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Increased Storm Intensity due to Climate Change:

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1 Increased Storm Intensity due to Climate Change:
TROPICAL STORMS AND HURRICANES - Important topic because climate change is a something that has been and will continue to be a hot topic for debate. With the increase in greenhouse gasses it is important that we asses the risks that come along with increasing global temperatures. Marques Miller Jordan Langworthy

2 What is climate change? Substantial increase in global temperatures over a long period of time. Greenhouse effect. Ocean circulation 1.Global warming does not necessarily imply that the world’s temperature is continuously increasing in a linear fashion. Instead, the earth’s climate has been known to fluctuate over short periods of time. Global warming instead is referring the substantial warming in climate that has occurred over a much longer period of time. 2.Global warming is most commonly associated with the greenhouse effect: Greenhouse gasses in the atmosphere absorbing and deflecting radiation, thus trapping it in the earth’s atmosphere causing an energy and heat buildup.

3 Climate Change Predictions
1. Global temperature changes during the 20th century. The blue line depictures only changes due to natural forces triggered by solar activity and volcanoes. The red lines is made up of changes induced by natural and anthropogenic sources (Graphic: IPCC) 2. The UN’s most likely global warming scenario describes a world of new and more efficient technologies where energy comes from a number of well-balanced sources. Still, at the end of the century, temperatures will have increased by up to six or seven degrees Celsius in the Arctic, about three degrees in Europe, and three to four degrees in Asia and the Americas

4 Tropical Storms and Hurricanes
How are they formed? Warm ocean water Low pressure systems The temperature of the water must at least be 81 degrees F. The reason any hurricane thrives over heated waters, is because the water is a form of energy, and the heat from the water gives the storm strength to get larger and more destructive. This brings us to the topic of global warming because as global temperatures increase, so do sea surface temperatures, thus potentially increasing the risk of tropical storm and hurricane formation.

5 Considering factors when assessing storm intensity and occurrence
Frequency Storm Surge Wind speed Inland effect Hurricane Level 1 (Weak) 74-95 mph No real damage to building structures. Damage primarily to unanchored mobile homes, shrubbery, and trees. Also, some coastal road flooding and minor pier damage. Level 2 (Moderate) mph Some roofing material, door, and window damage to buildings. Considerable damage to vegetation, mobile homes, and piers. Coastal and low-lying escape routes flood 2-4 hours before arrival of center. Small craft in unprotected anchorages break moorings. Level 3 (Strong) mph Some structural damage to small residences and utility buildings with a minor amount of curtainwall failures. Mobile homes are destroyed. Flooding near the coast destroys smaller structures with larger structures damaged by floating debris. Terrain continuously lower than 5 feet ASL may be flooded inland 8 miles or more. Level 4 (Very Strong) mph More extensive curtainwall failures with some complete roof structure failure on small residences. Major erosion of beach. Major damage to lower floors of structures near the shore. Terrain continuously lower than 10 feet ASL may be flooded requiring massive evacuation of residential areas inland as far as 6 miles. Level 5 (Devastating) 156- mph Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. Major damage to lower floors of all structures located less than 15 feet ASL and within 500 yards of the shoreline.Massive evacuation of residential areas on low ground within 5 to 10 miles of the shoreline may be required. 

6 Frequency Change in the number and percentage of hurricanes in categories 4 and 5 for the 15-year periods 1975–1989 and 1990–2004 for the different ocean basins. Period Basin Number Percent Number Percent East Pacific West Pacific Northern Atlantic Southwest Pacific North Indian South Indian Duration of a storm has a number of factors, such as wind speed, geography of the impact area, intensity of overall storm, and geography of impact slope. Frequency of storms tend to be on a interval due to La Ninas, and El Ninos.

7 Storm Surge Definition Effect Factor of Influence SLOSH
water that is pushed toward the shore by the force of the winds swirling around the storm. This advancing surge combines with the normal tides to create the hurricane storm tide, which can increase the mean water level 15 feet or more. In addition, wind driven waves are superimposed on the storm tide. This rise in water level can cause severe flooding in coastal areas The level of surge in a particular area is also determined by the slope of the continental shelf. A shallow slope off the coast (right, top picture) will allow a greater surge to inundate coastal communities. Communities with a steeper continental shelf (right, bottom picture) will not see as much surge inundation, although large breaking waves can still present major problems Sea, Lake and Overland Surges from Hurricanes is a computerized model run by the National Hurricane Center (NHC) to estimate storm surge heights and winds resulting from historical, hypothetical, or predicted hurricanes by taking into account Pressure Size Forward speed Track Winds

8 Wind Speed ACE Damage Accumulated Cyclone Energy (ACE) =
The ACE index is a wind energy index, defined as the sum of the squares of the maximum sustained surface wind speed (knots) measured every six hours for all named systems while they are at least tropical storm strength.

