Monthly averaged sea surface temperatures (SSTs) are used to drive the model we make the seasonal forecast. There are two ways to generate SSTs to be used by the model and we do both. This page is the index page for the results of our two seasonal forecasts. The first forecast uses persisted sea surface temperatures and the second forecast uses forecast sea surface temeratures.
Persisted sea surface temperatures are generated by modifying the long term monthly average SST field by the latest observed month SST. For example, a forecast in August, September and November is made in July. However, the earliest observed SST available would be for June. We generate the SST fields for the months of July, August, September and November by modifying each month's long term 40 year average by the latest observed SST field, in this example, June. The model is then given these fields and the forecast is produced.
Forecast sea surface temperatures are generated by running an ocean model 6 months into the future to produce monthly SST fields. These SST fields for are then used in the seasonal forecast. Currently, we use the forecast SSTs provided by the CSIR (South Africa).
|South African region||Global region|
|Rainfall - SA||Rainfall - Global|
|Sea level pressure - SA||Sea level pressure - Global|
|Temperature - SA||Temperature - Global|
|Wind vectors - SA||Wind vectors - Global|
|V-wind - SA||V-wind - Global|
|U-wind - SA||U-wind - Global|