Free «Global Warming and its Effects» Essay Sample

To start with, it should be ascertained that global warming is the process of gradual increase of the average temperature of the Earth, which is caused by high concentration of greenhouse gases in the Earth's atmosphere. In 1960s, the global warming became a subject of discussions for the first time, and in 1980, the UN officially acknowledged climate change as one of the world’s urgent problems. Nowadays, global warming is considered one of the most acute environmental issues of human civilization. The fact of global climate change is confirmed by scientific researches and is not disputed by the majority of scientists. Climate change has already begun to affect people's lives all around the world, and its effects continue to grow. The adverse effects of global warming involve numerous changes of the physical environment, which have deleterious effects on the composition and productivity of natural ecosystems, functioning of the socioeconomic systems, and human welfare.

The climate change may be the result of natural internal processes due to external influences, both anthropogenic and non-anthropogenic. It should be stated that the climate on the Earth ultimately depends on the balance of absorbed and reflected solar energy. Russel (2007) admitted that high reflectivity of the planet, albedo, leads to the lowering of the surface temperature and makes the climate colder. Vardiman (n.d.) found that the modern climate of the Earth is largely determined by a high level of heat absorption in the atmosphere, which is associated with the greenhouse effect. One must bear it in mind that the phenomenon of the greenhouse effect is atmosphere’s property to transmit the solar radiation and to keep the terrestrial radiation, which contributes to the accumulation of heat on the Earth. The human activity increases the concentration of atmospheric greenhouse gases, which leads to the greenhouse effect and disturbance of the Earth's heat balance. Coal power stations, automobile’s exhaust fumes, factory smokestacks, and other sources of pollution emit around 22 billion tons of greenhouse gases each year.

The greenhouse effect is a result of high concentration of carbon dioxide in the atmosphere. Russel (2007) noticed that carbon dioxide is transparent to shortwave radiation coming from the Sun, but it strongly absorbs energy in the long-wave part of the spectrum, which re-emits by the Earth back into space. According to Vardiman (n.d.), carbon dioxide is a strong absorber of rays in the infrared part of the spectrum but almost transparent to the ultraviolet and visible rays. It means that the incoming solar radiation, mainly ultraviolet and visible part of the spectrum, is not constrained by the admixture of CO2 in the atmosphere, in contrast to infrared radiation of the Earth. In this context, carbon dioxide absorbs the outgoing radiation by warming the lower layers of the atmosphere, which radiate the solar energy back to the surface of the Earth.

Ozone (O3) is the gas responsible for temperature distribution and circulation system in the stratosphere. According to UNEP (2009), O3 molecules are also important in the process of heating of atmospheric gas (due to absorption of solar ultraviolet radiation in the stratosphere and infrared radiation of the surface in the troposphere), and in the process of cooling (due to the emission of absorbed energy). Johansen (n.d.) stated that the increase of the amount of carbon dioxide in the stratosphere decreases its temperature by 10-15°C as CO2 molecules are actively involved in the process of cooling of stratospheric air. In this case, the author proves that high concentration of carbon dioxide in the lower atmosphere leads to a decrease of ozone in the stratosphere, which enhances greenhouse effect and has a negative impact on the global warming (Johansen, n.d.).

In this case, human activity is one of the main causes of global warming because about half of all greenhouse gases, produced by the economic activity of mankind, remain in the atmosphere. Modern scientific researches proved that the average temperature on the Earth has increased by 0.7°C since the industrial revolution in the second half of XVIII century. Time for Change (2007 ) says that the warming of atmosphere's over the past 50 years was a result of the combustion of carbon dioxide (CO2), methane (CH4), and Chlorofluorocarbon (CFC), which are main gases causing the greenhouse effect. Burning of oil, natural gas, and coal became the result of nearly three-quarters of all anthropogenic emissions of greenhouse gases over the past 20 years. Most of remaining emissions are caused by changes in the landscape, especially deforestation and mining.

