Wednesday, December 27, 2006

Global Warming: Rising Seas creates 70,000 Climate Refugees

Rising seas attributed to human induced global warming have submerged Lohachara island, once the home to 10,000 people. Unhinhabited Suparibhanga has also vanished, while the inhabited island of Ghoramara has lost two thirds of its area to the rising seas in the Bay of Bengal.

While we were all distracted by Christmas festivities, this sober news on the impact of climate change was published in The Independent (UK), about the inundation of various Sundarban islands in the Indian part of the delta region of the Ganges and Brahmaputra river, where they empty into the Bay of Bengal.

The region is considered remote and researchers at Calcutta's Jadavpur University discovered the submergence through examining satellite photos of the area. According to the report in the Independent, Dr Sugata Hazra, director of the university's School of Oceanographic Studies, said that there are now a dozen "vanishing islands" in India's part of the delta.

70,000 Climate Refugees

People from Lohachara island and the disappearing Ghoramara island have fled to Sagar, which has also lost 7,500 acres of land to the sea. Up to a dozen islands, home to 70,000 people, are immediately threatened by the rising seas inundating homes and livelihoods.

In Bangladesh, 17 million people live less than one metre (three feet) above sea level.

Rising Sea levels and submergence of habitat also pose a threat to the area's 400 Bengal tigers.

Rising Sea Level a Global Problem

Rising sea levels have already caused the people of the Carteret Islands near New Guinea to start evacuating their homes. They were thought to be the first climate refugees caused by rising sea level. Other island nations such as the Maldives, Marshall Islands, Tuvalu, and Kiribati are imminently threatened.

According to Mike MacCracken, chief scientist for climate change programmes at the Climate Institute, a Washington think-tank, "It's often presented as a problem only for developing nations. (But) developed countries will be very much at risk because so much infrastructure is at sea level."

The problem will also manifest itself in the first world. Coastal areas like the east coast of North America and particularly Florida are vulnerable to rising sea levels. A Satellite photo from NASA/JPL gives a dramatic demonstration of how Florida's low topography, especially along the coastline, make it especially vulnerable to flooding associated with storm surges.

The problem will also affect many coastal cities around the world. Flooding from rising sea levels could cause massive damage to infrastructure, including agricultural production.

New York could be subject to "flooding by major storms would inundate many low-lying neighborhoods and shut down the entire metropolitan transportation system with much greater frequency," according to Vivien Gornitz, a scientist from NASA's Goddard Institute for Space Studies (GISS) and Columbia University.

With sea level rise, New York City faces an increased risk of hurricane storm surge.

Prof Stefan Rahmstorf, a leading climate expert at the Potsdam Institute for Climate Impact Research, has estimated there may be a sea level change above 1990 levels of between 0.5 and 1.4 metres by 2100. He said that there was a close correlation between the amount of global warming and the rate of sea level change: the warmer it gets, the faster sea levels rise. Historical data from the 20th century shows that global sea level rose by 20cm (8in) over the last century, and is in accord with Rahmstorf's estimate.

A report quoted in The London Telegraph says "Even a small increase in sea level will increase the risk of serious flooding in the Thames Estuary. We need to integrate our thinking about these extreme scenarios into decisions we make about more probable flood management today," said the report authors, Dr Nassos Vafeidis of the University of the Aegean, Greece, and Prof Rob Nicholls of the University of Southampton. Rising sea level will have a major impact on the Thames Estuary, where 1.25 million people currently live, 1.5 million commute and there are assets worth up to £100 billion.

* Independent (UK) 23 Dec 2006 - Disappearing world: Global warming claims tropical island
* >London Telegraph 27 Dec 2006 - London-on-Sea: the future of a city in decay
* NASA 25 Oct, 2006 - NASA Looks at Sea Level Rise, Hurricane risks to New York City
* Wikipedia: Sundarbans
* MIM 30 Sep, 2006 - Carteret Islands Evacuated Due to Rising Sea Level
* MIM 13 Jan, 2005 - Climate Change and Development Issues for Island States
* NASA - Ganges River Delta Photo