How Tropical System Intensity in the How Tropical System Intensity in the Gulf of Mexico Is Affected by Human Gulf of Mexico Is Affected by Human Alterations of the Inorganic Carbon Alterations of the Inorganic Carbon Cycle and the need for a possible Cycle and the need for a possible modification to the Saffir-Simpson modification to the Saffir-Simpson

ScaleScale

By: Catherine WiedorBy: Catherine Wiedor

Outline of PresentationOutline of Presentation• Introduction:Introduction:

– The issue at hand: Increasing severity of tropical systems The issue at hand: Increasing severity of tropical systems – Tropical system formation Tropical system formation – Factors involving tropical system developmentFactors involving tropical system development

• Methods of Research: Methods of Research: – Examining the components of specific tropical system factors Examining the components of specific tropical system factors

(natural cycles)(natural cycles)

• Results: Results: – Placing the connection between increasing severity of tropical Placing the connection between increasing severity of tropical

systems and human interactions on natural cycles, and the systems and human interactions on natural cycles, and the possible warranting of a modification to the Saffir-Simposn Scale possible warranting of a modification to the Saffir-Simposn Scale

• Conclusions: Conclusions: – What can we do about this issue?What can we do about this issue?

Introduction: Why Tropical Introduction: Why Tropical SystemsSystems

• Tropical systems in the Gulf of Mexico region are Tropical systems in the Gulf of Mexico region are currently a pressing issuecurrently a pressing issue

• Hurricanes, tropical storms, tropical Hurricanes, tropical storms, tropical depressions - life-threatening naturaldepressions - life-threatening naturaldisasters that strike the U.S. Gulf of disasters that strike the U.S. Gulf of Mexico RegionMexico Region

• Caused Americans To:Caused Americans To:– Learn of the severity of tropical systemsLearn of the severity of tropical systems– Seek a better understanding of their Seek a better understanding of their

specific mechanisms specific mechanisms

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

Category 4 and 5 Hurricane Highest Category 4 and 5 Hurricane Highest Wind SpeedWind Speed (Maintained For At Least 10 (Maintained For At Least 10

Minutes)Minutes)

Year Number of Category 4 Highest Wind Speed (MPH) Number of Category 5 Highest Wind Speed (MPH)1960 2 162 (Both) 0 N/A1961 2 173 and 162 0 N/A1964 1 156 0 N/A1965 1 156 0 N/A1967 1 162 0 N/A1969 0 N/A 1 1901971 1 162 0 N/A1977 1 173 0 N/A1979 1 173 0 N/A1980 0 N/A 1 1901988 0 N/A 1 1851989 1 162 0 N/A1992 1 173 0 N/A1998 2 156 and 179 0 N/A1999 2 156 (Both) 0 N/A2003 1 167 0 N/A2004 1 167 0 N/A2005 4 162, 173, and 179 1 1852007 2 173 (Both) 0 N/A

How Tropical Systems Are How Tropical Systems Are ClassifiedClassified

Difference In MPH In Difference In MPH In CategoriesCategories

Category Difference In MPH

Category 1 to 2 21

Category 2 to 3 14

Category 3 to 4 19

Category 4 to 5 24

• Because there have only been six Because there have only been six Category 5 hurricanes on record since Category 5 hurricanes on record since 1960 there was not a need for a 1960 there was not a need for a category six on the Saffir-Simpson category six on the Saffir-Simpson Scale.Scale.

