Saturday, September 21, 2019

What Are The Concepts Of Geoengineering Environmental Sciences Essay

What Are The Concepts Of Geoengineering Environmental Sciences Essay Climate change is already affecting the inhabitants, economies, and environment of all regions of the world. Scientific evidence now clearly indicates that human activities such as fossil fuel burning and deforestation have initiated significant climatic change. These anthropogenic activities produce greenhouse gases emissions into the atmosphere, which heat up the atmosphere causing global warming. The impacts of global warming, which are mostly linked with extreme climate events, are mostly dangerous and are expected to continue and intensify in the future. Today, climate policies for global warming are mostly focused on the mitigation of greenhouse gases emissions through regulation. Yet, concerns regarding the slow progress on achieving global emission reductions and uncertainties as to whether regulation can solve global warming, have led some of the worlds scientific and political groups to suggest the possibility of directly manipulating the Earths climatic feedback system (Ra lston, 2009). Such a deliberate, large-scale manipulation of the environment is called Geoengineering (Greencarcongress.com, 2009). The idea of geoengineering is to mitigate the effect of fossil fuel burning on the climate through high-efficiency technologies whether by removing carbon dioxide in the atmosphere, or by reflecting sunlight away from the Earth. The proposed projects include capturing carbon dioxide from ambient air, enhancing weather system, injecting sulphate aerosol into the stratosphere, locating sunshades on the Earths surface, and launching reflective materials into the atmosphere, just to name a few (The Royal Society, 2009). Despite the hopeful sound of these geoengineering proposals, scepticism about whether they are scientifically possible, politically feasible, and ethically justifiable remains. Although there still remain the potential of devastating risks, such as drought in Africa and Asia, ozone depletion, and other unexpected consequences, the deployment of geoengineering presents scientific, political, and ethical challenges to addressing climate change. One of the most significant challenges posed by geoengineering is the scientific issue. While not all scientists agree with the concept of geoengineering, there is the challenge as to whether developing and deploying geoengineering projects on a massive scale are scientifically practicable. Although there are some current technologies that allow these projects, most of them are technically unproven and potentially dangerous to the environment. Given such uncertainties, the scientific soundness of geoengineering has been brought into question. Its not only ethicists and policy makers who question its practicability but also scientists themselves dismiss this idea as infeasible and risky given the scale at which most projects must be instituted and the associated catastrophic consequences. Many still doubt its applicability. For example, the National Academy of Sciences committee on science, Engineering, and Public Policy commented that engineered countermeasures on climate change must first be evaluated before implementation and clear cut understanding on the direct effects and potential side effects, risks and ethical issues must be sought. Some scientists have argued that some of the effects of these technologies are short-term and may be turned-off but others may have long-term effects yet we still cant rely on our current range of scientific experience. Economists in various parts of the globe are working hard to develop least-cost and optimal paths in geoengineering development. Some of their attempts have minimal scientific interest with limited policy and practical value. The main reason for it is because today we have inadequate knowledge on geoengineering risks and costs. It transpires that outputs of cost modelling developed by economists end up being determined by uncertain input assumptions. There is limited cost-benefit climate impact assessment that is simple and economically focused that can provide results relevant to the current policies. Economic analysis on whether to do emissions mitigation or geoengineering is inappropriate (Barret, 2007). This clearly means that more economic research is required so that policy decisions on geoengineering can be made. It is estimated that costs of conventional mitigation may be 1% or 2% of the global GDP and this is almost 1 trillion annually. This is the amount of money that is re quired to avoid risks of current emissions approaching 10GtC/yr. the carbon price corresponding to this is $100 per tone. Costs of SRM (solar radiation management) methods require 1 trillion annually in order to be affordable. CDR (carbon dioxide removal) methods costs would be comparable to carbon mitigation costs of $100/tonne of carbon. Its difficult to establish estimates of costs for geoengineering technologies. There are only tentative estimates available for the methods to be applied (Robock, 2009). Greatest challenge in deployment of geoengineering methods is the political and legal issues associated with governance but rather not in technical and scientific issues. Pre-existing national mechanisms may be sufficient for some of the methods like ambient air capture. For others like ocean iron fertilisation current international mechanisms though relevant still require modification. Some of the methods requiring trans-boundary activity and have trans-boundary effects require nations to have new international mechanisms. One method requiring new international mechanisms is space-based mirrors and stratospheric aerosols. Before deployment of such methods such as solar radiation management and carbon dioxide removal, there must be appropriate governance mechanisms and this call for analysis to determine whether existing national, regional and international mechanisms are appropriate to manage geoengineering. Ethical considerations are a must even if we have to seek ways to minimize risks of global warming. There are debates whether