Greenhouse gases are chemical compounds that contribute to the greenhouse effect by allowing solar radiation to enter the earth’s atmosphere where it warms the earth’s surface and is reradiated back into the atmosphere as longer wave heat energy. These gases absorb this heat and trap it in the lower atmosphere (Reay, 2008). This phenomenon has had adverse effects on the global climate which in turn directly effects the human population.
The U. S.being the third most populous country in the world and having a diverse geography encompassing a wide range of tropical, arctic and temperate ecosystems is among the countries that experience the first hand effects of greenhouse gas emissions (Hopwood & Cohen, 2009). It is no wonder that Americans at all levels are taking measures to address the grave challenge posed by climate change to promote a sustainable emission free future. The objective of this paper is to identify and critically analyze the major greenhouse gases with an aim of elaborating how they affect human development in the U.
S. and the steps that are being taken to mitigate these effects. This will be achieved by consulting high level scholarly journal articles and scientific reports that will enable an excellent and informed scope of the matter at hand. The U. S. Greenhouse Gas Inventory will be of great help to this paper as it documents the emission trends over the years. The paper will elaborate the widespread negative influence that these gases have on the U. S. population. INTRODUCTION This paper is divided into two sections.
The first section gives a step by step analysis of each of the major greenhouse gases by identifying the sources, behaviors and its influences on the human population. The second section will give an integrated outlook on the overall impacts of the greenhouse gases across a wide section of factors including; economical, health, social, environmental factors among others. It will then shift focus into the mitigation measure that are put in place in efforts to mitigate the effects of the greenhouse gases on the human population in the U. S.
Finally, it will give an analysis of the future prospects on the trends of greenhouse gas emissions and how they will affect the future. SECTION 1: ANALYSIS OF THE MAJOR GREENHOUSE GASES IN THE U. S Source: umich. edu The above graph shows the most prominent greenhouse gases in the earth’s atmosphere by percentage. The next section will evaluate each one of them. CARBON DIOXIDE Carbon dioxide is the most prominent greenhouse gas in the Earth’s atmosphere. It is colorless, odorless and non flammable. It is very important in various processes that make life on earth possible
Sources of carbon dioxide The main source of carbon dioxide emission is the burning of fossil fuels i. e. natural gas, coal and oil for production of energy. This comes from industries, automobiles and other energy intensive systems. Carbon dioxide circulates in the atmosphere through the carbon cycle by the processes of photosynthesis and transpiration by living organisms. Photosynthesis traps light energy and uses it to convert carbon dioxide, water, and other minerals into oxygen and energy rich organic compounds.
This makes forests and wooded areas to act as natural sinks of CO2 hence deforestation is another major producer of this gas i. e. as the abundance of trees declines, less carbon dioxide can be recycled. Carbon dioxide is emitted into the air as humans and other animals exhale. These processes combined add over 30 billion tones of CO2 into the atmosphere annually (Energy Information Administration, 2004). Effects of carbon dioxide Excess amounts of carbon dioxide in the atmosphere in recent years have had widespread effects on the environment in the U. S.
The most obvious and widespread effect is global warming since this gas makes up the largest portion of all the greenhouse gases. This has seen the American population experience steady rise of temperature over the years. Carbon dioxide is essential in plant growth for the process of respiration from which plants make food. Raised atmospheric carbon dioxide can have both positive and negative effects on plant growth. The U. S is a major producer of wheat and maize. Scientific findings have shown that these crops could experience an increase in yield by a significant percent.
This is due to the increased photosynthetic rate that is derived from raised carbon dioxide levels. However, a look at the whole farming system reveals that these benefits are likely to be much lower than usually estimated. This is after putting into consideration factors associated with climate change such as increased frequency of extreme weather events, season shifts and so on (Spencer, 2005). Too much carbon dioxide can also have negative effects on human health. The gas plays a vital role in regulation of blood pH through the body’s buffer system called the carbonate buffer.
When carbon dioxide concentrations increase or decrease, it disrupts this equilibrium which might result to kidney failure or a coma. Another health problem caused by carbon dioxide if frostbite. Solid CO2 is always below -780 and handling it would result into serious blisters and other undesirable effects. At high levels, the gas can cause headaches, dizziness and nausea. If exposure is extended, it could result into asphyxiation as it replaces oxygen in the blood (Kasting, 2002).
