Friday, September 20, 2019
Global Climate Change as a Socially Relevant Scientific Issue
Global Climate Change as a Socially Relevant Scientific Issue The climate of planet Earth has been subjected to significant changes, particularly in seasonal temperature and weather patterns, since the dawn of the Industrial Revolution, around the year 1750. Since that time, the climate has been increasingly impacted by anthropogenic drivers, such as carbon dioxide and methane production. Increasing concentrations of these gases have led to changes in available habitat for many organisms, extreme weather patterns and sea level rise, as well as effects on the health and economy of the human population. According to the U.S. Environmental Protection Agency, changes in global climate can have dramatic effects on where species can live, how they interact, and the timing of key life events, all of which can have profound effects on ecosystems. For example, one study shows that Northeastern birds that normally spend the winter in the southern United States have been returning north in the spring 13 days earlier than they did 100 years ago (United States Environmental Protection Agency, 2017). Shifts in migration like this can result in limited food availability and changes to breeding cycles. Some species have been shifting their habitable range due to changes in their normal environmental range, causing ecosystem changes along the way. For example, as boreal forests invade the tundra, the habitats of caribou, arctic foxes, and snowy owls become greatly reduced, as they depend on the tundra environment for their habitat (United States Environmental Protection Agency, 2017). Another comm on example of this negative effect is the shift in habitat for the polar bear. The polar bear depends on sea ice for its habitat, as well as its hunting grounds, where it uses holes in the ice to hunt for seals. As the global temperature increases, the mount of sea ice coverage decreases, which reduces the ability for the polar bear to access its traditional food supply. The loss of habitat is dramatic for the polar bear, as it cannot simply move farther north as other species can, since it already lives in the northernmost area of the planet. For this reason, the polar bear is an endangered species due to the continued effects of global climate change. The topic of global sea level rise has been a part of global climate change research for some time, but recent findings show that the change is accelerating rather than increasing at a constant rate. The new study is based on 25 years of NASA and European satellite data and shows that the acceleration has the potential to double the sea level rise by 2100 that had once been projected based on a steady increase in sea level. If the rate continues to increase at its current pace, sea level could be 65 cm higher than it is today by the year 2100 (Weeman, 2018). The rise of sea surface levels are due to increases in global temperature, which results in two types of changes. First, the increasing temperature melts the ice sheets, releasing more water into the ocean. Second, the addition of this warmer water and the overall increase in ocean temperature causes thermal expansion (due to hydrogen bonding) of the ocean waters, meaning the volume of the water increases as a direct effect of th e temperature increase. Around the world, even small increases in sea level can cause catastrophic changes in habitats, for humans and wildlife alike. Coastal populations, especially those that exist closer to current sea-level will lose use of the land, including homes, businesses and other infrastructure in the area. Populations will need to move further inland, further stressing the already dense human population, particularly in countries like the U.S. and China. Changes in sea level will also affect land dwelling animals and vegetation, which can cause disruptions to coastal ecosystems and eventually inland ecosystems, as species that are able to migrate inland encroach on other established ecosystems. Global climate change also has potential health effects on humans. According to the Executive Summary of the Impacts of Climate Change on Human Health in the United States, climate change affects food and water sources, the air that people breathe, the weather, and interactions with both the natural and built environments. Increased temperatures can lead to locally extreme heat events, increasing the frequency of heat-related illnesses and deaths, especially for the elderly, young children, and those with chronic illnesses. Weather patterns and sea level rise will disrupt infrastructure and cause coast flooding, which will negatively impact access to essential services like power, clean water, and emergency servicesà (Crimmins, 2016). The changes in seasonal weather patterns will also affect food and water quality as well as changes in infectious agents, which will increase the likelihood of food, water and vector-borne diseases, such as Lyme disease (Crimmins, 2016).à Although there is an abundance of evidence supporting the issue of global climate change, naysayers still exist, using disinformation strategies to confuse the public and delay action on remediation efforts. Many of these large organizations receive most of their funding from large oil companies, whose businesses will not benefit from legislative action for remediating climate change. However, the currently most noteworthy stakeholder group that opposes climate change is the Trump administration. It is difficult to summarize the major stances against climate change of this administration, since most of the arguments have long since been negated by many scientific reports. For example, Scott Pruitt, the current EPA administrator questions ââ¬Å"whether we can measure ââ¬Ëwith precisionââ¬â¢ the role of humans on the climate,â⬠and he proposed, based on this, that humans may not be the major driver of global warming (Mooney, 2017). As a reflection of this stance, the curren t administration has revisited the fuel efficiency standards previously put in place by the Obama administration, a beginning step towards reversing the effort to lower carbon emissions. Based on the unsubstantiated argument that climate change is not definitively