Ocean Shore at Point Reyes, California, H Graem © 2005 |
Sea-level rise from the melting of polar ice sheets would be a devastating impact of global warming upon life on earth.
Projecting the extent
of such a rise 200 years in the future is difficult, given the
variables involved. However, each new scientific discovery points to an
increased rate of glacier melt and consequent sea level rise.
By the year 2100, polar warming may reach levels similar to those of around 125,000 years ago. Sea level was about eight (8) meters above modern
levels at that time. Both the Greenland Ice Sheet and portions of the Antarctic Ice Sheet may be vulnerable.
The record of past ice-sheet melting indicates that the rate of
future melting and related sea-level rise could be faster than widely
thought. A scenario contemplating a combination of melting from the
Greenland ice sheet as well as that of West Antarctica could bring about a sea level rise of six (6) meters or more.
Changing coastlines worldwide due to alternative future sea level changes can be demonstrated through the internet. One site, flood.firetree.net enables
the viewer to experiment and view the effect of alternative sea level
rises around the planet. The University of Arizona's
Department of Geosciences has a site showing the impact of sea level rise on some areas in the eastern USA. Climate Central created an interactive map comparing the potential impacts of sea level rise under different conditions for vulnerable areas around the earth.
The satellite images below demonstrate the potential impact on five
(5) different coastal areas of a 6 meter (20 feet) rise in sea level.
The scenario assumes a failure of leading industrial nations, such as
the United States, and emerging industrial giants, such as India and
China, to seriously reduce emissions of the "greenhouse gases" linked
to global warming.
Sources for changed shoreline were USGS map contour lines (in the case of the Bay Area), the University of Arizona, Climate Central, and Firetree.
Sources for changed shoreline were USGS map contour lines (in the case of the Bay Area), the University of Arizona, Climate Central, and Firetree.
Today Future
Bohai and Yellow Seas - The most impacted areas of China would be around the Bohai Sea and the Yellow Sea coast to the south. This is the location of some of China's largest cities. |
Ganges Delta - The Bay of Bengal along the coast of India and Bangladesh would be drastically affected by sea level rise - with the Ganges Delta and its population of millions most heavily impacted. |
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