This levels are however rare in normal circumstances but only found in situations of overcrowded areas, buildings with poor ventilation or places with artificial production of the gas. Carbon dioxide poisoning is therefore rare. METHANE Methane is a colorless odorless gas which a major component of natural gas. It is over 20 times more effective in trapping heat in the atmosphere than carbon dioxide and remains in the atmosphere for a period of 9-15 years. It accounts fro about 13% of global greenhouse gas emissions (Hopwood & Cohen, 2009). Sources of methane
Methane is emitted by a variety of both human and natural sources. Human sources account for about 60% of total methane emitted in the U. S. Human activities that add methane to the atmosphere include agricultural activities such as rice cultivation which has developed into a large business feeding a third of the world’s population. Methane is formed by bacterial breakdown when these plants decay and where there is very little air. Livestock such as cows, sheep, goats, camels, buffaloes, and termites contribute to emission of methane as well.
Bacteria in the gut of these animals break down food and convert some of it to methane which is released when these animals belch (Hopwood & Cohen, 2009). The U. S has vast ranches with these animas that release several million tones of methane per day. Land filling is another human activity that contributes to emission of methane. Bacteria break down waste in land fills into other products and methane which escapes into the atmosphere. Other human sources of emission include coal mining, natural gas and oil systems. Natural sources of methane include; wetlands, gas hydrates and permafrost.
Effects of methane Methane is a far more effective green house gas than carbon dioxide. It traps about 20 times more heat energy than carbon dioxide. Scientific research has shown that methane might be contributing to global warming much more than carbon dioxide despite its lower proportion in the atmosphere. Methane gas also has negative health effects on humans if there is prolonged exposure caused by large releases of the gas. Common symptoms of methane gas poisoning include dizziness, headaches, nausea, drowsiness and unconsciousness.
Methane gas poisoning can lead to hydrogen sulfide poisoning, asphyxiation, explosion and fire, according to the Wisconsin Department of Health Services (Hopwood & Cohen, 2009). NITROUS OXIDE Like the other two gases nitrous oxide is a colorless gas but it has a sweet smell. It is primarily used as an aesthetic as it deadens pain. Recently the levels of nitrous oxide in the atmosphere have been on the rise and it is the third most important greenhouse gas. Sources of nitrous oxide Nitrous oxide is produced into the atmosphere through a variety of human and natural factors.
Agricultural practices are a major source of this gas. Microbial processes of nitrification and denitrification produce nitrous oxide. Agricultural practices and activities that increase these emissions include; “the use of synthetic and organic fertilizer, production of nitrogen fixing crops, cultivation of high organic content soils and the application of livestock manure to croplands and pasture” (U. S. Environmental protection Agency, 2010). All these practices add nitrogen to the soil which is then converted to nitrous oxide. Livestock manure management contributes to the emission of nitrous oxide.
The organic nitrogen present in livestock manure undergoes a cycle of nitrification and denitrification which eventually yields nitrous oxide. This will depend on the type of bacteria present in the manure and the amount of oxygen and liquid in the composition. Nitrous oxide emitted in the United States through livestock manure related processes is significant considering the large number of livestock in the country (Energy Information Administration, 2004). This gas is also produced during fossil fuel combustion where there is the direct reaction between oxygen and nitrogen.
This occurs in motor vehicles and other devices that burn these fuels. The level of emission depends on the technology employed in the device to reduce pollution levels e. g. catalytic converters in recent vehicle models address this problem. The U. S Greenhouse Gas Inventory Report has documented a significant amount of nitrous oxide that is emitted from the management of human sewage. Domestic sewage is mixed with other household wastewater that contains nitrogen in the form of urea, ammonia and proteins. These materials undergo anaerobic processes that eventually yield nitrous oxide that escapes into the atmosphere.
Effects of nitrous oxide According to a new study, nitrous oxide has now become the largest ozone depleting substance emitted through human activities and it is expected to remain so throughout the 21st century (National Oceanic and Atmospheric Administration, 2009). Nitrous oxide has surpassed chlorofluorocarbons as the lead ozone depleting greenhouse gas. Chlorofluorocarbons have mostly been phased out through regulatory efforts. This deterioration of the ozone exposes the human population to harmful ultraviolet rays from the sun which leads to increased cases of skin cancer.
