a 1 ASCE 7-10 Wind Speed Map Peter J. Vickery Applied Research Associates, Inc Six Forks Road, Suite 600 Raleigh, NC, 27615

a Expanding the Realm of Possibility Summary New Hurricane Simulation Model Windfield Filling (weakening after landfall) Holland B (pressure-wind Relationship) Tracks and pressures (Landfall location and intensity) Results in Lower Design Wind Speeds Moving to strength wind speed map (wind load factor = 1 for strength design, 0.63 for ASD) Strength map corresponds to 700 year RP ASCE 7-05 Equivalent Map = V 700 /√1.6 Cat III and IV structures use 1700 year RP winds Cat I structures use 300 year RP winds 2

a Expanding the Realm of Possibility V 700 /√1.6 3

a Expanding the Realm of Possibility V 700 /√1.6 4  ASCE 7-05  ASCE 7-10 Equivalent

a Expanding the Realm of Possibility 700 Year Return Period Winds 5

a Expanding the Realm of Possibility 700 Year Return Period Winds 6

a Expanding the Realm of Possibility 1700 Year Return Period Winds 7

a Expanding the Realm of Possibility Simulation Methodology 8

a Expanding the Realm of Possibility Additional Data in New Model 9

a Expanding the Realm of Possibility Landfall Pressures 10

a Expanding the Realm of Possibility Landfall Pressures 11

a Expanding the Realm of Possibility Coastal Segments 12

a Expanding the Realm of Possibility Landfall Pressures 13

a Expanding the Realm of Possibility Landfall Pressures 14

a Expanding the Realm of Possibility Landfall Pressure 15

a Expanding the Realm of Possibility 2008 Model vs Model 16

a Expanding the Realm of Possibility Simulated vs. Historical Maximum Wind Speeds 17

a Expanding the Realm of Possibility Simulated vs. Historical Maximum Wind Speeds 18

a Expanding the Realm of Possibility Simulated vs. Historical Maximum Wind Speeds 19

a Expanding the Realm of Possibility Simulated vs. Historical Maximum Wind Speeds 20

a Expanding the Realm of Possibility Landfall Pressures vs. RP 21

a Expanding the Realm of Possibility Landfall Intensity (by Pressure) 22

a Expanding the Realm of Possibility QUESTION: If the new model produces more intense hurricanes (defined by pressure) than the old model, why have the design wind speeds gone down? 23

a Expanding the Realm of Possibility ANSWER: Because of the New Model for the Holland B Parameter 24

a Expanding the Realm of Possibility What is B? 25

a Expanding the Realm of Possibility What is B? 26

a Expanding the Realm of Possibility What is B? 27

a Expanding the Realm of Possibility Statistical Model for Holland B Parameter 28

a Expanding the Realm of Possibility Holland B Pressure Fits 29

a Expanding the Realm of Possibility B Parameter 30

a Expanding the Realm of Possibility Statistical Model for B 31

a Expanding the Realm of Possibility Holland B from Wind Field Analyses 32

a Expanding the Realm of Possibility Mean B at Land Fall (old vs. new models 33

a Expanding the Realm of Possibility Effect of B on Predicted Wind Speeds 34

a Expanding the Realm of Possibility Effect of B on Predicted Wind Speeds 35

a Expanding the Realm of Possibility Summary New model produces more landfall intense hurricanes by pressure than the model used to develop ASCE 7, yet results in lower wind speeds. Additional flight level data and improved statistical model for B resulted in lower ~10% estimates of the Holland B parameter. In some areas (e.g. Florida Panhandle) the new model produces fewer land falling strong hurricanes, and hence wind speeds are lower than associated with the reduction of B alone. 36

a Expanding the Realm of Possibility Windborne Debris Region Current Standard V > 120 or 110 within one mile of coast Exact Mapping (new 700 year map) 120√1.6=152~ √1.6=139~140 New WBDR is intended to mimic current standard, pending new research V > 140 or 130 within one mile of coast Results in less area within WBD Region that the existing standard 37

a Expanding the Realm of Possibility Wind Borne Debris Region 38