Trillions.
Even if CO2 emissions were to be drastically cut down starting today, the world economy is already committed to an income reduction of 19% until 2050 due to climate change, a study published in Nature finds. These damages are six times larger than the mitigation costs needed to limit global warming to two degrees.
Based on empirical data from more than 1,600 regions worldwide over the past 40 years, scientists at the Potsdam Institute for Climate Impact Research (PIK) assessed future impacts of changing climatic conditions on economic growth and their persistence.
“Strong income reductions are projected for the majority of regions, including North America and Europe, with South Asia and Africa being most strongly affected. These are caused by the impact of climate change on various aspects that are relevant for economic growth such as agricultural yields, labor productivity or infrastructure,” says PIK scientist and first author of the study Maximilian Kotz.
Overall, global annual damages are estimated to be at 38 trillion dollars, with a likely range of 19–59 trillion dollars in 2050. These damages mainly result from rising temperatures but also from changes in rainfall and temperature variability. Accounting for other weather extremes such as storms or wildfires could further raise them.
These damages are compared to a baseline of no climate change and are then applied against overall expected global growth in gross domestic product, said study lead author Max Kotz, a climate scientist. So while it’s 19% globally less than it could have been with no climate change, in most places, income will still grow, just not as much because of warmer temperatures.
For the past dozen years, scientists and others have been focusing on extreme weather such as heat waves, floods, droughts, storms as the having the biggest climate impact. But when it comes to financial hit the researchers found “the overall impacts are still mainly driven by average warming, overall temperature increases,” Kotz said. It harms crops and hinders labor production, he said.
“Those temperature increases drive the most damages in the future because they’re really the most unprecedented compared to what we’ve experienced historically,” Kotz said. Last year, a record-hot year, the global average temperature was 1.35 degrees Celsius (2.43 degrees Fahrenheit) warmer than pre-industrial times, according to the U.S. National Oceanic and Atmospheric Administration. The globe has not had a month cooler than 20th century average since February 1979.
In the United States, the southeastern and southwestern states get economically pinched more than the northern ones with parts of Arizona and New Mexico taking the biggest monetary hit, according to the study. In Europe, southern regions, including parts of Spain and Italy, get hit harder than places like Denmark or northern Germany.
Only Arctic adjacent areas — Canada, Russia, Norway, Finland and Sweden — benefit, Kotz said.
It also means countries which have historically produced fewer greenhouse gas emissions per person and are least able to financially adapt to warming weather are getting the biggest financial harms too, Kotz said.
The world’s poorest countries will suffer 61% bigger income loss than the richest ones, the study calculated.
“It underlies some of the injustice elements of climate,” Kotz said.
The study shows that the economic harms over the next 25 years are locked in with emission cuts producing only small changes in the income reduction. But in the second half of this century that’s when two different possible futures are simulated, showing that cutting carbon emissions now really pays off because of how the heat-trapping gases accumulate, Kotz said.
If the world could curb carbon pollution and get down to a trend that limits warming to 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial times, which is the upper limit of the 2015 Paris climate agreement, then the financial hit will stay around 20% in global income, Kotz said. But if emissions increase in a worst case scenario, the financial wallop will be closer to 60%, he said.