Plants are also affected genetically leading to mutations (Hopwood & Cohen, 2009). On the environment, nitrous oxide in the ground level causes smog which is a nuisance especially for motorists as it combines with particles to reduce visibility. It contributes to acid rain which has direct impacts on farming. Acid rain also reduces the lifespan of metallic structures creating a burden to developers. The gas leads to oxygen depletion in water bodies upsetting chemical balance in aquatic environments by creating acid water bodies. The gas also has direct health effects on people.
It causes respiratory problems such as asthma, emphysema and bronchitis. It aggravates existing heart disease and exposure to high its high amounts causes damage to the lungs. Their overall health effect on the American population is a declining life expectancy (Yamaguchi, Soejima, Koda & Sugiyama, 2001). FLOUROCARBONS Fluorocarbons are synthetic organic compounds that contain fluorine and hydrogen. The major types are chlorofluorocarbons, CFCs (containing chlorine) and hydroflourocarbons. Sources of fluorocarbons They are mainly used in aerosol cans.
This is because they can be easily converted from gas to liquid or from gas to liquid making them suitable for refrigerator and air conditioners. These appliances release these gases into the atmosphere. CFCs break down to release chlorine in the atmosphere. Effects of fluorocarbons The chlorine in CFCs breaks down molecules in the earth’s ozone layer. Deteriorating ozone admits harmful ultraviolet rays into earth which has adverse effects on people and the ecosystem as discussed in the previous section under nitrous oxide. The use of CFCs has however been banned but the amounts emitted before the ban have continued affecting the U.
S. population. HFCS on the other hand do not affect the ozone but they contribute to the greenhouse effect. Other gases in these category are perflourocarbons (PFCs) and sulfur hexafluoride. In addition to having high global warming potential, these two have long atmospheric lifetimes hence their effects on the environment are practically irreversible (Holleman & Wiberg, 2001). SECTION 2: IMPACT OF GHGs EMMISIONS AND MITIGATION EFORTS This section takes an integrated approach to the effects that greenhouse gases have on the American population. The U. S.
Environmental Protection Agency recognized the effects of greenhouse gases on the environment, calling them a threat to public health and the environment. These threats cut across a variety of human development area as elaborated below. GLOBAL WARMING As elaborated before, greenhouse gas emission causes global warming. Global warming in turn has adverse effects on the environment and human life in numerous and varied ways. The different ways in which global warming affects the American population are identified in the next section. Melting of polar ice caps
The melting of polar ice caps due to global warming has its associated dangers in the U. S. Firstly, it will raise sea levels. According to the National Snow and Ice Data Center, there are more that 5,773,000 cubic mile of water in ice caps, glaciers and permanent snow (Sharma, 2008). The melting of such an amount of water would seriously affect areas like the Manhattan District of New York City which could easily be rendered uninhabitable. The global ecosystem could easily be thrown out of balance by this phenomenon. The water from the polar ice caps is fresh water and it would therefore desalinate the seas in the U.
S. Desalinization distorts ocean currents which regulate temperatures. This would result into changed and irregular weather patterns of cooling and warming effects in the coastal areas of the U. S. several species would be directly affected by the change in the aquatic salinity which could adversely affect the fishing industry, a source of livelihood for a section of the American population (Sharma, 2008). Heat waves The increase in Earth’s average temperature has resulted in changes in the weather patterns that are manifested in different ways. In the U. S, there has been an increase of incidences of heat waves.
According to Spencer, during the summer of 1998, there was a deadly heat wave in Texas where temperatures in Dallas were over 37. 80 for 15 straight days. The heat wave claimed more than 100 lives. In 1999, more than 250 people died as a result of a heat wave that gripped much of the eastern two-thirds of the country. Heat indices of over 1000F (37. 80C) were common across the southern and central plains, reaching a record 1190F (48. 30C) in Chicago (Spencer, 2005). This adverse effect will continue to affect the lives of the American population as temperature changes assume an upward trend.