geoengineering is warranted ethically and some arguments of this seek to extend moral concern towards nonhuman environment. For example, people have to conquer natural forces threatening their survival. Adaptation to effects of global warming like mega-storms and rising sea levels shows that nature is the victor in the man-nature struggle. Geoengineering projects apply technology to overcome nature and to convert natural environments to built environments. Some have argued that it is a moral imperative to conquer nature. There is an ethic of control requiring humans to manage natural environment while treating soils, fauna, atmosphere and flora as resources for use. Those who are for ethic of restraint however resist temptation of natural environment exploitation. Geoengineering methods are though to be aligned with an ethic of control but not merely that of r estraint. On ethical matters, there appears to be a conflict between the present and the future generations. Some of the projects favoured by current generations with idea that they will not affect the future generations are however not aligned with interests of these projects. There is insufficient scientific certainty that may prevent adoption of cost effective measures to evade causing harm to future generations and degradation of environment. Anthropogenic GHG emissions continue to rise since rich nations undertake projects without consent of poorer ones while the poorer nations with a right to development may initiate their projects. The debate remains on collective actions while the levels of emissions are still increasing (Robock, 2009). Geoengineering technologies may slow down the global hydrological cycle (Hoffman, 2010). Several studies have proposed geoengineering schemes that will reduce amount solar radiation that is absorbed by planet earth. From sunshade geoengineering schemes, it has been reported that global warming as a result of increasing concentration of carbon dioxide can be mitigated intentionally through manipulation of amount of sunlight absorbed through the climate system. Insolation reductions aimed at offsetting the global temperature increase usually lead to a decreased global average precipitation. This happens because solar forcing more effectively drives global mean evaporation changes compared to amount of carbon dioxide forcing which is of the same magnitude. Insolation changes come with larger changes in surface radiative fluxes and this is compensated by larger changes in sensible and latent heat fluxes. Hydrological cycle is so sensitive to temperature adjustment through the changes in insolation. This is a clear indication that geoengineering technologies through alteration of solar forcing offsets hydrological and temperature changes. Geoengineering technologies have serious effects on ecosystems. The mitigation effects are somehow ineffectual in reduction of anthropogenic carbon dioxide emissions. Coral reefs are one of the most sensitive ecosystems to climate change. They are two groupings of solar radiation; long-wave carbon dioxide removal and shortwave solar radiation management. Some of these techniques only reduce some of the effects but create other problems. They dont affect carbon dioxide levels and thus rarely address its side effects like ocean acidification that is important for coral reefs. Solar radiation is important for survival and growth of coral, therefore solar radiation management is not appropriate for coral reefs ecosystems (Royalsociety.org, 2009). Calcifying marine organisms like crustaceans, corals, and molluscs are adversely affected by these technologies. Marine life ahs millions of lives that can be destroyed through the current technologies aimed at checking the climate change. Thoug h they are good remedies to reduce effects on humans, marine life has been put at risk. Even iron filings that are used to enhance growth of phytoplankton are still not good to marine life 100%. Aerial spraying, aerosol emissions, chemtrails or the so called cirrus clouds have been created through geoengineering technologies. These chemicals have heavy metals that may cause dementia symptoms associated with Alzheimers disease. Chemtrails affect localized weather where a clear blue sky may be turned into a hazy overcast. Some of the chemicals from chemtrails have high concentrations of Lead (8.2 ppm) and Barium (6.8 ppm). There are traces of other elements such as selenium, cadmium, chromium and arsenic which are so toxic. Exposure to Barium can cause chest and stomach pains and weakening of the human immune system (Robock, 2009). Barium causes asthma and its a powerful suppressant of the immune system. This is weather modification that has also affected the water supplies and agricultural crops. Weather modification using geoengineering technologies may in the long run affect all ecosystems through reduction of water supplies, crop production, water availability and changing the agricultural crops production cycles. Due to the increasing effects of global warming and the greenhouse gases, use of geoengineering technologies is a great idea. This is because even if there are side effects we cant just ignore the new inventions by our scientists as we continue to suffer. Its one of the methods that we can apply in minimizing the high concentration of carbon dioxide in our atmosphere. We cannot however use it as a substitute but we need to have it as a preventive measure when the concentrations of carbon dioxide are so high in the atmosphere. We should use geoengineering when we have to reduce adverse effects of climate change. It is important that we use geoengineering in controlling greenhouse gases like harmful methane which is capable of staying in the atmosphere for a very long period of time. Reduction of such gases in the atmosphere is less painful than reduction of carbon dioxide. Technologies to perform such prevention measures are already in existence and are economically and politically ea sy to handle. Personally, I believe we need to have more research on this topic before we decide to use it on the large scale (Schwartz, 2009).

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