9 Inland Effect Inland cities Topography Flooding Pressure release
As a result, the highest proportion of hurricane and tropical fatalities has shifted inland. One study cited in the Matyas paper found 59 percent of deaths from tropical storms or hurricanes between 1970 and 1999 occurred because of heavy rainfall rather than wind or storm surge. Storms near the Appalachians also line up parallel to the mountains, whose axis runs southwest to northeast, with the heaviest rain consistently occurring to the west of the track. This is due to a combination of the mountains and a wedge of cold and dry continental air forcing the moist air upward, causing the water vapor to condense and fall to the ground as rain As the storm moves inland, pressure is released from the hurricane causing rapid rainfall. Channels crisscross the marshlands, dredged for boat traffic. They let salt water into the back marshes, killing vegetation that holds them together. Add all the dikes and levees that hem in the Mississippi, cutting off the sediment that once replenished the marshes, and the result is staggering: More than 20 percent of Louisiana's coastal wetlands reverted to open water from the 1950s through 2000, 27 square miles (70 square kilometers) every year

10 Increased SST increases the energy input into storm systems
Is there a link? Increased SST increases the energy input into storm systems Greenhouse gasses cause heat to be trapped in the earth’s atmosphere causing temperatures to rise Rising temperatures cause ocean waters to increase in temperature, thus storing heat energy Heat energy from surface waters is extracted from the ocean by storm systems and transferred into mechanical energy The kinetic energy is then released by the storm through wind energy and cloud/rain formation One popular theory: The energy cycle of the mature hurricane has been idealized as an engine that converts heat energy extracted from the ocean to mechanical energy. In the steady state, this mechanical-energy generation balances frictional dissipation, most of which occurs at the air-sea interface. The theory suggests a relationship involving storm intensity increasing with sea surface temperature, and the rate of increase also gets steeper at higher sea surface temperatures. Emanual, A Kerry “The Theory of Hurricanes.” Annual Reviews: Fluid Mechanics. 23 (1991) Web. Nov Heat energy theory of cyclone intensity

11 Is there a link? *2003 case study
Attempted to find a link between tropical storm/hurricane intensity and sea surface temperatures. Results were inconclusive when looking to find a linear relationship. 1. Figure 6 shows that, all other factors being equal, relatively small variations in inner-core SST can dramatically impact inner-core surface heat flux and, as such, the magnitude of upper-ocean energy extracted by the storm (QHpext). Figure 6 illustrates that a +0.7 degree C difference in inner-core SST (i.e., average DSSTIC between upper and lower 50th percentile samples shown in Table 3) results in a 30% increase in the amount of upper-ocean energy extracted by the storm. 2. But they concluded that because most hurricanes utilize less than 10% of the upper-ocean energy available to them, and due to a lack of reliable observations they could not clearly conclude that storm intensity was increasing due to increases in temperature Cione, Joseph J., and Eric W. Uhlhorn "Sea Surface Temperature Variability in Hurricanes: Implications with Respect to Intensity Change." Monthly Weather Review (2003): Academic Search Premier. EBSCO. Web. 14 Nov

12 Is there a link? A report published in 2009 took a slightly different approach Analyzed “potential intensity” 1. A study done in 2009 revisited this topic and concluded that overall intensity may not be linearly increasing, but rather the potential energy of the storms. 2. This “potential intensity” is defined strictly by the local ambient thermodynamic conditions surrounding an existing storm and is based on factors that can be directly measured with existing temperature and moisture data. 3. They concluded that there were many other factors that affected the intensity of the storms such as wind shear, ocean circulation, El Niño and La Nina, and storm tracks. But overall the increase in sea surface temperatures provided the energy needed for the strongest storms to become stronger. Kossin, James P., and Suzana J. Camargo "Hurricane track variability and secular potential intensity trends." Climatic Change 97.1/2 (2009): Academic Search Premier. EBSCO. Web. 14 Nov

