Kirk Sherrill - GIS Specialist Brent Frakes – Geographer Stephani Schupbach – GIS Specialist

1. Inventory & Monitoring Division – GIS Program Travel Time Cost Surface Model (TTCSM) Kirk Sherrill - GIS Specialist Brent Frakes – Geographer StephaniSchupbach – GIS Specialist NRPC – I&M Division – GIS Program Fort Collins, CO George Wright Society Conference GIS Rapid Fire – March, 2011 TTCSM - SOP

2. Inventory & Monitoring Division – GIS Program The TTCSM: • Is a GIS Python Model which: • Calculates travel times from defined point(s) to other locations in an AOI • Dynamic: User and Park Specific • Uses readily available GIS Data • Efficient Field Data Sampling Design and Planning • Packaged as two python scripts • Requiring only basic programming experience • Moderate GIS experience

3. Inventory & Monitoring Division – GIS Program • TTCSM is a linear model which performs: • Cost Surface • Speed Surface • Travel Cost Surface • Travel Time Modeling Inventory & Monitoring Division TTCSM - Schematic

4. Inventory & Monitoring Division – GIS Program • Cost Surface • Represents the amount of travel speed resistance per cell • Generated in a simple overlay manner • Key Steps: • Determine desired input layers and order • Assign Percent of Maximum Travel Speed (PMTS) values for each data layer Inventory & Monitoring Division

5. Inventory & Monitoring Division – GIS Program • Speed Surface • Defines the travel speed (seconds/per meter) per cell • Function: • Road Network Speed • Trail Speed • Hillslope Speed • Trail and Hillslope Speed are defined using Slope values and Tobler’s (1993) equation: Inventory & Monitoring Division Tobler, W. 1993. Three presentations on geographical analysis and modeling. Technical report. 93-1, National center for geographic information and Analysis, University of California, Santa Barbara.

6. Inventory & Monitoring Division – GIS Program • Travel Cost Surface • Final Travel Speed at which movement in a cell occurs. Travel Cost Surface (miles/hour) for ROMO

7. Inventory & Monitoring Division – GIS Program • Final Step: Travel Time Modeling 1. Traditional Cost Distance Modeling • ArcGIS Cost Distance Function • Isotropic Model (treats all directions as equal) Travel times for a TTCSM which used Cost Distance Modeling

8. Inventory & Monitoring Division – GIS Program • Directionality Matters (Anisotropic) – incorporate the influence of Slope • More Realistic User Specific Travel Times (Upslope and Downslope) • 9 Predefined Path Distance Scenarios 2. Path Distance Modeling - ArcGIS Path Distance Function Travel Speed by Slope for five different flat surface walking speeds when using path distance modeling with a “linear” Path Distance Scenario.

9. Inventory & Monitoring Division – GIS Program • Travel Time Modeling Output: - Travel Time Grid(s): Hours, Minutes, or Seconds • Least Cost Paths • One Way or Round Trip Least Cost Paths Travel time least cost paths using an inverse linear path distance travel time model

10. Inventory & Monitoring Division – GIS Program • TTCSM Summary • Dynamic in nature to accommodate user Specific Travel Time Modeling Needs • Outputs Travel Time Grids andTravel Time Least Cost Paths • Runs in the Python Scripting Language on a computer with ArcGIS 9.3 • Working on Arc10 functionality – ESRI Problem between versions! • Scripts and SOP are Downloadable at: • http://nrinfo.nps.gov/ - Search for “TTCSM”

11. Inventory & Monitoring Division – GIS Program • Thanks & Questions?