Global Warming, Climate Change and the Greenhouse Effect, Essay Example

Global Warming

Global warming is the general increase in the earth’s temperature, thought to permanently alter the earth’s climate. Global warming takes into consideration the average temperatures of the earth’s atmosphere and oceans, tracking these temperatures over time. According to historical records, 20 of the hottest years in history have been recorded in the past 25 years. 2010 and 2005 were the hottest years ever recorded in history. As the table below depicts, 2009, 2007, 2006, 2003, 2002 and 1998 follow.

The values that are depicted in the table above are anomalies from the mean of 13.9 ?C which is the 1901-2000 mean global temperature . For example the 2012 +0.45 ?C anomaly is added to 13.9 ?C to give a global average temperature of 14.35 ?C. Furthermore, the 2000s has been found to be the warmest decade recorded in history. Also all of the past three decades have been hotter than the preceding decade as shown below. The odds that this is a natural occurrence is estimated to be 1:1 billion.

Climate Change

This is the alteration of the distribution of regional or global weather patterns as a result of increasing carbon dioxide levels. Climate change is limited to the carbon dioxide that emanates from the use of fossil fuels. Climate change may either refer to a change in the average weather conditions or the extent to which weather conditions are experienced. For a long time it has been held by scientists that the main cause and contributor of global warming is the increase in the amount of greenhouse gases in the atmosphere. The biggest component of greenhouse gases is carbon dioxide. This claim is founded on the fact that research showed that in 1958, the amount of carbon dioxide in the atmosphere was at a level of 315 ppm (parts per million) . In 2008, the amount of carbon dioxide had risen to the level of 385 ppm.

Over the past three decades, human activities that relate to industrialization have increased drastically as nations seek to realize the final stage of economic growth and development, the age of high mass consumption. This has led to an increase in the amount of carbon dioxide emissions from factories, plants and other activities that utilize fossil fuels. This is directly related to the increasing levels of carbon dioxide in the atmosphere. According to research, the climatic conditions experienced today would not have happened if the human race did not exist. In essence, it is virtually not possible for natural forces to have raised the CO2 levels to the point there at today. This is undoubtedly the main trigger and cause of global warming. This provides undeniable evidence that the higher the level of carbon dioxide the warmer the earth gets.

Greenhouse Effect

The greenhouse effect is the process by which greenhouse gases absorb thermal radiation and re-radiate it back towards the earth. During this process the re-radiated rays raise the atmospheric and surface temperatures.

Scientific Consensus on Climate Change

While the issue of climate change has been an issue that has drawn much support and criticism, the majority (at least 95%) of scientists hold that climate change over the past 100 years has mainly been a result of human activities. The statements published by numerous scientific organizations have not been formally rejected or opposed.

The diagram depicts the energy that is entering, reflected, absorbed and emitted by the earth’s surface and atmosphere. The incoming solar radiation (shortwave radiation) is a combination of visible, ultraviolet and limited infrared energy. This energy is usually around (watts per square meter). Some of this radiation is reflected back into space by the clouds and the atmosphere (about), some of it is absorbed by the atmosphere (), some of the energy is reflected by the surface () and a considerable portion (47%) is absorbed by the earth’s surface (). The reflected energy is in long wave form. Long wave emissions from the upper atmosphere and the surface of the earth raise the temperatures of the lower atmosphere.

Greenhouse gases in the upper atmosphere absorbs of the long wave radiation from the surface of the earth. Only  of long wave radiation leaves the upper atmosphere into space. This is largely due to the fact that only is emitted by the upper atmosphere,  by clouds and is emitted through the atmospheric window. The greenhouse gases reflect of long wave emissions back to the surface of the earth significantly increasing temperatures.

