Should Hansen et al’s research prove to be correct. The situation will be worse than shown
in this article. If the Greenland ice melts, the sea level rise could be 5-7 metres.
SEA LEVEL RISE
Sea level rise can be defined as an increase in sea level caused by global warming through two main processes: the thermal expansion of sea water and the rapid melting of land ice.
Sea level rise is also expected to make coastal cities more vulnerable to extreme weather (such as hurricanes) as well as to destroy important ecosystems such as wetlands and mangroves. Rising sea level inundates low-lying lands, erodes shorelines, exacerbates flooding, and increases the salinity of estuaries and aquifers. Islands are particularly exposed as many are gradually facing the loss of their fresh water supply due to salt-water intrusion. Low-lying coastal areas and deltas (the land where rivers feed into the ocean) house at least 300 million people and are particularly threatened by sea level rise.
Some developing countries are especially exposed to sea level rise due to their low- lying nature and limited financial resources to respond. Among the most vulnerable are countries with large populations in deltaic coastal regions such as Bangladesh, Vietnam, China and Egypt.
The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC 2007) projects an increase of temperature ranging between 1.1 and 6.40 C over the next century, necessarily entailing a reduction of the amount of ice. As a result, sea levels could rise 10 to 23 inches by 2100.
Two populous island nations, the Philippines and Indonesia, have millions who face displacement from their homes from sea level rise. Several small island state nations including the Maldives in the Indian Ocean and the Marshall Islands and Tuvalu in the Pacific could face extinction within this century if rates of sea level rise accelerate.