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Ocean acidification – climate

Fatema Miah:

In the last articles I explained albedo process and oceans are vast actor in the earth and how oceans are effected by Carbondioxide. Here lets talk about ocean acidification. The ocean acidification  caused by carbondioxide as well as other pollution. It is a concern issue.

The earths largest portion of that’s 70% is Oceans and sea. Oceans and sea are effected by Carbondioxide and caused acidification. The aspects of ocean acidification that scientists first started looking at was its impact on calcification. So a large number of marine invertebrates have calcium carbonate skeletons. The oysters, for example, has a really delicate shell which is made out of calcium carbonate. And any shells that you see on a beach are made of  calcium carbonate structure. Other animals such as sea urchins also have calcium carbonates in their skeletons. So calcification is the precipitation of calcium and carbonate ions into the solid shell form. Once it’s formed, the calcium carbonate structure, like this shell, is quite vulnerable to dissolution again unless it’s surrounded by seawater that has saturated calcium carbonate levels in it.

There is another explanation of saturation; the saturation state is the thermodynamic potential of any mineral such as calcium and carbonate to either form a solid or dissolve. So when the sea water becomes under saturated with carbonate ions, the tendency is for these structures to start dissolving. As we’ve learned, when carbon dioxide increases in the ocean, we get a reduction in the carbonate ions because it’s soaking up those hydrogen ions acting as a buffer. So as ocean acidification progresses, the amount of carbonate that’s available for the shells to form  start to decrease. In the process, also the ocean will become under saturated and what’s been monitored  shown the shells and structures being dissolving. The reduced carbonate, the hydrologic acid in seawater actually dissolve our shells.

Previously I wrote about importance of  corals and they are  suffering. Sea corals are also suffering by ocean acidification as well from abusive coral mining. Corals are biggest player in our feedback loop for greenhouse gases and work of photosynthesises.  Oceans are sponge and sea corals suck up large no of carbondioxide.  The heat stress lead to bleaching that coral loose their colour as their photosynthetic symbiont is expelled and leads to starvation. Plastic and oil spill are other sources pollute to sea and oceans and killing marine species.

One quarter of carbondioxide taken up by oceans as ocean is a sponge. Carbondioxide sinks deep i to the oceans. The calcifying organisms and corals are susceptible to change of ocean chemistry and leads to algae. The excess  carbondioxide amount causing rapid acidification  to oceans and making unable for marine organisms to cope therefore causing extinct of marine organisms and corals and adding to warming up so goes back to the feedback loop and it is a negative feedback and effect the thermohaline process and also effects the food chain.

With the water circulation system that mix the water around the world,  the acidification effects worlwide. It is global effecting issue. The focus factor is Carbondioxide that’s needs to be tackle and there isn’t a policy implaced specifically to tackle such.  There isn’t any specific plan implaced for how to tackle ocean acidification issue in Paris aggrement. However, co2 emmission of carbondioxide is the problem and culprit for all effected spheres and the lowering carbon emission plan is the solution for the effected oceans too, to tackle ocean acidification.

There are many action plans to tackle co2 carbondioxide level. In relation to ocean acidification, geoengineering to tackle the co2 carbondioxide emmission is the identified agreed solution to tackle ocean acidification. The geoengineering approach to tackle the ocean acidification involves adding alkaline to the oceans in different ways. There is an explanation by ecologist that carbonate ions acts as natural buffers to acidifications in reaction. If lime stone powder added to the oceans this will dissolve and improve oceans buffer. Lime stone can be mined by using renewable energy with an affordable cost. Such solution can be used to enhance weathering technique.

So far the weathering techniques idea is the only though solution to  minimise the ocean acidification, though not  yet been put in action. Question rose, is it safe to play chemical against chemical? Is that a viable solution to tackle ocean acidification? Would it likely to lead to any other negative reaction?   Fatema Miah, Solihull, uk. fatemamiah@mail.com