· Essays

Global Warming

Earth’s temperature is controlled by the balance of the incoming solar energy from the Sun and the terrestrial energy radiated back into space.

This balance is controlled by the composition of the planet’s surface and more importantly, the composition of the atmosphere. Scientific study has demonstrated beyond reasonable doubt that human influence is changing both the composition of the planet’s surface and the atmosphere, and in effect is warming the climate on Earth.

Processes in the climate system which decrease warming (by increasing terrestrial radiation) are called negative feedbacks. They are few but powerful and can broadly be described as processes helping energy radiation escape Earth. For example clouds reflect large amounts of solar energy back into space. Positive feedbacks increase warming (by decreasing terrestrial radiation) and they can be divided into four distinct categories, relating to aerosols, gases, oceans and forests.

Aerosols are any type of dust or liquid or solid particles floating in the atmosphere. In the polar areas aerosols absorb large amounts of energy (the distinct characteristics of each type are modified by its distribution and properties) and create a positive feedback. At lower latitudes (closer to the equator) the absorption of aerosols generates a low negative feedback.

Gases are matter in a state in which atoms and molecules are diffused and move freely. Water vapor is the most significant gaseous absorber of terrestrial radiation and thus creates the largest positive feedback. Carbon dioxide comes in second in terms of feedback. Methane is more potent than CO2 but there is less of it in the atmosphere. Most of the other gases in the atmosphere are more potent absorbers of energy than CO2, but contribute less because of their relative scarcity.

Oceans are the principal component of Earths hydrosphere and make up 71% of its surface area (NOAA). As bodies with a low albedo absorb more energy than high albedo bodies, higher latitude sea-ice, also known as polar ice, starts to absorb more energy when it melts into liquid water. The increase in energy absorption creates a positive feedback.

Forests are a significant part of the Earth’s biosphere and form approximately 30.3% of total land area or 9.4% of the entire planet’s surface (FAO). By capturing CO2 from the atmosphere, forests storage the gas and prevent it from absorbing energy. At higher latitudes though, because of their low albedo foliage, forest tend to absorb more energy than they prevent the CO2 from absorbing – in effect creating a positive feedback.

According to many reports the growing human pressure on the positive feedbacks of the climate system may overpower the negative feedbacks, causing a warmer climate. Scientific study has shown the global increase of aerosols (air pollution), the increase of gas in the atmosphere (CO2), the increase of water over ice (melting polar ice), and the decrease of low latitude forests. A warmer climate is characterized by a range of problematical effects concerned with rising sea levels, receding glaciers and polar ice, extending tropical areas, and desertification as well as loss of biodiversity and health-related issues.

The sea level rise between 18 to 59 centimeters by the year 2100 predicted as “likely” by the Intergovernmental Panel on Climate Change (IPCC 11) may lead to negative outcomes for many nations. Pacific islands such as Nauru the Marshall Islands may experience extensive loss of territory (Watson, Marufu and Moss 15). Coastal areas in cities like New York may become under water, with Manhattan entirely submerged. Some low-lying countries, for example the Netherlands and Pakistan may lose extensive parts of their territory, or be entirely inundated. According to the OECD, nations with lower income rates will experience the strongest effects (OECD 7).

Measurements of glaciers (large bodies of land ice and permafrost found in all climate zones, including the tropics, but most common in the Polar Regions) have shown that as of 2006 all glaciers around the world are receding and losing mass (WGMS). In the Alpine mountains of Europe, the receding ice and snow may put pressure on the resort industry to move skiing areas higher up the slopes, which may lead to a loss of revenue. In Switzerland, Austria, France, Germany and Italy resorts and villages may come under threat from an increasing number of landslides. According to a European study, reported in the New Scientist, the temperatures in rock and mud in the Swiss Alps increased by 0.5°C to 1.0°C from 1987-2001 (New Scientist). In mountainous areas of South America, Africa and Asia, the receding glaciers may introduce water shortages possibly complicating irrigation and water usage for agriculture in mountain communities. Effects on agriculture may be linked with increases in economic poverty. In all parts of the world national parks may experience a decline in the quality of services relating to their aesthetical beauty, and access to recreational activities.

The degradation of land, destruction of soil structure and loss of organic matter, also known as desertification may complicate food production, increase prices, and decrease the farmer’s competitiveness in the marketplace. As such, in addition to being an environmental concern, desertification may also contribute to poverty and social problems.

The impact of climate change on biodiversity depends on the degree of susceptibility of the particular system, also known as ecosystem sensitivity. As biodiversity is measured by the range of species in an ecosystem, the loss of species recorded around the world may be an indicator of the effects of a changing climate on the whole ecosystem. Ecosystems that are close to equator, and to the polar areas, may be especially fragile.

A warmer climate may create serious health effects, complicating the physical and mental well being of populations in different areas, including Europe and North America. New vectors of Malaria and other viruses may compromise the health of an increasing number of people. Accompanied by desertification and decreasing accessibility of water resources, areas in poorer regions may be especially strongly affected.

