I suppose that places like Nauru are what we think of as desert islands. It is located in the Pacific Ocean and happens to be the world’s smallest independent republic and probably only has that status because what it has is not of much interest to its neighbours, the nearest of which is 180 miles away.
Having strip mined its phosphate deposits and briefly flirted as a tax haven and money laundering centre, it now fears survival, from manmade climate change. The nine thousand or so inhabitants of Nauru live close to the coast; they have little option because the island comprises only eight square miles. Its highest point is only 61 metres high and the coastal region, where people live, is all at or very close to sea level.
Nauru is part of the Alliance of Small Island States, virtually all of whom are threatened by two effects of climate change. The first threat arises from likely increases in sea levels. Sea level is not a constant thing, but a mean level. It varies from ocean to ocean. The IPCC predict sea level rises this century of between 18 and 69 centimetres, compared with sea level rises of just 17cm from 1840 to 2004, but that prediction specifically excludes the effect of rapid ice melt from the polar regions.
The latest scientific consensus is that there will be a sea level rise of at least on metre this century but these predictions have a 50% chance of being true and the actual sea level rise may be more or less in a longer or shorter time frame.
Those facts and predictions must give some problems to people who inhabit small low lying islands; the offer no comfort. Any sensible government must take account of those predictions and facts in their planning and in their policies; the scenario that they reveal is too dangerous to be ignored. Nauru is not alone in facing threats from rising sea levels. Maldives, which is the lowest lying country in the world, the Marshall Islands, Federated States of Micronesia, Vanuatu, Tuvalu, and Kiribati are all threatened.
Now some of these islands (a small minority as far as studies by the University of Auckland shows) are increasing their land masses. The increase is due to deposits of sediment and coral debris brought by storms and hurricanes, but the increase does not make the islands higher and more resistant to sea level changes. It simply provides them with more land some of which is un-useable.
The second threat to these small island nations arises from climate change itself. Nauru used to have a wet season and a dry season. That no longer appears to be the case. It has suffered from drought, one of which lasted seven years, and the intensity of its storms has increased. The island has also suffered from warming ocean temperatures. As the ocean warms so fish tend to move and fewer fish means less local food for the island inhabitants.
El Nino and La Nina, those Pacific sea oscillations, make it particularly hard to read the tea leaves of climate change in the central Pacific Ocean, so knowing how much of the threat to small island states is due to global warming and how much is due to El Nino and La Nina is hard to determine, but it is likely that all ocean oscillations (including the Gulf Stream) are likely to be affected by global warming.
One thing is certain; the coral reefs are bleaching and dying due to the increased acidity of the ocean.
Coral bleaching has been around for many years but prior to the 1980s all known cases were very minor and occurred in small tide pools or shallow enclosed lagoons cut off from the sea by extreme low tides at noon. Occasionally high rains and floods pushed freshwater over shallow reefs, and this caused bleaching.
In the 1980s bleaching spread dramatically from a few small areas where we could identify the cause (such as a power station discharging heat into the ocean) to areas of the ocean covering up to thousands of kilometres. It is thought that warmer ocean temperatures simply created conditions in which coral reefs could not survive.
The prospects for small island states in the Pacific Ocean do not look particularly rosy. The small island states have given up on persuading the nations that produce high emissions to change their ways and have turned to seek compensation from those nations for their plight. I suppose that for most of the nations that produce high greenhouse gas emissions the small island states are out of sight and very much out of mind, as they continue their business as usual, which will put these small islands states out of business one day.
Filed under: climate change, carbon emissions, global warming Tagged: | climate, coral bleaching, environment, Federated States of Micronesia, IPCC, Kiribati, Maldives, nature, Nauru, rising sea levels, science, sea level rises, small island states, the Marshall Islands, Tuvalu, University of Auckland, Vanuatu