How Global Warming is Not Caused by Humans?

Introduction

Global climate change is a topic that has received a lot of debate over the past few years. Scientists define global warming as the increase in average temperature that gradually warms the earth's atmosphere. In the last century, global warming is a phenomenon that has been on the rise. According to EL-Sharkawy (2014), the levels of increase in global warming are alarming. The recent changes in the global environment, for instance, a change in weather patterns can be attributed to the changes in global warming levels. El-Sharkawy, (2014) the increased emission of greenhouse gasses has resulted in increased global temperatures. A study conducted by the Intergovernmental Panel on Climate Change (IPCC) support the finding by El-Sharkawy (2014) in that increased concentration of greenhouse gases on the atmosphere has resulted in increased global average temperature. Scientists state that the increase in the global temperatures is likely to cause the ice age which would wipe out the entire world (Singer, 2008). Scientists at the IPCC have shown that the 21st century is facing the threat of increased reduction of snow cover and glaciers (Singer, 2008). This is likely to result from the increased global temperatures which are being experienced globally. This is expected to reduce the availability of water; hydropower potential as well as changes in seasonality of flows in areas supplied by melt water from major mountain ranges whereby over one-sixth of the world population inhabits.

There are various causes of global warming according to scientists and researchers in the field. The most common associated cause of climate change is human activities. The release of excessive greenhouse gases by a human is viewed by many as the major cause of global change (Singer, 2008). On the other hand, others argue that climate change is caused by natural causes and thus human's activities have little effect on climate change. This paper seeks to investigate the arguments raised by those who argue that natural causes cause global warming as opposed to human causes. The essay will present arguments to show that global warming is indeed caused by humans and invalidate the arguments introduced by those who argue that humans should not be blamed for global warming.

First, those who argue that global warming is as a result of natural causes argue that scientists cannot prove that the current warming is not natural. Proponents of this argument state that climate scientists cannot provide proof that the current global warming being experienced is not due to natural processes as opposed to human activities. Therefore, the claim that human interference is the main cause of global warming should be argued from a scientific point of view. In a complex system like climate, it is virtually impossible to prove a negative phenomenon of course. It is almost impossible to certainly prove that natural processes are not causing the current global warming. Instead what scientists do is eliminate every possible natural explanation that can be posited.

According to thermodynamics, the warming of the Earth's lower atmosphere must result from one or more processes that supply excess heat to the lower atmosphere (Simon & Smithsonian Institution, 2010). Apart from greenhouse effect other factors that are likely to result to increase in warming of the Earth's lower atmosphere include; increased absorption of heat from the sun due to a change in the Earth's planetary reflectivity or "albedo", increased output from the sun and lastly an internal variation in the climate system that transfers heat from one part of the Earth to the atmosphere (Simon & Smithsonian Institution, 2010). However, direct observations indicate that none of those mentioned earlier factors explain the observed warming over the past decades. The argument that increased output from the sun has resulted in increased lower atmosphere warming is incorrect. This is so because there has been no appreciable change in solar output is solar output over the past decade. The factor of Earth's reflectivity is also untrue. Satellite data shows that Earth's reflectivity increased in the 30s, 710s, and 80s but has since decreased modestly since (Milfront, 2010).

On the other hand, the argument that internal variation is also invalid. Atmosphere warming on decade time-scales could only have been caused by internal heat from the ocean. However, scientific data shows that the heat content of the ocean has increased instead of decreased over the past decades (Milfront, 2010). This data indicates that the atmosphere has been the source of heat to the ocean as opposed to the ocean is a reservoir of internal heat that could have caused the atmosphere to warm.

Second, proponents of this argument also argue that carbon dioxide which is a major cause of global warming does not come from human activities. They argue that carbon dioxide ha natural sources and thus not as a result of human activity. For instance, animals exhale carbon dioxide which is then absorbed by the plants. Therefore nature itself has a manner in while the little carbon dioxide that comes from humans is utilized and thus the argument that humans are a source of global warming through the addition of carbon dioxide in the atmosphere is vague.