13 Additional suspected effects of climate change
Melting of glaciers can cause the sea levels to rise Warm air can hold more moisture possibly affecting rainfall "In addition, as oceans warm and glaciers melt, sea levels will continue to rise," Ekwurzel says. "Higher sea levels mean bigger storm surges, even from minor storms, causing coastal flooding, erosion and property damage.“ Warren, Luke "Global Warming and Hurricanes." Mother Earth News 213 (2005): 22. Academic Search Premier. EBSCO. Web. 14 Nov

14 Human Cost Coastal Living Money due to damage Infrastructure effect
Impact of Hurricanes Katrina Andrew Ivan Rita Wilma Dean Insured Loss  (millions of dollars) 45,000 22,274 11,684 10,000 ,500 (est.) [1] Total Loss  (millions of dollars) 81,000 55,800 15,500 20,600 TBD Date 8/05 8/92 9/04 9/05 10/05 8/07 Country US/Mexico US Bahamas US/Barbados US, Mexico, Cuba US, Mexico, Jamaica, Haiti US, Mexico, Jamaica, Cayman Islands Coastal Living Money due to damage Infrastructure effect Prediction/Prevention 1. . As storms track inland, they inevitably ensnare more cities and towns. Population is burgeoning along vulnerable coasts in the U.S., Asia, and the Caribbean. In the southeastern U.S., for example, coastal populations grew more than 50 percent from 1980 to 2003. 2. While hurricanes can make land fall and travel inland, coastal areas like Florida and the gulf of Mexico are typically the most affected. In recent years hurricanes such as Katrina and Rita have been responsible for over a $100B in property damage and billions more in lost productivity. Hurricanes destroy both personal property and commercial property and can result in huge losses for insurance companies. These storms also have the potential to disrupt the operations of oil refineries found off the gulf coast, resulting in lost production. This can also lead to rising oil prices which harm a myriad of industries from airlines to toy companies. Health issues such as disease, contamination ext. 3. Weather satellites make it easy for meteorologists to keep tabs on hurricanes. But ordinary satellite images show only the cloud tops. Spaceborne infrared sensors can reveal more detail, charting the size and shape of the warm eye, and satellite radar and microwave sensors can map the rain. Hurricane hunter aircraft actually fly right into Atlantic hurricanes. But they only probe conditions at altitudes of several thousand feet, above the worst turbulence. Three-day forecasts of Atlantic storm positions were off by an average of 440 miles (708 kilometers) in the 1970s; by 2005 the average error had dropped to 173 miles (278 kilometers). But one-day forecasts were still wide of the mark by an average of 70 miles (113 kilometers)—more than enough to keep coastal dwellers second-guessing the experts. The data and models still can't capture storms in enough detail to forecast all of their feints and swerves. Three-day wind-speed forecasts, off by an average of 23 miles per hour (37 kilometers per hour) in the early 1990s, had improved only marginally by Hurricanes regularly surprise observers with their mood shifts. In a matter of hours, a Category 5 storm (winds over 155 mph, or 249 kph) can fade to a Category 3 ( mph, or kph), or a mere tropical storm can explode into a killer. "Intensity changes are the things that really hurt people. Building codes Bracing. Hurricane Straps Hurricane Shutters Double Entry Door Kits you should keep the trees surrounding the structure trimmed at all times Loose items that surround the structure should be secured

15 Sources Cione, Joseph J., and Eric W. Uhlhorn "Sea Surface Temperature Variability in Hurricanes: Implications with Respect to Intensity Change." Monthly Weather Review (2003): Academic Search Premier. EBSCO. Web. 5 Nov Kossin, James P., and Suzana J. Camargo "Hurricane track variability and secular potential intensity trends." Climatic Change 97.1/2 (2009): Academic Search Premier. EBSCO. Web. 5 Nov Emanual, A Kerry “The Theory of Hurricanes.” Annual Reviews: Fluid Mechanics. 23 (1991) Web. Nov Mann, Michael E., et al. "Atlantic hurricanes and climate over the past 1,500 years." Nature (2009): Academic Search Premier. EBSCO. Web. 7 Nov Warren, Luke "Global Warming and Hurricanes." Mother Earth News 213 (2005): 22. Academic Search Premier. EBSCO. Web. 8 Nov


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