cee 795 water resources modeling and gis
DESCRIPTION
CEE 795 Water Resources Modeling and GIS. Session #1 (some material from Dr. David Maidment, University of Texas) January 18, 2006 Learning Objectives: Outline the various types of models that can be integrated with GIS Describe the geospatial database of hydrologic features - PowerPoint PPT PresentationTRANSCRIPT
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CEE 795Water Resources Modeling and GIS
Session #1(some material from Dr. David Maidment, University of Texas)
January 18, 2006Learning Objectives:• Outline the various types of models that can be integrated with GIS• Describe the geospatial database of hydrologic features • Outline the Arc Hydro data model• Demonstrate the use of curved earth and a flat map projections
Handouts: Assignments:Get SCR login accounts
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Water Resources Modeling and GIS: Session 1
• Water Resource Models and GIS
• Geospatial database of hydrologic features
• Arc Hydro data model
• Curved earth and a flat map
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GIS and Hydraulic Models
• HEC Geo-RAS• Used for Pre and Post
processing of data from HEC-River Analysis System (RAS)
• Open Channel flow model
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GIS and Hydrologic Models• Automated
Geospatial Watershed AssessmentTool (AGWA)
1992 NALC Hillshade DEM STATSGO
ForestOak WoodlandsMesquite WoodlandsGrasslandsDesertscrubRiparianAgricultureUrbanWaterBarren / Clouds
Land CoverForestOak WoodlandsMesquite WoodlandsGrasslandsDesertscrubRiparianAgricultureUrbanWaterBarren / Clouds
Land Cover
0 5 10 km0 5 10 km
NN
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GIS and Water Distribution Models
• Haestad WaterGEMS
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Water Resources Modeling and GIS: Session 1
• Water Resource Models and GIS
• Geospatial database of hydrologic features
• Arc Hydro data model
• Curved earth and a flat map
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Geographic Data Model
• Conceptual Model – a set of concepts that describe a subject and allow reasoning about it
• Mathematical Model – a conceptual model expressed in symbols and equations
• Data Model – a conceptual model expressed in a data structure (e.g. ascii files, Excel tables, …..)
• Geographic Data Model – a conceptual model for describing and reasoning about the world expressed in a GIS database
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Data Model Data Model based on based on Inventory of Inventory of data layersdata layers
Spatial Data: Vector format
PointPoint - a pair of x and y coordinates(x1,y1)
LineLine - a sequence of points
PolygonPolygon - a closed set of lines
Node
vertex
Vector data are defined spatially:
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Themes or Data Layers
Vector data: point, line or polygon features
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Kissimmee watershed, Florida
Themes
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Attributes of a Selected Feature
Raster and Vector Data
PointPoint
LineLine
PolygonPolygon
VectorVector RasterRaster
Raster data are described by a cell grid, one value per cell
Zone of cells
14http://srtm.usgs.gov/srtmimagegallery/index.html
Santa Barbara, California
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How do we combine these data?
Digital ElevationModels
Watersheds Streams Waterbodies
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An integrated raster-vector
database
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Data Model Based on Behavior
“Follow a drop of water from where it falls on the land, to the stream, and all the way to the ocean.”
R.M. Hirsch, USGS
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Integrating Data Inventory using a Behavioral Model
Relationships betweenobjects linked by tracing pathof water movement
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Water Resources Modeling and GIS: Session 1
• Water Resource Models and GIS
• Geospatial database of hydrologic features
• Arc Hydro data model
• Curved earth and a flat map
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Arc Hydro: GIS for Water ResourcesPublished by ESRI Press
The Arc Hydro data model andapplication tools are in the publicdomain
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Arc Hydro — Hydrography
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Arc Hydro — Hydrology
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Flow
Time
Time Series
Hydrography
Hydro Network
Channel System
Drainage System
Arc Hydro Components
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Hydrologic Information System
Analysis, Modeling, Decision Making
Arc Hydro Geodatabase
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Nexrad Radar Rainfall Map
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Nexrad Map to Flood Map in Model Builder
FLOODPLAIN MAP
Flood map as output
Nexrad map as input
Model for flood flow
Model for flood
depth
HMS
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Water Resources Modeling and GIS: Session 1
• Water Resource Models and GIS
• Geospatial database of hydrologic features
• Arc Hydro data model
• Curved earth and a flat map
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Origin of Geographic Coordinates
(0,0)Equator
Prime Meridian
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Latitude and Longitude
Longitude line (Meridian)N
S
W E
Range: 180ºW - 0º - 180ºE
Latitude line (Parallel)N
S
W E
Range: 90ºS - 0º - 90ºN(0ºN, 0ºE)
Equator, Prime Meridian
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Latitude and Longitude in North America
90 W120 W 60 W
30 N
0 N
60 N
Austin: (30°N, 98°W)
Logan:(42°N, 112°W)
Map Projection
Curved EarthGeographic coordinates: ,
(Latitude & Longitude)
Flat Map Cartesian coordinates: x,y
(Easting & Northing)
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Earth to Globe to Map
Representative Fraction
Globe distanceEarth distance
=
Map Scale: Map Projection:
Scale Factor
Map distanceGlobe distance
=
(e.g. 1:24,000) (e.g. 0.9996)
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Coordinate Systems
(o,o)(xo,yo)
X
Y
Origin
A planar coordinate system is defined by a pairof orthogonal (x,y) axes drawn through an origin