OVERSEAS TRAVEL REPORT
RADARSAT Symposium
Montreal, Canada - 13 -15 October 1998
George Cresswell
CSIRO Marine Research
I attended the final RADARSAT symposium in Montreal October 13-15. Roughly 180 papers were presented. I reported on the project that Paul Tildesley and I have had with the Canadian Space Agency. As part of the project we acquired 22 RADARSAT scenes of Australian and adjacent seas. These were provided for free; the market cost is about US$3K each.
The partners in the RADARSAT venture are the Canadian Space Agency, NASA, and Radarsat International.
The Synthetic Aperture Radar on the satellite has a resolution of 10-100 m, depending upon the operating mode that is chosen. A standard scene is 100 km across; others range from 50-500 km.
RADARSAT has a wide range of applications: forestry, glaciology, geology, land use, crops, soil moisture, surveillance, oceanography, etc. It can pick up a dirt road in a forest; shrimp ponds in SE Asia; banana plantations in central America; mangrove distributions in Asia; ancient wadis and drainage networks in Sudan; Agent Orange effects in Vietnam; sea ice; and the 40 cm displacement of the surface of a volcano on the island of La Reunion (using the satellite's interferometer capability).
The satellite has mapped all the land surface of the earth, down to and including the South Pole - all this through cloud. The present station and runway could be seen at the South Pole. This was interesting enough, but beneath it could be seen the old station and old runway. The composite image of Antarctica revealed the ice drainage basins and the equivalent of watersheds.
>From Australia, Anthony Milne and Geoff Horn of UNSW presented a paper on wetland inundation patterns in Kakadu World Heritage Area.
For oceanography RADARSAT works extremely well for internal wave studies and there was a good paper (Ming-K. Hsu and Antony K. Liu, NASA) showing wave formation on a shelf north of the Philippines as depressions of the thermocline; their propagation westward across the South China Sea to the China shelf and, when the lower layer was thinner than the surface layer, a conversion to troughs in the thermocline. The waves split around an island and then rejoined after passing it.
RADARSAT is very exciting for its ability to detect oil seeps and this is revealing new reserves in the Gulf of Mexico and along the Brazilian coast, where a CRC-equivalent has been set up in rapid time there to take advantage of the opportunities (F.P. d Miranda and C.M. Bentz, Petrobras). There is a window of wind speed that works - too little or too much and the seeps don't show against the background.
The Japanese used RADARSAT to coordinate efforts to manage an oil spill. Data were delivered electronically by the Canadians in, on average, 3 1/2 hours after the satellite passes. 46 scenes were delivered over a six-week period.
The wind speed window mentioned above was a feature of our work as well: unless oceanographic features were very strong they were masked by wind effects. So our best scenes were from the tropics rather than temperate Australia.
I used our 4 Sepik River plume RADARSAT scenes along with in situ data as part of our presentation. Incidentally, Franklin appears in the first scene. Ships of this length (50 m) and longer are easily detected, making one wonder about possibility of using RADARSAT (with Navy vessels) for surveillance around Heard Is as it pertains to illegal fishing of the Patagonian Toothfish.
Woodside Petroleum kindly provided us with current meter data from the North Rankin platform from the time that we have a scene showing a rich field of internal waves. We used these as part of our paper. Other topics included the effects of seamounts on the flow of the East Australian Current and the effects of the ~6 knot current (tides plus throughflow) on the sea surface of Lombok Strait, Indonesia.
The papers from the symposium will be published on a CD.
The abstracts for the symposium are on:
http://radarsat.space.gc.ca/ENG/ADRO/Symposium/Abstracts/abstracts.htm
Our paper can be found on: www.marine.csiro.au/~cresswel/radarsat_paper
Our RADARSAT scenes are on: www.marine.csiro.au/~cresswel/RADARSAT/index.html
A description of the satellite is on: http://radarsat.space.gc.ca/ENG/RADARSAT/description.html
On behalf of Paul Tildesley and myself, I gratefully acknowledge travel support from the Earth Observing Centre of CSIRO and CSIRO Marine Research.