HE Data for 21 January 2010
The graphic shows accumulated rainfall based on the hydro-estimator over South Africa, Namibia, and Botswana from 22 December 2009 to 21 January 2010. Rainfall totals over the Mpumalanga and Gauteng Provinces are between 200 mm and 400 mm, while northern Namibia has accumulated values well above 300 mm.
How well do the HE data correlate with the seasonal rainfall data that we examined earlier? Review the data, then answer the question below.
How well do the HE data correlate with the seasonal rainfall data that we examined earlier?
The correct answer is A.
Although the seasonal rainfall is given as a percentage of the normal rainfall over South Africa, the HE products compare well with the seasonal data. For example, over the Ermelo area, seasonal rainfall data have values up to 150% of normal, while the HE indicates that the area received over 300 mm of rainfall between 22 December and 21 January. Although these datasets deal with different values, the trend of heavy rainfall over the Vaal Dam catchment region remains constant throughout. This kind of information should be of concern to meteorologists on duty and keep them on alert.
