Global WarmingA paper by Michael DeFino The story of global warming is becoming increasingly popular and the fear continues to rise among many Americans wondering if this is truly happening or not. Just like scientists, most people have taken a side on this issue and those two sides are; global warming is happening and global warming is not happening. The main arguments for those that believe in global warming, is that the warming of the earth is caused by humans. Those who do not believe in global warming believe that this recent warming is a natural process. The arguments raised by those, who believe in global warming will be looked at and analyzed and be proven as a natural cycle or wrong. Through much of the data discussed it will prove that global warming is not occurring due to inaccurate global temperatures, past historical data on temperatures and hurricanes, oscillations, and the climate of the Arctic and Antarctica. Richard Lindzen provides excellent information in his research on global warming. Lindzen talks about the positive side of increasing levels of CO2 in the Earth’s atmosphere. Lindzen says, “For example, at altitudes between 25 km and 90 km, the atmosphere is cooled primarily by thermal radiation emitted to space by CO2, increasing CO2 should cool these regions and should lead to increasing concentrations of ozone at these levels” (288). That statement is crucial because the misconception is that CO2 is one of the main causes of ozone depletion. Lindzen explains the problems with climate models by saying, “About the only thing existing climate models agree on is the warming will be greatly exaggerated in Polar Regions…unfortunately observations show that exactly the opposite has occurred in the Arctic” (292). Charts shown in Lindzen’s paper show that the warmest time period at the Atlantic Arctic was between 1930-1945, which coincides with the warm phase of the Pacific Decadal Oscillation (PDO) (295). The positive phase of the PDO favors an El Nino; it has a huge cold pool of Sea Surface Temperatures (SSTs) in much of the Northern Pacific and across the Atlantic (Mantua). The negative phase of the PDO favors a La Nina, which is the reversal of the SSTs with a huge warm pool in place of the cold pool from the positive PDO (Mantua).
Stephen Schneider also supports some of the previous points mentioned above, “It has been argued that because much of the warming in the 20th century took place between 1915-1940’s, followed by a cooling at the time the global greenhouse gases were increasing” (1295). This fact shows that greenhouse gases cannot have an impact on the temperatures. Schneider also mentions that nature changes from year to year and these fluctuations are normal. The climate models may not be picking up fluctuations like this and that could be affecting the result. With are latest technological advances we can better detect a lot, Schneider says, “Fortunately, we are now monitoring the sun, volcanoes and pollution-generated particles more accurately, and can thus better account for their effects” (1296). James Hurrell and Kevin Trenberth have done research on the difficulties in gathering global temperature. At the beginning of this article Hurrell and Trenberth say, “The absence of upward trends in the recent satellite record has been used by some as ‘proof’ that global warming is not occurring and that instrumental record of surface temperature cannot provide a reliable measure of climate change” (945). Both sides of the argument agree that global temperature cannot be focused just on land areas and that the patterns over the oceans need to be taken into account. Hurrell eludes to this, “Since the late 1970s, changes in atmospheric circulation have resulted in surface warmth over the northern continents and coolness over the oceans” (947). The conclusion of this article is simply that all the disagreement and confusion is over the tropical areas with Sea Surface Temperatures being a problem. Global Temperatures based off satellite:
Recent increase in hurricane activity during the 2005 season has led to many believing in global warming. Scientists, who believe in global warming, are using these strong hurricanes in there defense. History shows that land falling hurricanes similar of the 2005 season has happened before and similar active hurricane seasons have seen documented in the past. In research done by Partagas and Diaz, they highlight 1887 which featured a similar season to 2005. The tracks of these hurricanes in the 1887 season that made landfall hit several areas that were hit in the 2005 season. The similarity did not only exist in number of storms, but they were also identical in storm tracks. The first system to make landfall was a weak tropical storm that hit an area similar to Hurricane Katrina (1887 Hurricane/Tropical Data). The second system to make landfall was a category 2 hurricane that hit the panhandle of Florida. Next was a category 3 hurricane that brushed the North Carolina coastline (1887 Hurricane/Tropical Data). The fourth system was four days later and followed the same path as the previous Hurricane and was slightly stronger. The fifth storm in this year hit extreme Southern Texas as a category 2 hurricane (1887 Hurricane/Tropical Data). Next storm hit the New Orleans area as a category 1; this was the second storm in the season to give New Orleans a big hit. The last land falling hurricane of the season developed in the Gulf of Mexico and hit the western shoreline of Florida as a weak category 1 (1887 Hurricane/Tropical Data). The 1887 season started with a tropical storm May 15th and ended with a tropical storm December 12th.
