A long-term alteration in weather conditions is called climate change. There are several indicators that measure climate shift, such as changes in temperature, level of precipitation, wind direction, etc.; moreover, the difference between mediocre and extreme conditions is included. Climate change can be caused by both natural and human-cased processes.
This problem becomes an important reason for apprehension, as it has an influence on every living creature on the planet. The community of scientists believes that the cause of climate changes lies in the global warming. On the other hand, some people claim that the global warming is a myth, though they do not have enough scientific proof to defend their arguments.
Nowadays hardly anyone would argue with the consequences of the change of the climate. The IPCC, which is short for the Intergovernmental Panel on Climate Change, has recently conducted a study, proving that there has been a steady growth in moderate annual temperature over the last few decades. Moreover, these shifts affected the ascending sea levels, which caused a startling increase in floods all over the planet.
Long before humans had a severe impact on the environment, natural processes have resulted in the majority of climate changes. For instance, over the last several million years, the Earth’s climate changed from glacial ages to mildly warm eras. There are several elements of natural processes that could be the reason for climate shifting in the past: volcanic eruptions, the position of the continents, changes in the orbit of the planet, sun magnitude and others.
Volcanic activity and solar changes are the primary natural force to climate changes. According to researchers, “solar output has increased gradually in the industrial era, causing a small positive radiative forcing This is in addition to the cyclic changes in solar radiation that follow an 11-year cycle. Solar energy directly heats the climate system and can also affect the atmospheric abundance of some greenhouse gasses, such as stratospheric ozone” (Lockwood 310).
As for the volcanic activity, eruptions are able to build an adverse effect that lasts up to 3 years due to sulfate aerosol. However, the lower layers of the atmosphere are believed to be free of this element at present, as the last extensive explosion occurred in 1991.
The research has also compared the differences in climate changes between this day and the beginning of the industrial era caused by nature (solar power and volcanoes) and by human activities. The results have shown that human impact on the atmosphere is much bigger and more important for climate shifts in the future than the approximate effect of the natural processes and its changes.
The sun is the central source of energy, on which our climate system relies. Thus, it is only logical to assume that the climate changes could be partially explained by alterations in the energy output of the sun. Furthermore, studies indicate that climate changes in the past directly depended on solar variability (Lean 115). The Little Ice Age could serve as an example of the reduction in solar activity. That was the time when Greenland shifted away from the continent because of the ice (1650-1850), and glaciers made a significant growth in the Alps.
The global warming is the question of the first matter nowadays, and many argue whether the human impact on the climate caused it. Nevertheless, there is certain evidence, according to which solar variabilities cannot be the reason for global warming. First of all, the moderate quantity of solar energy has remained stable since 1750, though the global warming had its first signs much later. Secondly, if the increased activity of the sun caused the global warming, the experts would forecast the warming of all layers of the atmosphere, or the upper ones at least. However, the reality is opposite: the higher parts have been cooling down, whereas the lower layers and the surface have indicated a temperature increase. That could be easily explained by greenhouse gasses, which are a result of human processes, trapping heat near the surface of the planet.
It is known as a fact, that human activity became the primary factor that impacts weather changes. Since the middle of the 20th century, there has been an enormous increase in the greenhouse effect due to human influence. To be precise, the estimated percentage of global warming development over the last 50 years is twice as it was for the whole last century.
As it was mentioned above, global warming effect manifests itself in the escalation of a surface temperature of the planet. Mostly, this phenomenon is a result of burning oil, coal and gas; generally speaking, the fossil fuels. A side product of this process is carbon dioxide, also known as the greenhouse gas, which is released into the atmosphere. Solar and thermic radiation, which is an essential element of a planet’s balance, is affected by this gas and also by aerosols.
According to the research of the United States Global Change Research Program, there are also the following elements, that cause the greenhouse effect:
- Water vapor. The most abundant greenhouse gas, but importantly, it acts as a feedback to the climate. Water vapor increases as the Earth’s atmosphere warms, but so does the possibility of clouds and precipitation, making these some of the most important feedback mechanisms to the greenhouse effect.
- Carbon dioxide (CO2). A minor, but very important component of the atmosphere, carbon dioxide is released through natural processes such as respiration and volcano eruptions and through human activities such as deforestation, land use changes, and burning fossil fuels. Humans have increased atmospheric CO2 concentration by a third since the Industrial Revolution began. This is the most important long-lived forcing of climate change.