Apart from human activity and the greenhouse effect, global warming may be also caused by the increase of solar activity, changes of the Earth's orbit, and volcanic emissions. It is a common fact that all climatic processes on the planet depend on the activity of the Sun. In this case, Time for Change (2007) proves that even minimal changes of solar activity may certainly affect the weather and climate of the Earth. Recent researches showed that one of the reasons of the global warming is additional solar energy passing through the depleted ozone layer (Time for Change, 2007). On the other hand, cyclical climate change is largely caused by the change of Earth's orbit along with the change of the inclination angle of Earth's axis. Significant changes of the orbital motion of the planet are supposed to influence the Earth's radiation balance, which may lead to the climate change (Missouri Department of Natural Resources, n.d.). Volcanic activity is considered to be one more reason for global warming, which emits a large amount of sulfuric acid and carbon dioxide in the Earth's atmosphere. Subsequent long-term reduction of volcanic activity increases the atmosphere transparency, which later allows carbon dioxide to enhance the greenhouse effect on the planet.

According to Lindzen (2006), Over the last hundred years, the average temperature of the surface layer of the atmosphere increased by 0,5-0,8°C, the area of snow cover in the Northern Hemisphere decreased by 8%, and sea level rose by 10-20 inches. Some scenarios of climate change show that the average temperature of the globe is expected to increase by 1.4–5.8°C by 2100. In addition, the periods of hot weather are expected to become protracted and will be characterized by the extreme temperatures. Nowadays, drought affects nearly 2 percent of the land, and scientists predict that up to 10 percent of all continents will be hit by drought in 2050. At the same time, the situation will greatly depend on the region of the Earth, and the climate differences will be extremely difficult to foresee. For example, Europe is predicted to face a short ice period due to the possible slowdown of the Gulf Stream.

Global warming accelerated the process of evaporation in a colder climate zones and influenced the melting of glaciers. Borenstein (2011) claims that the Antarctica and Greenland keep approximately 98-99% of the planet's freshwater ice. In this case, global warming threats to melt the Greenland’s ice surface, which will increase the sea level by 7 meters. Melting of the Antarctic ice and mountain glaciers led to the fact that the sea level rose by 8 inches during the period between 1870 and 2001 (Lindzen 2006). Over the last few years, the melting speed of glaciers on the planet has reached a record level since the very beginning of observations. In addition to it, the number and size of mountain glaciers and snow is decreasing rapidly all around the planet. For example, according to the National Geographic, the mountainous state of Montana counted 150 glaciers in 1910, and in 2007, there were only 27 of them (Chadwick 2007).

Talking into account the whole planet, the Asia will suffer from frequent flooding as a result of the greenhouse effect and global warming, and Africa, on the contrary, will face the problem of frequent water shortages. In this context, partial flooding of the Asian continent and the appearance of the new land near the African continent are expected. Lindzen (2006) stated that the increase of the sea level for 1 meter may force 145 million people to live in the flooding area. The risk of floods can also lead to the disappearance of some countries, such as the Netherlands, Pakistan, Israel, the major part of Japan, and some other small islands. According to Vardiman (n.d.), such populous urban areas as London, Mumbai and New York may also appear under the water. At the same time, when some parts of the planet will feel the threat of flooding, other territories may face the lack of potable water. In a number of arid regions, such as Central Asia, Australia, Mediterranean, and South Africa, the situation will become more complicated due to the significant reduction of the rainfalls.

Global warming will also increase the number of various natural disasters, such as devastating hurricanes, tornadoes, earthquakes, and tsunamis. Vardiman (n.d.) admitted that natural disasters on the planet became 4 times more frequent than 20 years ago. According to his data, in 1980s the world faced around 120 natural disasters per year, whereas nowadays this number is already approaching 500 (Vardiman, n.d.). The greatest number of natural disasters is expected to happen in densely populated areas, which are situated on the ocean coasts or banks of large rivers. The increase of warmth in the atmosphere makes the planet hotter, which leads to irreversible climate change. Borenstein (2011) admits that the growth of annual temperature of the surface layer of the atmosphere will rather strongly affect continents than the oceans, which will cause a radical restructuring of the natural zones of the continents. The offset of some climate zones into the Arctic and Antarctic latitudes will happen in the closest future.

