Table of Contents
Background on Anthropogenic Global Warming
A precise perception regarding the extent of scientific agreement plays a crucial role in determining the degree of public support towards climate change policy. In addition, communication of this scientific agreement also enhances the public acceptance that global warming is a reality. Regardless of various indicators suggesting scientific agreement, there is a widespread perception among members of the public that client scientists do not agree with respect to the root cause of global warming. Surveys performed by climate scientists show a strong agreement of about 97-98 percent that Anthropogenic Global Warming (AGW) is a fundamental factor contributing to global warming (Cook, Nuccitelli, and Green 2). For instance, when analyzing peer-reviewed published papers on climate, one can notice a steady increase in agreement that AGW was the leading cause of global warming, especially during the period 1996-2009. In addition, the Intergovernmental Panel on Climate Change (IPCC) has consistently emphasized the definitive role that AGW plays with respect to climate change. Regardless of these several indicators suggesting scientific agreement, there is still a widespread perception among the United States citizens that the scientific community is yet to reach an agreement regarding the fundamental cause of climate change. During the period 1997-2007, opinion polls in the United States suggested that about 60 percent of the United States citizens were of the belief that there was a considerable disagreement among climate experts on whether global warming is actually happening (Cook, Nuccitelli, and Green 3). In addition, 57 percent of the US citizens were not aware or disagreed that a consensus existed among scientists that global warming could be primarily attributed to human activity (American Geophysical Union 5). The lack of agreement among members of the public makes it difficult to convince people that AGW actually exists. As a result, strategies to deal with AGW are likely to be met with the objection and may be ineffective in combating global warming.
AGW denotes the climate change attributed to the emission of greenhouse gases because of human activity. Through studying polar ice cores, climate experts and scientists are fully convinced that human activity has played a pivotal role in increasing the quantity of greenhouse gases in the earth’s atmosphere, which has increased significantly in the course of the last few centuries. A 2007 report published by the IPCC revealed that several forms of evidence suggested that the significant increase in greenhouse gases following the industrial era were not attributed to natural causes (American Geophysical Union 6). Carbon dioxide is the most intoxicating greenhouse gas followed by methane and then nitrous oxide. It is not surprising that the increasing amount of these gases in the Earth’s atmosphere is causing AGW. Furthermore, the highest quantities of these gases were recorded for the first time over a duration of 650,000 years. The report by the IPCC revealed that during the previous 8 millennia, and just prior to the commencement of the industrial age during the 1750s, the concentration of carbon dioxide in the Earth’s atmosphere increased by just 20 ppm - parts per million (Intergovernmental Panel on Climate Change para. 5). In the year 1750, the amount of carbon dioxide in the Earth’s atmosphere was reported to be 280 ppm. However, in 2007, the concentration of carbon dioxide was 379 ppm, an increase of about 100 parts per million in just 250 years (Cook, Nuccitelli, and Green 5). At the end of the latest ice age, an 80 ppm increase in carbon dioxide concentration was documented (Intergovernmental Panel on Climate Change para. 5). This increase took about 5000 years, and the concentration value exceeding the present value occurred in the past several million years.
From 1750 onwards, it has been established that about 66 percent of AGW carbon dioxide emissions are linked to the burning of fossil fuel (petroleum and coal). Furthermore, 33 percent of AGW is linked to changes in land use, especially agricultural and deforestation (American Geophysical Union 5). An estimated 45 percent of carbon dioxide has been trapped in the Earth’s atmosphere, whereas oceans have taken up roughly 30 percent (American Geophysical Union 4). Plants and trees have taken up the remainder. In addition, it has been established that about 50 percent of carbon dioxide emissions to the atmosphere require approximately 30 years to be removed. An additional 30 percent requires a few centuries to be removed, whereas the remainder (20 percent) stays in the atmosphere for several thousand years (Intergovernmental Panel on Climate Change para. 5).
Recent decades have witnessed a steady increase in carbon emissions in the Earth’s atmosphere. For instance, during the 1990s, the yearly global fossil emission was estimated to be 64 gigatonnes of carbon per year. During the years 2000-2005, it had increased to about 7.2 gigatonnes. It is imperative to note that the use of fossil energy is not the only human activity that contributes to AGW. Land use has been established to contribute approximately1.6 gigatonnes of carbon per year (Intergovernmental Panel on Climate Change para. 4). Apart from the increasing use of coal following the Industrial Revolution, the use of petroleum, another fossil fuel, increased significantly during the post-industrial era. At the start of the twentieth century, the yearly global oil output was approximately 150 million oil barrels. Presently, this annual amount of oil can be extracted within two days globally (Cook, Nuccitelli, and Green 5).
