Introduction
Global warming refers to the “increase in the average temperature of the earth’s atmosphere and oceans” (Maslin, 2007, p. 5). Scientists began to detect significant increases in global temperature from the beginning of the 19th century. The temperature of the earth’s surface increased by, approximately, 0.50 Celsius in the 20th century (Maslin, 2007, p. 7).
Most scientists believe that global warming occurs due to human actions that lead to increased emission of greenhouse gases into the atmosphere. Greenhouse gases are the byproducts of human activities such as deforestation and using fossil fuels in production and transportation. Some scientists believe that global warming occurs due to natural events such as volcanic activities.
Global warming is a threat to the sustainability of the world due to its adverse effects on the human population, as well as, plants and animals. This paper focuses on global warming by answering two questions, which are as follows. First, is global warming due to human actions? Second, can the human race take actions to stop global warming? Furthermore, the impact of global warming and the measures that can help to reduce it will be discussed.
Supporting Arguments
Human beings mainly contribute to global warming through their activities, which lead to the production of greenhouse gases. The main types of greenhouse gases include water vapor, ozone, carbon dioxide, and methane. These gases cause global warming through a process referred to as the greenhouse effect. Generally, this effect refers to the “process in which the lower atmosphere and the surface of the earth become warm due to the absorption and emission of infrared radiation by gases in the atmosphere” (Archer, 2011, p. 13). Water vapor and carbon dioxide are the main causes of greenhouse effect.
Industrial production and technological advancements are the main causes of the increase of greenhouse gases in the atmosphere. In the last three centuries, the amount of carbon dioxide in the atmosphere increased by 36%, whereas that of methane increased by 148% (Archer, 2011, p. 46).
In the last three decades, the increase in the emission of greenhouse gases was primarily driven by rapid expansion of the human population and the world gross domestic product. These occurrences were characterized by activities such as deforestation, as well as, production of various goods and services through technologies that cause greenhouse gas emissions.
The use of fossil fuels alone contributes as much as 30 billion tons of carbon dioxide annually. Research indicates that the concentration of carbon dioxide before the industrial revolution was less than 280 ppmv, whereas the current level exceeds 380 ppmv. Currently, the increase in carbon dioxide concentration is rising at a rate of 1.8 ppmv per year (Archer, 2011, p. 56).
Consequently, the amount of carbon dioxide in the atmosphere is expected to exceed 500 ppmv by 2050. These trends indicate that human beings are responsible for the increased concentration of greenhouse gases in the atmosphere. Consequently, global warming is a direct product of human actions.
Research reveals that solar activity and reflectivity have very little effects on global warming. Studies on solar activity indicate that the sun’s output has remained the same since 1975 (Maslin, 2007, p. 24). In this regard, an increase in solar energy is not the main cause of the sharp increase in global temperature that has been witnessed in the last three decades.
This argument is reinforced by the fact that climatic models fail to provide evidence that links the rapid warming of the earth’s surface with variations in solar energy and volcanic activity. The difference in the level of temperature in different layers of the atmosphere also suggests that the sun and volcanic activities have had little contributions to global warming.
Concisely, greenhouse gases cause an increase in temperature in the lower atmosphere and a reduction in temperature in the upper atmosphere. Thus, the sun can only be responsible for the warming if temperatures increased in both the upper and the lower layers of the atmosphere. This intuition indicates that global warming is the result of human activities rather than solar or volcanic activities.
Finally, reflectivity causes cooling rather than warming effects on the earth’s surface. Human activities such as using fossil fuels in production cause atmospheric pollution through particulates that have a cooling effect. This effect often reduces the increase in temperature that is caused by greenhouse gases. This explains the reduction in global temperature that was witnessed from 1945 to 1975 (Archer, 2011, p. 69).
