Due to their environmentally friendly nature, methane hydrates (MH) are widely recognized as a form of sustainable energy. Several of methane hydrates’ qualities make it an energy resource worth exploring in order to meet growing energy needs in an environmentally conscious way. For example, burning methane hydrates produces fresh water. In fact, methane hydrates are widely recognized as one of the cleanest fuel sources because their combustion merely generates energy and water. This quality could in turn offer one possible solution to worldwide shortage of water. By comparison, coal and crude oil combustion does not generate nor release fresh water, but rather consumes large amounts of it. Methane hydrates are acid-free, contain fewer impurities than natural gas, and they release fewer carbon emissions than either crude oil or coal. In fact, methane hydrate extraction could change the landscape of the global energy supply. Due to the icy structures of both methane and water, the extraction of methane volumes from methane hydrate deposits could simultaneously enable carbon sequestration while replacing the methane with carbon dioxide. Alternatively, the methane may be combusted on-site to generate electricity, while the remnants may be re-injected into the hydrate deposits for Carbon capture and storage (CCS). However, methane hydrates are believed to be mostly located offshore, which raises questions about the environmental impact of its extraction. Although methane hydrates initially appear to be a cleaner energy source than traditional crude oil and gas, there has not been any large-scale commercial extraction. This is because of the uncertainties of its related technology, particularly regarding the environmental risks these technologies may pose. Such risks include greenhouse gas emissions, water quality change, interference with fishery, seafloor disturbance, underwater sediment resuspension, increase in turbidity, marine sediment change, seafloor occupation, seafloor subsidence, submarine landsides, disrupt methane entry to sediment, methane leakage from sediment, lightening, and greenhouse gas discharge. In some instances, offshore methane hydrates extraction may cause increased sea levels, earthquakes, and even tsunamis which would impact the environment and a broad array of coastal communities. Methane hydrates only exist in certain parts of the sea, where temperatures are cold, and pressure is high. For the most part, these areas of the world are already suffering from negative environmental effects and are precariously balanced on the edge of disaster. There is a looming possibility that methane hydrate’s very structure may not be very stable either during or after the exploratory process. This means that there is a high risk that MH may be transformed from a solid to gaseous methane, which is one of the most polluting kinds of greenhouse gas and even more damaging than carbon dioxide. Any leakage of methane would exacerbate global warming and cause an increased sea level and temperature. Additionally, the exploratory and extraction processes may damage the maritime and oceanic landscape. Methane may provoke higher speeds of microbiological oxidation and cause consumption of oxygen in a short period of time that can create a hostile environment for the survival of sea life. In sum, offshore methane hydrate extraction imposes a real threat to the environment and the benefits must be carefully weighed against the risks before projects for its extraction are attempted.
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