The figure clearly depicts the energy balance system where the amount of energy that comes into the earth is equal to the amount of energy that leaves the earth. As the figure depicts

Where  is the reflected solar radiation and is the outgoing infrared radiation

The arrows indicating surface radiation absorbed by atmosphere and infrared radiation reflected to the surface of the earth from the atmosphere is directly linked to the presence of greenhouse gases. Greenhouse gasses are responsible for the absorption and re-radiation of long wave (infrared) emissions)

Positive and Negative Feedback

Climate change feedback is the response realized in when one factor causes a change in a second factor and a change in the second element causes a change in the first factor. This generally determines the sensitivity of the climate within a given geographic location. Positive feedback occurs when change in the second factor amplifies the first factor. On the other hand, negative feedbacks occur when change in the second factor diminishes or moderates the first factor

Examples of Positive and Negative Feedback

Positive feedback

1. Increase in the earth’s average temperatures (global warming) leads to an increase in the amount of water vapor in the atmosphere. This is because the general increase in temperature causes a general increase in the rate of evaporation. This increase in the amount of water vapor in-turn causes an increase in atmospheric temperature as more radiation is trapped by the vapor.
2. Global warming has been found to cause the increase in arctic temperatures. This has caused the thawing of permafrost peat bogs which release methane. This increase in methane (a greenhouse gas) increases the amount of long wave radiation retained by the earth’s atmosphere and reflected back into the earth’s surface, futhher increasing the earths average temperature (atmospheric and surface temperatures)

Negative feedback

1. An increase in the earth’s temperature would lead to increased evaporation and a resultant increase in water vapor. This would result in the increase in the formation of low lying clouds which reflect more solar radiation into space. This increase in solar radiation reflection reduced solar radiation heating effect on the lower atmosphere and the earth’s surface. This reduces the average temperature of the earth.
2. The ocean absorbs a portion of the carbon dioxide emitted as a result of human activity. However, as carbon dioxide emission increase, the ocean becomes more acidic and cannot absorb carbon dioxide any further. The general increase in CO₂ leads to an increase in the temperature of the earth’s surface and its oceans increase. This increase in the temperature of the ocean reduces its ability to absorb carbon dioxide, thus leading to increased CO₂ in the atmosphere. This results in further heating.

Correlation between Global Temperature and CO₂ Emissions

There is a generally positive correlation between average global temperatures and the levels of CO₂ emissions. Scientists have long shown that increasing global temperatures can be associated with the increase in CO₂ emissions. This is because CO₂ emissions retains long wave radiations from the earth’s surface, increasing the temperature within the earth’s atmosphere, increasing the average temperature. This is a positive correlation and it is depicted in the graphical representation below.

If the temperature of the earth rises enough so that the polar ice caps begin to melt, global temperature would rise. This is because this increase will cause a negative climate change feedback and a stronger positive climate change feedback. The melting icecaps would increase the amount of water in the earth’s oceans. The increase in temperature would increase the rate of evaporation increasing the amount of low-lying clouds. These cloyds would reflect solar radiation into space, reducing global temperatures. However, the increase in evaporation would increase the amount of water vapor in the atmosphere which would retain long-wave radiation from the surface of the earth, increasing global temperatures. Furthermore, the melting icecaps would lead to increased methane gas emissions from melting permafrost peat bogs. This would increase the amount of long wave radiation absorbed in the earth’s atmosphere.

Global Warming Mitigation and Management Strategies

There are a number of strategies that have been developed to tackle global warming. They include:

• Placing Constraints on the use of Natural Resources

Natural resources are the corner stone of any endeavor towards economic growth. This is because economic development relies on industries, which in turn depend on environmental resources for raw materials. It is common belief that economic growth is associated with the degradation of the environment. This is because the goal of economic growth is the progress and growth of man and not the improvement of the environment. However, this growth is only attainable and feasible within ecological constraints. It is therefore paramount that economic growth be realized with these ecological constraints. For it is within these constraints, that the sustainability of economic growth be realized. In order to achieve the final stage of economic growth, the age of high mass consumption, it is essential that the rate of economic growth be sustained over a considerable period of time (Purdey, 2010). By observing these constraints, environmental damage can be mitigated and possibly averted.

