Source: ‘2017/18 season difficult to predict’ | The Financial Gazette November 9, 2017
By Farai Mabeza
SOUTHERN Africa is headed for a rainy season that is difficult to predict, the Famine Early Warning Systems Network (FEWSNET) has said.
In September, the Southern Africa Regional Climate Outlook Forum announced that normal to below-normal rainfall is expected across most of Southern Africa between October and December 2017, while normal to above-normal rainfall is expected for January-March 2018.
In its report for October FEWSNET, however, said the latest Climate Prediction Centre/International Research Institute for Climate and Society outlook for October indicates that during the main rainy season (October 2017-March 2018) the La Niña ENSO phase is most likely to occur, instead of the neutral ENSO phase that was initially projected to continue.
ENSO or El Niño-Southern Oscillation is an irregularly periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting much of the tropics and subtropics.
The warming phase is known as El Niño and the cooling phase as La Niña.
The La Niña phenomenon, the opposite of El Niño, normally results in wetter-than-normal conditions in the southern Africa region from December to February.
“Because the climate drivers that normally provide an indication of how the season may turn out are close to neutral, this season is difficult to forecast and international and national forecast models will need to be monitored closely in the coming months,” FEWSNET said.
On Zimbabwe, FEWSNET gave a seasonal rainfall forecast based on a recent analysis of international forecast models by American scientific agencies, the National Oceanic and Atmospheric Administration and United States Geological Survey.
It said the start of the 2017/2018 rainy season is likely to be normal and total cumulative seasonal rainfall during the October/November 2017-March 2018 period is likely to be average tending to below average.
In the northern and other typically higher rainfall areas of Zimbabwe, this forecast means there is likely to be normal crop establishment and growth, especially following an above average 2016/2017 rainfall season that resulted in improved soil-moisture conditions in some areas.
For the southern, western, extreme northern areas that are arid and drought-prone, this forecast could mean erratic rainfall early in the cropping season, resulting in reduced cropped area.
These areas normally experience mid-season dry spells, so this could affect crops during the critical vegetative and reproduction stages.
The green harvest that is expected in February and the main harvest in April maybe late in these drier areas.
On food security, FEWSNET said several markets in the region remained well supplied due to the impact of the above-average harvests this year.
These stable food supplies and low demand have resulted in prices for maize grain either remaining stable or declining in comparison to both last year and the five-year average.
In some parts of Zimbabwe, prices remain 31 and 24 percent below last year and five-year average, respectively.
Similar trends have been reported in Malawi where the current national price is 54 and 15 percent lower than last year and the five-year average.
In Mozambique, food prices were also reportedly stable and lower than the five-year average.