Global Warming Essay

Global warming and Livestock

Earth's atmosphere contains certain gases called greenhouse gases (mostly water vapor and carbon dioxide) which act to keep the lower layers of the atmosphere warmer that they otherwise would be without those gases. “Global Warming” is the expected slow, gradual warming of the lower layers of the Earth’s lower atmosphere by the slowly increasing concentrations of man-made greenhouse gases, primarily carbon dioxide, and to a lesser extent methane. These gases trap infrared radiation, which is the “heat radiation” that cools the Earth. (In order for the Earth to remain at a constant temperature, the Earth must lose as much energy through infrared radiation as it gains from the sun. This concept is called energy balance.) The burning of fossil fuels, mainly petroleum and coal, produces carbon dioxide as one of the by-products. As of 2003, the concentration of carbon dioxide is over 50% higher than it was before the start of the industrial revolution in the late 1800's-which is when the burning of fossil fuels really took off. (Herro, 2008)

Global warming is a very serious issue. The consensus of opinion is that a warming of about 0.2 degrees Celsius (about 0.4 deg. F) every 10 years is expected for the next 100 years or so. This can lead to disastrous consequences. Increasing global temperatures are causing a broad range of changes. Sea levels are rising due to thermal expansion of the ocean, in addition to melting of land ice. Amounts and patterns of precipitation are changing. The total annual power of hurricanes has already increased markedly since 1975 because their average intensity and average duration have increased (in addition, there has been a high correlation of hurricane power with tropical sea-surface temperature). (Jacobson, 2007)

Changes in temperature and precipitation patterns increase the frequency, duration, and intensity of other extreme weather events, such as floods, droughts, heat waves, and tornadoes. Other effects of global warming include higher or lower agricultural yields, further glacial retreat, reduced summer stream flows, species extinctions. As a further effect of global warming, diseases like malaria are returning into areas where they have been extinguished earlier. Although global warming is affecting the number and magnitude of these events, it is difficult to connect specific events to global warming. Although most studies focus on the period up to 2100, warming is expected to continue past then because carbon dioxide (chemical symbol CO2) has an estimated atmospheric lifetime of 50 to 200 years. (Winter, 2007)

A single contirubutor to global warming cannot be pinpointted. Numerous factors play a vitral role in giving immense rise to global warming in today’s world. Carbondioxide emulsion from factories, cars, buildings, powerplants, and vehicle raises global warming. Besides carobondioxide, gases like methane and nitrousoxide also serve as the unfriendly gases in the atmosphere. Deforestation and livestock also contribute to global warming.

The harmful environmental effects of livestock production are becoming increasingly serious at all levels—local, regional, national and global—and urgently need to be addressed. Extensive livestock production plays a critical role in land degradation, climate change, water and biodiversity loss. grazing occupies 26 percent of the Earth's terrestrial surface, and feed-crop production requires about a third of all arable land. Expansion of livestock grazing land is also a leading cause of deforestation, especially in Latin America. In the Amazon basin alone, about 70 percent of previously forested land is used as pasture, while feed crops cover a large part of the remainder. We are seeing land once farmed locally being transformed to cropland for industrialized feed production, with grasslands and tropical forests being destroyed in these land use changes, with resources feeding livestock rather than the humans who previously depended on those lands. (Whittelsey, 2007)

When emissions from land use are factored in, the livestock sector accounts for 9 percent of all carbon dioxide emissions derived from human-related activities, as well as 37 percent of methane emissions—primarily gas from the digestive system of cattle and other domesticated ruminants—and 65 percent of nitrous oxide gases, mostly from manure. (Netting, 2005) The problems surrounding livestock production cannot be considered in isolation, nor are they limited to the environmental impact, noting that economic, social, health and environmental perspectives will be critical to solving some of these problems. We hope to develop a greater understanding of these complex issues so that we may encourage policies and practices to reduce the adverse effects of livestock production, while ensuring that humans are fed and natural resources are preserved, today and in the future.


References
Herro, Alana. Adjustments to Agriculture May Help Mitigate Global Warming. World Watch, May/Jun2008, Vol. 21 Issue 3, p4-4, 1/2p

Winter, Drew. Livestock are the Real Climate Pigs. Ward's Auto World, Nov2007, Vol. 43 Issue 11, p3-3

Whittelsey, Frances Cerra. BIO-HOPE, BIO-HYPE. Sierra, Sep/Oct2007, Vol. 92 Issue 5, p50-51

Jacobson, Michael F. Diet for a Cooler Planet. . Nutrition Action Health Letter, May2007, Vol. 34 Issue 4, p2-2

Netting, Jessa Forte. Littlest Butterfly. Discover, Dec2005, Vol. 26 Issue 12, p9-9

Source http://www.easydissertationhelp.com