(Unisys Weather)
Partagas and Diaz say, “The total number of storms for this 40-yr period, 1851-90, is 298, an increase of 105 (nearly 55%) over previously published figures” (2901). With the latest technology in the second half of the 20th century we can track these storms with satellite and hurricane hunters. During the second half of the 19th century there was no technology sufficient enough to locate a hurricane, such as satellite. The first successful flight for the hurricane hunters was in 1944, therefore; in the 19th century they had very little information to work with in forecasting when a hurricane would hit. The only way a hurricane was detected before satellite was shipping reports and journals of people keeping daily weather observations. The intensity of these hurricanes was an estimate because the maximum wind reports could have been on the outer edge of the storm or further away. The hurricane hunters fly right into the eye of the storm and receive data with maximum wind speeds and maximum wind gusts along with other data. This explains why we have had several more major hurricanes in the last 30 years. The 1887 season recorded 0 major hurricanes, while the 2005 season recorded 5 major hurricanes (1887 and 2005 Hurricane/Tropical Data). Is this global warming or simply because we have more technology to diagnosis these storms? It is similar to our problem today with tornados and other severe weather with the lack of storm spotters reporting information to the national weather service. Meteorologist Joe D’Aleo shared some findings in research of a cold October, The AO/NAO was mostly negative during the cool phase of the PDO and mostly positive during the warm phase” (Major Circulation Shifts Mark Turn to Cold and Unusually Early Snow). The Arctic Oscillation (AO) is a measure of pressure in the Arctic. A negative phase of the AO is when high pressure dominates the polar region allowing the cold air to drop down into the United States, Northern Europe, and Russia (D’Aleo). During a positive phase, low pressure dominates the polar region allowing for the cold air to stay wrapped up near the poles keeping much of the United States, Russia, and Northern Europe above average for temperatures (D’Aleo). Thompson worries that the positive phase that dominated the 1980’s and 90’s could lead to global warming, It is conceivable that this change in the behavior of the Arctic Oscillation could be linked to the buildup of greenhouse gases in the atmosphere.” The positive phase dominated during a time period when the warm phase of the PDO was in full force, backing up Joe D’Aleo’s research. As we draw to a near of the 30 year cycle of the warm phase of the PDO and enter a cold phase this will allow the negative phase of the AO to dominant.
Dr. Hanna, from the Institute of Marine Studies at the University of Plymouth, UK, reports “There are a lot of natural cycles in regional climate and if you take a longer trend over the last 40 or 50 years then there has been a statistically significant cooling, particularly in south-western coastal Greenland.” D’Aleo also mentions the North Atlantic Oscillation (NAO), this is an oscillation similar to the AO. During the positive phase of the NAO, low pressure is over Southern Greenland leading to warmer than normal conditions across the United States and Northern Europe (D’Aleo). The negative phase is the opposite with a high pressure over Southern Greenland and colder than normal temperatures across the United States and Northern Europe (D’Aleo). The NAO is thought to be the main cause of this cooling over Greenland. The last 30 years the NAO has been in more of a positive phase due to the warm phase of the PDO, allowing Greenland to experience an extended period of time of below average temperatures. When the cold phase of the PDO takes over it will allow the pattern to favor a negative NAO.
Alaska is the last area on the list to address in respect to the warming temperatures. Permafrost is melting and glaciers are retreating, but this trend will not continue as we look at the effect of the PDO. A warm phase of the PDO places a huge warm pool of water in the Gulf of Alaska, in return this correlates with higher pressure anomalies over Alaska. When the PDO shifts to the cold phase that warm pool of water will be replaced with a cold pool of water (Mantua). These fluctuations in the Gulf of Alaska are referred to as the Eastern Pacific Oscillation. The negative phase places a ridge in the Gulf of Alaska, while the positive phase places a trough. These phases affect the temperatures across much of North America, a positive phase means warmer than average temperatures for most of the United States into Southern Canada (D’Aleo). The negative phase is the opposite and produces colder weather across most of the United States into Canada (D’Aleo). The only major factor that gave us a huge arctic outbreak across the Eastern United States this past winter was the flip from a positive phase of the EPO to a negative phase. A positive phase of the EPO is favored in a warm phase of the PDO, while a negative phase of the EPO is favored in the cool phase of the PDO. This would go against the cooling process in the Eastern United States, however; if other indices such as the AO/NAO are negative it will still allow for below average temperatures in the Northeast and Northern Middle-Atlantic. Positive phase of the EPO ( D’Aleo):
Example of negative EPO (Plymouth State College):