- Methane. A hydrocarbon gas produced both from natural sources and human activities, including the decomposition of wastes in landfills, agriculture, and especially the rice cultivation, as well as ruminant digestion and manure management associated with domestic livestock. On a molecule-for-molecule basis, methane is a far more active greenhouse gas than carbon dioxide, but also one which is much less abundant in the atmosphere.
- Nitrous oxide. A powerful greenhouse gas produced by soil cultivation practices, especially the use of commercial and organic fertilizers, fossil fuel combustion, nitric acid production, and biomass burning.
- Chlorofluorocarbons (CFCs). Synthetic compounds entirely of industrial origin used in some applications, but now largely regulated in production and release to the atmosphere by international agreement for their ability to contribute to the destruction of the ozone layer. They are also greenhouse gasses. (“Global Climate Change Impacts” 122)
The majority of the scientific community has come to an agreement that the primary reason for climate change is human-made, and it is the greenhouse effect. Moreover, the scientists have provided a substantial indication that humanity is in charge for the global warming. “Destruction of forests, burning of fossil fuels and environmental pollution are the main reasons behind the greenhouse effect that is currently influencing the climate” (Oreskes 1686)
Short-lived and long-lived climate forcers
As it was mentioned above, carbon dioxide is the leading reason for climate change that was caused by humans. The greenhouse gas is diffused in colossal quantities as a result of burning of fossil fuels. Due to the fact that this gas is highly long-lived, it proceeds to alter the climate system of the planet while evaporating in the atmosphere.
Nevertheless, several industrial processes and agriculture-related activities produce other elements, which are waste products and also appear to have an impact on the climate system. The consequences of releasing these substances in the atmosphere are divided into long-lived and short-lived. Nitrous oxide belongs to the first group and is much like carbon dioxide.
The short-lived elements have the ability to remove themselves quickly from the atmosphere. For that reason, their impact on the climate system is not as disastrous as it is from long-lived substances. However, the quantity of the short-lived elements in the atmosphere is constantly very high; in this case, they are catalysts for a substantial extent of climate forcing. “Some short-term climate forcers have a climate warming effect (‘positive climate forcers’) while others have a cooling effect (‘negative climate forcers’)” (Cesar 38).
Thus begins the complex and intricate question concerning emissions of these substances into the atmosphere. Provided that the short-lived substances are frequently restored by continuing emissions, they would proceed to expand a climate forcing. On the other hand, lowering the atmospheric levels of the elements would lead to the imbalance in the atmosphere.
There are several short-termed climate elements, which are one of the most substantial contributors to the human influence on the global warming after carbon dioxide. This list includes methane, tropospheric ozone and black carbon, which is a product of unfinished ignition of fuels that are based on carbon.
Another category of climate forcers consists of short-termed elements that cause a refrigerant reaction, sulfate aerosols being among them. These substances last in the atmosphere only for several days and wash out with acid rains; thus, their effect on the climate is not as severe as from long-lived greenhouse gasses. Nevertheless, climate forces with cooling effect have a relatively good impact on the atmosphere, as they decrease the warming influence of other elements (Samimi and Zarinabadi 53). In other words, the greenhouse effect would have even more disastrous consequences without sulfate aerosols.
As a conclusion, it is worth saying that even though climate change can be caused by the natural processes of the planet in some measure, humanity carries almost full responsibility for it. The gasses, carbon dioxide, in particular, are absorbing and accumulating heat in the atmosphere, thus keeping the right temperature on the surface of the planet to support life. Nevertheless, burning fossil fuels and other industrial processes are leading to the accumulation of surpluses of the greenhouse gasses, thus making the temperature of the lower levels of the atmosphere higher. Sooner or later, these activities of the humanity will cause multiple problems, which in their turn will outweigh the balance of the climate system of the planet.
Cesar, Herman. Control and Game Models of the Greenhouse Effect: Economics Essays on the Comedy and Tragedy of the Commons. New York City, New York: Springer Publishing, 1994. Print.
“Global Climate Change Impacts in the United States.” Global Change Research Program, Cambridge University Press, 1 (2009): 122. Print.
Lean, Judith. “Cycles and Trends in Solar Irradiance and Climate.” Wiley Interdisciplinary Reviews: Climate Change, 1.1 (2010): 111-122. Print.
Lockwood, Mike. “Solar Change and Climate: an update in the light of the current exceptional solar minimum.” Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 466.2114 (2009): pp. 303-329. Print.
Oreskes, Naomi. “The Scientific Consensus on Climate Change.” Science 3, 306.5702 (2004): p. 1686. Print.
Samimi, Amir and Soroush Zarinabadi. “Reduction of Greenhouse gases emission and effect on environment.” Journal of American Science, 8.8 (2012): p. 49.Print.