More than 1,700 American cities and towns – including Boston, New York, and Miami – are at greater risk from rising sea levels than previously feared, a new study has found.
By 2100, the future of at least part of these 1,700 locations will be “locked in” by greenhouse gas emissions built up in the atmosphere, the analysis published in the Proceedings of the National Academy of Sciences on Monday found.
The survey does not specify a date by which these cities, or parts of them, would actually fall under water. Instead, it specifies a “locked-in” date, by which time a future under water would be certain – a point of no return.
Because of the inertia built into the climate system, even if all carbon emissions stopped immediately, it would take some time for the related global temperature rises to ease off. That means the fate of some cities is already sealed, the study says.
“Even if we could just stop global emissions tomorrow on a dime, Fort Lauderdale, Miami Gardens, Hoboken, New Jersey will be under sea level,” said Benjamin Strauss, a researcher at Climate Central, and author of the paper. Dramatic cuts in emissions – much greater than Barack Obama and other world leaders have so far agreed – could save nearly 1,000 of those towns, by averting the sea-level rise, the study found.
A flooded New Orleans following Hurricane Katrina, showing Interstate 10 at West End Boulevard. Photo by: U.S. Coast Guard, Petty Officer 2nd Class Kyle Niemi.
“Hundreds of American cities are already locked into watery futures and we are growing that group very rapidly,” Strauss said. “We are locking in hundreds more as we continue to emit carbon into the atmosphere.”
A recent study, also published in PNAS by the climate scientist Anders Levermann found each 1C rise in atmospheric warming would lead eventually to 2.3m of sea-level rise. The latest study takes those figures, and factors in the current rate of carbon emissions, as well as the best estimate of global temperature sensitivity to pollution.
For the study, a location was deemed “under threat” if 25% of its current population lives below the locked-in future high-tide level. Some 1,700 places are at risk in this definition. Even if bar is set higher, at 50% of the current population, 1,400 places would be under threat by 2100.
The list of threatened communities spans Sacramento, California – which lies far from the sea but would be vulnerable to flooding in the San Joaquin delta – and Norfolk, Virginia. The latter town is home of America’s largest navy base, whose miles of waterfront installations would be at risk of being locked in to future sea level rises by the 2040s. The Pentagon has already begun actively planning for a future under climate change, including relocating bases.
About half the population of Cambridge, Massachusetts, across the Charles River from Boston and home to Harvard and MIT, could be locked in to a future below sea level by the early 2060s, the study found. Several coastal cities in Texas were also vulnerable.
But the region at highest risk was Florida, which has dozens of towns which will be locked by century’s end. The date of no-return for much of Miami would be 2041, the study found. Half of Palm Beach with its millionaires’ estates along the sea front would be beyond saving by the 2060s. The point of no return for other cities such as Fort Lauderdale would come before that.
“Pretty much everywhere it seems you are going to be under water unless you build a massive system of dykes and levees,” Strauss said.
Global average absolute sea level rise between 1870 and 2008. Image by: EPA.
(07/30/2013) Rapid thawing of the Arctic could trigger a catastrophic “economic timebomb” which would cost trillions of dollars and undermine the global financial system, say a group of economists and polar scientists. Governments and industry have expected the widespread warming of the Arctic region in the past 20 years to be an economic boon, allowing the exploitation of new gas and oilfields and enabling shipping to travel faster between Europe and Asia.
(07/08/2013) Warmer ocean temperatures will increase the frequency and intensity of tropical cyclones, typhoons and hurricanes in “most locations” this century, concludes a new study based on simulations using six global climate models.
(07/02/2013) Australia’s huge coal industry is a speculative bubble ripe for financial implosion if the world’s governments fulfill their agreement to act on climate change, according to a new report. The warning that much of the nation’s coal reserves will become worthless as the world hits carbon emission limits comes after banking giant Citi also warned Australian investors that fossil fuel companies could do little to avoid the future loss of value.
(06/26/2013) Sources of campaign contributions to members of Senate suggest Congress will be unlikely to take action on comprehensive climate legislation, indicates data collected by MapLight, a group that tracks money’s influence on politics.
(06/25/2013) Five years after being elected president and six months after winning a second term, President Obama today gave his first speech devoted solely to climate change and announced several executive actions to begin weaning the United States (historically the largest emitter of greenhouse gases) off fossil fuels. At Georgetown University today, Obama stated that his administration would expand renewable energy projects on federal lands, raise energy efficiency standards on appliances, and, most importantly, limit carbon pollution from both existing and new power plants, which represent about 40 percent of the U.S.’s emissions. Obama also noted that the U.S. would spearhead global efforts to combat climate change which is pushing sea levels higher, melting glaciers and sea ice, exacerbating fires, imperiling species, and worsening extreme weather worldwide.
(06/24/2013) After a colder-than-average spring, Alaska is suffering a sudden and record-breaking heatwave. Temperatures on Monday, June 17th hit a stunning 96 degrees Fahrenheit (35 degrees Celsius) in Talkeetna, Alaska, just below the state’s highest temperature ever record of 98 degrees Fahrenheit in 1969. On the same day, NASA’s Terra Satellite’s Moderate Resolution Imaging Spectroradiometer (MODIS) took a rare image of a cloud-free Alaska.
(06/19/2013) Migratory shorebird populations are at great risk from rising sea levels due to global climate change, warns a recent paper in Proceedings of the Royal Society B. These birds play an important role in the distribution of nutrients within wetland and coastal ecosystems, and their loss could have unknown consequences for the rest of the world.