Global warming and the greenhouse effect will also lead to melting of permafrost, which now covers 1/4 of the Northern Hemisphere. Borenstein (2011) asserts that the rapid melting of permafrost and rising of the sea level makes the Arctic Ocean advance on the land with an average speed of 3-6 meters per year. According to Pfeffer (2011), precipitation is expected to increase in moderate latitudes during the winter time while rainfalls are expected to decline in the tropical latitudes by 20 percent, especially during the summer time. In addition, global warming is predicted to increase the frequency of forest fires, peat fires, reduce the productivity of forests, and lead to the soil erosion. Climate change will significantly affect the animal world of the Earth, as the planet’s flora and fauna may reduce by a half. Srivastava (2010) assumes that global warming will change the habitats of many living entities. In this context, numerous species of animals and plants will disappear because of inability to adapt to a rapidly changing environment.

Apart from increasing the sea level, global warming is expected to cause changes in the quantity and distribution of rainfalls, which will make tornadoes more frequent. Vardiman (n.d.) noticed the increase of the number and intensity of tornadoes and hurricanes in the United States of America in the early XXI century. Vardiman’s scientific researches show that in the second half of the XX century, tornadoes appeared in the U.S. only in the middle of March, and at the beginning of the XXI century, they started to appear in February. In addition to it, global warming and climate change will significantly increase the total number and intensity of tornadoes in the future. Epstein (2011) stated that increase of the average temperature on Earth will intensify and strengthen the tropical storms and typhoons, which receive the energy from the superheated ocean. The researcher claims that the temperature of the ocean has the direct relation to the strength of developing tropical storm or tornado (Epstein 2011). The brightest example of global warming may be considered the devastating hurricane ‘Catherine’, which was one of the most powerful natural disasters during the whole history of the USA. Another proof for the climate change is the high number of super powerful tornadoes, which affect Texas, Oklahoma, Kansas, Missouri, and Iowa each year.

Global warming may also trigger a great number of earthquakes and tsunamis. Meares (2009) found that the overheating of the ocean creates additional thermal stresses in the lithosphere, which increases the risk of intensive earthquake and, as a result of it, tsunami. According to Steven (2011), one more reason for tsunami is that melting of Antarctic ice makes the Earth’s crust more fluid, which, in its turn, leads to significant changes of the sea level and the shift of the seabed. The current situation is extremely favorable for the creation of numerous underwater earthquakes, which may lead to the strong tsunami.

The largest tsunami during the entire period of observations occurred in December 2004, which arose on the volcanic rift near the island of Sumatra. Another strong tsunami happened in Japan in March 2011, which was preceded by a powerful earthquake. The disaster took more than 10 000 people’s lives and caused large destructions and fires. In this case, scientists have found that intensive melting of glaciers has the great influence on the increase of quantity and power of earthquakes, floods, and tsunamis in the most unexpected places. It is a proven fact that long-term climate change affects the motion of lithospheric plates and forms the feedback. Monsoons may be also responsible for accelerating the movement of Hindustan tectonic plate more than an inch per year.

Scientists state that global warming may also affect volcanic activity by increasing the number and intensity of the volcanoes on the planet. In the next few decades, the melting of Arctic ice and permafrost will awake the dormant volcanoes and will also make volcano eruptions in Antarctica, Alaska, Aleutian Islands, and Patagonia more frequent. Thompson (2007) noticed that ice facilitates the process of revitalization of volcanic activity by exerting a great pressure on the Earth's crust. The most recent example of an intensive volcanic activity was Iceland where volcano eruption in April 2010 caused not only problems for the international airline industry, but also damaged wildlife by polluting a vast territory with a thick layer of volcanic dust.

From the other side, volcanic activity has the direct impact on the strengthening of global warming. Volcanic eruptions emit a large amount of carbon dioxide, carbon monoxide, and sulfur dioxide in the atmosphere. In this context, one of the causes of global temperature change is the increase of the number and power of volcanic eruptions. USGS (n.d.) states that climax periods of volcanic activity increase the presence of greenhouse gases of volcanic origin in the atmosphere. In the period from 1850 to the present time, the index of volcanic activity increased by 80-85%.

Thus, the ongoing research proved that global warming is caused by both natural and anthropogenic factors and has a negative influence on the planet. The consequences of global warming and climate change are already evident today and include frequent and intensive natural disasters such as tornadoes, earthquakes, tsunami, and floods. In this case, global warming is the planet's biggest threat as it causes considerable economic damages, threatens the existence of a stable ecosystem, and creates the risk for human life and health. The current situation proves that climate change may lead to dangerous consequences in the future. In order to prevent such a scenario, mankind should take appropriate preventive measures against global warming.