Global Warming and Its Causes - Case Study Example

Global Warming and Its Causes In the last two centuries, humans have significantly influenced the environment they live in through their activities, and, unfortunately, this influence appears not to be positive at all. More specifically, they have changes the climate patterns of the planet which result in global warming that has impact on all the living organisms which inhabit the Earth. Not so long ago, some people had doubts concerning the notion of climate change. Today, the fact that it takes place has been finally proved; its causes are still not so clear, though. Opinions are divided: the majority believes that climate change is a human-induced notion, while others think climate change results from natural causes. However, the recent researches and studies show that it is human activity that causes the changes in the Earth’s climate and that natural causes should not be blamed for what is happening now with the planet. In accordance with the Intergovernmental Panel on Climate Change, climate change is defined as a “change in the state of the climate that can be identified (e. g. using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer” (30). Earth’s atmosphere is comprised of different gases, some of which, such as water vapor and carbon dioxide (CO2), take part in the so-called natural greenhouse effect. Because of their activities, humans have altered the natural process causing the increase of these gases in the atmosphere that, as a result, leads to climate change and the rise of the planet’s average temperature in particular, i. e. global warming. The first anthropogenic cause of climate change is proved to be the increase of greenhouse gases in the atmosphere. Scientists started studying climate and atmospheric composition in the nineteenth century, and this examination is taking place these days. The evidence from observations of the surface and atmosphere shows that the amount of greenhouse gases has increased dramatically. Among all the gases in the atmosphere, it is carbon dioxide that appears to be the most important of greenhouse gases. Compared to the data from the eighteenth century, today the atmospheric abundance of carbon dioxide is 40% greater (Hartmann, Tank, and Ristucucci 161). Natural amounts of CO2 varied from 180 to 300 ppm (parts per million), these days the amount of carbon dioxide is about 400 ppm (Environmental Defense Fund). In fact, the same state of things is with the amount of other gases. Accordingly with the data presented in the report on climate change by the IPCC, the amount of such greenhouse gases as nitrous dioxide and methane is at dangerous levels. For example, nitrous dioxide has increased by 20% since the eighteenth century, and methane has increased by 150% since 1750 (Hartmann, Tank, and Ristucucci 161). Overall, the total amount of these gases in the atmosphere has increased by 40 times over the past 800,000 years. The reason for this is human activities: for instance, great amounts of carbon dioxide are emitted through the use of fossil fuels (oil, coal, and gas); nitrous dioxide is emitted because of the use of fossil fuels and through agricultural activities; the same also works for methane. The second human-induced factor that influences the Earth’s climate is clear cutting of forests called deforestation. Even though the increase of the amount of greenhouse gases in the atmosphere is regarded as the main reason of climate change, researchers state land use patterns and, more importantly, changes in them should be taken into consideration as well. The matter is that forests protect the planet from climate change and regulate climate patters due to the fact that trees absorb carbon dioxide. In other words, forests provide “a natural reservoir” for CO2 (WWF). Therefore, when massive deforestation takes place, there is nowhere to keep carbon dioxide, and, consequently, its amount in the Earth’s atmosphere increases. In accordance with World Wildlife Fund, today the bulk of emissions from deforestation is about 19% of global emissions, which is more that emission from the transport sector. The importance of forests for the Earth’s climate is better explained on examples. For instance, the well-known Amazon forests are a natural reservoir for about 90-140 billion tons of CO2; this amount is equal to 9-14 years of global emissions of CO2. Sumatra’s Peat Swamps are also of great importance for the Earth’s climate as they keep more CO2 than any other existing ecosystem (WWF). At the same time, these and many other ecosystems can be ticking time-bombs because their degradation results in the release of millions of tons of carbon dioxide. Despite this, deforestation is continuing taking place, and the statistical data are staggering. Every year 13 million hectares of forests are cut over; this number equals about 36 football fields per minute (WWF). That is why stopping deforestation are very important for keeping carbon dioxide at reasonable amounts. The increase of greenhouse gases and deforestation do not fully explain all trends in climate change. One more significant anthropogenic cause of climate change is the use of aerosols, which are defined as “small particles present in