A surprise was uncovered by the study. Evidently, the sea level on the Atlantic coast from Cape Cod to Cape Hatteras, which includes New York, Norfolk and Boston, has risen by 2 to 3.7 millimeters (0.08 to 0.15 inches) per year. This is up to four times faster than the global average (between 0.6 and one millimeter per year).
Figure 2: SLRDs for 60-yr time series at gauge locations across North America from Hotspot of accelerated sea-level rise on the Atlantic coast of North America
The report presents
. . . evidence of recently accelerated SLR in a unique 1,000-km-long hotspot on the highly populated North American Atlantic coast north of Cape Hatteras and show that it is consistent with a modelled fingerprint of dynamic SLR. Between 1950–1979 and 1980–2009, SLR rate increases in this northeast hotspot were ~ 3–4 times higher than the global average
The melting of the Greenland Ice Sheet is dumping freshwater into the ocean, which disrupts the Atlantic current circulation. As the current stalls, the surface water warms and expands, backing up water behind it, causing sea levels to rise.
The USGS report is based on actual tide level measurement. Other studies have shown a similar hotspot using climate models.
Another concern is that even if we stopped releasing greenhouse gases today, it will take years for any impact to be felt. In the meantime, low-lying delta areas, barrier islands and entire island nations will disappear from sight.
Global warming is real and is causing visible changes in sea levels. Despite claims that global warming is a myth, the truth is out.
The blog, Posing Facts, posted an interesting article about 15 places under threat due to global warming (May 2010).The obliteration of Lohachara island, in India's part of the Sundarbans where the Ganges and the Brahmaputra rivers empty into the Bay of Bengal, marks the moment when one of the most apocalyptic predictions of environmentalists and climate scientists has started coming true . . . (The Independent, Sunday 24 December 2006).
You may be interested in viewing the glaciers past and present in One Consequence of Global Warming (October 2009).