• However, there have been 13 storms However, there have been 13 storms that have reached 15 mph over the that have reached 15 mph over the Category 5 status since 1960. (Wind Category 5 status since 1960. (Wind speed was maintained for at least 10 speed was maintained for at least 10 minutes)minutes)

2005: A Record-Breaking Year for 2005: A Record-Breaking Year for Tropical StormsTropical Storms

• The largest number of storms (27) and the largest number of The largest number of storms (27) and the largest number of hurricanes (14) hurricanes (14)

• The only year with three category 5 hurricanes The only year with three category 5 hurricanes

• The most intense storm on record (Wilma), the most intense The most intense storm on record (Wilma), the most intense storm in the Gulf of Mexico (Rita) and the most costly storm on storm in the Gulf of Mexico (Rita) and the most costly storm on record (Katrina) (record (Katrina) (AnthesAnthes 20062006) )

Change in the number and Intensity of hurricanes in categories 4 and 5 for the

47-year periods

What Could be Responsible for What Could be Responsible for an Increase in Storm Severity?an Increase in Storm Severity?

• Tropical Systems Tropical Systems →→ influenced by influenced by atmospheric and oceanic sequences:atmospheric and oceanic sequences:

•Natural Earth cycles (Carbon, Water, Nitrogen, Natural Earth cycles (Carbon, Water, Nitrogen, etc) etc)

•Both physical and chemical interactionsBoth physical and chemical interactions

• Can there be a connection between the Can there be a connection between the increasing intensity of tropical systems and increasing intensity of tropical systems and human changes within the inorganic carbon human changes within the inorganic carbon cycle? cycle?

Research HypothesisResearch Hypothesis

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

The Formation of Tropical SystemsThe Formation of Tropical Systems

• Begins with the Begins with the appearance of tropical appearance of tropical disturbances, usually disturbances, usually a cluster of oceanic a cluster of oceanic thunderstormsthunderstorms

• Typically found in Typically found in mid-Atlantic Regionmid-Atlantic Region

• Tropical storms will Tropical storms will

form with high form with high humidity (8-20° latitude), humidity (8-20° latitude), medium winds, and warm sea surface temperatures (>26°C )medium winds, and warm sea surface temperatures (>26°C ) (Lindsey 2006)(Lindsey 2006)

Figure 1: Typical Life cycle of Caribbean/Atlantic Tropical Systems (Britannica 2006)

Tropical System FormationTropical System Formation• The atmospheric condensation process of water vapor, along The atmospheric condensation process of water vapor, along

with warm temperatures and proper pressure, can trigger with warm temperatures and proper pressure, can trigger cycles of sustained windscycles of sustained winds

• Sustained winds at 0-38 miles per hour → tropical Sustained winds at 0-38 miles per hour → tropical depressionsdepressions

• At 39 miles per hour → tropical storm status (name At 39 miles per hour → tropical storm status (name given)given)

• At 74 miles per hour → hurricane status (category At 74 miles per hour → hurricane status (category assigned)assigned)((LindseyLindsey 20062006) )

• Most tropical systems from the Atlantic Ocean to the Gulf of Most tropical systems from the Atlantic Ocean to the Gulf of Mexico rely on warm oceanic temperatures in order to Mexico rely on warm oceanic temperatures in order to develop, breakdown over landdevelop, breakdown over land

The Factors Affecting Tropical The Factors Affecting Tropical SystemsSystems

• Main contributing factor to tropical system intensity:Main contributing factor to tropical system intensity: ↓↓ ↓ ↓ Sustainable warm ocean temperatures (Sustainable warm ocean temperatures (LindseyLindsey 2006) 2006)

• Most likely cause for an increase in warm ocean Most likely cause for an increase in warm ocean temperature → global warming temperature → global warming

• Global warming → the increase in global surface Global warming → the increase in global surface temperature due to trapped thermal heat from the temperature due to trapped thermal heat from the sun and trapped heat radiated from Earth sun and trapped heat radiated from Earth

What Affects Sea Surface What Affects Sea Surface TemperatureTemperature

• The trapping of this heat is primarily caused by The trapping of this heat is primarily caused by greenhouse gas emissionsgreenhouse gas emissions

• The increase and decrease of greenhouse gases over The increase and decrease of greenhouse gases over time → shown to correlate with increases and decreases time → shown to correlate with increases and decreases in global temperaturein global temperature

