By JEFF OTIENO
What is normal rainfall?
•Above average rainfall, normal rainfall and below average rainfall are calculated using the long-term average rainfall of a particular ecological zone. The long-term average rainfall of a region is the mean rainfall amount for the past 30 years. It is calculated for both the long rains and short rains.
•Currently, the agreed 30-year period that meteorologists use to calculate long-term averages for various ecological zones is between 1980 and 2010. The period is normally set by the World Meteorological Organisation.
What amounts to normal rain for a particular ecological region?
•An ecological region is expected to receive normal rainfall when the predicted amount is within the range of 75 per cent and 125 per cent of the long-term average. •When the rainfall received is 125 per cent above the long term average of that particular region, it is above normal. •Below normal rainfall is when an ecological zone receives below 75 per cent of the long-term average.
A large part of East Africa is expected to receive normal to below normal rainfall in the current long rains season.
According to the forecast produced by the IGAD Climate Prediction and Applications Centre (ICPAC), there is an increased likelihood of near normal to below normal rainfall over the central parts of Sudan, central Eritrea, eastern Djibouti, south-western and north-eastern Rwanda, south-eastern Burundi, north-eastern Uganda and south-eastern parts of South Sudan.
Large parts of Ethiopia, Somalia, Tanzania and Kenya are also expected to receive normal to below normal rainfall.
“There is a 40 per cent probability of near normal rainfall, a 35 per cent probability of below normal rainfall and a 25 per cent chance of above normal rainfall,” said ICPAC, which produces regular rainfall forecasts for the region.
The rainfall is expected to minimise the devastating effects of drought in the region — mainly in the arid and semi-arid areas — which has killed thousands of heads of livestock and left millions of people in East Africa in need of emergency food supplies.
According to the World Food Programme, as at February this year, 7.8 million people were in the crisis or emergency phase, with the largest numbers being in Ethiopia (2.9 million), South Sudan (2.5 million), Kenya (1.5 million), Somalia (731,000) and Uganda (180,000).
The long rains season is considered the backbone of the region’s rain-fed agriculture, as it contributes the biggest percentage of rainfall in the region.
Indeed, the region’s food security status normally depends on the performance of the long rains, especially for the production of maize, wheat, rice and beans.
But meteorologists warn that if below normal rainfall is realised in the cited areas, the food situation may worsen before the end of the year.
In its latest update on global food security, WFP said if below normal rainfall were realised in the greater part of Kenya, Somalia and most areas of Ethiopia, Djibouti and central Tanzania, there would be a depletion of pasture and water resources, affecting the food and nutrition security situation in the region.
“Northeast, eastern and southern Kenya and southern Somalia have persistently suffered drier-than-average conditions since the early stages of the short rains season,” said WFP.
The Food and Agriculture Organisation cited Kenya and Uganda as the countries in the region facing localised food insecurity — mainly in the arid and semi-arid areas — due to reasons ranging from the vagaries of weather to a large influx of refugees from the war-torn countries of South Sudan and Somalia.
In South Sudan, the main drivers of food insecurity in the are conflict-related displacement, disruptions to livestock and crop production and high staple food prices.
The conflict has led to the internal displacement of 1.4 million South Sudanese, mostly in the states of Jonglei, Unity and Upper Nile, where the conflict has been largely concentrated.
“It has also caused sharp increases in the price of staple foods and reduced stocks. Stocks from own production are expected to be depleted within the first quarter of 2015 in the worst-affected counties,” WFP said.
In Kenya, poor rainfall is to blame for the more than 1.5 million people facing severe food shortages. The government sounded a drought alarm early in the year, after putting 23 counties under the “alert drought” status. Most of the counties are in the arid and semi-arid regions, where pastoralism is the predominant source of livelihood.
The Kenya government, through the Devolution Ministry, has already set aside Ksh3 billion ($33.3 million) to tackle drought in the country.
In Uganda, 180,000 people are facing severe food shortages in Karamoja region, which has suffered two years of below-average crop production.
Among the principal factors ICPAC took into account while coming up with the regional forecast were the observed and predicted atmospheric ocean conditions, mainly in the Indian and Atlantic Oceans, in relation to moisture transportation and rainfall distribution.
“The dominant climate forcing processes included the continued cooling and warming over the western Indian Ocean as well as south-eastern Atlantic Ocean and eastern Indian Ocean respectively with implications on the March-May 2015 forecast period,” ICPAC said.