Scientists warn on rising seas

Posted: 10 September 2002

Author: Don Hinrichsen

As the earth's climate changes, due largely to human-induced increases in the atmospheric concentration of heat-trapping gases such as carbon dioxide, concerns about altered rainfall patterns and rising sea levels continue to surface.

A report* by the Intergovernmental Panel on Climate Change (IPCC), concludes that the world's sea level could rise by as much as one metre within just 80 years.

That is an outside estimate, which may not happen (see feature article Rising Seas and Changing Currents), but such a dramatic rise could affect up to one billion people living along the world's coastlines. It would be especially damaging in the tropics, where warmer water expands faster than in more temperate regions.

A one-metre rise would inundate coastal areas throughout the world:

  • In Bangladesh, three million hectares would be inundated, displacing 15-20 million people.
  • In India, 600,000 hectares would be submerged, driving 7 million people from their homes.
  • Over 3.4 million hectares would be waterlogged in Indonesia, pushing at least two million people out of low-lying areas.
  • Vietnam would lose 500,000 hectares of land in the Red River Delta and another 2 million hectares in the Mekong Delta, displacing roughly 10 million people.
  • In the Philippines up to one-quarter of the entire population could be affected, with 5-10 million displaced.
  • Nearly all of the Maldives' 1,196 coral islands would disappear off the map, making refugees out of the entire population of 300,000.
  • In Egypt 2 million hectares of the Nile Delta would disappear, displacing 7-10 million people.

The US National Oceanic and Atmospheric Administration (NOAA) reported in August 2000 that the world's oceans were warming much faster than anticipated, contributing to sea level rise and global climate change. Over the past several decades the world ocean has warmed by 0.3 degrees Centigrade, representing a huge increase in the heat content of the ocean.

Ocean warming, including coral bleaching and rising seas are already impacting on coastal populations and ecosystems.