Trend analysis of rainfall and the length of the growing season of Central Sudan

Abstract EN

In this study rainfall trends were studied using Mann- Kendall test in the central Sudan.

Also, the impacts of such trends on the onset, end and the length of the growing season were investigated.

Nineteen stations were selected to represent the central Sudan.

The seasonal rainfalls show high variability ranging between 0.21 and 0.42.

In 95% of the stations, the seasonal rainfall experiences decreasing trends, since the end of the period 1970s.

In 62% of these the decreasing trend is statistically significant (P < 0.05 and P < 0.01).

The statistically significant decreasing magnitude in the seasonal rainfall is ranged between 86 and 11% by the Theil and Sens's method.

The monthly rainfalls shows mixed decreasing and increasing trends.

With the exception of Elobied station, the length of the growing season experiences a decreasing trend, which is statistically significant only for Damazine, Nyala, El Renk and Sennar stations.

The average magnitude of reduction in the length of the growing season is found to be 30%.

The onsets and ends of the growing season were disrupted using the Cocheme and Franquin approach.

The onset is very important since it is used as a drought adaptation technique by local farmers.

It can be concluded that there is a variability and change in rainfall and length of growing season.