Global Warming and Western United States Wildfires
Larger fires have occurred more frequently in the Western United States of America as the spring temperatures come earlier and the summer temperatures gets hotter. The purpose of this paper is to conduct a study that will provide data showing the link between climate driven fires and the increase in temperature due to global warming. Scientifically backed evidence indicates that the growth in wildfires is linked to global warming. In order to provide a factually backed argument the study will seek to answer a number of questions that includes; Are wildfires considered a natural disaster or are they a product of man made disasters?
How do the yearly snowmelts affect seasonal wildfires? Data observation of seasonal temperature changes, what is the scientific link between changing and the frequency and intensity of wildfires? What are the significant changes that make conditions favorable for wildfires? What models of predictions exist that causes conditions for wildfires? What are the economical losses due to the wildfires? How has the wildfires affected the environment and are there a negative or a positive effect on the ecosystems? Refined Hypothesis Wildfires may be caused by both manmade and natural factors.
For instance, man can accidentally start a fire by unknowingly throwing flammable objects on dead and dry trees and shrubs, the work of arsonists is also another manmade activity. On the other hand natural factors such as lightening and global warming have been noted to contribute immensely in the increase of the frequency of wildfires. For purposes of this paper’s research study scope, a narrowed down approach will be adopted: global warming will be discussed as the main factor behind the frequent wildfires in the Western United States of America.
Sufficient evidence shows that, global warming that brings about extreme climatic changes is the cause for wildfires that have been on the increase in the Western region of the United States. According to Running, (2006), the escalation of wildfire activity in the western United States is directly linked to the increase in temperatures (global warming). He contends that “Higher temperatures and earlier snowmelts are extending the wildfire season and increasing the intensity of wildfires in the Western United States.
” (pp. 927-928) Reasons Natural hazards cause hundreds of deaths and cost billions in disaster aid, disruption of commerce and trade, destruction of homes and critical infrastructure. Wildfires are an example of such growing natural hazards that poses a threat to life and property. Despite themselves causing numerous deaths and loss of property directly, they are indirectly equally disastrous, in that, they increase the potential for flooding and landslides.
The smoke and other gaseous emissions that emanate from wildfires contain pollutants that can cause significant health problems. The more the emission of greenhouse gases into the atmosphere the more the increase of the risk of wildfires occurrences. Causal Relationships Running (2006), analyzed the most comprehensive data set of wildfire occurrences compiled for the Western region of the United States, he analyzed on the lines of geographical location, seasonal timing, and regional climatology of the 1166 recorded wildfires with the extend of more than 400 ha.
His findings were that the length of the active wildfire season increased by 78 days and the average burn duration of large fires has increased fro 7. 5 to 37. 1 days. (pp. 927-928) Fire activity is strongly influenced by four factors; they are weather, climate, fuels, and ignition agents. Climate and weather are dynamic, for instance our climate and weather experiences constant warming due to increase in radioactively active gases.
The causal relationship between global warming hazards and wildfires is dynamic in nature as it is subject to global environmental change. The global significances of environmental change are the two major environmental problems of depletion of the ozone layer and climate change. Westerling et al (2006) studied wildfire trends in the Western United States and compared it with hydro-climatic and land-surface data; they used data collected over a long period of time (thirty five years) for 1,166 wildfires between 1970 and 2003.
They found out that large wildfire activity increased suddenly (four-fold margin) and markedly in the mid-1980s. This duration was characterized by large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. Much of this increase was witnessed in the mid-elevation Northern Rockies forests, whereby there is very minimal land use and therefore little risks of fires, this was an indicator that the increase in spring and summer temperatures is responsible for such fires.
In their findings they indicated that temperatures affects summer draught, and thus the flammability of live and dead fuels in forests through its effect on evapo-transpiration and, at higher elevations, on snow. According to them, an earlier snowmelt can lead to an earlier, longer dry season, providing greater opportunities for large fires due both to the longer period in which ignitions could potentially occur, and hence increased incidence of wildfires. Forests in the western region of the US are more vulnerable to wildfires due to warmer temperatures during spring and summer seasons.
In what seems to be a departure from various studies carried out to investigate the relationships between climate change and wildfires, Marlon et al (2009) carried out a research study that investigated the effects of abrupt climate changes and heightened fire activity in the paleorecord. They used thirty five charcoal and pollen records to assess ho fire regimes in North America changed during the last glacial-interglacial transition (15 to 10 ka). Their study showed that biomass burning gradually increased from glacial period to the beginning and also after the younger Dryas.
They found out that rapid climate change is a key factor in determining broad-scale levels of fire activity in the forests. For instance, intervals of rapid climate change at 13. 9, 13. 2, and 11. 7 ka were marked by large increases in fire activity. Their study findings refuted earlier assertions that a comet impact initiated continental-scale wildfires at 12. 9ka, and that continent-wide fires were never experienced at any time during de-glaciations period.
Kitzberger, Brown, Heyerdahl, Swentnam and Veblen (2007) carried out a research study using fire scarred trees in nine regions in western North America that were noted to experience a higher frequency of wildfires. Links between contingencies of El Nino Southern Oscillation and Pacific Decadal Oscillation, droughts and wildfires have been noted in the western U. S. before. The use of 20th Century data half the variance in fire occurrence among the nine sub regions in their study was explained by components from a rotated principle components analysis of the annual percentage of sites recording fires.
In their findings they contend that due to El Nino events there are earlier snowmelts which have an impact on the longer fire seasons. In their study methodology they assessed fire synchrony based on two procedures by identifying the years and a statistical comparison of observed and expected numbers of synchronous. They concluded that there are eight different climate drivers that can factor the connection between wildfires and climate changes. Tolme’s (2004) work was the first of its kind to give a clear picture of the effects of global warming on wildfire intensity in a particular part of the country.