However, facts from scientific studies have shown that the natural environment is a self-sustaining ecology whereby, natural processes emit large amounts of carbon dioxide into the atmosphere and also remove the same through natural processes. This happens at nearly identical rates, and thus the argument that global warming is caused by natural emission of large quantities of carbon dioxide is untrue. This natural emission and absorption of carbon dioxide balance are responsible for maintaining the concentration of carbon dioxide at a stable level (Heos, 2015). Considering the period before the industrial revolution, results from various studies show that the levels of carbon dioxide remained stable for thousands of years. On the other hand, after the industrial revolution, the amounts of carbon dioxide emitted to the atmosphere have increased significantly. Researchers state that the isotonic composition of the carbon in the atmospheric carbon dioxide provides a unique fingerprint. This fingerprint can be used to confirm that the carbon dioxide accumulating in the atmosphere is as a result of emission from burning of fossils fuels. This includes fuels such as coal and petroleum products. For example, industries have since the industrial revolution utilized coal energy as a source of power (Peters, 2012). Coal emits high amounts of carbon dioxide to the atmosphere. Other fossil fuels such as petroleum products are used as a power source in industries and to run automobiles. This has resulted in increased emission of carbon dioxide gas to the atmosphere (Heos, 2015). As the quantity of greenhouse gas level will increase within the atmosphere, heat is treed within the atmosphere and causes warming of the world. Moreover, coal-burning of power plants conjointly will increase the carbon level within the atmosphere. 'Burning coal produces regarding nine billion tons of greenhouse gas annually that is discharged to the atmosphere, and regarding seventieth of this can be being generated from power plants' (Peters, 2012).

Additionally, factories emit additional smoke and harmful gases like a greenhouse gas, methane, and oxide. These gases don't solely increase the temperature of the setting; however, causes damage to humans and animals. It, therefore, becomes impossible for the natural processes to remove the large quantities of carbon dioxide which in turn results to large amounts of the gas accumulating in the atmosphere. This, in turn, results in global warming, and thus the argument that human activities are responsible for increased amounts of carbon dioxide in the atmosphere is true and supported by facts (Peters, 2012).

Thirdly, others argue that no one knows why the climate varies. The global climate over the years has experienced fluctuations over the Earth's history. Those who argue that human beings have no control over global warming, state that the fluctuations which are as a result of internal variability or other unknown reasons in the climate system. Therefore, they argue that since we know very little about the climate system, it is wrong to attribute the present global warming to any specific cause let alone human activity.

However, considering the scientific fact, scientists have reasonable qualitative explanations for most of the significant variations in climate over geological time. According to scientific knowledge, certain climatic variations can be attributed to specific processes, not to unknown internal oscillations (Miller, 2013). Hays et al. (1976) argue that many of the major climatic changes which have been experienced in earth can be linked to the changes in the Earth's orbit around the sun. Other studies show that specific events can be linked to being a direct cause to the climate changes. For example, the assembly or breakup of supercontinents or the impact of a comet or meteorite on the surface of the Earth can be attributed to climatic changes as these events causes' major changes in the atmospheric greenhouse gases concentration (Callery, 2008). Over the past millennium, scientists have successfully attributed the major temperature fluctuations quantitatively to changes in volcanic eruptions, solar activity, particulate pollution, and human-produced greenhouse gases. The results indicate that through natural processes are responsible for climatic fluctuations, the effects are minimal and cannot be attributed to global warming currently occurring (Miller, 2013). On the contrary, scientists have proven beyond reasonable doubt that human activities have resulted in increases in greenhouse gases concentration in the atmosphere, which is a major cause of global warming.

Fourth, the argument that the Medieval Warm Period (MWP) has also been used to disprove humans as the cause of global warming. Proponents of this argument state that the current warming is analogs to the MWP. This is so because the MWP was a natural event. Therefore the current global warming is also likely to be a natural event.

Applying the Medieval Warm Period argument to argue that global warming is caused by natural processes is not only vague but incorrect scientifically. The Medieval Warm Period refers to a relatively warm period which occurred in between the 10th and the 14th century (Simon & Smithsonian Institution, 2010). This period was perceived to have been experienced globally. However, data from recent studies have indicated that the MWP was only experienced in Europe and was not a global phenomenon as initially thought (Morellon et al., 2011). Scientists have over the recent years carried out reconstructions of millennium-scale global temperatures; the results from these experiments have indicated that though the MWP temperatures were high, the average temperatures cannot much the extreme temperatures that we are currently experiencing. Also, the data from these studies show that the MWP was a regional happening as opposed to the current global warming we are experiencing.

Different independent methodologies were introduced by scientist all of which reached to the conclusion that MWP was regional. The most significant reconstruction is that Mann et al. (1998). This reconstruction named "hockey stick" was a graphic reconstruction whose results were discussed in the 2001 Intergovernmental Panel on Climate Change. Other contributors to this scientific evidence include Moberg et al. (2005), McIntyre & McKitrick (2005) and Osborn and Briffa (2006). Studies on melting high altitude glaciers can als...