In order to mitigate such effects of global warming on sea levels, glaciers, polar ice, tropical areas, land, biodiversity and health the increasing in positive feedbacks needs to be slowed down. According to the 2007 Bali Climate Declaration, “based on current scientific understanding, [the limiting of global warming to no more than 2 ºC above the pre-industrial temperature] requires that global greenhouse gas emissions need to be reduced by at least 50% below their 1990 levels by the year 2050. “

One comprehensive solution which holds the promise of limiting global temperatures to the extent proposed by the IPCC as well as corresponding with the interests of both the economical and environmental perspectives is the hydrogen economy. For the adoption of the hydrogen economy, and to meet the rising energy consumption throughout the world, the involvement and cooperation of business, government and the third sector would be required. In a market environment the strong market incentives for such restructuration would be the popular demand and government subsidies matching or exceeding current subsidies for non-renewables. The hydrogen economy can best be described in two distinct parts by creating a differentiation between energy production (from renewable solar, wind or other sources) and the energy currency –hydrogen.

Energy produced from resources replenished in a practical timescale by natural phenomena is called renewable energy; non-renewables resources are not naturally replenished. As of 2006, approximately 88% of the total world energy consumption was produced from the non-renewable resources – oil, coal and gas (BP). With a comparatively low median price per kilowatt hour, ready availability and simple distribution, non-renewables remain the most economical option in many parts of the world. Nonetheless, the price of non-renewables has been steadily increasing over the past 15 years (BP), while the price of renewable energy is experiencing a gradual decrease (U.S. Department of State 22). One report expects “a rise in the cost of power generation based upon fossil fuel combustion and a relative improvement in the competitive position of an increasing range of renewable energy technologies.”, also adding that “over the next two decades, the cost of renewable technologies (particularly those that are ‘directly’ solar-based) is likely to decline markedly as technical progress and economies of scale combine to reduce unit generating costs.” (Hanley and Owen 306)

Largely due to scientific breakthroughs in nanotechnology, the efficiency of renewables, especially that of solar power has increased while the price has become more economical. As of January 2008, the latest generation solar power has reached a nominal wholesale price of 21.34 US cents per kilowatt hour based on prices in California (SolarBuzz) which may only be twice as expensive as ‘normal’ power. It is also worth noting that the price of solar energy depends on the cost of the installation; the cost of fuel is free. When comparing with nuclear energy, a concentrating solar thermal tower which is relatively easily constructed may produce 200 megawatt-hours of power depending on the size while a typical nuclear power station (which is time and resource consuming to construct) outputs anywhere from 1000-4000 megawatt-hours worth, also depending on the size.

In addition to a power generation technology, a second part is needed in a comprehensive energy system. In order to make the electricity generated from renewable resources run cars and planes, it needs to be transported using some sort of a currency. Traditional electricity cannot be stored for later usage and does not offer the flexibility offered by gaseous currencies such as natural gas and hydrogen. Hydrogen delivers the ease of use that consumers may have come to expect while being environmentally friendly. According to one report the price of hydrogen delivered to consumers would be no more than 50% more expensive than natural gas (Monbiot 137).

In a hydrogen economy the currency can be transported using pipelines and transformed back into electricity by a fuel cell in the consuming vehicle or other appliance. Fuel cells work by capturing electrons from hydrogen and oxygen to create an electrical current. As electrons become electricity the elements themselves are bound together becoming hot water, and then evaporate. Water vapor may also be recaptured and used for various applications (in the case of NASA spacecrafts which use hydrogen fuel for spaceflight, it becomes drinking water for the astronauts (NASA)).

Although the range of problems introduced by climate change is large and varied around the globe, they may be resolved through a limited set of renewable energy solutions. Both the hydrogen production and the hydrogen currency form an integral part of the carbon emission free economy. Economists report that “[renewables] bring significant additional advantages that are not generally quantified.” (Hanley and Owen 307) The water vapor produced when converting hydrogen to electricity is a benign emission and is easily captured. As a pollutant free system the hydrogen economy contributes to clearer skies and better health for the people, a richer nature and a more varied biological diversity in the biomes around the world.  With the economics of scale the mass production of renewable energy may bring the price of renewables to rates which are not only cheap enough for the environmentally conscious but economical enough for widespread adoption.

Bibliography

BP. Statistical Review of World Energy. New York: BP Amoco, 2007.

FAO. Global Forest Resources Assessment. New York: FAO, 2005.

Hanley, Nick and Anthony David Owen. The Economics Of Climate Change. New York: Routledge Press, 2004.

IPCC. Climate Change 2007: Synthesis Report. New York: Cambridge University Press, 2007.

Monbiot, George. Heat: How to Stop the Planet from Burning. New York: South End Press, 2007.

NASA. Closing the Loop: Recycling Water and Air in Space. 2003. 16 January 2008 <www.nasa.gov/pdf/146558main_RecyclingEDA(final)%204_10_06.pdf>.

New Scientist. "Mountain Concern." New Scientist January 2001.

NOAA. Ocean. 16 January 2008 <http://www.noaa.gov/ocean.html>;.

OECD. "Policies to address climate change: the OECD experience and relevance for Mexico OECD Environment Directorate." International Forum on Public Policies for the Development of Mexico. 2007.

SolarBuzz. Solar Electricity Prices. 2008. 16 January 2008 <http://www.solarbuzz.com/SolarPrices.htm>;.

U.S. Department of State. "Clean Energy Solutions." Economic Perspectives (2006).

Watson, Robert Tony, Zinyowera C. Marufu and Richard H. Moss. The Regional Impacts of Climate Change: An Assessment of Vulnerability. New York: Cambridge University Press, 1998.

WGMS. Clacier Mass Balance Data 2003/2004, 2004/2005, and 2005/2006. 2008. 16 January 2008 <http://www.wgms.ch/mbb/mbb9/sum06.html>;.


Adapted from Problem & Solution: Global Warming for BFM.

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