Computer simulations over the past few years have shown major cities worldwide disappearing underwater by the end of this century as oceans encroach. Now a new study explaining mysterious East Coast floods in the U.S. during 2009 and 2010 may provide something of a window into the future.
The sea rose four inches from New York to Newfoundland during those two years because of a change in the ocean’s circulatory patterns and intensity, according to a study released on February 24.
“Independent of any hurricanes or winter storms, the event caused flooding along the northeast coast of North America,” said a statement from the University of Arizona, which led the study reported in the journal Nature Communications. “Some of the sea level rise and the resulting flooding extended as far south as Cape Hatteras.”
Led by University of Arizona assistant geosciences professor Jianjun Yin a co-author, and geosciences doctoral candidate Paul Goddard, the lead author, the research team connected the unusual sea-level jump to changes in ocean circulation—the first study to do so, the university noted.
Goddard first detected the two-year-long sea-level spike by reviewing monthly tidal-gauge records for the entire Eastern Seaboard, the University of Arizona said, some of them dating back to the early 20th century. Over those 100-plus years, UA said, only 2009 and 2010 registered such a marked increase.
"The sea level rise of 2009-10 sticks out like a sore thumb for the Northeast," Goddard said in the UA statement. Moreover, "the thing that stands out is the time extent of this event as well as the spatial extent of the event."
Also co-authoring the study were Stephen Griffies and Shaoqing Zhang of the National Oceanographic and Atmospheric Administration’s (NOAA) Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey, with NOAA funding the research, UA said.
The researchers pulled in other variables, compiling a broader picture to determine the cause and predict future trends. Among them was an analysis of the Atlantic Meridional Overturning Circulation (AMOC), by other researchers that showed a 30 percent drop in the current’s strength during the same time period, starting a mere two months before the sea level began spiking, the UA said.
As far as future increases, the team found that the current rate of carbon dioxide increase in the atmosphere will likely boost the frequency of such sea-level jumps. Such results are in keeping with those of previous studies, including one in 2012 from the U.S. Geological Survey (USGS) that found sea levels rising faster in the Northeast than elsewhere on the planet.
Another study from last year showed that summer high tides had increased by a good two feet along the Gulf of Mexico coast, according to Live Science. Findings like this also dovetail with the predictions of a series of climate-change maps crafted by Martin Vargic, an amateur graphic designer from Slovakia and published online at Halcyon Maps about a year ago. The maps depict a world devoid of ice caps, with a 260-foot sea level rise.
“I created these maps both to raise awareness about the global warming and also because nobody has yet done this on such a scale,” Vargic told the UK Daily Mail in April 2014.
“According to recent studies, there is enough ice in Earth’s polar caps to cause about 250-300 feet (80–100m) rise of the sea level,” he said on his website, Halcyon Maps. “Result of such an event would be catastrophic to human civilization and Earth’s biosphere.”