• The process of global warming → nearly direct effect The process of global warming → nearly direct effect on oceanic surface temperatures on oceanic surface temperatures (Anthes 2006)(Anthes 2006)

•Temperature - the definitive ingredient in the formationTemperature - the definitive ingredient in the formationof tropical storms of tropical storms

Interactions between the Ocean Interactions between the Ocean and the Atmosphereand the Atmosphere

Figure 2: Ocean and Climate, Physical Coupling with the Atmosphere

(Herring 2006)

• Physical Physical relationships:relationships:

– Precipitation from Precipitation from atmospheric moisture cycles atmospheric moisture cycles from the ocean through the from the ocean through the atmosphere atmosphere

– Sea surface temperature and Sea surface temperature and other heat exchanges other heat exchanges (condensation) from (condensation) from atmospheric conditionsatmospheric conditions

– Also development of surface Also development of surface winds and sustainable winds winds and sustainable winds through atmospheric through atmospheric conditions conditions

Interactions between the Ocean Interactions between the Ocean and the Atmosphere Continuedand the Atmosphere Continued

• Chemical relationships:Chemical relationships:– Chemical interactions with Chemical interactions with

Greenhouse gases – primarily the Greenhouse gases – primarily the exchange of water vapor and carbon exchange of water vapor and carbon dioxide dioxide

– Also these interactions compliment the Also these interactions compliment the physical interactions between oceans physical interactions between oceans and the atmosphere, such as heat and the atmosphere, such as heat exchangeexchange

– Much of the heat that escapes the Much of the heat that escapes the ocean is in the form of water vapor; ocean is in the form of water vapor; the most significant greenhouse gas the most significant greenhouse gas ((HerringHerring 2006) 2006)

– A fairly direct relationship exists A fairly direct relationship exists between the presence of greenhouse between the presence of greenhouse gases and the physical processes that gases and the physical processes that occur in the atmosphere and oceansoccur in the atmosphere and oceans

Figure 3: Oceans and Climate: Chemical Coupling with the Atmosphere

(Herring 2006)

Atmospheric/Oceanic Processes Atmospheric/Oceanic Processes Resulting from Natural CyclesResulting from Natural Cycles

• The chemical relationship between the atmosphere and The chemical relationship between the atmosphere and ocean is constructed of many natural cycles:ocean is constructed of many natural cycles:

• (Global) carbon cycle (Global) carbon cycle • Water cycle Water cycle • Nitrogen cycle Nitrogen cycle

• The global carbon cycle: The global carbon cycle: • Exchange of carbon material (organic carbon material and Exchange of carbon material (organic carbon material and

inorganic CO2 gases) inorganic CO2 gases) • Pathway: travels through the atmosphere, oceans, terrestrial Pathway: travels through the atmosphere, oceans, terrestrial

(land) interactions, back into atmosphere (land) interactions, back into atmosphere (Fung 2005)(Fung 2005)

The Global Carbon CycleThe Global Carbon Cycle

• Stella Modeling of Stella Modeling of Carbon Carbon interactions within interactions within atmospheric, atmospheric, oceanic, and oceanic, and terrestrial regionsterrestrial regions

• Organic Process Organic Process (mostly occurring (mostly occurring in the terrestrial in the terrestrial region) simplified region) simplified with the modelwith the model

Oceanic CarbonTerrestrial Carbon

f rom Soils and Plants

Atmospheric Carbon

Oceanic Uptake

Oceanic Release

Plant and Soil Respiration

Photosy nthesis

Fossil Fuels and Land UseFrom Humans

Unknown Sink

Atmosphere CO2 in ppm

N Hemisphere

Seasons

Aspects of the Inorganic Carbon Aspects of the Inorganic Carbon CycleCycle

• The inorganic carbon cycle The inorganic carbon cycle -- a main participant in the a main participant in the interactions that contribute to tropical system interactions that contribute to tropical system developmentdevelopment

