The GIS Weasel An Interface for the Treatment Of Spatial Information In Modeling Roland Viger, Steven Markstrom, George Leavesley

The GIS Weasel What is the GIS Weasel? A Stand-alone Workstation ArcInfo Application –Map and menu driven –Minimal GIS expertise needed to operate »“bring GIS to the modeler” –Runs anywhere Workstation ArcInfo does –Arc Macro Language (AML), C code, shell scripts –Open source Useful for: –Delineating spatial features relevant to modeling –Characterizing spatial features –Parameterizing spatial features

The GIS Weasel What is the GIS Weasel? (cont.) Designed to complement a variety of physical process models –Lumped parameter models –Distributed parameter models Part of the Modular Modeling System Project –Framework for assembling physical process algorithms (modules) –Allows rapid assembly sets of algorithms optimized for constraints of modeling application at hand »Data availability, accuracy, resolution, modeling scale, etc –Allows development & comparison of alternative algorithms –

The GIS Weasel What isn’t the GIS Weasel? A model A modeling system A DEM manufacturing or reconditioning tool An NHD processing or conflation tool

The GIS Weasel What does the GIS Weasel try to do? Standard Tasks: application of well known/accepted methodologies Automate tasks typical to hydrologic modeling –Fill DEM pits –Derive Flow Direction (D8) –Derive Flow Accumulation –Delineate Area-Of-Interest (AOI) –Derive Slope, Aspect –Reclassify Slope, Aspect, Elevation –Extract a drainage network from the DEM Hopefully NHD, NED, NED-H, and WBD will reduce most of these tasks to “query” and “download” activities

The GIS Weasel What does the GIS Weasel try to do? (cont) Non-Standard Tasks: the buzzwords Iteration User-Data Interaction Vertical Integration –Leverage it in source data (NHD,NED,NED-H,WBD) –Generate new relationships with derived data, as needed by model

The GIS Weasel What does the GIS Weasel try to do? (cont) Non-Standard Tasks: the concepts Hydrologic Response Units (HRUs), after Leavesley –Land surface areas of homogenous hydrologic character Alternative specializations of this concept –Erosion Response Units –Chemical Response Units –Et cetera Genericized to Modeling Response Units (MRUs) –Any type of spatial feature to be modeled

The GIS Weasel What does the GIS Weasel try to do? (cont) Delineate types of MRUs: Can help define and describe features like: –Overland flow planes –Links in a drainage network –Reservoirs/Dams Not limited to single type of point, line, or polygon feature –For instance, several types of polygon features »Overland flow planes & groundwater reservoirs Not limited to just vector or raster representation –Usually try to use both for increased flexibility

The GIS Weasel What does the GIS Weasel try to do? (cont) Delineate types of MRUs: Provide relevant definitions for MRUs –Generation and maintenance of simple data models for general and specific MRUs –Enforcing consistency between types of MRUs, where necessary Provide relevant sets of tools for the delineation and modification of MRUs Looking to new technology to aid in both of these efforts –Current techniques inconvenient to maintain and integrate with standard geoprocessing functions

The GIS Weasel What does the GIS Weasel try to do? (cont) Characterize MRUs: Provide tools to query and analyze MRUs –information on which to base further MRU modification Standard Suite –histograms, hypsometric curves, cell query, logic query

The GIS Weasel What does the GIS Weasel try to do? (cont) Parameterize MRUs: Generate output for use in a variety of models –Precipitation-Runoff Modeling System (PRMS) –TOPMODEL –Climate Data Distribution Models –Flood Frequency Analysis Models –Many generic parameters Hope to enlarge library of parameterization methodologies –Largely dictated by user demand

The GIS Weasel What does the GIS Weasel try to do? (cont) Parameterize MRUs: Standard Outputs –Plain columnar, space delimited ASCII files »easy to reformat –MMS format parameter files –Shapefiles Looking to alternatives in near future –XML –ESRI geodatabases »Leverage Arc API for geoprocessing, SQL and Simple Feature APIs for query and integration with modeling –Other open data formats

` Goals for Future Enable tighter integration with modeling system –MMS II: The Object Modeling System (OMS) »Pure Java and XML »Able to integrate native code, »Including calls to to COM objects (hopefully) –Development of GIS modules for OMS

The GIS Weasel Contact Information: Roland Viger

The GIS Weasel Demonstration

The GIS Weasel Position (lat/long, projected) Area (various units) Orientation (slope, aspect) Currently Available Parameterization Methodologies Elevation (various units) Derived Category Maps (Radiation Planes) Based On DEMs:

The GIS Weasel Soil (STATSGO/SSURGO) Vegetation Character/Behaviour (type, density, leaf loss, interception, transmissivity) Land Cover Character (impermeability, dominant usage) Currently Available Parameterization Methodologies Climate Data Adjustment Factors Snow Factors Evapotranspiration (Jenson-Haise coef) Based On Ancillary Data:

The GIS Weasel Overlay (intersection, area, weightings) Line/Network Type Description (downstream, length, order- strahler,order-shreve, velocity, travel time, from/to nodes) Association between features (poly2point, poly2poly, poly2stream) Generic Statistics (mean, median, dominant category, reclassification, et cetera) Currently Available Parameterization Methodologies Based On Topology:

The GIS Weasel TOPMODEL Sub-Catchment Map Channel Routing Increments Percent of Upstream Area Distance to Catchment Outlet Topgraphic Index (the “loni”) Loni Category Numbers Loni Category Values Percent Area w/in each Loni Category Currently Available Parameterization Methodologies *Soils (change in hydraulic conductivity with depth, etc) -Due to extreme model sensitivity to this information and limited data accuracy, typically calibrated

The GIS Weasel HSPF BASINSOFT User Driven -Agriculture -Climate -Subsurface/Groundwater Potential Development of Parameterization Methodologies