In his findings he states that despite what may have earlier thought about the occurrence of wildfires, there is a higher possibility of catastrophic fires becoming more common due to global warming. He asserted that “Warmer, drier and windier weather promotes wildfires, and these are all conditions that will result from climate change”. His research also reveals that the effects of financial and geophysical climate because of the results of the drier climate caused by global warming.
In another study carried out by Field, Torn, & Mills (2004), a link was made on general Circulation Model Output to local weather and fire records and projecting fire outcomes with an initial attack Suppression Model. In their findings they state that the paleo record and historical data that shows changes in wildfire frequency are closely linked to climate. Climate change has the potential to affect multiple elements of the wild land fire system, fire behavior, ignitions, fire management, and vegetation fuels.
The study estimates the likely impacts of climate change using a geographically explicit model that estimates fire behaviors. More than half of the most damaging fires occurred in California. Definition of Variables Global warming is the increase in the average temperatures of the earth near-surface air and the oceans since the mid-twentieth century and its projected continuation. It is believed that the major cause of global warming is the excess emission of greenhouse gases into the atmosphere. This causes the depletion of the ozone layer which protects the excess penetration of strong radiations from the sun.
A slight increase in global temperatures can cause ice sheets to melt, rivers to dry, deserts to encroach, trees to dry and shed leaves, and other forms of desert like situations. There exists sufficient researched evidence that indicates that these desert-like situations are responsible for the increase in the frequency of wildfires. [Climate Change (2007)] According to Blaikie et al (2003) hazards such as hurricanes, typhoons, earthquakes, tsunamis, volcanic explosions, flooding, wildfires must interact with social systems and human vulnerability to qualify the status of “disasters”.
The definition of a natural disaster is pegged on the hazard-vulnerability interaction. This is to say that a natural hazard will never result into a natural disaster if it occurs in areas without vulnerability e. g. strong earthquakes happening in uninhabited lands. However, the most sensitive issue is establishing the cause of disasters. For instance, whereas some disasters are directly caused by mans activities others are caused by natural factors such as global warming, lightening, earthquake, etc.
Wildfires for instance, are an example of natural disasters that are mainly caused by changes in climatic conditions. A wildfire, also known as, forest fire, vegetation fire, or bush fire, is an uncontrolled fire in wild land that are caused by both man activities and natural factors such as global warming and lightening. A fire requires three basic things to burn: fuel, oxygen, and heat. In the case of wildfires the fuel is trees, shrubs, and grasses, especially those that are dead and dry.
The air in our atmosphere which is made up of 21% of oxygen, supplies the oxygen that the wildfires needs to burn. On the other hand, the high temperatures supply heat. Study Methodology This research study involves two variables (global warming: independent and wildfires: dependent) which are directly linked to one another. In order to investigate the interrelation between these two variables, findings of various articles that describe research studies carried out by other researchers on the issue will be studied. This paper will utilize findings from reliable research studies only.
In ‘reliable research studies’ it is referred to those studies whose findings were published in reputable journals, have been peer reviewed, or were presented in global meetings on climate as compiled reports. Only those articles that are published in journals such as Science Express, Climate Change, National Wildlife, and PNAS will be utilized. In order to provide an argument that can be defended, sufficient data will be collected that will be comprised of vital information about the research studies used such as the duration of time covered by the data collected, methods used in analyzing the data, and findings.
Each article’s findings and other relevant data will be treated independently in order to have an independent comparison at the end of the study that will lead to. There are many articles that discusses the issue of wildfires as a natural hazard caused by natural factors such as lightening, however, in order to offer tangible support to the study’s refined hypothesis, major emphasis will be put on those articles that discusses global warming as the core factor to increase in wildfires (as the refined hypothesis boldly states). References:
Fried, J. S. , Torn, M. S. and Mills, E. (2004). The Impact of Climate Change on Wildfire Severity: A Regional Forecast for Northern California. Climate Change, 64, 169-191, accessed on April 1, 2009 Kitzberger, T. , Brown, P. M. , Heyerdahl, E. K. , Swentnam, T. W. , and Veblen, T. T. (2007). Contingent Pacific-Atlantic Ocean influence on multi-century wildfire synchrony over western North America. PNAS, 104, 2, 543-548, accessed on April 1, 2009 Marlon, J. R. et al (2009). Wildfires responses to abrupt climate change in North America.
Field, C. B. (Ed. ) PNAS. Vol. 106 No. 8 2519-2524, accessed on April 1, 2009 “Summary for Policy Makers. ” Climate Change 2007: The Physical Science Basis. Contribution of Working Group 1 to the Fourth Assessment Report of the Intergovernmental panel on Climate Change. (Available online at; http://ipcc-wg1. ucar. edu/wg1/Report/AR4WG1), accessed on April 1, 2009 Running, S. W. 2006. Climate Change: Is Global Warming causing more, larger wildfires. Science Express; Jul 2006, Vol. 313, No 5789, 927-928, accessed on April 1, 2009
Tolme, P. , (2004). Will Global Warming cause more wildfires? National Wildlife, 42, 5, 14-16, accessed on April 1, 2009 Westerling, A. L. , Higalgo, H. G. , Cayan, D. R. , and Swetnam, T. W. (2006). Warming and earlier spring increase Western U. S. Forest Fire Activity. Science, 313, 940-943, accessed on April 1, 2009 Wisner, B. , Blaikie, P. , Cannon T. , & Davis, I. (2004). At Risk – natural hazards, people’s vulnerability and disasters. Wiltshire: Routledge. ISBN 0-415-25216-4, accessed on April 1, 2009Sample Essay of RushEssay.com