented in 2006, predicted that climate change would cause the international economy to shrink by around 20%.
