Title

Southern Murray Darling Basin - DEM 

Time period

2001-04-012001-08-01 

Horizontal Accuracy

0.5m  

Vertical Accuracy

0.15m  

Code

MGA Zone 55 GDA94 

Title

ESRI Ascii 

Topic category

• Elevation

Use limitation

Departmental 

Classification

Limited Distribution  

Description

The 1m product has been derived from raw LiDAR data (XYZ Intensity ASCII¿s) collected by the Southern Murray Darling Basin Commission. The DEM and intensity products have been created by converting the ASCII files to a point coverage. A TIN is then generated from the points and converted to a DEM. Due to the size and quantity of data being processed a 2km x 2km tile index system was used to process all data (first and last return) for the 1m pixel products. 

Classification

Unclassified  

Attribute Quality

Positional Accuracy

Conceptual Consistency

Comments

The consistency of the DEM¿s is mainly conditioned by the consistency of the input data set (raw LiDAR data). Errors within the raw data will have an impact on the resultant DEM. Consistency during processing for 1m and 10m DEM¿s and Intensity, included ensuring that there was sufficient buffering to minimise `edge effects¿ between 2km x 2km tiles when they are mosaiced to create a seamless terrain model. 

Missing Data

Comments

1m DEMs have been created for the whole Southern Murray Darling Basin study area, though owing to errors during the data capture process, there are sections of some 2km x 2km tiles where the DEM generation has not been entirely successful in terms of creating continuous terrain. Errors such as swathe overlaps (possibly due to calibration errors between flight paths), missing data (insufficient pulses returning to the recording device or errors during data capture) and `waves¿ (possibly owing to turbulence) cause visible artefacts in the terrain model. These errors can only be rectified through future LiDAR data capture flights over the study area. 

Excess Data

Platform Type

Aerial  

Assembly

Single  

Tile Size

2 km  

Raster Type

DEM  

X Pixel Resolution (cm)

1cm  

Y Pixel Resolution (cm)

1cm  

Seamlessness

Full  

Number of Bands

0 

Band List

Not Entered  

Resampling Kernel

Not Entered  

Rectification Type

Not Entered  

Platform Name

Not Entered  

DEM Creator

CIP