The Indian Ocean - Michael Pearson [216]
Another deleterious, albeit controversial, aspect of a more integrated world is that environmental problems are often global in scale. Global warming, mostly a consequence of rich world industry releasing greenhouse gasses, is claimed to be causing a rise in the level of the ocean. Average global temperatures went up about ½° C in the twentieth century, and the sea level rose between 4 and 10 inches over the same period. Records show that 1998 was the warmest year ever since temperatures began to be recorded 150 years ago. As an Indian Ocean consequence, the Maldives, where most of the 1,200 islands are no more than a metre above sea level, are likely to be under water within thirty years.76
Coral reefs are important tourist attractions, and form a fascinating natural underseascape. They have been under threat for at least fifty years. In the late 1960s Jacques Cousteau worried that coral reefs were in danger as the purity of the water declined. Equally threatening, conchs were being taken to sell their shells to tourists, but they are the deadly enemy of a kind of starfish which is very destructive to coral: consequently coral suffers. More recently global warming has had a catastrophic effect on coral reefs all around the Indian Ocean. At least half of the total died in the two years up to 2000. Coral cannot tolerate a rise in sea temperatures of more than 1 or 2°C for more than a few weeks, yet in the Seychelles in 1998 the temperature was 3°C above seasonal norms for several weeks. The results have been far-reaching. It is estimated that in 1998–99 the death of the coral, or its bleaching to an unattractive monochrome, cost the Maldives' economy about $US 36 million in 1998–99, a result of the impact on tourism and on local fishers.77
There is atmospheric pollution also. In 1999 a haze of air pollution covered some 10 million square kilometres of the Indian Ocean. It was caused by burning fossil fuels from India, China and southeast Asia blown over the ocean by the northeast monsoon. The result was acid rain and lower temperatures. In 1997 the warming of the western Indian Ocean is considered to have caused excessive rain over East Africa, and consequently a rise in the level of Africa's lakes, and severe flooding on the Nile. In many of the littoral countries indiscriminate clearing of forests has had very adverse effects. It is estimated that for ecological stability one-third of any given area needs tree cover, but in India this is down to 10 per cent. This leads to greater flooding, but also the reverse: as the forest cover diminishes, rainfall declines.78
Threats to the environment are not that new. The ecology of St Paul and Amsterdam islands was radically changed around 1800 by imported and then feral pigs, deer and rabbits, so that, as a contemporary mourned, 'Once they were green, now they are brown, desolate and despoiled.'79 The dodo was rendered extinct by European hunting and introduced animals. In the early 1950s Cousteau was at the Aldabra islands, which consist of four small atolls. He found thousands of giant land tortoises, some with shells five feet long. Herbivores, they graze on grass and seem to have no enemies. Then he went on to a neighbouring island and found heaps of tortoise skeletons. All