• Any increase in atmospheric CO2 levels generally Any increase in atmospheric CO2 levels generally leads to an increase in absorption of CO2 in ocean leads to an increase in absorption of CO2 in ocean waters through the inorganic carbon cycle waters through the inorganic carbon cycle (Fung (Fung 2006)2006)

• Small (natural) increases in CO2 concentration in Small (natural) increases in CO2 concentration in ocean waters → does not affect the cycle to a ocean waters → does not affect the cycle to a significant degree significant degree

The Human Influence of the The Human Influence of the Inorganic Carbon Cycle Inorganic Carbon Cycle

• Large increases in CO2 concentration in the ocean Large increases in CO2 concentration in the ocean waters -amplification of the inorganic carbon cyclewaters -amplification of the inorganic carbon cycle

• Inorganic carbon constantly re-circulates through Inorganic carbon constantly re-circulates through atmospheric/oceanic/terrestrial regionsatmospheric/oceanic/terrestrial regions

• No substantial amounts of inorganic carbon material is No substantial amounts of inorganic carbon material is lost through the systemlost through the system

• Every part of system is affected by an atmospheric Every part of system is affected by an atmospheric change of Carbonchange of Carbon

• Linking the human alterations of the inorganic Linking the human alterations of the inorganic carbon cycle to increasing sea surface temperaturecarbon cycle to increasing sea surface temperature

Conclusions: How These Elements of Conclusions: How These Elements of Global Warming Affect Tropical System Global Warming Affect Tropical System

IntensityIntensity

• Summary of Concepts:Summary of Concepts: • Tropical storms form when conditions are met: medium Tropical storms form when conditions are met: medium

winds, pressure, and warm sea surface temperatureswinds, pressure, and warm sea surface temperatures

• Warm sea surface temperature most important factor in Warm sea surface temperature most important factor in development and intensity of tropical system intensitydevelopment and intensity of tropical system intensity

• Warm sea surface temperature influenced by the Warm sea surface temperature influenced by the greenhouse effect and greenhouse gasses, increasing greenhouse effect and greenhouse gasses, increasing over the last centuryover the last century

Conclusions Continued Conclusions Continued • Summary of Concepts Continued:Summary of Concepts Continued:

• Increase in Greenhouse gases primarily Increase in Greenhouse gases primarily due to unnatural increasing carbon rates due to unnatural increasing carbon rates in the atmospherein the atmosphere

• Human alteration of amounts of Human alteration of amounts of atmospheric carbon → impact on carbon atmospheric carbon → impact on carbon cycle cycle

• Carbon cycle then influences sea surface Carbon cycle then influences sea surface temperature → general increase in temperature → general increase in tropical system intensitytropical system intensity

• If tropical systems intensify as predicted If tropical systems intensify as predicted then a modification to the Saffir-Simpson then a modification to the Saffir-Simpson will be warrantedwill be warranted

Figure 4: Monthly Mean Surface Temperatures v. Maximum Wind Speeds for Atlantic Tropical

Systems(Emmanuel 1991)

Predicted Atmospheric Carbon Levels – Predicted Atmospheric Carbon Levels – 1995 - 20951995 - 2095

• Graph displays the predicted atmospheric carbon levels Graph displays the predicted atmospheric carbon levels from 1995 – 2095 using basic carbon cycle (including both from 1995 – 2095 using basic carbon cycle (including both organic and inorganic carbon) Stella modeling organic and inorganic carbon) Stella modeling

• Initial Value for amount of CO2 in atmosphere: 350 ppmInitial Value for amount of CO2 in atmosphere: 350 ppm• Projected Value in one hundred years: ~ 600 ppm!Projected Value in one hundred years: ~ 600 ppm!