the atmosphere with widely varying size, concentration and chemical composition” (Forster, and Ramaswamy 135). Aerosols reflect and absorb infrared and solar radiation and cause a negative radiative forcing as the change physical and chemical cloud properties, the amount of clouds and the way they are formed in the atmosphere. Apart from that, aerosols are trapping long-wave radiation. It is human activity that have led to the increase of the amount of aerosols in the Earth’s atmosphere. More specifically, aerosols are emitted because of specific agricultural processes and biomass burning. In addition to this, emissions from fossil fuels burning also result in the increase of the amount of aerosols because a part of these emissions are converted to aerosols as a consequence of a range of chemical reactions taking place in the atmosphere. The evidence for climate change is rather convincing. In the last century, global sea level rose more than 6 inches, and in the last decade, the rate doubled. Also, global surface temperature has increased with the 20 years since 1981 being the warmest years ever. As a result, oceans absorb more heat and their waters get warmer as well. In addition to this, ocean acidification have been taking place since the beginning of the Industrial Revolution. Accordingly with NASA, the acidity of oceans has increased by 30% because more carbon dioxide is emitted into the atmosphere. Ice sheets in the Greenland and Antarctic have been losing their mass. During four years (2002-2006), Greenland lost up to 60 cubic miles of ice every year, and Antarctica lost more than 30 cubic miles during 2002-2005. At the same time, glaciers are shrinking all over the world, including, Alaska, Himalayas, Rockies, Africa, and Andes (NASA). While the evidence obtained through observations, studies and researches is quite compelling, still there are adherers to the theory that humans have nothing to do with the process of climate change. In particular, they believe that it is natural causes that should be blamed for the changes in the Earth’s climate. Among such natural causes are increased solar radiation and volcanic eruptions. The planet is bombarded by heat and solar energy; however, it has been proven that the amount of this energy is not enough to cause climate change and global warming in particular. In accordance with the data obtained from the National Center for Atmospheric Research, “the strongest evidence for this is the record of satellite measurements of solar output since the late 1970s that show no increasing trend in solar output during the period of global warming” (Money). In fact, variations in solar energy output do not exceed 0.1%. Some also believe that volcanic eruptions influence the Earth’s climate and cause climate change. The matter is that volcanos erupt significant amounts of sulfur dioxide into the stratosphere where it converts to sulfuric acid which, in its turn, forms fine sulfate aerosols. The latter cause cooling of the troposphere due to the fact they increase the reflection of solar radiation. However, research finding show that CO2 emissions of all subaerial and submarine volcanoes are less than CO2 emissions released as a result of human activities. More specifically, in 2010 humans released 35 gigaton of CO2 emissions, and this amount is 135 higher than the highest global volcanic emissions of almost 0.3 gigaton a year (USGS). Thus, as the evidence shows, solar activity and volcanic eruptions should not be regarded as the most important causes of climate change. Today, there are two points of view on the nature of climate change. The first one is the idea that natural factors, such as solar activity and volcanic eruptions, have a significant influence on climate patterns. The second point of view is that climate change is actually human induced and results from anthropogenic factors. The second idea appears to be the most relevant and plausible, and numerous studies prove this fact. In particular, they show that the problem of climate change is caused by human activities which result in the increase of amount of greenhouse gases and aerosols in the atmosphere and changes of landscape. Works Cited Environmental Defense Fund. "How Are Humans Responsible for Global Warming?.” Environmental Defense Fund. Environmental Defense Fund, 2013. Web. 16 Jun 2015. . Foster, P., and V. Ramaswamy. "Changing in Atmospheric Constituents and in Radiative Forcing." Intergovernmental Panel on Climate Chang. IPCC, 2007. Web. 16 Jun 2015. . Hartmann, D. L., M. G. Tank, and M. Ristucucci. "Observations: Atmosphere and Surface." Intergovernmental Panel on Climate Chang. IPCC, 2013. Web. 16 Jun 2015. . Intergovernmental Panel on Climate Change. "Climate Change 2007: Synthesis Report." Intergovernmental Panel on Climate Chang. IPCC, 2007. Web. 16 Jun 2015. . Mooney, C. "No, The Sun Isnt riving Global Warming." Washington Post 23 February 2015, n. pag. Web. 16 Jun. 2015. . NASA. "Climate Change: How Do We Know?."climate.nasa.gov. NASA, 9 Jun 2015. Web. 16 Jun 2015. . US Geological Survey. "Volcanic Gases and Climate Change Overview." USGS.gov. USGS, 13 Apr 2015. Web. 16 Jun 2015. . WWF. "Deforestation and Climate Change." Panda.org. WWF. Web. 16 Jun 2015. Read More