This period was characterized by a sharp increase in particulates in the atmosphere. However, rapid increase in global temperature continued after 1975. During this period, developed countries focused on cleaning up their particulate pollution, while increasing greenhouse gas emissions. This shows that human activities that lead to the production of greenhouse gases are the main cause of global warming.
Opposing Arguments
Some scientists believe that human activities have little effect on climate change. Consequently, global warming cannot be attributed to human actions. The arguments that support this premise are as follows. First, the human population is responsible for the emission of a very small percentage of greenhouse gases compared to other sources of these gases.
In particular, the oceans produce over 60% of the greenhouse gases, whereas other living organisms on land produce 30% of the gases (Archer, 2011, p. 86). Human activities such as using fossil fuels in factories produce only 3% of the greenhouse gases that cause global warming. These statistics indicate that non-human activities emit the largest amount of greenhouse gases into the atmosphere. In this regard, human activities have little or no effect in the process of global warming.
Second, scientists are yet to provide empirical evidence to support the claim that carbon dioxide is a major cause of global warming. The theory that links carbon dioxide concentration in the atmosphere to global warming is based on the correlation that has been observed between the two. In the last five hundred years, scientists have observed a strong correlation between carbon dioxide concentration and changes in global temperature.
However, increases in global temperatures have always preceded the rise in carbon dioxide concentration (Archer, 2011, p. 91). In this regard, the cause and effect relationship between the two indicates that an increase in global temperature leads to a rise in carbon dioxide concentration. This means that an increase in carbon dioxide concentration does not cause an increase in global temperature. Thus, human activities that lead to the production of carbon dioxide do not cause global warming.
Third, some scientists believe that the sun plays an important role in the process of global warming. Their argument is based on the observed warming that is currently happening in other planets (Archer, 2011, p. 112). For example, ice caps are melting in Mars, whereas Jupiter continues to experience storms that are more violent than before. Some scientists argue that global warming started naturally through life processes such as breathing, which lead to the emission of greenhouse gases such as carbon dioxide. In this regard, global warming is essentially a natural process. However, human activities are likely to contribute to its escalation.
Finally, the significant variations in cooling and warming trends before 1940 cannot be explained by human activities that lead to greenhouse gas emissions. During this period, anthropogenic factors did not have significant effects on climate. Most of the greenhouse gases were emitted into the atmosphere after 1940 (Maslin, 2007, p. 65). Thus, anthropogenic greenhouse gases did not contribute to the warming that occurred before 1940. Hence, human activities that led to increased emission of greenhouse gases after 1940 are responsible for a very small percentage of the warming that has been experienced since the 20th century.
The Impact of Global Warming
Global warming is a threat to the sustainability of the world due to its adverse effects on the climate and the ecosystems that support various plant and animal species. The effects of global warming include the following. First, natural disasters such as draughts and floods usually occur due to climatic changes that have been occasioned by global warming. A rapid increase in temperature usually accelerates evaporation (Uddin & Rahman, 2011, pp. 372-389). The evaporated water often forms clouds, which eventually falls back to the earth’s surface as rainfall or snow.
However, the distribution of rainfall across the earth’s surface is often uneven. Rapid evaporation in dry areas where plants and animals depend on water bodies such as rivers is likely to cause severe draughts. On the contrary, a large amount of water is likely to evaporate in wet areas, thereby causing high precipitation and floods. Floods and draughts are undesirable climatic conditions because they lead to the destruction of plants and animals, as well as, their habitats. Similarly, draughts and floods threaten the survival of the human population by limiting their capacity to produce food.
Second, global warming is likely to cause a rise in the sea level. This is because it is responsible for the large amounts of ice caps that are melting at the North Pole and South Pole. The melting of the ice leads to the production of large amounts of water, which flow into oceans. The sea level is likely to increase as more water flows into the ocean.
