Coccolithophores
Coccolithophores are microscopic plants involved with marine calcification. This is the mechanism by which atmospheric carbon dioxide is dissolved in water and subsequently converted into calcium carbonate and the hard shells of marine life. The shell is an exoskeleton being a hard covering on the outside of an inner soft body. Creatures (like humans) have an endoskeleton inside soft tissue. Both provide a hard and protective framework.
Whatever the truth, increases in the global atmospheric CO2 level upsets the delicate balance of the chemistry involved in calcification and the ability of marine organisms to manufacture their own protective exoskeleton. This also undoubtedly has ramifications regarding climate change theories. Calcification is critical to coral reef creation and maintenance and key organisms at the beginnings of the food chain on which all other sea creatures depend.
Ironically, the process of calcification, or soaking up CO2 to form calcium carbonate in exoskeletons has taken millions of years. Human activity and the construction industry has generated multimillion tonnages of CO2 simply by heating limestone in the production of concrete. Carbon dioxide dissolves in water to form carbonic acid and the averaged warming sea temperature means that more CO2 is liberated into the global atmosphere. The possible causes for the increase in carbon dioxide levels are many and a great variance will be apparent in the source location. Wind, however, will eventually move the invisible gas all around the globe. The ability to utilise carbon dioxide as a calcification source will depend on warming seas and the warmer the temperatures of the sea, the less CO2 that is available. It will consequentially reside in the atmosphere and not in the oceans.
In terms of a sink, the more CO2 that is dissolved in water and subsequently removed in the calcification process, the less that will end up lost to the atmosphere as the sea warms up, but melting Arctic or Antartctic ice will to some extent cool the water. The warming sea
results in elevated atmospheric CO2 and the alleged human activity that is the primary cause of global warming is reasonably challenged. The natural ecosystems developed over millions of years to balance global CO2 between the sea and atmosphere is certainly threatened by mankind unceasingly spewing out of this gas.
Another temporary helper can be seen in the Coccolithophore and gives mankind a possible respite to facilitate a moderation in activity that will ultimately have a disastrous effect on the ability to survive. Coccolithophore 'blooms' are so large that they are visible from outside the Earth atmosphere and for photosynthesis to occur depend on dissolved CO2. Oceans are naturally alkaline though increased CO2 that is dissolved will increase the acidity as carbonic acid is generated. Although the sea does not become acidic, it does become less alkaline as the pH (puissance d'Hydrogène = hydrogen power or strength) moves to a lower value. Carbonic acid itself partially dissociates into hydrated hydrogen ions (hydronium ion) and bicarbonate ions in further chemical equilibria.
It appears that coccolithophores thrive in increased levels of CO2, but warming seas result in less CO2 being retained by the oceans. To balance this, the CO2 concentration is reduced by its removal in the calcification process allowing more CO2 to be retained in solution at the same temperature. Melting ice fields cool warming waters until global temperatures cool again in the thousands-of-years-long cycle and the ice eventually reforms. This cyclical balancing depends on the level of CO2 not being increased without interruption. Any sponge can only support so much water before it becomes saturated. So also is the argument regarding atmospheric and sea concentrations of CO2 gas. As the level of CO2 increases, saturation point will ultimately be reached if it hasn't already.
Regardless of the mechanism by which CO2 levels increase, ecosystems will not be able to help slow mankind's seemingly unstoppable race towards self-extinction. The ecosystems that have supported life on Earth for millions of millennia will also be destroyed by sentient man.
posted by Louis Brothnias @ 1:42 AM
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