caused by humans, the Trump administration has moved toward lowering air pollution regulation standards, defunding major climate research projects, omitting climate change as a national security threat, and even taken down the climate change pages of the Environmental Protection Agency website (Greshko, 2018). The list of stakeholders and organizations that back the issue of climate change is long and substantial. One such organization is the U.S. Global Change Research Program. In the 2017 Executive Summary, it is stated that the global average surface air temperature has increased 1.8à °F over the last 115 years, which is the warmest in the history of modern civilization (Wuebbles, 2017). The report concludes that the dramatic changes are extremely likely to be due to the changes in human activities, based on extensive evidence. The most important point that is made in the executive summary is the positive correlation between the increase in anthropogenic production of greenhouse gas emissions and the many adverse effects on the global climate and the Earth systems, including sea surface temperature, ocean acidification, sea level rise, air pollution, and melting glaciers. The amount of scientific evidence supporting global climate change is substantial and there are many different sources that can be discussed. The most commonly discussed anthropogenic driver of the current changes to the climate is carbon dioxide. Carbon dioxide is a major pollutant produced by various processes in human industry, such as the exhaust from combustion engines in vehicles. Carbon dioxide is a greenhouse gas, meaning that it traps heat that is radiating back from the Earthââ¬â¢s surface, which initially arrived as solar radiation. Due to its ability to increase the average global temperature of the atmosphere, it becomes part of several strong positive feedback loops, which amplify its effect. For example, the increasing temperature of the atmosphere allows more sea ice and snow to melt, reducing the planetââ¬â¢s albedo, or ability to reflect solar radiation, which allows more radiation to be absorbed at the surface, further increasing surface temperature. Melting of this snow and ice can also accelerate the breakdown of organic matter from below the permafrost, releasing more carbon from the long-term cycle into the short-term cycle, which will further contribute to the positive feedback loopà (Schuur, 2015). The relationship between the increase in atmospheric carbon dioxide and surface temperature is strongly correlated, as shown below in the figure from Climate Central: The figure shows the strong positive correlation between the temperature anomaly, which is compared to the temperature baseline from the early industrial time period, and the rising carbon dioxide concentration in parts per million (ppm) (Climate Central, 2017). The next figure from NASA shows the historical trend of carbon dioxide over a much longer time period, as far back as 650,000 years. The figure clearly demonstrates how dramatically the carbon dioxide concentrations have increased since the rise of industry. Although those that are against climate change will point out the clear repeating trend of low and high carbon dioxide concentration, there is only one clear cause for the steep increase that began in the time period of the industrial revolution (Graphic: The relentless rise of carbon dioxide). Climate scientists have obtained accurate records of historical carbon dioxide levels from glacial ice. The air is locked in layers over time, which forms bubbles in the ice. Scientists are able to run tests on these samples to determine the amount of carbon dioxide that was present in the atmosphere in the corresponding time period. They can then compare this level to the temperature determined from proxy data from tree rings and water vapor oxygen ratios in other samples from the time period. One of the possible solutions for mitigating the effects of climate change would require the foregoing of the use of fossil fuels. Since the primary driver of global climate change is the increase in carbon dioxide concentrations in the atmosphere, and the carbon dioxide comes mainly from emissions from fossil fuel usage, the fossil fuel usage is a significant problem. Fossil fuels are also removed from the deep carbon reservoirs, and by removing them for human use, carbon is being rapidly moved from a long-term sequestered cycle to a short to term cycle in the surface and climate system. Eliminating, or even reducing, the use of fossil fuels, particularly in developed countries, comes with significant costs. The leading mode of travel by the average working citizen is their privately owned vehicle, which normally runs on traditional gasoline, a major source of carbon emissions. Many people have a significant daily drive to their workplace. The start-up costs for people in this econo my make it difficult to switch to more eco-friendly options for travel. There are also not yet many incentives to alter their travel habits. The need to switch from fossil fuels is also a risky move for the economy since many of the largest industry leaders are the oil companies. The movement for climate change legislation has been battling against oil companies for a long time since oil companies are believed to provide funding for many political campaigns, thus ensuring that their businesses will continue to flourish. Coal is estimated to provide about half of the electricity in the U.S., and a similar percentage worldwide. If the coal and oil companies were to endure far stricter regulations in order to reduce carbon emissions, there would likely be great risk to the global economy. If fossil fuels were to be used less or not at all, and alternative energy sources were used in their place, it should be possible to cease the increase of carbon dioxide concentrations in the atmosph ere and allow the global climate to eventually recover to a more normal state. Reducing the carbon dioxide concentration in the atmosphere will positively affect many aspects of the climate. Global average temperatures will eventually return to more normal ranges, the sea level should no longer continue to rise, and air pollution will be reduced, saving people from heat related death and