Radar Equipment To Be Installed At Skukuza
By Melissa Wray
In Kruger National Park
Skukuza has been identified by the South African Weather Service as one of three priority locations in the country for a sophisticated radar apparatus that will help the weather service determine if bad weather is heading for the lowveld. Sometime this winter, depending on when the environmental impact assessment for the radar station is completed, a crew will arrive to install radar equipment and high-tech communications infrastructure for the weather service.
Once installed, the radar station will fill a gap in the weather service's network of radar equipment. Existing radar stations are found in Cape Town, Port Elizabeth, East London, Umtata, Durban, De Aar, Bloemfontein, Bethlehem, Ermelo, Pretoria and Polokwane. As well as Skukuza, the two priority areas for new stations are in the north west of South Africa near Botswana and in the northern part of KwaZulu-Natal.
The weather service's Nico Kroese says that the new radar equipment will not be used to formulate the daily weather forecasts that you hear on the radio, but will be able to give warnings about two hours in advance of heavy rainstorms and hailstorms.
If a potential hailstorm is detected, the weather service will alert the media in the relevant area as well as the airlines. Because of its closeness to Mozambique, the radar will also be able to monitor the progress of tropical cyclones, such as caused the 2000 floods, as they are approaching South Africa.
The radar equipment can monitor clouds occurring within a radius of approximately 200km. The equipment sends out a microwave signal, which has a wavelength of three to 10cm. If this focussed pulse of energy hits a hailstone or a drop of rain, it is scattered and reflected back towards the earth, where the radar station can receive the faint remnants of the signal. Various calculations of direction and strength of the pulse can then be performed, and approaching storms identified.
The information gathered by the radar station is transmitted by a broadband telecommunications link to the necessary department of the weather service for analysis. The radar equipment that will be installed at Skukuza is a second-hand system from the United States that has been totally revamped.
It is currently sitting in Irene, Pretoria, waiting for the environmental impact process to be completed before being installed. As well as the radar ball itself, a small room is needed to house the associated computer equipment.
The weather service is contemplating making the installation in an old shipping container to minimise the impact that constructing a new building would have. Initially three sites were identified in Skukuza as possible locations for the equipment, but two more have been added during the environmental impact process.
The potential sites are two sites near the airport, at the water reservoirs near the game capture boma, at the water reservoir near the staff soccerfield, and along the road to the abattoir. The two new sites were added because the original sites were not ideal either visually or from a radar point of view. In order to test the new sites, the consultants raised a blimp to the appropriate height and then drove around the area checking to see if they were visible to tourists.