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Layer: cumb_etwi.tif (ID: 4)

Parent Layer: Cumberland

Name: cumb_etwi.tif

Display Field:

Type: Raster Layer

Geometry Type: null

Description: GIS raster dataset displaying Topographic Wetness Index (TWI) for east Cumberland County, PA. This TWI raster was derived from the 2006-08 PAMAP LiDAR DEM data. The TauDEM extension (D-Infinity tools) for ArcMap was used to create flow direction, slope, and contributing area rasters. TWI was then calculated using the following equation: Ln (Contributing Area/Slope). The methodology was described by Cody Fink in his 2013 thesis entitled Dynamic Soil Property Change in Response to Natural Gas Development in Pennsylvania. TWI results in a dimesionless raster and should be displayed using a red (low values representing no flow) to blue (high, representing high probability flowpaths) color gradient. TWI results vary depending on raster size and analysis options so value thresholds for probability-based overland flowpaths for water should be field verified.

Definition Expression: N/A

Copyright Text: Jamie Shallenberger, SRBC, and Cody M. Fink.

Default Visibility: true

MaxRecordCount: 0

Supported Query Formats: JSON, AMF

Min Scale: 0

Max Scale: 0

Supports Advanced Queries: false

Supports Statistics: false

Has Labels: false

Can Modify Layer: false

Can Scale Symbols: false

Use Standardized Queries: true

Drawing Info: Advanced Query Capabilities:
HasZ: false

HasM: false

Has Attachments: false

HTML Popup Type: esriServerHTMLPopupTypeNone

Type ID Field: null

Fields: None

Supported Operations:   Query   Generate Renderer   Return Updates