Ocean Warming and Coral Bleaching

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Global warming is caused by the accumulation of carbon dioxide and other heat-trapping gasses in the atmosphere. These gases act as a blanket, preventing the heat of the sun to escape through our atmosphere.

This is primarily due to fossil fuel burning and deforestation and many scientists believe that this is causing sea surface temperatures to rise. Ocean warming is extremely dangerous to coral organisms, which are very sensitive to changes in temperature. Increased water temperatures, which may be linked to global warming, can cause mass coral bleaching.

This occurs when coral polyps, stressed by heat or ultraviolet radiation, expel the algae that live within them. These algae, called zooxanthellae (zo-zan-THEL-ee) normally provide the coral with up to 80% of its energy, making zooxanthellae essential for coral survival. The algae are also normally responsible for the color of coral, so when they are expelled, the coral appears white or "bleached." There is a chance that bleached coral can recover if conditions return to normal quickly enough. However, in the face of other human-induced pressures, corals have become vulnerable. In many cases, bleached coral colonies die.

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Dive in Bunaken National Marine Park,North Sulawesi

Bunaken Island is part of the Bunaken National Marine Park, which has some of the highest levels of marine biodiversity in the world. Scuba diving attracts many visitors to the island. Bunaken is located at the north of the island of Sulawesi, Indonesia. It belongs administratively to the municipality of Manado.

The Bunaken National Marine Park was formally established in 1991 and is among the first of Indonesia's growing system of marine parks. The park covers a total surface area of 890.65 km², 97% of which is overlain by sparkling clear, warm tropical water. The remaining 3% of the park is terrestrial, including the five islands of Bunaken, Manado Tua, Mantehage, Nain and Siladen. Although each of these islands has a special character, it is the aquatic ecosystem that attracts most naturalists.

The waters of Bunaken National Marine Park are extremely deep (1566 m in Manado Bay), clear (up to 35-40 m visibility), refreshing in temperature (27 to 29 °C) Pick any of group of interest - corals, fish, echinoderms or sponges - and the number of families, genera or species is bound to be astonishingly high. For example, 7 of the 8 species of giant clams that occur in the world, occur in Bunaken. The park has around 70 genera of corals; compare this to a mere 10 in Hawaii. Although the exact number of fish species is unknown, it may be slightly higher than in the Philippines, where 2,500 species, or nearly 70% of all fish species known to the Indo-western Pacific, are found. Other sides of Bunaken Island.