Climate change could halve crop yields and submerge property worth $500 billion this century
Former New York Mayor Mike Bloomberg is now Ban Ki-moon’s UN climate envoy (Pic: NYC Mayor’s Office)
By Gerard Wynn
US cities and business were unprepared for climate change which would become rapidly more dangerous without urgent cuts in carbon emissions, found a report published on Tuesday by the “Risky Business Project”.
The study attempted to add greater regional detail to existing climate projections, to mobilise action to cut emissions as well as to prepare for unavoidable changes.
“Our findings show that, if we continue on our current path, many regions of the U.S. face the prospect of serious economic effects from climate change,” said the report, “The Economic Risks of Climate Change in the United States”.
“If we choose a different path – if we act aggressively to both adapt to the changing climate and to mitigate future impacts by reducing carbon emissions – we can significantly reduce our exposure to the worst economic risks from climate change, and also demonstrate global leadership on climate.”
Climate studies usually find great difficulty in forecasting regional changes, because of the complexity of atmospheric and ocean physics, and the uncertainty surrounding future carbon emissions and other pollution.
For example the recent U.S. National Climate Assessment, produced by federal government agencies, documented only a broad sweep of expected climate changes this century.
Tuesday’s analysis used expertise from researchers at Rutgers and Berkeley universities, and was led by the Mayor of New York Michael Bloomberg and the former US Treasury Secretary Henry Paulson.
PRESS CONFERENCE: Bloomberg and Paulson launch study
“The Risky Business Project is designed to highlight climate risks to specific business sectors and regions of the economy, and to provide actionable data at a geographically granular level for decision-makers.”
“It is our hope that it becomes standard practice for the American business and investment community to factor climate change into its decision-making process.”
The study described expected regional changes, focusing on heat waves, storm surges and sea level rise, from the near to the long term.
Within the next 15 years, it predicted that the annual cost from coastal damage along the eastern United States and Gulf of Mexico would rise by more than $7 billion, as a result of sea level rise and more powerful storms and hurricanes.
It forecast falling yields of staple crops in the southern United States, and a rising bill from growing energy demand during hotter summers.
Underwater
Looking further ahead, crop yields could more than halve in the Southeast, lower Great Plains, and Midwest.
And the report projected massive losses of coastal property as a result of sea level rise.
“If we continue on our current path, by 2050 between $66 billion and $106 billion worth of existing coastal property will likely be below sea level nationwide, with $238 billion to $507 billion worth of property below sea level by 2100.”
“Property losses from sea level rise are concentrated in specific regions of the U.S., especially on the Southeast and Atlantic coasts, where the rise is higher and the losses far greater than the national average.”
By the end of the century, the hottest part of the country would see several months each year with daytime temperatures exceeding 95 degrees Fahrenheit (35 degrees Celsius), given current trends in carbon emissions.
“Over the longer term, during portions of the year, extreme heat could surpass the threshold at which the human body can no longer maintain a normal core temperature without air conditioning. During these periods, anyone whose job requires them to work outdoors, as well as anyone lacking access to air conditioning, will face severe health risks and potential death.”
American hedge fund manager and philanthropist Tom Steyer is one of the backers of this new study (Pic: Climate Week NYC/Flickr)
Such forecasts echoed the recent reports of the UN’s Intergovernmental Panel on Climate Change.
The IPCC reviews the published science on climate change every six years or so.
In its latest assessment of climate impacts, published in March, the IPCC reported that at higher levels of carbon emissions this century, parts of the globe may become uninhabitable.
“Core body temperatures will reach lethal levels under sustained periods of wet-bulb temperatures above about 35C,” said the chapter of the IPCC report focusing on health impacts.
“Working conditions are hazardous at lower thresholds. The U.S. military, for example, suspends all physical training and strenuous exercise when the wet bulb globe temperature exceeds 32C.”
“Global mean warming of roughly 7°C above current temperatures would create small land areas where metabolic heat dissipation would become impossible. An increase of 11-12C would enlarge these zones to encompass most of the areas occupied by today’s human population.”
Under a scenario where carbon emissions were double or more today’s levels, global average surface temperatures would rise by 3-8C by 2100, compared with pre-industrial levels, the IPCCC estimated.