The gravest danger facing Tuvalu and the other atolls and reefs of Oceania is the greenhouse effect, a gradual warming of the earth's environment due to fossil fuel combustion and the widespread clearing of forests.
By the year 2030 the concentration of carbon dioxide in the atmosphere will have doubled from preindustrial levels. As infrared radiation from the sun is absorbed by the gas, the trapped heat melts mountain glaciers and the polar ice caps. In addition, seawater expands as it warms up, so water levels could rise almost a meter by the year 2100, destroying shorelines created 5,000 years ago.
A 1982 study demonstrated that sea levels had already risen 12 centimeters in the previous century; in 1995 2,500 scientists from 70 countries involved in the Intergovernmental Panel on Climate Change commissioned by the United Nations completed a two-year study with the warning that over the next century air temperatures may rise as much as 5°C and sea levels could go up 95 centimeters by 2100.
Not only will this reduce the growing area for food crops, but rising sea levels will mean salt water intrusion into groundwater supplies—a troubling prospect if accompanied by the increasing frequency of droughts that have been predicted. Coastal erosion will force governments all around the Pacific to spend vast sums on road repairs and coastline stabilization.
Increasing temperatures may already be contributing to the dramatic jump in the number of hurricanes in the South Pacific. For example Fiji experienced only 12 tropical hurricanes from 1941 to 1980, but 10 from 1981 to 1989.
After a series of devastating hurricanes in Samoa, insurance companies announced in 1992 that they were withdrawing coverage from the country.
In 1997 and 1998 the El Niño phenomenon brought with it another round of devastating hurricanes, many hitting Cook Islands and French Polynesia, which are usually missed by such storms.
The usual hurricane season is November to April, but in June 1997 Hurricane Keli struck Tuvalu—the first hurricane ever recorded in the South Pacific in June.
Hurricane Zoe, which swept across Tikopia and Anutu in the Solomon Islands in late December 2002, was the most powerful tropical storm ever recorded in the Pacific. Two weeks later, northern Fiji was battered by Hurricane Ami, the worst storm to hit Fiji in a decade.
As storm waves wash across the low-lying atolls, eating away the precious land, the entire populations of archipelagos such as Tokelau, Tuvalu, and the Tuamotus may be forced to evacuate long before they're actually flooded. The construction of seawalls to keep out the rising seas would be prohibitively expensive and may even do more harm than good by interfering with natural water flows and sand movement. On coral atolls seawalls can't hold back rising lagoon waters which seeps through crevices and cracks. The highest point of land in Tuvalu is only five meters above sea level and parts of Funafuti are already flooded every February by spring tides as high as 3.2 meters.
Unfortunately, those most responsible for the problem, especially the United States, Canada, and Australia, have strongly resisted taking action to significantly cut greenhouse gas emissions, and new industrial polluters like India and China are sure to make matters much worse. And as if that weren't bad enough, the hydrofluorocarbons (HFCs) presently being developed by corporate giants like Du Pont to replace the ozone-destructive chlorofluorocarbons (CFCs) used in cooling systems are far more potent greenhouse gases than carbon dioxide.
What to expect? A similar increase in temperature of just 6°C at the end of the Permian period 250 million years ago eventually wiped out 95 percent of species alive on earth at the time and it took 100 million years for species diversification to return to previous levels. At the moment the people of Tuvalu are living on borrowed time and New Zealand has promised to accept the entire population as environmental refugees when the islands are finally overwhelmed by the sea.