Climate models have projected an increase in global temperatures, with the intensity of global warming depending on the amount of emissions in the atmosphere. Simply stated, higher amounts of emissions in the atmosphere will result in larger global warming and increased risks to ecosystems and society.
Potential Threats of AGW
Impacts of AGW pose significant threats to society. They can be both social and environmental. Most of the threats posed by AGW have already been witnessed, such as reduced agricultural productivity and glacier threat. AGW has physical impacts such as the increasing land and ocean temperature as well as the increase in sea levels. Activities performed by humans have been primarily linked to the warming of the Earth, especially through the use of fossil energy. AGW has been established to have the potential of resulting in large-scale changes in physical systems that may be abrupt and irreversible. A case in point is the ice sheets melting, which has led to an increase in the sea levels (American Geophysical Union 5).
AGW also poses a threat to sectors and systems. One of the sectors likely to witness the profound impact of AGW is the health sector. AGW has resulted in an increase in heat-related deaths and has changed the distribution of a number of infectious diseases. In addition, AGW has an impact on the health status of people globally through injury and diseases associated with extreme weather. Furthermore, it increases the burden placed on diarrheal infections the prevalence of cardio-respiratory infections. Finally, AGW changes the spatial distribution of a number of contagious illnesses. Essentially, AGW has resulted in severe and likely long-lasting alterations to the Earth’s ecological, biological, geological, and social systems. Low-income communities are the most vulnerable to the threats posed by AGW because of their increased susceptibility to environmental variables that affect wealth and health as well as their reduced capacity to cope with climate chhange (Intergovernmental Panel on Climate Change 2).
AGW also threatens national security. In this respect, the increasing temperatures on the Earth, rising sea levels, unstable patterns of rainfall, and harsh weather conditions are likely to magnify the challenges associated with global conflict, poverty, starvation, and volatility. Such events are likely to result in disputes, epidemic diseases, and food and water shortages among others. Essentially, AGW is considered a threat to national security because of its threat multiplier effect in the sense that it can aggravate most of the challenges facing the world today ranging from terrorism and infectious diseases. These impacts have already started manifesting themselves. In addition, climate change will have an impact on the US military, including the manner in which the missions of the military will be executed (Chuck para. 5). The US military can be required to offer backing to the civil agencies, offering humanitarian help as well as disaster relief when the natural catastrophes increase in terms of rate of recurrence and intensity. The military establishments in coastal regions of the US are susceptible to the increasing sea levels and flooding whereas wildfires and drought pose a threat to the training activities of the US military. In addition, these harsh conditions have the potential of disrupting the supply chain of the US military together with the challenge of making sure that critical equipment is functioning amidst the extreme conditions. There is no doubt that weather always has an effect on military operations; therefore, a change in climate is likely to result in constraints or changes in the manner in which military operations are executed (Chuck para. 5).
Policy Advice on Combating AGW
Combating the threats posed by AGW requires the adoption of actions that can limit the scale and rate of global warming. They include the use of climate change mitigation, which focuses on reducing human-related greenhouse gas emissions. Some of the mitigation efforts used in countering the threats of global warming include using alternative sources of energy like nuclear and renewable energy sources and expansion of areas covered by forests in order to help lessen the concentration of carbon dioxide in the atmosphere (Intergovernmental Panel on Climate Change para. 1). Another climate change policy is an adaptation, which has the main goal of lessening the susceptibility of biological and social systems to the existing climate change; therefore, counterbalancing the impacts associated with AGW. Even in a scenario with stable carbon emissions, climate change and its respective impacts are likely to last for several years. As a result, adaptation is likely to be a requirement for managing AGW effects. The focus of adaptation is in local planning; improving adaptive capacity; agricultural production measures such as increased irrigation, storage of rainwater, and use of drought-tolerant crops; and migration (American Geophysical Union 4).
A number of actions can be undertaken to combat the threats posed by AGW to society and national security. These measures should focus on significant reductions of the emissions with the main aim of reducing the scale of climate change and preparing for already inevitable changes. The scientific community has the primary responsibility for ensuring there is an improved overall understanding among the public in regards to climate change and its impacts. These improvements can be achieved by performing the research required to have an understanding of global warming, collaborating with stakeholders in order to have an understanding of pertinent information, communicate this information in an accurate and clear way to the public and decision-makers.