By: Catherine Wiedor

1. How Tropical System Intensity in the Gulf of Mexico Is Affected by Human Alterations of the Inorganic Carbon Cycle and the need for a possible modification to the Saffir-Simpson Scale By: Catherine Wiedor

2. Outline of Presentation • Introduction: • The issue at hand: Increasing severity of tropical systems • Tropical system formation • Factors involving tropical system development • Methods of Research: • Examining the components of specific tropical system factors (natural cycles) • Results: • Placing the connection between increasing severity of tropical systems and human interactions on natural cycles, and the possible warranting of a modification to the Saffir-Simposn Scale • Conclusions: • What can we do about this issue?

3. Introduction: Why Tropical Systems • Tropical systems in the Gulf of Mexico region are currently a pressing issue • Hurricanes, tropical storms, tropical depressions - life-threatening natural disasters that strike the U.S. Gulf of Mexico Region • Caused Americans To: • Learn of the severity of tropical systems • Seek a better understanding of their specific mechanisms

4. Total Number of Storms In Atlantic Basin from 1960-2007

5. Category 4 and 5 Hurricane Highest Wind Speed (Maintained For At Least 10 Minutes)

6. How Tropical Systems Are Classified

7. Difference In MPH In Categories

8. Because there have only been six Category 5 hurricanes on record since 1960 there was not a need for a category six on the Saffir-Simpson Scale. • However, there have been 13 storms that have reached 15 mph over the Category 5 status since 1960. (Wind speed was maintained for at least 10 minutes)

9. 2005: A Record-Breaking Year for Tropical Storms • The largest number of storms (27) and the largest number of hurricanes (14) • The only year with three category 5 hurricanes • The most intense storm on record (Wilma), the most intense storm in the Gulf of Mexico (Rita) and the most costly storm on record (Katrina) (Anthes2006)

11. Change in the number and Intensity of hurricanes in categories 4 and 5 for the 47-year periods

12. What Could be Responsible for an Increase in Storm Severity? • Tropical Systems → influenced by atmospheric and oceanic sequences: • Natural Earth cycles (Carbon, Water, Nitrogen, etc) • Both physical and chemical interactions • Can there be a connection between the increasing intensity of tropical systems and human changes within the inorganic carbon cycle?

13. Research Hypothesis • As further human alterations of the inorganic carbon cycle increase, atmospheric and oceanic temperatures will also continue to rise, which will lead to an escalation of the intensity of tropical systems in the Gulf of Mexico and a modification of the Saffir- Simpson Scale.

14. The Formation of Tropical Systems • Begins with the appearance of tropical disturbances, usually a cluster of oceanic thunderstorms • Typically found in mid-Atlantic Region • Tropical storms will form with high humidity (8-20° latitude), medium winds, and warm sea surface temperatures (>26°C )(Lindsey 2006) Figure 1: Typical Life cycle of Caribbean/Atlantic Tropical Systems (Britannica 2006)

15. Tropical System Formation • The atmospheric condensation process of water vapor, along with warm temperatures and proper pressure, can trigger cycles of sustained winds • Sustained winds at 0-38 miles per hour → tropical depressions • At 39 miles per hour → tropical storm status (name given) • At 74 miles per hour → hurricane status (category assigned) (Lindsey2006) • Most tropical systems from the Atlantic Ocean to the Gulf of Mexico rely on warm oceanic temperatures in order to develop, breakdown over land

16. The Factors Affecting Tropical Systems • Main contributing factor to tropical system intensity: ↓ ↓ Sustainable warm ocean temperatures (Lindsey 2006) • Most likely cause for an increase in warm ocean temperature → global warming • Global warming → the increase in global surface temperature due to trapped thermal heat from the sun and trapped heat radiated from Earth

17. What Affects Sea Surface Temperature • The trapping of this heat is primarily caused by greenhouse gas emissions • The increase and decrease of greenhouse gases over time → shown to correlate with increases and decreases in global temperature • The process of global warming → nearly direct effect on oceanic surface temperatures (Anthes 2006) • Temperature - the definitive ingredient in the formation of tropical storms

18. Interactions between the Ocean and the Atmosphere • Physical relationships: • Precipitation from atmospheric moisture cycles from the ocean through the atmosphere • Sea surface temperature and other heat exchanges (condensation) from atmospheric conditions • Also development of surface winds and sustainable winds through atmospheric conditions Figure 2: Ocean and Climate, Physical Coupling with the Atmosphere (Herring 2006)

19. Interactions between the Ocean and the Atmosphere Continued • Chemical relationships: • Chemical interactions with Greenhouse gases – primarily the exchange of water vapor and carbon dioxide • Also these interactions compliment the physical interactions between oceans and the atmosphere, such as heat exchange • Much of the heat that escapes the ocean is in the form of water vapor; the most significant greenhouse gas (Herring 2006) • A fairly direct relationship exists between the presence of greenhouse gases and the physical processes that occur in the atmosphere and oceans Figure 3: Oceans and Climate: Chemical Coupling with the Atmosphere (Herring 2006)

