Lake catchments on Broknes, Larsemann HillsEntry ID: broknes_lake_catchments_gis
Abstract: Catchment boundaries of the the lakes on Broknes, Larsemann Hills.
These catchments were generated using the FLOWDIRECTION and BASINS routines in the GRID module of ArcInfo GIS.
Start Date: 1997-05-06Stop Date: 2001-08-14
Latitude Resolution: 1-10 m
Longitude Resolution: 1-10 m
Quality Data Quality
1 m to 10 m
Definition of lake boundaries is a multi-stage process which can be summarised as follows:
* acquire contour data
* build digital elevation model (DEM)
* generate flow direction model
* generate lake drainage model
The contour data were acquired from aerial photography flown in the austral summer of 1994-5 using a Zeiss UMK metric camera with a lens focal length of 100 mm. It was flown at a height of 1000 metres and is at a scale of 1:10,000.
The DEM was generated using the TOPOGRID cell-based modelling routine in Arc/Info GIS version 7.1.2. A cell size of 5 metres was found to give the best delineation of drainage basins.
Flow direction was determined using the FLOWDIRECTION routine in Arc/Info GRID. This determines the flow direction from each cell to its nearest downslope neighbour.
Drainage basins were determined using the BASIN routine in Arc/Info GRID. The resulting gridded data were then converted to a polygon (vector) coverage of the catchment boundaries using the GRIDPOLY routine. Those drainage basins that included a lake were selected and built as polygons. Minor edits were made to the catchment boundaries to clean up residual polygons formed by individual grid cells. The derived catchment boundaries were manually checked against the original contour data to ensure they conformed to the apparent watersheds.
The automated procedure had most difficulty around the edges of the DEM particularly along the coastline and edge of the ice cap.
Description of the feature - in this case lake catchment boundaries
Unique feature identifier
Name of the lake within the catchment. Names taken from 1: 25000 map (pub. 1991)
Lake number as ascribed in ANARE Research Notes 74 - An atlas of the lakes of the Larsemann Hills
Descrition of the feature - in this case lake catchments
Unique feature identifier
Code generated by ArcInfo GRID - retained when converted from a gridded dataset to polygons
Access Constraints Stored data format: ArcView shapefile
Available format type: ArcView shapefile. Stored as geographicals with a projection file.
Access constraint: ArcView shapefile is available on the web. Conditions apply.
Data are available for download from the URL given below.
Use Constraints This data set conforms to the PICCCBY Attribution License
Data Set Progress
Distribution Media: HTTP
Distribution Size: 435 kb
Distribution Format: shapefiles
Role: TECHNICAL CONTACT
Role: DIF AUTHOR
Phone: +61 2 6272 4615
Fax: +61 2 6272 4687
Email: rupert.summerson at brs.gov.au
Bureau of Rural Sciences PO Box E11
Province or State: Australian Capital Territory
Postal Code: 2604
Extended Metadata Properties
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Creation and Review Dates
DIF Creation Date: 2001-08-30
Last DIF Revision Date: 2014-09-11