Coral is an essential element of the oceanic living system of planet Earth. It serves as the base of the pyramid of life in shallow salt water of the tropics, by virtue of the ability of the coral organism to build structures in which many species of living creatures can find food and shelter. The coral organism is a living creature that excretes a hard calcium carbonate exoskeleton in various interesting and beautiful shapes.
Coral is dying all over our planet. This reality promises serious trouble for the human race. When corals die, the hard structures they created eventually erode and fall apart, depriving tropical ocean creatures of the shelter they need to avoid predators. Areas formerly filled with a rich mix of colorful creatures become wastelands with relatively few living creatures. This is not just a problem for tourists wearing scuba tanks. Many millions of humans depend on coral reefs for their economic survival. Humans in the Pacific basin and the Caribbean basin are especially dependent on coral reef fish and crustaceans for their livelihoods. Many areas of coral, including nearly half of all coral in the Caribbean basin, are already dead. The rest of the world’s corals are expected to die within a hundred years in the absence of a new development to reverse the observed mortality trend.
Many scientists are currently engaged in seeking the root cause of coral death. Global warming is considered the chief suspect by many. The theory of how this works is complex. First, humans burn coal and oil to generate heat and energy. The combustion results include greenhouse gasses such as carbon dioxide. The carbon dioxide level in the global atmosphere has gradually risen over the past 200 years. The world ocean gradually absorbs some of this chemical compound. As the carbon dioxide dissolves in sea water, it forms carbonic acid, thereby increasing the acidity of ocean water. The rising acidity interferes with the life cycle of the coral organism, which can no longer derive calcium carbonate from the more acid waters. The corals then die. Actually, “theory” is too soft a term for the science analysis of the ocean acidification process. The data has been counted and the explanation noted. Ocean water is now around 30% more acidic than it was 250 years ago and the process is accelerating.
A secondary threat to coral reefs is the rising level of coastal pollution and physical damage from human activities. In some cases, a convincing case can be made for the idea that pollution, sediment deposits, dynamite fishing, or coral ripping by anchors, have killed or damaged coral reefs in localized areas. However, the damage to coral reefs has been noted on a planetary level, not just a local level. On that basis, the ocean acidification concept is a more convincing explanation for the observed coral deaths and the trend toward complete coral extinction. Since the most likely root cause is global in nature, it is difficult to foresee an easy solution to the coral death problem. Obviously stopping and then reversing the carbon dioxide rise in the world atmosphere would address the problem. But this solution is elusive, as the 7 billion humans currently living have so far wrestled with the global warming problem without success, failing to forge international treaties combatting greenhouse emissions due to the perceived costs of shifting away from fossil fuels. Billions of tons of carbon dioxide care expected to be added to the atmosphere in future years, as non-fossil energy sources such as solar, nuclear, and wind fail to replace fossil fuels in a timely manner.