Environmental Effects Of Ocean Acidification

Ocean acidification, as its name suggests, is the decrease in PH value of the seawater. It is caused primarily by the uptake of carbon dioxide in the atmosphere. Oceans were known to balance the components of atmospheric carbon dioxide and mitigate climate change. However, the current rate of intake of carbon dioxide is about 100 times faster than ever before (Oceana, 2012). The rate of absorption is so fast that it alters the chemistry of seawater. Since the beginning of industrial revolution, about one third of the carbon dioxide emitted has been absorbed by the ocean. The rate of change is too fast for marine species to evolve and adapt to the new challenging environment. Ocean acidification not only poses threats to marine ecosystem, affects

It is related to various anthropogenic emissions, which could hardly be reduced. Burning of fossil fuels, unsustainable fishing practices, nutrients run-off due to change in land use for agriculture and livestock production and possibly other acidic chemicals improperly discharged by industries may all affect marine environment. Carbon dioxide is not the only source of pollution. There are some other auxiliary non-CO drivers like nitrogen oxides and sulphuric compounds that cause ocean acidification (Ryan P. Kelly, Margaret R. Caldwell, 2013). It is inefficient and impractical to tackle with the pollutants all at once. Ocean acidification and global warming are different results of climate change. The two share many common sources of the problem. However, people have more consensus on global warming as compared to ocean acidification. To alleviate the current trend of global warming, varieties of laws and actions have been in place. Even so, the current efforts to reduce greenhouse gas emission are still ineffective due to the lack of responsibility and stewardship. It poses more difficulty to shift our focus on a more complex and less understandable

Despite the enhancement of international collaboration, regional efforts have to be made by implementing adaptation and mitigation measures. In recent year, new geo-engineering methods are used to tackle with ocean acidification. For example, iron fertilisation helps to promote the growth of phytoplankton, which fixes carbon dioxide in the atmosphere by photosynthesis (Long Cao • Ken Caldeira, 2010). This helps to increase primary production; hence more carbon dioxide can be removed. Another commonly mentioned method is to dump a large quantity of limestone into ocean. Calcium carbonate helps with ocean acidification in two ways. One is to balance the PH of ocean and mitigate the impacts of ocean acidification. The other is to increase carbon sequestration with calcium oxide after thermal decomposition (Greg H. Rau, 2008). None of the adaptation and mitigation methods target at reducing carbon dioxide emission. They are adopted to delay the process of ocean acidification, while at the same time, build up the resilience of local areas towards ongoing climate change. However, though these schemes are theoretically probable, they have not been applied to a large scale. Firstly, the operation is economically and environmentally costly. Massive amount of energy is required to extract, produce and process iron and limestone. Moreover, the unsustainable exploitation of natural resources might create more environmental