Drought A study released by the Lamont-Doherty Earth Observatory indicates that global warming related climate change is “likely to lead to long periods of extreme drought throughout the American Southwest starting early this century. ” The arid area of southwestern North America will become even more arid. This poses a big threat to the increasing population in these areas driving up the demand for water that is mainly used for agriculture (Spencer, 2005). People in these areas will be forced to spend more money in conservancy and efficiency efforts if they are to survive the looming crisis.
The study compares the coming drought to the drought in 1930s that sent millions of environmental refugees to California from these regions. “The period from April-July 1999 was the driest in 105 years of record-keeping in New Jersey, Delaware, Maryland, and Rhode Island. Agricultural disaster areas were declared in fifteen states, with losses in West Virginia alone expected to exceed $80 million” (Spencer, 2005). These changes are directly attributed to the overall surface drying driven by rising greenhouse gases. Ocean warming and hurricanes Hurricanes are a natural phenomena caused by a diverse number of factors.
Global warming does not cause hurricanes but it does make them stronger and more dangerous. As the oceans get warmer, warm water and warm air interact to give tropical storms energizing them and making them, more powerful. Hence a hurricane could be turned from say category 3 to a more dangerous category 4 storm. Scientists have linked increased destruction of recent hurricanes like hurricane Katrina to increased ocean warming. Global warming will therefore continue affecting the American population in this way as ocean temperatures continue rising (Sharma, 2008).
Snowstorms Strange as it may seem, global warming is contributing to harsh winters in the U. S. warm conditions causes more water to be evaporated from the oceans and thus creating more moisture for winter storms when temperatures remain below freezing point. Evidence pointing to this is for example found in Washington D. C which has experienced three feet snowfalls in one winter. Such an event has a once in a 400 year rarity showing how adverse the effect of global warming is to the climate changes. In 1998, the Black Hills in South Dakota received record snowfall of 102.
4 inches in five days which is almost twice as much snow fall compared to the previous snow record of the state (U. S. Environmental protection Agency, 2010). Wildfires Scientists have linked the increased forest fires in the U. S to the changing weather patterns. Warm springs and early summer translates into reduced snowmelt and a longer season in which fire can be started. Statistics from research shows that the wildfire season has extended by 7 days in the recent past. Wildfires results into a diminishing forest cover.
This is particularly worrying since forests act as natural sinks to majority of the greenhouse gases produced in the U. S. The scenario unfolds in a domino effect manner which multiplies the negative effects on the population (Barbalace, 2006). ACID RAIN Acid rain is caused by emission of sulfur dioxide and nitrogen oxides from power plants, cars and factories that burn fossil fuels. There are natural source of these gases such as volcanoes, forest fires and lightning strikes. These gases are swept up in air and taken up into the higher levels of the atmosphere where they interact with water vapor resulting into sulfuric and nitric acids.
These acids fall onto the earth’s surface as rain, snow, sleet or fog precipitation (Spencer, 2005). Acid rain has negative effects on plants. It dissolves helpful minerals like calcium, magnesium and potassium making plants suffer deficiency. Forests in the U. S have slowly over the years experienced stunted growth through years of soil degradation. Such effects have negatively influenced the U. S. Agricultural sector which has at times experienced low yields. Acid rain has effects on materials and finishes. It has the ability to corrode and obliterate the most durable material like stone and metal.
It affects buildings, monuments and other structure in a way that speeds up the natural weathering caused by rain, the sun, snow and wind. Americans have continued feeling the effects of acid rain as it destroys automotive paint which can only be remedied by repainting. It also has negative health effects as it reacts with volatile organic compounds to form ground level ozone which aggravates and weakens the respiratory system. The sulfate and nitrate components of acid rain can cause asthma, bronchitis and heart problems (Yamaguchi, Soejima, Koda & Sugiyama, 2001).
DISEASE SPREAD Disease spread is accelerated by climate change because warmer temperatures broaden the range over which disease causing microorganisms, insects and animals can survive. For example dangue fever has been reported in areas of attitude higher than 3,300 feet which was unheard of in the former years. This is due to the fact that temperatures in these areas have increased to levels where mosquitoes can thrive. The concept of global warming and disease can best be illustrated by the events of the 1999 summer when 62 cases of West Nile virus were reported in New York.
