Presentation on theme: "GIS Coordination on a Statewide Scale using a Common Toolset Application Marshall Flynn IT/GIS Manager Tampa Bay Regional Planning Council Pinellas Park,"— Presentation transcript:
GIS Coordination on a Statewide Scale using a Common Toolset Application Marshall Flynn IT/GIS Manager Tampa Bay Regional Planning Council Pinellas Park, FL
Florida Statewide Regional Evacuation Study Update Program GIS Technology Drives the Data & the Analysis Each Region on its Own in the Past First Statewide Comprehensive Effort Like This Ever Product is for State of Florida with Regions as Sections Compatibility, Structure, and Formatting are Key Elements All ESRI 9.3+ with Spatial Analyst Common Map Templates Common Symbology
Evacuation Zones are the Product Used Most and Seen Most by the Public, and Used for Evacuation Transportation Modeling Component Surge Zones are used as a basis to delineate those Evacuation Zones Consistent Methodology and Data Essential (11 Regions = 1 State) State Chose NHC SLOSH Model for Surge Inundation SRES Program uses SIM* for Post-Processing Surge Zone Creation Evacuation Zones Then Derived From Surge Zones by County EM Dept. * Surge Inundation Model Tropical Storm System Surge Zone Component
Why is This Evacuation Update Such a Good Idea? Many Regions Have not Updated Their Evacuation Data for Years Processing is 90% automated Computers 6X Faster than last time (on average) Available Base Data is so Much Better!
Light Detection and Ranging LiDAR Sea, Lake, Overland Surge from Hurricanes SLOSH Models Regional Evacuation Studies Analyses Vulnerability Behavioral Demographics Transportation Storm Surge Zones Begun FY 06-07 Complete FY 09-10 Data Processing Development for SLOSH Begun FY 06-07 Complete FY 08-09 Begun FY 06-07 Complete FY 08-09 Contractors National Hurricane Center Regional Planning Councils Regional Planning Councils Begun FY 08-09 Complete FY 09-10 Begun FY 08-09 Complete FY 09-10 SRES Process Components FY 09-10
Sea, Lake, and Overland Surge from Hurricanes A computerized model developed by the National Weather Service (NWS) to estimate storm surge heights and winds resulting from historical, hypothetical, or predicted hurricanes. What is SLOSH?
What is Storm Surge? NAVD88 STORM SURGE is the increase in water level due to a storm (hurricane /tropical storm / high winds).
DEFINITIONS: STORM SURGE is the increase in water level due to a storm (hurricane / tropical storm / high winds). STORM TIDE is the total water level during a storm = Astro Tide + STORM SURGE + Rainfall Runoff + Anomaly = Astro Tide + STORM SURGE + Rainfall Runoff + Anomaly
SLOSH Hurricane Storm Surge Model Solves shallow water equations Orthogonal curvilinear grid system 2-dimensional (2 ½ dimensional ???)
SLOSH Hurricane Storm Surge Model Overland flooding Sub-grid Features: 1-dimensional flow for rivers and streams barriers cuts between barriers channel flow, with chokes and expansions Increased friction for trees and mangroves
SLOSH Hurricane Storm Surge Model Embedded parametric hurricane wind model Uses a normalized wind profile Solves diff eqn for wind speed and direction (Direction is NOT specified a priori) Uses pressure, not observed wind speed Forward speed incorporated into asymmetry
INPUT TO SLOSH TRACK Positions - latitude & longitude INTENSITY - (pressure drop) SIZE - Radius of maximum wind
SLOSH Hurricane Storm Surge Model Model output: MOM’s and MEOW’s Individual runs – in real time Historical hurricane runs Probabilistic surge forecasts Available in SLOSH display format GIS format (ArcView or MapInfo) Animations (on web)
Creating Surge Zones Data needs to be processed fairly fast Results should be relatively consistent Some RPCs have not done surge models Developed and proven methodology Fairly easy to use SRES Phase II: Surge Zones & Evacuation Zones
Toolset Has its Origin in ArcView 3.2 Using Avenue (2005)
Select your basin area Choose Output Folder Choose Raster Cell Size Tide: Mean or High Calc Model Values Dry (99.9)? Calc Mean, Max & Min of Selected Yes Replace with Min-(0.075*Min) No Replace with SLOSH Value Create Centroids From SLOSH Basin Calc Average of Surrounding SLOSH Grids Iterate Thru Each SLOSH Grid Square Interpolate to Raster using Spline Tension SLOSH Polygon SLOSH Surface Raster DEM Raster Subtract DEM From SLOSH Apply Majority Filter Export to Polygons Initial Surge Polys Per Category Buffer Outside of Sea Polys by 50 Feet Sea/Surge Source Polys Reduce Noise: Absorb Area < 0.25 Acre Dissolve by Value Select by Location Surge That Intersects Buffered Sea Select Surge: Value = 1 Contiguous Surge Polygons Input Data = Green Output Data = Yellow To Cat Layer Combine SRES Surge Tool Category Zone Module
From Zone Module Cat 1 Cat 2 Union Cat plus Next Highest Cat Cat 1_2 Union Cat plus Next Highest Cat Cat 3 Cat 1_3 Union Cat plus Next Highest Cat Cat 4 Cat 1_4 Union Cat plus Next Highest Cat Cat 5 Cat 1_5 Select and Fill Cat Field with Associated Cat Number Add Cat Field Dissolve by Cat Singlepart Apply Defined Symbol Renderer Finished Displayed Surge Creating Surge Composite Shapefile
This is not what the real world is like…… SLOSH grids actually much bigger
Spatial Analyst Works in Raster Format Faster processing large numbers than vector Readily converts back to vector
The previous slide demonstrates the surge heights (which are based on average elevation per grid) in MOM basin with square edges We know that water does not behave like this How do we get a realistic depiction of surge height with respect to the real terrain underneath? –Interpolation of grid heights –Creates a smooth surface for further topographical processing The results allow a realistic depiction of inundation of terrain Modeling MOM Values into Realistic Surge
An area with SLOSH MOMs in their default square basin form. Circled area would be devoid of surge if not interpolated.
You can see how the interpolation hugs the terrain as in real life. That is what you are looking for.
Surge Model Toolset for GIS Processing Updated High Resolution Elevation Data Updated SLOSH Maximum of Maximum Data Aerial Imagery (QA Checks for Data) Water Feature Data for Surge Origination These Are Needed: How Do We Get There?
Shows the relief detail of Digital Elevation, if shaded and shadowed…
Water features do not Create Surge where there is none. They merely allow Contiguous Selection further than Inundation Polygon stopped by Higher Elevation Structures Above Flow. Bridges, Culverts, and Tunnels are Examples of These. Points to Consider:
Surge zone shapefiles from adjoining areas are merged to county level (if needed) They are inspected for smooth transition and anomalies are corrected Then they are inspected and edited to foster a smooth transition within the region The files are used for Storm Tide Atlas and creating preliminary evacuation zones QA/QC and Regional Surge Clean-up
This is a case, generally where older surge covers less inland areas
Why is this? Most likely due to SLOSH basin resolution differences Last basin used (1991) had larger grid cells, so less variation –SLOSH values are now derived from better topography changes Elevation data this time is processed at a 5ft pixel size, which –Has finer scale to catch topography changes (stopping surge) –Picks up more nuances like depressions, which divert flow away There is no hard-fast rule that says the new surge will always be greater at all category levels. –That being said, it does appear that higher categories (4 & 5) have a greater chance at having more inundation