The problem of rising sea level is that it will submerge low-lying coastal areas and islands. At least “two thirds of the human population lives within 150 kilometers of the coastline” (Archer, 2011, p. 142). Consequently, several of homes and millions of lives will be destroyed if coastal areas are submerged. Additionally, thousands of animal and plant species will be destroyed. Moving the coastal population inland will result into overcrowding due to land shortage.
Third, global warming is likely to cause extreme weather. In particular, it can lead to the occurrence of high intensity winds, rains, and storms. A significant change in the climate will lead to the death of animal and plant species that cannot adapt to the changes (Maslin, 2007, p. 55). There is strong evidence that the climate will be very different in future.
The evidence includes reports of winds and storms whose velocity is significantly higher than normal rates. Extreme weather conditions such as high velocity winds often destroy plants, houses, and factories among others, thereby threatening the sustainability of the world. Furthermore, climatic changes usually cause an increase in the prevalence of diseases such as malaria, diarrhea, and dengue fever.
Controlling Global Warming
Global warming can be controlled by taking the following measures. First, it can be minimized by reducing the human activities that generate greenhouse gases. This involves using energy efficient technologies in order to reduce the emission of greenhouse gases such as carbon dioxide (Jacobson, 2009, pp. 42-78). For example, cars that are properly maintained consume less fuel.
Thus, they produce less carbon dioxide, thereby reducing global warming. Both developed and developing countries should focus on replacing the use of fossil fuels with renewable energy sources. Research indicates that renewable sources of energy such as wind power emit very little or no amount of greenhouse gases. Thus, using them in industrial production and transportation will significantly reduce global warming. Countries can also reduce the emission of greenhouse gases by using mass transportation systems such as electric trains instead of gasoline-powered personal cars.
Trees normally use carbon dioxide for photosynthesis. Thus, planting more forests or restocking existing ones will help in reducing the amount of carbon dioxide concentration in the atmosphere. The challenge to this strategy is that there might not be enough land to plant more trees in some parts of the world. Governments should also use environmental protection policies to control greenhouse gas emissions. This involves setting emission standards and ensuring that all stakeholders adhere to them.
Second, adaptation can be used as a response to global warming. It involves reducing the vulnerability of the human population to the adverse effects of climatic changes. Adaptation is necessary because global warming is already causing climatic changes whose effects are likely to last for several years (Jacobson, 2009, pp. 42-78).
The problem associated with adaptation is that it requires a lot of financial resources and changes in human being’s lifestyles. Additionally, the adaptive capacity of the human population is limited. For example, human beings cannot survive at temperatures that exceed 35 degrees Celsius. Finally, global warming can be reduced through geo-engineering. This involves modifying the climate through programs such as “solar radiation management and carbon dioxide removal” (Archer, 2011, p. 184).
Conclusion
Global warming is associated with a rapid increase in global temperature over time (Maslin, 2007, p. 5). Traditionally, it has been attributed to human activities such as using fossil fuels and deforestation. These activities produce greenhouse gases such as carbon dioxide, thereby causing global warming. However, recent studies indicate that human activities have made insignificant contribution to global warming.
These studies reveal that oceans and non-human activities produce over 90% of greenhouse gases. Therefore, they are the main causes of global warming. The effects of global warming include extreme weather, rising sea level, as well as, reduction in food production and increased prevalence of diseases. Due to these effects, global warming should be controlled by using energy efficient technologies and clean energy, as well as, adaptation.
References
Archer, D. (2011). Global Warming: Understanding the Forecast. New York: John Wiley and Sons.
Jacobson, M. (2009). Effects of Bio-Fuels Verses other New Vehicle Technologies on Air Pollution, Global Warming, Land Use and Water. International Journal of Biotechnology, 11(2) , 42-78.
Maslin, M. (2007). Global Warming. New York: McGraw-Hill.
Uddin, M., & Rahman, A. (2011). Techniques to Improvement in Green Data Centres to Achieve Energy Efficiency and Reduce Global Warming Effects. International Journal of Global Warming, 3(4) , 372-389.