Major cities along the East Coast of the United States such as Baltimore, Boston, Philadelphia and New York are at higher risk of floods as sea level rise has accelerated much faster compared to the rest of the world.
Tide-level data analysis conducted through the coasts of North America have showed rapid and unexpected rise in sea level - up to 3.8 millimeters a year - from 1950 to 2009 in the 1000-kilometer coast between North Carolina to the Boston Area. Additionally, annual sea level rise over the rest of the globe averaged at 0.6 to 1 millimeter over the same time period.
The study, conducted by U.S. Geological Survey scientists, supported the notion that sea levels are expected to rise worldwide as time passes by due to global warming melting ice and causing sea level water expansion. Though rises in sea level in areas differ according to a number of factors (such as seawater salinity and temperature differences, ocean currents and the Earth's shape), the stark difference of the rise in the East Coast alarmed the scientists, calling the densely populated area a "sea level rise hotspot".
Though apparently it is not just the studies that show sea level rise. According to USGS-contracted oceanographer and study co-author Peter Howd, even older residents living in the area for decades testify that the water is coming higher than it ever has before in winter storms.
Why the U.S. East Coasts sea level rise is more rapid than the rest of the world remains a mystery, although scientists have speculations. One of these is that it could be that the fresh water coming from the melting ice in Greenland is disturbing the North Atlantic currents, thereby slowing the flow of the Gulf Stream and will cause the sea levels on the East Coast to rise. They also have yet to discover what the underlying cause of the sea level rise is, as human activity as the cause remains unclear.
Though the focus of the sea level rise study is set on the East Coast, climate modeler Jianjun Yin of the University of Arizona warns that it is not just these cities that have to bear the effect of the rise as the country's northeast coast "is flat and even gradual sea level rise would result in swift retreat of the shorelines and will seriously impact wetland habitats."