Additional Climate Products
|
Climatic Atlas of Australia - Evapotranspiration CD ROM
|
|
The evapotranspiration (ET) CD provides derived
data on both ET limits and actual ET. The three variables mapped are
areal actual, areal potential and point potential evapotranspiration.
For each variable, there is one average annual map and twelve average
monthly maps (39 maps in all).
|
In addition to the 39 evapotranspiration maps the
CD includes mean monthly and mean annual areal actual, areal potential
and point potential evapotranspiration grids.
The grids show the
ET values across Australia and the mean data are based on the standard
30-year period 1961-1990 (see LINEAGE under Metadata for more information).
The CD also includes explanatory text which describes the ET variables
and the method of estimation. The project was carried out jointly
by the Bureau of Meteorology and The University of Melbourne under
the technology transfer program of the Cooperative Research Centre
for Catchment Hydrology. |
Click for sample screen |
| |
|
|
| |
| Product Reference: IDCJMS02.200302 |
Format: CD ROM with Java-based viewer
interface. Windows, MAC & UNIX compatible. The CD includes:
- Monthly and annual gridded data files in ASCII grid-point format (2-dimensional
regular array) with self-describing header;
- Low and high resolution map
images in JPG format;
- Notes and metadata.
|
| Samples: |
Low resolution image file |
| |
High resolution image
file |
| |
Gridded data file (part file only) |
| Metadata: |
|
GEOGRAPHIC EXTENT NAME(S):
|
Australia
|
|
BEGINNING DATE:
|
N/A
|
|
ENDING DATE:
|
N/A
|
|
PROGRESS:
|
Completed
|
|
MAINTENANCE AND UPDATE FREQUENCY:
|
10+ years
|
|
STORED DATA FORMAT:
|
Arc/Info all Australia
|
|
AVAILABLE FORMAT TYPE(S):
|
ASCII grid-point, Arc/Info grid export, 3-column (longitude, latitude, value) text
|
|
ACCESS CONSTRAINTS:
|
Commonwealth of Australia copyright applies (see Copyright Information below)
|
|
LINEAGE:
|
Gridded data were generated using the ANU (Australian National University) 3-D Spline (surface fitting algorithm). As part of the 3-D analysis process a 0.1 degree resolution digital elevation model (DEM) was used. Approximately 700 stations were used in the analysis. All input station data underwent a high degree of quality control before analysis, and conform to WMO (World Meteorological Organisation) standards for data quality. The definitions of Areal Actual, Areal Potential and Point Potential ET are as follows:
Areal Actual ET is the ET that actually takes place, under the condition of existing water supply, from an area so large that the effects of any upwind boundary transitions are negligible and local variations are integrated to an areal average.
Areal Potential ET is the ET that would take place, under the condition of unlimited water supply, from an area so large that the effects of any upwind boundary transitions are negligible and local variations are integrated to an areal average.
Point Potential ET is the ET that would take place, under the condition of unlimited water supply, from an area so small that the local ET effects do not alter local airmass properties. It is assumed that latent and sensible heat transfers within the height of measurement are through convection only.
The above definitions are based on those given by Morton (1983), but we have used the term areal potential ET for Morton's wet-environment ET and the term point potential ET for Morton's potential ET.
Morton, F.I. (1983). Operational estimates of areal evapotranspiration and their significance to the science and practice of hydrology. Journal of Hydrology, 66: 1-76.
|
|
POSITIONAL ACCURACY:
|
Better than 0.05 (approximately 5km) degrees
|
|
ATTRIBUTE ACCURACY:
|
80% of data have an associated quantitative uncertainty of 5%; uncertainty of remainder is within 15%
|
|
LOGICAL CONSISTENCY:
|
N/A
|
|
COMPLETENESS:
|
No missing data
|
|
ADDITIONAL METADATA:
|
Is an adjunct to evaporation maps printed in: Climatic Atlas of Australia
(Australian Government Printing Service, 1975). |
|
ATTRIBUTES
|
Grid/s provides ET values for all Australia on a grid-cell by grid-cell basis
|
|
SCALE/RESOLUTION
|
0.1 degrees (i.e. based on 0.1 x 0.1 degree gridded data)
|
|
SIZE OF DATASETS
|
1-2 Mb per grid
|
|
|
|
