Nonprofit climate news and advocacy group Climate Central has released a series of multi-layered interactive maps designed to illustrate how various levels of sea level rise may affect coastal communities all around the United States.
The group’s latest mapping tool, titled “Mapping Choices,” allows you to enter any zip code or U.S. city and compare — side-by-side — how that site would appear if pollution is allowed to continue “unchecked” versus a scenario in which pollution is heavily reduced.
The majority of scientists who study the issue agree sea level is rising and will continue to rise moving forward, due in part to the melting of the global ice caps, although there is a range of theories on how much.
On one end of the spectrum are researchers like James Hansen, a former lead climate scientist for NASA who estimates sea levels will rise by as much as 10 feet in as little as 50 years.
In contrast, the United Nations’ Intergovernmental Panel on Climate Change has predicted a sea-level rise of between 1-3 feet by 2100, depending on the degree to which carbon emissions are curbed.
Away from the laboratories and halls of academia where many of these estimates are developed, researchers found that sea levels in Casco Bay rose by 5 inches between 2009-2010. And while that local jump may have been a freakish two-year spike, it lends credence to predictions that sea levels may make more bounds upward in the years to come.
The affects of higher sea levels can then be exacerbated by storm surges and high tides, working together to create heavy coastal flooding like what many low-lying Maine communities experienced during last month’s record rainstorm.
The Climate Central tools that illustrate this range of hypotheses best come in the forms of interactive maps released in 2013. You can find the local maps by clicking through the state of Maine in the interactive map at the top of this page or by clicking here.
Climate Central analyst Ben Strauss explains the research behind the 2013 maps this way:
“An international team of scientists led by Anders Levermann recently published a study that found for every degree Fahrenheit of global warming due to carbon pollution, global average sea level will rise by about 4.2 feet in the long run. When multiplied by the current rate of carbon emissions, and the best estimate of global temperature sensitivity to pollution, this translates to a long-term sea level rise commitment that is now growing at about 1 foot per decade.”
For those of you looking for a quicker digestion of the maps, we’ve saved you the trouble of clicking through the interactive map above to research each Maine place highlighted.
We animated the maps for each Maine community so you can watch the waters rise from 1 foot all the way to 10 feet and alter the shapes of the coasts along the way.
The maps also show what percentage of each community’s current homes and residents would be underwater at each stage of sea-level rise, with the most striking numbers coming from Old Orchard Beach, where 27.7 percent of homes and 13.1 percent of the population falling into the Atlantic at the highest predicted levels.
South Portland would see 9 percent of its current homes and 6.8 percent of its residents underwater at the highest sea-level rise estimate, by comparison.
In many of these communities, as you can see below, the most significant change to the coastline comes within the first foot of sea-level rise.
Again, these are animated maps — if you want to slow down and take a closer look at each individual community at each stage of potential sea-level rise, use the interactive map at the top of this page or click here.
Old Orchard Beach
Cousins and Littlejohn islands
(Featured main page images, clockwise from left: The Climate Central map of Portland; Troy R. Bennett photo of a boy walking home in Portland through flood waters resulting from the Sept. 30 record rainstorm; a Natural Resources Council of Maine depiction of Portland’s Back Cove after sea-level rise.)