The anthropocentricism theory places human beings as the most important species on the planet. This is true, considering human beings are at the highest intellectual level as compared to other species on the planet (Purdey, 2010). This theory however holds that natural resources are solely meant for exploitation by human beings. However, this intellectual superiority can be either beneficial or detrimental to human beings. If used carefully, economic growth can be attained while preserving the environment. Otherwise, there would be uncontrolled economic growth at the expense of the environment. For example, Australia is one of the largest producers of Uranium. As a result of extensive Uranium mining, environmental degradation impacts have seen land become useless due to nuclear radiation that is a result of Uranium mining (Bayliss, van, & Bartolo, 2012). Without controlled economic growth, natural resources are rendered inadequate.

• Carbon Pricing Scheme (Carbon Tax)

Industrialists hold the notion that restrictions in natural resources can hamper economic progress. However, environmental laws and regulations can be put in place to counter the effects economic activities have on the environment. A good example is the Carbon Tax (Carbon Pricing Scheme) that was implemented on 1st July 2012 by the Australian Government. This was meant to counter the massive carbon emissions from business entities. The policy applied a $10 per ton of CO₂ greenhouse on business entities that emitted over 25,000 tonnes of carbon per year (Gaas, Sawyer, & International Institute for Sustainable Developmen, 2013). Revenues from this tax policy is direct towards environmental upgrading strategies by the Australian Government. Through instituting, policies, laws and institutions to check and counter cases of environmental degradation as a result of economic activities such as global warming, economic growth can be pursued with little to no limits. Mitigation measures are essential in achieving economic growth

• Renewable Energy

In order to counter this, renewable energy sources provide cheaper and readily available resources. The availability of solar, geothermal and wind energy provides governments with environmentally friendly options to fossil fuels. Through these energy sources, economic growth can be sustained while ensuring little to no damage to the environment. Energy is a subject that has become prevalent in the 21st century. With increasing evidence of the impacts of global warming, from the melting icecaps in the north and south, to the increasing incidents of adverse weather and the gradual change in the global weather patterns, renewable energy is undoubtedly the answer to all these problems. Solar energy is the most readily available source of energy on the planet. Since solar energy is generated from the sun, all which is required is a reasonable exposure to either sunlight or solar radiation (Zuchora-Walske, 2013). This is easily achieved as the earth is constantly exposed to the sun’s radiation and light. This means that anyone with a reasonable exposure to the sun can generate solar energy.

There are a number of negative effects of reducing global warming. The most prominent is the effect on economic growth and development. Mitigating global warming entails curtailing economic activities that require fossil fuel energy. This is because fossil fuels are attributed to the increase in CO₂ emissions in the world. This would considerably hamper development.

Works Cited

Bayliss, P., van, D. R., & Bartolo, R. E. (2012, January 01). Quantitative Ecological Risk Assessment of the Magela Creek Floodplain in Kakadu National Park, Australia: Comparing Point Source Risks from the Ranger Uranium Mine to Diffuse Landscape-Scale Risks. Human and Ecological Risk Assessment: an International Journal, 18(1), 115-151.

Gaas, P., Sawyer, D., & International Institute for Sustainable Developmen. (2013). Regulating carbon in Canada: Divergent Approaches: Greenhouse Gass mitigation in Canada and Australia. Winnipeg: International Institute for Sustainable Development.

Oskin, B. (2013, June 7). Africa’s Worst Drough Tied to Wests Pollution. Retrieved 28 2013jULY, from Live Science: http://www.livescience.com/37282-north-america-pollution-caused-africa-drought.html

Purdey, S. J. (2010). Economic Growth, The Environment and International Rlations: The Growth Paradigm. London: Routledge.

Zuchora-Walske, C. (2013). Solar Energy. Minneapolis: ABDO Pub. Co.