Climate Change: Causes, Effects, and Solutions
Climate Change: Causes, Effects, and Solutions
© 2013 by Jensen DG. Mañebog
On Global Warming and Climate Change
Climate change is “a change in the statistical properties of the climate system when considered over long periods of time, regardless of cause” (“Climate change,” n.d.). Using this definition, climate variations over periods shorter than a few decades, like El Niño, do not exemplify climate change.
The term is often used to particularly denote the climate change caused by human activity, as opposed to environmental changes caused by Earth’s natural processes. In this sense, the term climate change has become synonymous with anthropogenic (human-caused) global warming. To differentiate the two related concepts, global warming refers to surface temperature increases, whereas climate change comprises global warming and everything else affected by rising greenhouse gas levels.
Taken together, global warming and climate change refer to “measurable increases in the average temperature of Earth’s atmosphere, oceans, and landmasses” (Mastrandrea, 2009). The Earth is observed to be undergoing a period of rapid warming fundamentally caused by increasing levels of heat-trapping gases, called greenhouse gases, in the atmosphere.
The greenhouse gases and greenhouse effect
The sun provides the energy that lights and warms the earth. The sun’s short-wave radiation enters the atmosphere and is absorbed by the earth’s surface. In turn, the earth’s surface releases to space some of this heat as long-wave infrared radiation. However, a fraction of this long-wave infrared radiation remains trapped in earth’s atmosphere, soaked up by some atmospheric gases. “Absorbing and reflecting heat radiated by Earth, these gases act somewhat like the glass in a greenhouse, and are thus known as greenhouse gases” (Schneider, 2009).
The greenhouse effect refers to the process through which the greenhouse gases retain the radiant energy or heat provided to Earth by the Sun. All life on earth depends on this greenhouse effect, for without it, the earth would be too cold, about -18°C (0°F), and ice would cover the whole planet.
Greenhouse gases are thus necessary to sustain life on earth as they provide the earth with necessary heating mechanism. However, since the start of the Industrial Revolution (mid-1700s), human activities such as burning of fossil fuels (like coal, oil, and natural gas) have perpetually added more of these gases into the atmosphere. “With more greenhouse gases in the mix, the atmosphere acts like a thickening blanket and traps more heat” (Mastrandrea, 2009). The increase in the level of greenhouse gases in the atmosphere thus results in the rise of temperatures on earth. “Over the past 100 years, the average surface temperature has risen by about 0.7 Celsius degrees (1.3 Fahrenheit degrees)” (Schneider, 2009).
Greenhouse gases are either naturally produced or caused by human activities. Some kinds can be generated both by natural processes and by human production. Common forms of greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, ozone, and some types of synthetic chemicals.
Water vapor is by far the most abundant greenhouse gas. It largely reaches the atmosphere through evaporation from bodies of water like oceans, seas, rivers, and lakes. The extent of water vapor in the atmosphere is not fundamentally affected by people’s activities.
Carbon dioxide is the second most abundant greenhouse gas. It reaches the atmosphere through natural processes such as volcano eruptions, respiration of animals, and the burning or decay of plants and other organic matter. Humans nonetheless increase the amount of carbon dioxide in the atmosphere through the burning of fossil fuels (like coal, oil, and natural gas), solid wastes, and wood (and wood products) to heat buildings, propel vehicles, and generate electricity. Deforestation and widespread cutting of trees also indirectly cause carbon dioxide emissions as they reduce the number of trees that absorb carbon dioxide through photosynthesis.
Methane contributes to global warming about a third as much as carbon dioxide. It is released to the atmosphere through the mining of coal and the production of natural gas and oil. Rotting organic matter (in landfills, wetlands, and rice paddies), some animals (like cows), and live plants also emit some amounts of methane.
Nitrous oxide is emitted principally by burning fossil fuels and plowing farm soils. It is a potent greenhouse gas as it absorbs about 300 times more heat than does the same amount of carbon dioxide. This gas adds about a tenth as much as carbon dioxide to global warming.
Ozone in the lower atmosphere is a component of a hazardous form of air pollution called smog. The ozone in smog is formed by the combination of nitrogen oxides and volatile organic gases discharged by industrial sources and automobiles. As greenhouse gas, ozone contributes to global warming about a fourth as much as carbon dioxide.
Synthetic chemicals as greenhouse gasses have chemical bonds that make them remarkably long-lived in the environment. These include chlorofluorocarbons (CFCs), “a family of chlorine-containing gases that were widely used in the 20th century as refrigerants, aerosol spray propellants, and cleaning agents … New chemicals have been developed to replace CFCs, but they are also potent greenhouse gases. The substitutes include hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs)” (Mastrandrea, 2009). Sulfur hexafluoride, another synthetic chemical, is used in the manufacture and casting of magnesium and as insulation for high-voltage electrical apparatuses. It is “one of the most potentially destructive greenhouse gases ever produced … an exceptionally stable gas with an estimated lifespan of 3,200 years once it is released in the atmosphere” (Schneider, 2009).
Effects of Global Warming
Climate change and global warming do and will affect, among others, weather, glacial ice, sea levels, agriculture, plants and animals (wildlife), and even human life.
Weather patterns are projected to be less predictable. Probable effects of the global warming include more frequent extreme weather events including more intense and frequent heat waves, longer and more intense droughts, more severe storms and hurricanes, heavier rainfall, and denser snowfall.
Climate change causes substantial changes to the world’s mountain glaciers, the Arctic’s polar sea ice, and the Greenland and the Antarctic’s ice sheets. The extensive melting of ice may further accelerate the pace of global warming. Consequently, places will be generally warmer and more humid as a result of more water evaporating from the seas.