sickness, as well as food and water-borne diseases. Another benefit to decreasing the carbon dioxide concentration will allow for the acidification of the ocean waters to slow and possible decrease. Another key solution for mitigating climate change would be to reduce the deforestation of the planet. Trees and other vegetation are an important piece of the carbon cycle. When vegetation dies, it eventually becomes part of the long-term carbon cycle, which means that it will eventually be turned back into rock and sequestered in the Earth, but this process occurs over a much longer time scale. When humans purposely destroy forests for various reasons, a substantial amount of carbon is released into the system as biological carbon, into the ground, the ocean and the atmosphere. Not only does deforestation increase the amount of carbon dioxide in the atmosphere, which increases global surface temperature, it also decreases the Earthââ¬â¢s albedo. Tree cover has a higher albedo value than agricultured land and black pavement, so when they are torn down, the ability of the Earthââ¬â¢s surface to reflect radiation back to space is decreased. This results in more heat becoming abs orbed at the surface, which causes more melting of ice and snow, further amplifying the warming and melting effects. The cost of reducing the amount of deforestation means losses for the agricultural industry, since this is one of the primary reasons lands are cleared. Reducing deforestation means that farmers will have less land to use for growing crops and less pasture space for grazing animals. Agriculture is a major source of sustainable food for many countries and the need for land in the industry is growing. It could also mean losses for the construction industry, as new regulations would prevent unnecessary clearing of land for new building projects. There are some risks to reducing deforestation. Deforestation helps to reduce likelihood of fast-spreading forest fires. Areas that are prone to forest fires often perform preemptive cutting. Forest fires negatively affect the atmosphere, as they rapidly inject carbon dioxide into the air. If certain areas were not permitted to c ut trees as they need to, it could put them at risk for more forest fires, which could be more dangerous in the short-term. However, reducing deforestation would be beneficial because it would no longer decrease the planetââ¬â¢s albedo and would reduce the amount of extra carbon dioxide being injected into the atmosphere. The best recommendation for mitigating, and hopefully reversing, the effects of global climate change would be to cease the use of fossil fuels. Since the anthropogenic removal of carbon from the Earth for fossil fuels has been determined to be the source of the leading cause of global climate change, it would make sense for it to be the most important solution for reversing the adverse effects that it has had on the planet. Humans removing various carbon-based fuels from their long-term sequestration in the Earth has led to an over-dependence on its various forms of energy production. The burning of these fuels produces the carbon dioxide that has been building up in the atmosphere, which is the leading greenhouse gas that traps heat in the atmosphere. Along with the direct effect that carbon dioxide has on atmospheric temperature, its increased concentration in the air allows for more to be dissolved and temporarily sequestered in the oceans, which causes ocean acidification. Ocean acidification has negative effects on coral reefs and ocean life. As the temperature of the ocean increases alongside the atmosphere, the ocean also holds less carbon dioxide, lessening the oceanââ¬â¢s ability to assist in cooling the surface temperature. The addition of carbon dioxide to the atmosphere via the burning of fossil fuels moves the carbon to the short-term carbon cycle. It takes much longer for carbon to move back into a long-term cycle once it has been removed because it takes several hundreds or thousands of years for the carbon material to decay and compact into the rock sediment once again. Although there are other greenhouse gases and other long-term factors contributing to global climate change, the use of carbon-based fossil fuels is the most significant, as the changes to the atmosphere began at the same point in history when fossil fuels drove the industrial revolution. The most logical recommendation for reversing the negative effects which have been worse ning since this time period is to reverse the most significant shift in the use of fossil fuels for energy that began over 250 years ago. Works Cited Climate Central. (2017, April 19). Rising Global Temperatures and CO2. Retrieved from Climate Central: http://www.climatecentral.org/gallery/graphics/co2-and-rising-global-temperatures Crimmins, A. J. (2016). Executive Summary. Impacts of Climate Change on Human Health in the United States: A Scientific Assessment. Washington, D.C.: U.S. Global Change Research Program. Retrieved from U.S. Global Change Research Program, Washington, Graphic: The relentless rise of carbon dioxide. (n.d.). Retrieved from NASA: Global Climate Change: https://climate.nasa.gov/climate_resources/24/graphic-the-relentless-rise-of-carbon-dioxide/ Greshko, M. P. (2018, Apri 6). A Running List of How Trump Is Changing the Environment. National Geographic. Mooney, C. (2017, December 29). What position does the Trump administration take on climate change? All of them. The Washington Post. Schuur, E. A. (2015). Climate change and the permafrost carbon feedback. Nature, 171-179. United States Environmental Protection Agency. (2017, January 19). Climate Impacts on Ecosystems. Retrieved from Environmental Protection Agency: 19 January 2017 Snapshot: https://19january2017snapshot.epa.gov/climate-impacts/climate-impacts-ecosystems_.html Weeman, K. L. (2018, February 13). New study finds sea level rise accelerating. Retrieved from NASA: Global Climate Change: https://climate.nasa.gov/news/2680/new-study-finds-sea-level-rise-accelerating/ Wuebbles, D. D. (2017). Executive summary. In: Climate Science Special Report: Fourth National Climate Assessment, Volume I. Washington, DC, USA: U.S. Global Change Research Program.
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