The GIS Weasel - An Interface for the Development of Spatial Parameters for Physical Process Modeling
Entry ID: USGS_GIS_WEASEL
Abstract: The GIS Weasel is a map and Graphical User Interface (GUI) driven tool that has
been developed as an aid to modelers in the delineation, characterization, and
parameterization of Modeling Response Units (MRUs) for use in distributed or
lumped parameter physical process models. The term MRU is intended to be a
generic reference to the spatial feature type or types that a ... model needs to
have descriptions of. There is no fixed methodology for the delineation of MRUs
in the GIS Weasel. In surface water modeling applications, MRUs are commonly
defined as land surfaces that sub-divide an Area Of Interest (AOI), such as a
watershed, to reflect a model's treatment of spatially distributed
characteristics. MRUs can be homogeneous or heterogeneous with respect to some
or all of these characteristics. MRUs generic spatial features
The interface does not require user expertise in geographic information systems
(GIS). The user does need knowledge of how the model will use the output from
the GIS Weasel. The GIS Weasel uses Workstation ArcInfo 8.0.2, the Grid
extension, and the Arc Macro Language (AML), as well as scripts, and C
subroutines. The GIS Weasel will run on all platforms that Workstation ArcInfo
runs (i.e. numerous flavors of Unix and Microsoft Windows).
The GIS Weasel requires as input an ArcInfo grid of some topographical
description of the AOI. This is normally a digital elevation model, but can be
the surface of a ground water table or any other data that flow direction can
be resolved from. The user may select the AOI from a set of watersheds that can
be automatically delineated from the topographical input, based on ridges,
define their own drainage area based on an interactively specified watershed
outlet point, or use a previously created GRID or coverage. This last option is
most useful for AOIs that are not based on topography.
The AOI map serves as the first version of an MRU map. The user is then able to
use any combination of the GIS Weasel's tool set to create one or more maps
that parameters will be derived from. These tools easily integrate other
similarly formatted data sets. Once the spatial feature maps have been
prepared, then the GIS Weasel's many parameterization routines can be used to
create descriptions of each element in each of the user's created maps. Over
100 parameterization routines currently exist, generating information about
shape, area, and topological association with other features of the same or
different maps, as well many types of information based on ancillary data
layers such as soil and vegetation properties.
[Summary provided by the USGS.]
ISO Topic Category
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Creation and Review Dates