20. Atmospheric/Oceanic Processes Resulting from Natural Cycles • The chemical relationship between the atmosphere and ocean is constructed of many natural cycles: • (Global) carbon cycle • Water cycle • Nitrogen cycle • The global carbon cycle: • Exchange of carbon material (organic carbon material and inorganic CO2 gases) • Pathway: travels through the atmosphere, oceans, terrestrial (land) interactions, back into atmosphere (Fung 2005)

21. The Global Carbon Cycle • Stella Modeling of Carbon interactions within atmospheric, oceanic, and terrestrial regions • Organic Process (mostly occurring in the terrestrial region) simplified with the model

22. Aspects of the Inorganic Carbon Cycle • The inorganic carbon cycle - a main participant in the interactions that contribute to tropical system development • Any increase in atmospheric CO2 levels generally leads to an increase in absorption of CO2 in ocean waters through the inorganic carbon cycle (Fung 2006) • Small (natural) increases in CO2 concentration in ocean waters → does not affect the cycle to a significant degree

23. The Human Influence of the Inorganic Carbon Cycle • Large increases in CO2 concentration in the ocean waters -amplification of the inorganic carbon cycle • Inorganic carbon constantly re-circulates through atmospheric/oceanic/terrestrial regions • No substantial amounts of inorganic carbon material is lost through the system • Every part of system is affected by an atmospheric change of Carbon • Linking the human alterations of the inorganic carbon cycle to increasing sea surface temperature

24. Conclusions: How These Elements of Global Warming Affect Tropical System Intensity • Summary of Concepts: • Tropical storms form when conditions are met: medium winds, pressure, and warm sea surface temperatures • Warm sea surface temperature most important factor in development and intensity of tropical system intensity • Warm sea surface temperature influenced by the greenhouse effect and greenhouse gasses, increasing over the last century

25. Conclusions Continued • Summary of Concepts Continued: • Increase in Greenhouse gases primarily due to unnatural increasing carbon rates in the atmosphere • Human alteration of amounts of atmospheric carbon → impact on carbon cycle • Carbon cycle then influences sea surface temperature → general increase in tropical system intensity • If tropical systems intensify as predicted then a modification to the Saffir-Simpson will be warranted Figure 4: Monthly Mean Surface Temperatures v. Maximum Wind Speeds for Atlantic Tropical Systems (Emmanuel 1991)

26. Predicted Atmospheric Carbon Levels – 1995 - 2095 • Graph displays the predicted atmospheric carbon levels from 1995 – 2095 using basic carbon cycle (including both organic and inorganic carbon) Stella modeling • Initial Value for amount of CO2 in atmosphere: 350 ppm • Projected Value in one hundred years: ~ 600 ppm!

27. What Can We Do to Help? • The most important step in solving the problem is becoming educationally aware of the situation: • Understand how this problem is a global issue, one shared by ALL • Recognize your individual contribution to the issue, and some methods to become “carbon neutral’ • Providing Information to U.S. Citizens of the Gulf Coast Region: • Better preparations for tropical systems • Suggestions for improving defenses against such storms

28. Works Cited Anthes, R.A., Corell, R.W., Holland, G., Hurrell, J.W., Maccracken, M.C., and Trenberth, K.E. 2006. Hurricanes and Global Warming - Potential Linkages and Consequences. Bull Am Meteorol Soc 87. 5:623-631. Emanuel, K A. 1991. Comments on Carbon Dioxide and Hurricanes: Implications of Northern Hemispheric Warming for Atlantic/Caribbean Storms. Meteorol. Atmos. Phys. 47: 83-84. Fung, I.Y., Doney, S.C., Lindsay K., and John J. 2005. Evolution of Carbon Sinks in a Changing Climate. Proceedings of the National Academy of Sciences of the United States of America. PNAS 102. 32: 11201-11206. Herring, David. "Ocean & Climate." 2006. NASA Earth Observatory. <http://earthobservatory.nasa.gov/Library/OceanClimate/oceanclimate.html> (24 October 2006)

29. Works Cited Continued Lindsey, Rebecca. "Hurricanes: the Greatest Storms on Earth." 2006. NASA Earth Observatory. <htttp://earthobservatory.nasa.gov/Library/Hurricanes/hurricanes_1.html> (24 October 2006) Rahmstorf, S. 2000. The Thermohaline Ocean Circulation: A System with dangerous Thresholds. Climatic Change46: 247–256. “Tropical cyclone: Life Cycle of a North Atlantic hurricane." Encyclopedia Britannica Online. <http://www.britannica.com/eb/art-75358> (24 October 2006) Webster, P.J., G.J. Holland, J.A. Curry, and H.R. Chang. 2005. Changes in Tropical Cyclone Number, Duration, and Intensity in a Warming Environment. Science Magazine 309: 1844-1846.