Dr. Dickson Despommier explained that the disease was spread by one species of mosquito which resorted to biting humans when its normal bird target flew away to escape the heat wave (Sharma, 2008). High temperatures also trigger increased mosquito biting frequency. As the world warms up, an example of another disease that is likely to spread quickly is Bird Flu. Global warming is resulting to excessive loss of wetlands which affects the trends of disease carrying migrating birds. These birds would normally have their stopping points in wetlands but instead land on animal farms.
Here they interact with domestic poultry and other animals aggravating the spread of the disease through animal-human and human-human contact. Scientific predictions indicate that global warming will cause an increase of incidences of malaria dengue fever, yellow fever, encephalitis, and respiratory diseases throughout the U. S. in the coming decades (Yamaguchi, Soejima, Koda & Sugiyama, 2001). ECONOMIC IMPACT The economic sector that is not affected by global warming is the agricultural sector. This is because of the serious disruptions on weather patterns explained in the previous sections.
With this influences, agriculture is impossible. It can only be done through highly expensive interventions that would come at a very heavy cost to the world economy. According to Spencer, scientists measured the annual yields of the world’s six largest crops over the past twenty years and found that increasingly warmer temperatures lad to lower crop yields. These lower crops amounted to a net economic loss of 5 billion dollars a year (Spencer, 2005). Apart from such costs, the world economy will suffer from the damages that are as a direct result of global warming.
Such damages include; damages from severe hurricanes, snowfalls, acid rain, heat waves and flooding. Each of these disasters causes widespread damage to the environment and man made structures that require massive finances to repair. They also result into loss of lives which translates into lost revenue that this people would earn. The effects of climate change from greenhouse gas emissions will be so serious that 1%of global gross domestic product would be required to mitigate these effects. Efforts to reduce carbon dioxide emissions by 50% have been estimated to cost the economy 45 trillion U.
S dollars over the next 40 years. The energy sector is the largest contributor to greenhouse gas emissions. Using clean energy would affect a family of four as follows: “energy costs go up $436 that year, and they eventually reach $1,241 in 2035 and average $829 annually over that span. Electricity costs go up 90% by 2035, gasoline by 58%, and natural gas by 55% by 2035. The cumulative higher energy costs for a family of four by then will be nearly $20,000” (Kasting, 2002). This is just at the household level. Every commodity would go up as the increased energy cost drives up cost of production.
Estimating the economic impact of global warming is not easy but it is clear that it has immense costs at all levels. MITIGATION EFFORTS Policy: there have been international efforts to make and implement laws that will cap greenhouse gas emissions at certain levels. One of such efforts is the Kyoto protocol where governments from all over the world commit themselves to cutting down emissions to specified levels. Countries like the U. S. under this agreement can make tradeoffs with countries that have extra permits.
This are measures to put the emissions of greenhouse gases in check. Other policies prohibit the production of some greenhouse gases like CFCs and encourage the use of substitutes that are less harmful to the environment (Sharma, 2008). Clean energy sources: These are energy source that emit little or no greenhouse gases. Such include hydropower that uses hydraulic turbines with the force of rushing water. This is the most clean and cheapest way of energy production. Wind power is another renewable energy source. Countries like Denmark are the leading wind power producers.
Challenges in the use of wind power include the large amounts of land that it takes and there is need to develop better power storage techniques for it to be more effective. Another concern is noise pollution that the large windmills produce (Holleman & Wiberg, 2001). Individual choices: Recently there have been increased efforts by people to adopt practices and choices that have minimal or no contribution to the emission of greenhouse gases. This has seen people become increasingly critical on how commodities are produced and the materials used in their production.
This can be illustrated by the fact that most companies are “going green” i. e. using renewable and clean energy sources to entice consumers. This is due to the increased awareness on the benefits of minimizing or eliminating the use fossil fuels that contribute to green house emissions. CONCLUSIONS The impacts of increased greenhouse emissions on the American population are adverse and widespread. The greenhouse effect that causes global warming is particularly worrying phenomena that has brought drastic climate changes that have adverse effects on the human population.
There has been increased awareness on this effects which have led to the adoption of measures to mitigate the harmful effects. The future of greenhouse gas emissions and their effects looks uncertain.
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