Oliver and Hidore talk about sea level changes in the past and future with the melting of the ice in the poles. The chart used in Oliver and Hidore’s work shows the global mean sea level over the last 150,000 years. The confidence in these measurements is probably not high given the lack of data, but the graph does show that 100,000 years ago we were 20 meters above normal and today we are on the rise with normal at zero (269). Given the consistency with the zero over the last few thousand years it could be assumed that this process is natural. History tells us that the sea level peaked well before our time, but the chart shows the steadiness in normal sea level over the last few years which history supports a decrease in future years (269). Oliver and Hidore also mention the climate of Antarctica, “The outstanding feature of the Antarctic landmass is, of course, the huge mass of ice surmounting and surrounding the continent” (248). Data from a station in the South Pole recorded its warmest day on January 12, 1958. The coldest year on record was 1976 and researchers show that this cooling is causing many to question where this cooling is coming from (247). NASA researchers say, While Antarctica has mostly cooled over the last 30 years, the trend is likely to rapidly reverse, according to a computer model study by NASA researchers.” Going back to research done by Lindzen he proves that these models that have data and research from greenhouse gases computed in them to come out with a forecast. The question is how we can have a forecast model for the next 50 years if we do not have a clue about the current climate of Antarctica and the unexplained cooling trend. For further research on global warming it is going to take time to see how data matches up. One of my major arguments to disprove global warming is the phases of the Pacific Decadal Oscillation (PDO). It matches up perfectly with reports of the increase in El Nino during the past 30 years and the cooling from 1945-1970. This would back up the statement made in Hurrell’s argument that the cooler pattern over the oceans since 1970’s is the result of a positive PDO. To continue this research we might see signs of the PDO switching phases this upcoming summer with a La Nina expected. This could be the start of a negative phase based off the history of the PDO. Possible problems that could occur are if this positive phase never ends, it has been in charge for about 30 years, which is typical of a warm phase. Latest climate models, especially the AGCM, show the La Nina starting to develop now and will develop maturely by the summer time. Most meteorologists thought that the recent cold phase of the PDO in 1999-2000 was the start to a cool phase, but data shows it was only a flux (Mantua). Past data shows it is common to have a flux like this before a dominant changeover for both phases.
Another climate model that is used for seasonal predictions also agrees with the forecast for a La Nina. The International Research Institute (IRI) model shows a forecast from April of SSTs for the Northern Hemisphere. The model shows a cold phase of the PDO developing with the SST configuration and La Nina. This could be the official beginning of the cold phase and could start to put the global warming concept to rest. Image by Unisys Weather shows cold pool of water in the Gulf of Alaska with cold water extending down through the Western US. This is a sign of a developing cool phase. AGCM Model (below) shows the developing La Nina and the most recent forecasts for the La Nina in the coming months.
Works Cited Amos, Jonathan. “Greenland Cools as World Warms.” BBC News. 11 Mar. 2003. BBC News. 10 Apr. 2007 <http://news.bbc.co.uk/2/hi/science/nature/2840137.stm>. D’Aleo, Joe. “Major Circulation Shifts Mark Turn to Cold and Unusually Early Snow.” Intellicast. 15 Oct. 2002. Chief WSI/INTELLICAST Meteorologist. 10 Apr. 2007 <http://www.intellicast.com/DrDewpoint/Library/1355/>. Fernandez-Partagas, Jose, and Henry Diaz. “Atlantic Hurricanes in the Second Half of the Nineteenth Century.” American Meteorological Society 77 (1996): 2899-2907. Louis L. Manderino, California. 10 Apr. 2007. Hurrell, James W., and Kevin E. Trenberth. “Difficulties in Obtaining Reliable Temperature Trends: Recording the Surface and Satellite Microwave Sounding Unit Records.” American Meteorological Society 11 (1998): 945-966. Louis L. Manderino, California. 11 Apr. 2007. Lindzen, Richard S. “Some Coolness Concerning Global Warming.” American Meteorological Society 71 (1990): 288-300. Louis L. Manderino, California. 11 Apr. 2007. Mantua, Nathan. “The Pacific Decadal Oscillation.” University of Washington. 12 Apr. 1997. University of Washington. 14 Apr. 2007 <http://www.atmos.washington.edu/~mantua/REPORTS/PDO/PDO_egec.htm>. Oliver, John E., and John J. Hidore. Climatology: an Atmospheric Science. 2nd ed. Upper Saddle River: Prentice Hall, Inc., 2002. 247-269. Schneider, Stephen H. “The Global Warming Debate Heats Up: an Analysis and Perspective.” American Meteorological Society 71 (1990): 1292-1305. Louis L. Manderino, California. 10 Apr. 2007. Shindell, D.T., and G.A. Schmidt “Study Shows Potential for Antarctic Climate Change.” Goddard Institute for Space Studies. 06 Oct. 2004. NASA. 16 Apr. 2007 <http://www.giss.nasa.gov/research/news/20041006/>. Thompson, Dave, and Vince Stricherz. “Arctic Oscillation Has Moderated Northern Winters of 1980s and ‘90s.” UWNEWS. 5 July 2001. University of Washington. 11 Apr. 2007 <http://uwnews.washington.edu/ni/article.asp?articleID=3187>. “1887/2005 Hurricane/Tropical Data for Atlantic.” UNISYS. 10 Dec. 2005. 20 Mar. 2007 <http://weather.unisys.com/hurricane/atlantic/1887/index.html>.
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