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Sea level rise is settled fact

June 26, 2012 by Leave a Comment

“Some scientific conclusions have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of being found wrong is vanishingly small. Such conclusions are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities … strong evidence on climate change underscores the need for actions to reduce emissions and begin adapting to impacts.”
America’s Climate Choices, U.S. National Academy of Science, National Research Council, 2011

Climate change is taking place and poses considerable risks for us. Among these risks are the detrimental impacts related to sea level rise. And for those of us along the Atlantic coast the impacts may hit sooner rather than later. According to a recently published study by researchers with the U.S. Geological Survey (USGS), sea levels from Cape Hatteras to Cape Cod (a 620-mile Atlantic coast ‘hot spot’) are rising more rapidly than anywhere on Earth – at the speed of three to four times faster than the global average. The study found that since 1990, sea levels have risen approximately 0.08 inches (2 millimeters) to approximately 0.14 inches (3.7 millimeters) a year along the ‘Atlantic coast hot spot’ while the global average for the same time period was 0.6 millimeters to 1 millimeter per year.

The study also noted that sea levels will rise 9 inches by 2030, 18 inches by 2050, and four-and-a-half feet by 2100 globally. Experts at the USGS, as well as other scientists, agree that this increase is due to climate change and other factors. However, according to Asbury Sallenger, the USGS oceanographer who led the study, “sea levels will rise an additional 8 inches to 11 inches in the Atlantic coast hot spot”. Just last week the National Research Council noted that sea levels along California will rise one foot in the next twenty years. Sinking land masses along the California coast and climate change was said to be the cause of that sea level rise.

But what is the cause of the additional increase of 8 inches to 11 inches in sea level rise along the ‘Atlantic coast hot spot’? This can be attributed to the slowing of Atlantic currents by the influx of freshwater into the salty Atlantic Ocean. Melting glaciers from the Greenland Ice Sheet send freshwater into a conveyor belt current (known as the Atlantic Meridional Overturning Circulation) which cause variations in temperature, salinity, and the speed of currents all of which affect sea level rise as warming oceans expand.

Ultimately, this study proves that sea levels have risen since 1990 regardless of the cause. It also provides a call for communities along the Atlantic coast to start planning for sea level rise as many densely-populated cities (Boston, Providence, New York City, Philadelphia, Baltimore, and Norfolk-Virginia Beach) can be found along the ‘Atlantic coast hot spot’ and could see an increase in damages from storm surge.

Here is a list of 50 Things to Reduce Climate Change that will help reduce emissions that attribute to sea level rise. After all, it is not just the impacts from sea level rise, but our health, rainfall, agricultural crop yield, energy supply, as well as other beautiful natural ecosystems that are all affected by climate change.

USGS Researchers used long-term data from tidal gauges along the coast and computer simulations designed at calculating the effects of climate change for their study. The study was published in the journal Nature Climate Change.

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