5:45 PM Mon, Dec 04, 2006

Atmospheric CO2 Concentrations in the Atmosphere with a Simple Global Carbon Cycle

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1995.00 2020.00 2045.00 2070.00 2095.00

Years

1:

1:

1:

350

500

650

1: Atmosphere CO2 in ppm

1

1

1

1

What Can We Do to Help?What Can We Do to Help?• The most important step in solving the problem is The most important step in solving the problem is

becoming educationally aware of the situation:becoming educationally aware of the situation:

– Understand how this problem is a global issue, one shared by Understand how this problem is a global issue, one shared by ALLALL

– Recognize your individual contribution to the issue, and some Recognize your individual contribution to the issue, and some methods to become “carbon neutral’methods to become “carbon neutral’

– Providing Information to U.S. Citizens of the Gulf Coast Region:Providing Information to U.S. Citizens of the Gulf Coast Region:

• Better preparations for tropical systems Better preparations for tropical systems • Suggestions for improving defenses against such stormsSuggestions for improving defenses against such storms

Works CitedWorks Cited

Anthes, R.A., Corell, R.W., Holland, G., Hurrell, J.W., Maccracken, M.C., and 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 Trenberth, K.E. 2006. Hurricanes and Global Warming - Potential Linkages and Consequences. Bull Am Meteorol Soc 87. 5:623-631. Consequences. Bull Am Meteorol Soc 87. 5:623-631.

Emanuel, K A. 1991. Comments on Carbon Dioxide and Hurricanes: Implications Emanuel, K A. 1991. Comments on Carbon Dioxide and Hurricanes: Implications of Northern Hemispheric Warming for Atlantic/Caribbean Storms. Meteorol. of Northern Hemispheric Warming for Atlantic/Caribbean Storms. Meteorol. Atmos. Phys. 47: 83-84. Atmos. Phys. 47: 83-84.

Fung, I.Y., Doney, S.C., Lindsay K., and John J. 2005. Evolution of Carbon Sinks in 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 a Changing Climate. Proceedings of the National Academy of Sciences of the United States of America. PNAS 102. 32: 11201-11206. United States of America. PNAS 102. 32: 11201-11206.

Herring, David. "Ocean & Climate." 2006. NASA Earth Observatory. Herring, David. "Ocean & Climate." 2006. NASA Earth Observatory. <http://earthobservatory.nasa.gov/Library/OceanClimate/oceanclimate.html> <http://earthobservatory.nasa.gov/Library/OceanClimate/oceanclimate.html> (24 October 2006)(24 October 2006)

Works Cited ContinuedWorks Cited Continued

Lindsey, Rebecca. "Hurricanes: the Greatest Storms on Earth." 2006. NASA Earth Lindsey, Rebecca. "Hurricanes: the Greatest Storms on Earth." 2006. NASA Earth Observatory. Observatory. <htttp://earthobservatory.nasa.gov/Library/Hurricanes/hurricanes_1.html> <htttp://earthobservatory.nasa.gov/Library/Hurricanes/hurricanes_1.html> (24 October 2006)(24 October 2006)

Rahmstorf, S. 2000. The Thermohaline Ocean Circulation: A System with Rahmstorf, S. 2000. The Thermohaline Ocean Circulation: A System with dangerous Thresholds. Climatic Changedangerous Thresholds. Climatic Change 4646: : 247–256.247–256.

““Tropical cyclone: Life Cycle of a North Atlantic hurricane." Encyclopedia Tropical cyclone: Life Cycle of a North Atlantic hurricane." Encyclopedia Britannica Online. <http://www.britannica.com/eb/art-75358> Britannica Online. <http://www.britannica.com/eb/art-75358> (24 October 2006)(24 October 2006)

Webster, P.J., G.J. Holland, J.A. Curry, and H.R. Chang. 2005. Changes in Tropical 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 Cyclone Number, Duration, and Intensity in a Warming Environment. Science Magazine 309: 1844-1846.Magazine 309: 1844-1846.