The climate is generally warm and pleasant, though hotter than Fiji due to the northerly location. The waters lapping these shores are among the warmest in the world, and those of the interior lagoons are several degrees warmer again.
The mean annual temperature is 29° C and the average annual rainfall 3,000 mm (the southernmost atolls are somewhat wetter). Rain falls on more than half the days of the year, usually heavy downpours followed by sunny skies. The trade winds blow from the east much of the year.
Strong west winds and somewhat more rain come between November and April, the hurricane season. Tuvalu is near the zone of hurricane formation, and these storms can appear with little warning and cause considerable damage. Tuvalu's climate is warming faster than anywhere else in the South Pacific, and this has led to an increase in the frequency and severity of hurricanes.
Hurricane Bebe in 1972 was the first since 1894. Hurricanes Gavin and Hina spawned by the El Niño phenomena in 1997 eroded an estimated seven percent of Tuvalu's landmass! In June 1997 Hurricane Keli struck Niulakita with 180 kph winds, the first hurricane ever recorded in the South Pacific in June.
Coral bleaching occurs when an organism's symbiotic algae are expelled in response to environmental stresses, such as when water temperatures rise as little as 1°C above the local maximum for a week or longer. Bleaching is also caused by increased radiation due to ozone degradation, and widespread instances of bleaching and reefs being killed by rising sea temperatures took place in French Polynesia, Cook Islands, and Fiji during the El Niño event of 1998. A "hot spot" over Fiji in early 2000 caused further damage.
The earth's surface has warmed 1°C over the past century and by 2080 water temperatures may have increased 5°C, effectively bleaching and killing all of the region's reefs. Ocean acidification is gaining momentum as carbon dioxide released by the burning of fossil fuels is absorbed by the world's seas. Corals, plankton, and algae respond negatively to acidification, accelerating the destruction of the reefs. By 2050 coral bleaching will become an annual event.
Continue to Climate: Climate Change »