Natural climate changes are those that occur organically, devoid of human contribution. Anthropogenic climate changes occur as a result of human activity (WMO, n.d). Climate is affected by natural changes that have an effect on how much solar energy gets to the earth. These changes occur in the sun and the earth’s orbit. The changes that take place in the sun have an effect on the intensity of sunlight that reaches the earth’s surface. The concentration of solar energy may cause either warming during periods of great solar intensity or cooling, when the solar intensity is weak. While the sun adheres to a normal eleven-year cycle with negligible shifts in intensity, its effect on the earth’s climate is minimal (EPA, 2014).
The earth’s orbit changes from time to time in the shape and position on its axis, which affects the quantity of sunlight that reaches the earth. An example of a change in climate caused by a change in the sun’s intensity is the ‘Little Ice Age’ that occurred between the 17th and 19th centuries (EPA, 2014). It resulted in the cooling of Europe, North America and other areas north of the earth. It was characterized by a slight solar inactivity that happened concurrently with cooler seasons of the year. The intensity of summer sunshine in the Northern Hemispheres is influenced by shifts in the earth’s orbit. It in turn directs the progression and draw-back of ice sheets (EPA, 2014).
Human industrial and agricultural activities cause the emission of greenhouse gases. The earth characteristically responds to certain gases in the atmosphere. These gases cause the sunlight to enter the atmosphere and absorb heat radiation. These gases absorb the heat to keep the earth’s surface temperature at approximately 14º as opposes to around -19º (WMO, n.d).
Carbon dioxide is a greenhouse gas produced due to deforestation and combustion of fossil fuels. Since the industrial revolution, the carbon dioxide concentration in the atmosphere has increased by 30%. Methane is released from landfills and agriculture. Nitrous oxide is produced by the manufacture and use of macrobiotic fertilizers and when burning fossil fuels. Chlorofluorocarbons are artificial compounds created for industrial purposes such as air conditioning. It affects the ozone layer by making it less efficient in protecting against harmful sun rays (WMO, n.d).
Global Warming is taking place
The earth’s average temperature is one reliable indicator of global warming and is one of the most referred to facts. The global temperature has gone up by approximately 1.4ºF from early 20th century (NCDC, 2010). Surface temperature is pegged on sea-surface temperature monitored from satellites and ships and air temperature over land. The Northern Hemisphere snow cover has been on the steady decline in current decades. The most significant reductions have been recorded in the summer and spring seasons (Nordhaus & Boyer, 2003).
Warming temperatures have caused ice sheets and glaciers to melt considerably. The overall quantity of glaciers on the earth is reducing stridently (Nordhaus & Boyer, 2003). Glaciers have been melting globally in the last century, which accounts for rising sea levels around the world (NCDC, 2010). There have also been increased occurrences of extreme weather events such as hurricanes and storms, and inconsistent weather patterns (NCDC, 2010).
Current mitigation strategies for global warming
In order to mitigate global warming, efforts have been made towards better energy supply and allocation efficiency (IPCC, 2007). There have been campaigns to change from coal to gas consumption and renewable energy like wind, solar, hydropower and bio-energy. The policy towards ensuring increased renewable energy consumption is reducing fossil fuel subsidies in order to minimize the amount of greenhouse gases released into the atmosphere as a result of burning fossil fuel. It also includes a tax or charges on fossil fuels (IPCC, 2007). The implementation process may face opposition from parties with vested interests in fossil fuels such as the suppliers. When it comes to costs, factors such as the price of fuel, wholesale rates and demand for energy may pose a challenge in computing the impact of renewable energy authorization on electricity charges (IPCC, 2007).
Another mitigation strategy is increasing forest cover through afforestation and reforestation. Policies include forest management and financial inducements to encourage the increase of forest cover (IPCC, 2007). There is the regulation of the production and use of forestry products. Limited investment capital into increased forest cover efforts and land tenure issues may challenge its implementation process. The advantage of the incentive is that it may minimize poverty through compensation to individuals that plant trees on their land. Afforestation costs are variable depending on the type of land and the geographical area (IPCC, 2007). The costs of forest cover improvement increase when the opportunity cost of land is considered. Primary investments towards afforestation can be a challenge as it would take a long time to realize the return on investment, about a decade or more (IPCC, 2007).
Policy changes to help stabilize global climate change
The policy changes that I would propose would be the ban on the manufacture and use of plastic bags. The process of producing plastic bags emits greenhouse gases into the atmosphere that increase the overall earth surface temperature. In addition, the product causes more harm to the environment when it is inappropriately disposed of and finds its way into water bodies. The industries and businesses that I would be strict on in this respect is retail businesses that use plastic bags for packaging, as they are the largest customer base for plastic bag manufacturing companies. I believe this strategy would go a long way in helping mitigate global warming.
- Environmental Protection Agency. (2014). Causes of Climate Change. Retrieved 6th Mar from http://www.epa.gov/climatechange/science/causes.html
- Intergovernmental Panel on Climate Change. (2007). Adaptation and Mitigation Options. Retrieved 6th Mar from http://www.ipcc.ch/publications_and_data/ar4/syr/en/spms4.html
- National Climatic Data Center. (2010). Global Climate Change Indicators. Retrieved 6th Mar from http://www.ncdc.noaa.gov/indicators/
- Nordhaus, W. D., & Boyer, J. (2003). Warming the world: Economic models of global warming. Cambridge, MA: MIT Press.
- World Meteorological Organization. (n.d). Causes of Climate Change. Retrieved 6th Mar from http://www.wmo.int/pages/themes/climate/causes_of_climate_change.php