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Boundary Layer Structure in Landfalling Tropical Cyclones William D Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2004 Boundary Layer Structure in Landfalling Tropical Cyclones William D. Maxham Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES BOUNDARY LAYER STRUCTURE IN LANDFALLING TROPICAL CYCLONES By WILLIAM D. MAXHAM A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science Degree Awarded: Fall Semester, 2004 The members of the Committee approve the thesis of William D. Maxham defended on July 19, 2004. ________________________ Paul Ruscher Professor Directing Thesis ________________________ Robert Hart Committee Member ________________________ T. N. Krishnamurti Committee Member Approved: ________________________________________________ Robert Ellingson, Chairperson, Department of Meteorology The Office of Graduate Studies has verified and approved the above named committee members. ii TABLE OF CONTENTS List of Tables ......................................................................................................................... v List of Figures........................................................................................................................ vi Abstract.................................................................................................................................. ix 1. INTRODUCTION ............................................................................................................ 1 Historical Perspective ................................................................................................ 1 Boundary Layer Structure.......................................................................................... 3 2. DATA AND PROCEDURES........................................................................................... 6 Storm History............................................................................................................. 6 Earl................................................................................................................. 6 Dennis ............................................................................................................ 8 Floyd .............................................................................................................. 10 Irene ............................................................................................................... 12 Data Sources .............................................................................................................. 14 Earl................................................................................................................. 13 Dennis ............................................................................................................ 15 Floyd .............................................................................................................. 18 Irene ............................................................................................................... 20 Analysis Procedures................................................................................................... 21 3. RESULTS OF SURFACE ANALYSIS ........................................................................... 24 Introduction................................................................................................................ 24 iii Earl............................................................................................................................. 32 Dennis ........................................................................................................................ 32 ASOS ............................................................................................................. 30 CMAN............................................................................................................ 35 Floyd .......................................................................................................................... 39 ASOS ............................................................................................................. 39 CMAN............................................................................................................ 42 Irene ........................................................................................................................... 46 ASOS ............................................................................................................. 46 CMAN............................................................................................................ 51 Turbulence Dissipation Rates .................................................................................... 57 4. CONCLUSIONS............................................................................................................... 62 Summary.................................................................................................................... 62 Future Work............................................................................................................... 63 APPENDIX............................................................................................................................ 65 BIBLIOGRAPHY.................................................................................................................. 93 BIOGRAPHICAL SKETCH .................................................................................................100 iv LIST OF TABLES 2.1. Best track positions for Hurricane Earl.......................................................................... 8 2.2. Best track positions for Hurricane Dennis..................................................................... 10 2.3. Best track positions for Hurricane Floyd....................................................................... 12 2.4. Best track positions for Hurricane Irene ........................................................................ 13 2.5. Description of surface data set for Earl (TLH) .............................................................. 15 2.6. Cape Hatters (HSE) observations .................................................................................. 16 2.7. Cape Lookout (CLKN7) observations........................................................................... 17 2.8. Wilmington (ILM) observations.................................................................................... 19 2.9. Cape Lookout (CLKN7) observations.......................................................................... 19 2.10. Key West (EYW) observations.................................................................................... 20 2.11. Miami (MIA) observations .......................................................................................... 21 2.12. Sand Key (CSBF1) observations ................................................................................. 21 3.1. Turbulence dissipation rates and their standard deviation for both wind speed records for each CMAN data set................................................. 61 v LIST OF FIGURES 2.1. Enhanced Infrared image of Hurricane Earl as it nears landfall on the Florida panhandle. Image courtesy of http://www.osei.noaa.gov ................ 7 2.2. Hurricane Dennis spinning offshore at 1305 UTC, 4 September Image courtesy of http://www.osei.noaa.gov ................................................ 9 2.3. Hurricane Floyd during landfall on the North Carolina coast 16 September 1999. Image courtesy of http://www.osei.noaa.gov ................................................ 11 2.4. Satellite photograph of Hurricane Irene at 15 October 1257 UTC before landfall on the Florida peninsula. Image courtesy of http://www.osei.noaa.gov ................................................ 13 2.5. Hurricane Earl from NHC best track positions from the time period 2 September at 0600 UTC through 4 September 0600 UTC......................... 15 2.6. Hurricane Dennis’s path from NHC best track positions between 1200 UTC on 30 August and September at 1200 UTC ................................................... 16 2.7. Hurricane Floyd’s (1999) track from best track positions between 14 September 1800 UTC through 18 September 0000 UTC......................... 18 2.8. Hurricane Irene’s (1999) path from best track points between 14 October 0600 (UTC) through 18 October UTC........................................................... 20 3.1. Wind speed observed at Wilmington (ILM) as Floyd approaches ................................ 24 3.2. Wind speeds at ILM during Floyd approach after removal of the first order trend .................................................................................... 25 3.3. Wilmington wind speed trace after removal of trend and subsequently filtered by the high and low pass filters......................................................... 26 3.4. The trace of wind speed after the detrending, application of the filters and subsequent multiplication by the Hann taper.......................................... 27 vi 3.5. Pressure during Earl’s landfall from TLH. Landfall is approximately 9/3 0600 UTC ................................................................................................ 28 3.6. Time series of 1 minute wind speed during the approach and after landfall period of Hurricane Earl
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