Without effective action to reverse the upward curve in greenhouse gas emissions, parts of the southern United States could experience a decline of more than 20% in economic activity due to global warming by the end of the century. , according to a new analysis of regional economic risks. of climate change.
The county-by-county analysis shows that the poorest regions of the country would be hit hardest and that the nation as a whole could see up to 6% of its GDP cut by the end of this century.
The analysis is based on a high emissions trajectory that does not take into account future voluntary efforts to reduce emissions under the Paris climate agreement.
By breaking down the economic impacts at the regional level, the authors show that regions of the country that are already economically fragile could be the hardest hit. This means that if the whole world adopted the Trump administration’s laissez-faire approach, the impacts on the poor would not only be felt in the developing world, but in the richest nation on the planet.
The Pacific Northwest and New England, parts of the country with strong regional economies, would likely see a slight increase in economic activity, while the Gulf Coast and southeastern states would be particularly hard hit.
The yawning gap between the richest and the poorest – income inequality – would only widen, thwarting one of the key goals of sustainable economic development.
“You have the poor getting poorer”
A loss of 6% of GDP for the whole country is expected by the last decade of the 21st century according to the study, published Thursday in the journal Science. Regional economic damage in the southern and southern Midwest due to climate change is expected to outweigh the benefits of global warming.
âYou have these very uneven impacts of climate change, where you have winners and losers, but the losers are in parts of the country that already tend to be poorer today,â said lead author Solomon Hsiang. , professor of public policy at the University. of California, Berkeley.
“It worsens economic inequalities in the United States, where the poor get poorer and the rich get richer,” he said.
Hsiang and his colleagues looked at the financial impact of warming temperatures at the county level, looking at agriculture, crime, coastal storms, energy consumption, human mortality, and work. They assumed that greenhouse gas emissions will continue at their current rate, raising the average global temperature by up to 4.5 Â° C above pre-industrial levels by the end of the century.
The commitments made so far for the non-binding Paris climate agreement, including those made by the United States government, which intends to withdraw from the agreement, could limit warming to around 3 Â° C. The aim of the treaty is to raise ambition and keep the rise in temperatures well below 2 Â° C.
Focusing on the high emissions rate shows the risks facing the current U.S. economy, the study’s authors said.
The study also considered moderate and low emission scenarios when calculating the effects on U.S. GDP as a whole, but not as part of its county-by-county analysis. If the world meets or exceeds the commitments made under the Paris climate agreement, the negative effect on U.S. GDP by the end of the century would vary from 0.1% to around 4%, depending on the authors.
Calculation of impacts, county by county
In the county-by-county analysis, the biggest economic impact in the calculations came from changes in mortality due to warming temperatures. Warming is reducing mortality in cold northern counties and increasing death rates in warm southern regions. The study relied on figures from the EPA which place the value of an individual life at $ 7.9 million after adjusting for inflation.
Energy use follows a similar pattern, increasing in the south to power additional air conditioning during the hot summer months, but decreasing in the northern areas as winters become more moderate. Together, reduced mortality and lower energy use largely explain the economic gains seen in northern Maine, where counties are expected to experience an estimated 5-10% increase in GDP.
A similar pattern is seen in Mineral County, Nevada, a high altitude county with relatively cool temperatures. The county is expected to experience the highest potential GDP growth in the country, although the study’s authors say the data for this county is in part an anomaly based on the location of the weather station used for the sparsely populated county. compared to where the residents actually live.
Work is also negatively affected by extreme heat. When temperatures soar, as recently happened in the southwest, outdoor jobs such as construction and farming and factory jobs with limited air conditioning suffer.
The study also found that agriculture in the Midwestern grain belt would be significantly affected by warming temperatures.
âAcross the US Midwest, we’re seeing a reduction in agricultural productivity that looks roughly the same reduction we saw during the Dust Bowl,â Hsiang said.
Some say the damage is already happening.
âRight now when people think of climate change, they think of a polar bear on a piece of ice that is melting,â said Robert bullard, professor of town planning, environmental policy and administration of justice at Texas Southern University, who was not involved in the study. “It is happening, but it is also happening in these places where entire communities sink or burn from forest fires or are destroyed from severe hurricanes, tornadoes and increasingly flooding.” . “
In regions and counties affected by climate change, minority and low-income communities bear and will continue to bear the brunt of the economic damage, Bullard said.
“Some populations are more at risk given the geographic location due to all kinds of policies and planning and in some cases geographic and racial red lines where people are being pushed to low lying areas prone to flooding. and areas not covered by dikes, âhe said. âThe people who have the least will lose the most. If you lose 20 percent of what you have, and what you have may not be much, it is a big hit.