The sea level also rises as the atmosphere warms. When the surface layer of the ocean warms, it expands in volume and thus raises sea level. Melted glaciers and ice sheets will further swell the sea. This will complicate life in coastal regions and many islands as it will cause flooding and erosion of cliffs, beaches, and dunes.
Global warming may tremendously reduce agricultural production in some parts of the world. The rise in temperature and changes in precipitation patterns may damage food crops, ruining food production. For instance, some of Africa’s semiarid tropical farmlands may become all the more impoverished. Woodlands and crops may also be afflicted by more insects and plant diseases.
Climate change also affects wildlife as changes in the life cycles of many plants and animals are now observed. Many living organisms will also find it hard to escape from or adjust to the consequences of global warming. Animals will tend to migrate toward the poles and higher elevations and plants will attempt to shift their ranges. Species dwelling in unique ecosystems may just become extinct. Warmer ocean temperatures also cause widespread bleaching and death of coral reefs around the world. Likewise, growing carbon dioxide in the environment increases the acidity of ocean waters (acidification), thereby damaging the ocean ecosystems even more.
Effects relevant to humans include the loss of habitat from flooding and the threat to food security due to declining crop yields. More people begin to get sick or die from more frequent and intense heat wave and heat stress. Tropical diseases such as malaria, dengue fever, yellow fever, and encephalitis are anticipated to widen their range as mosquitoes and other animal hosts transfer to areas previously too cold for them. Cases of allergies and respiratory diseases will also rise as warmer air with pollutants, mold spores, and pollens grows more in the environment.
Ways to Address Global Warming
Controlling global warming demands radical changes in industry, energy production, transportation, development strategies, and government policies around the globe. It fundamentally requires reducing emissions of greenhouse gases, a strategy called ‘greenhouse gas mitigation.’ The following are some approaches to control or slow the buildup of greenhouse gases in the atmosphere:
1. Carbon sequestration
One major approach to slowing the accumulation of greenhouse gases is to keep carbon dioxide out of the atmosphere by depositing it or its carbon component somewhere else, a method known as carbon sequestration or carbon capture.
Carbon dioxide leaves the atmosphere when it is absorbed into water (such as seas and oceans). Trees and plants also take in carbon dioxide, convert it into simple sugars through photosynthesis, thereby storing carbon in new tissue. Therefore, one way to control the level of carbon dioxide in the atmosphere is to grow and preserve more plants, especially fast-growing trees.
Some companies also capture carbon dioxide directly and inject it into depleted oil wells to press more oil out of the seafloor or ground. “The same process can be used to store carbon dioxide released by a power plant, factory, or any large stationary source… Carbon capture would also involve transporting the gas in compressed form to suitable locations for underground storage” (Mastrandrea, 2009).
2. Reducing the consumption of fossil fuels
Reducing the consumption of fossil fuels directly reduces greenhouse gas emissions. This can be done by using fuels that release less heat-trapping gas and newer technologies for cleaner coal-burning power plants. In transportation, hybrid electric vehicles (HEVs), which use both an electric motor and a gasoline or diesel engine, release less carbon dioxide than usual automobiles.
But substantial decreases in carbon dioxide emissions can only be reached by switching away from fossil-fuel energy sources. Wind power, solar power, and hydrogen fuel cells can be good alternatives to fossil fuels as they emit no greenhouse gases. Other options are fuels made from plants, such as biodiesel (from vegetable oil) and ethanol (a plant-based gasoline additive). Some suggest the use of nuclear power plants which emit no carbon dioxide at all (but which is nonetheless controversial for some reasons such as safety and the high costs of nuclear waste disposal).
3. International Agreements
Cooperation among nations is also needed for the successful control of global warming. The first international conference addressing climate change was the United Nations Conference on Environment and Development, also called the Earth Summit, held in Rio de Janeiro, Brazil in 1992. There, the United Nations Framework Convention on Climate Change (UNFCCC) was signed by 150 countries, pledging to stabilize greenhouse gas concentrations in the atmosphere.
In December 1997 in Japan, 160 nations met and drafted a treaty called the Kyōto Protocol, amending the UNFCCC and setting mandatory targets for the reduction of greenhouse gas emissions. By 2006, 166 nations had signed and ratified the agreement, though remarkable exceptions included Australia and the United States. American president George W. Bush withdrew support for Kyōto Protocol in 2001, claiming that the treaty puts an unjust burden on industrialized nations and would harm the U.S. economy.
In March 2007, the European Union (EU) held a “green summit” to come up with a new international strategy to address global warming. The participating 27 nations of the EU reached a milestone accord that went above the Kyōto Protocol in establishing targets to lessen greenhouse gas emissions. Nonetheless, to really reduce such emissions in the years to come, much stronger and broader international agreements and actions are needed.
4. Cooperation by local governments, private enterprises, households, and individuals
The cooperation of local government units, private businesses, and every household are much needed to address global warming. In the U.S., for example, product manufacturers, local utilities, and retailers have worked together to implement the ‘Energy Star’ program, a strategy which rates appliances for energy use and gives some money back to consumers who purchase efficient equipment.
State and local governments may also help by establishing pertinent initiatives and implementing mandatory programs to limit emissions from the industries (such as power plants) within their respective jurisdictions. Households and individuals, too, can take measures to curtail their own emissions. Some steps include reducing pollution, buying energy-efficient appliances, using energy-saving light bulbs, adding insulation to a house, recycling materials, opting to live near work, and walking or commuting by public transportation (instead of using one’s automobile).
All of the approaches discussed above center on mitigation by reducing emissions. Other possible responses to global warming may also include adaptation to its effects, constructing systems resilient to its effects, and future climate engineering. (© 2013 by Jensen DG. Mañebog)
Climate Change: Causes, Effects, and Solutions, © 2013 by Jensen DG. Mañebog