Potential threat of Indo-Pak nuclear war on Ocean acidification

India and Pakistan are currently walking a thin line due to the disputed territory of Kashmir. Both countries are not likely to initiate a nuclear conflict without provocation. India has declared that it will not resort to the use of nuclear weapons unless initially attacked with biological or chemical weapons; while Pakistan stated that it would only use nuclear weapons if it failed to halt an invasion via conventional means or in response to a nuclear attack. However, the two countries have undergone four conventional wars in 1947, 1965, 1971, and 1999 and the possibility of conventional wars becoming nuclear with the current issue of Kashmir at hand cannot be completely ruled out.
Utilizing a range of climatic models, research has demonstrated that in addition to regional consequences, nuclear warfare will also result in global anomalies; one of these anomalies goes by the name of ‘nuclear winter’; this term is used to describe a process in which nuclear weapons will cause fires, injecting smoke into the upper troposphere, and where subsequent lofting will shift the soot-particles into the stratosphere. The soot particles will absorb sunlight, leaving our beautiful planet colder and darker.
Research has shown that even a minor nuclear conflict may result in global climatic consequences such as altering the state and circulation of the atmosphere, increasing the extent of sea ice in both hemispheres, and minimizing the crop yield in lands distant from the origin of the crisis.
Just like on land and in the atmosphere, nuclear conflict is bound to have a negative impact on the oceans as well; however, these consequences have been studied to a lesser extent. The temperature in the marine environment is key to various physical, chemical and biological processes in the ocean. Furthermore, sunlight is crucial for various processes and organisms including phytoplankton – the base of the marine food web. Research predicts that a potential India/Pakistan nuclear conflict that lofts 5 Tg of black carbon particles into the stratosphere will decrease the average sea surface temperature by 0.8 °C; according to a recent study, these activities will also decrease the phytoplankton productivity by 5-15%.
At minimum, 700 million tonnes of carbon dioxide would be released into the atmosphere following a nuclear conflict; therefore, another recent area of interest is how nuclear warfare might alter the chemical state of the ocean. Changes in the Ocean’s carbonate chemistry are predominantly important due to its role in ocean acidification. Currently, 30-40 % of carbon dioxide gets dissolved into the ocean. After absorption, carbon dioxide forms carbonic acid. This carbonic acid converts into bicarbonate releasing hydrogen ions and then carbonate, further releasing hydrogen ions. This increase in hydrogen ions in the ocean is the main factor contributing to the increasing acidity of the oceans.
Geological history tells us that marine organisms can be put under threat if exposed to an acidic environment. The consequences incorporate drops in the organisms’ metabolic rate and drops in their immune response to other harmful pathogens such as parasites or bacteria. Changes in pH can also cause the destruction of coral by triggering chemical reactions that result in an overall drop in carbonate ions.
Carbonate ions are important for corals as they combine with calcium ions to form calcium carbonate – the building blocks for the skeletons of various marine organisms such as corals, mollusks, and crabs. When the number of hydrogen ions in the oceans increases, the available carbonate combines with these hydrogen ions to form bicarbonate, thus limiting the amount of carbonate for marine organisms to utilize. Corals, mollusks, and crabs are not the only ones affected by this; single-celled organisms such as foraminifera and coccolithophores, which are the base of marine food webs and are very important in the marine ecosystem also suffer as a result.
These creatures also consist of shells, which require calcium carbonate as a building block. Scientists have also studied the effect of increasing the amount of carbon dioxide above a tank of seawater and have found that this increases the rate at which the skeletons of these organisms dissolve; this has been observed in organisms such as starfish and sea urchins despite the protective covering over their calcium carbonate skeletons, and is particularly problematic in larval stages.
Organisms which do not have calcium carbonate skeletons and shells are also victim to increased acidity; for example, excess carbon dioxide can accumulate in the body fluids of organisms such as fish and squid, affecting their immune response – a phenomenon known as hypercapnia. Studies have also shown that excess carbon dioxide can make it difficult for baby clownfish to distinguish between friends and foes.
Furthermore, changes in the water’s chemistry can alter the acoustic properties of water. This has dire consequences for creatures which use echolocation including marine mammals such as whales and dolphins. Carbon dioxide also increases Ocean noise – a domain in which the human race has already caused enough damage via other means. Acidic environments can also interfere with the construction of ear bones and balance organs, such as statoliths. On the bright side, increase in carbon dioxide levels would enhance the growth of sea grass; however, the exact implications of this are unknown.
Although the first thing that comes to mind while thinking about the travesties of a nuclear war is the direct havoc on human life, the direct consequences to the environment as a result and the indirect effects of these consequences to human and non-human life cannot be overlooked. The magnitude of the long term consequences of a nuclear war between India and Pakistan due to failure in resolving the Kashmir issue through alternative means are immense, and although in the future, most of us may be able to perceive how it has affected life and the environment on land, the potential devastation on the oceans should not be disregarded.