Ethiopia is facing a fourth consecutive growing season drought which threatens grain supplies for 1999/2000 and 2000/01. Ethiopia's corn production has faced several shortages during the last two decades (Figure 1), but overall crop production has grown. Increased area planted and stronger yields resulted in record production in 1996.
Figure 1. USDA Corn Production and Area Planted Estimates
In February 2000, USAID's Office of Foreign Disaster Assistance (OFDA) confirmed appeals by the Ethiopian government's Disaster Prevention and Preparedness Committee (DPPC) for emergency food assistance in excess of 898,936 metric tons (MT) (Figure 2), or an increase of over 200,000 MT from the drought year of 1999.
Figure 2. Food Aid Requirements (from DPPC)
The current monthly projections of food aid by DPPC and OFDA (Figure 2), assume that the "belg" rainy season from March-July will quickly relieve acute food insecurity in the southeastern pastoral areas and belg cropping areas. The belg season accounts for around 8 to 10 percent of annual grain production, but in some areas it is the main harvest (Figure 3). However, if the "belg" rains from March-May fail, another an extra several hundred thousand MT of food are expected above this original estimate.
Figure 3. Belg-Rain Production Areas (from FEWS)
The onset the belg season rains has already been delayed by over a month which is an indicator that this year's belg growing season will be shorter than normal and will reduce yields (Figure 4).
Figure 4. Delay in March 2000 Rains Caused by Delay in ITCZ Migration (from FEWS).
If the belg rains indeed fail, the projected food aid needs in July will increase. But transporting food supplies during the July is nearly impossible as the July "meher" rains annually flood roads and make travel impassable in rural areas. Another poor belg season would also adversely affect national food supply prospects for 2000/01, since these rains are also crucial for the preparation and planting of "meher" (main season) crops.
DROUGHT SPARKS FIRES IN SOUTHERN ETHIOPIA
The two-year drought created conditions that allowed fires in southern Ethiopia to flare out of control from mid-February thru March, 2000. Due to the extended dry season, widespread outbreaks of forest fires have been reported in southern Ethiopia. The Global Fire Monitoring Center (GFMC) estimated from aerial surveys that 10 to 15% of the total park area in the Nechi Sar National Park was burned, and more than 247,000 acres (100,000 hectares) of forests burned within SNNPR, Oromiya, and Somali Regions. Dry conditions spark fires which are thought to have been started by pastoralists residing close or inside the parks in order to encourage growth of fresh grass and to eliminate tick populations; farmers clearing forest for cultivation; and honey collectors smoking out bees in areas dried out by drought.
La Niña Drought and Delay in Intertropical Convergence Zone (ITCZ)
Ironically, Ethiopia's drought may be associated with the same weather event, La Niña, thought to be the source of cyclones and floods in Mozambique. The Mozambique storms intensified the drought in the Horn of Africa as moisture was dragged southwards and delayed the Intertropical Convergence Zone's (ITCZ) migration northward. With topical movement still active off the South-African coast, the ITCZ has not yet established itself in Ethiopia for the belg rain season.
La Niña is the cold counterpart of El Niño, or the other extreme of the El Niño/Southern Oscillation (ENSO) cycle where sea surface temperatures in the tropical Pacific drop below normal (Figure 5).
Figure 5. El Niño and La Niña Sea Surface Temperatures in the Pacific Ocean (from NOAA)
Both El Niño and La Niña impact global weather patterns by teleconnections (Figure 6). In many locations, especially in the tropics, La Niña (or cold episodes) produces the opposite climate variations from El Niño. For instance, parts of East Africa receive wetter than normal rainfall during El Niño years, but are prone to droughts during the cold La Niña phase.
Figure 6. La Niña Global Teleconnections (from NOAA)
La Niña sometimes occur after some El Niño years, but not all years. The duration of the current La Niña event is 1.5 years (Table 1), corresponding to the length of the drought in Ethiopia.
Table 1. Recent El Niño and La Niña Events (from NOAA)
(weak periods designated as C- or W-, moderate strength periods as C or W, and strong periods as W+ or C+).
For East Africa, La Niña teleconnections also blend with the sea surface temperatures in the Indian Ocean, which may alter the magnitude of ENSO events. The Indian Ocean has been warmer than usual in the past, which meteorologists say helped bring large cyclones and rain to Mozambique and delayed the ITCZ from migrating northward.
Precipitation Forecast for March-May, 2000
The Nairobi-based Drought Monitoring Center (DMC) held a Climate Outlook Forum in Arusha, Tanzania in February 2000. They reviewed the state of the global climate system and its implications for the Horn of Africa. Among the principal factors taken into account were the decaying La Niña episode, and near-average, and slowly cooling, sea-surface temperatures over much of the tropical Indian Ocean.
The Climate Outlook Forum for the Horn of Africa examined the evolution of the La Niña episode that started in 1998 and sea surface temperature anomalies over the Indian and Atlantic oceans together with other factors that affect the climate of the sub-region. These were assessed using coupled ocean-atmosphere models, physically based statistical models and expert interpretation. The current status of seasonal-to-interannual forecasting allows prediction of spatial and temporal averages, and may not fully account for all factors that influence regional and national climate variability.
The final forecast by the Climate Outlook Forum is shown Figure 7, where below normal rains are expected for the March - May season in the eastern parts of the Horn, including most of Somalia, eastern Kenya, and southeastern Ethiopia. With the delay of the ITCZ and a possible belg season failure, this will decrease soil moisture levels in important main-season agricultural areas and could significantly downgrade the potential yield of the main-season meher harvest. This medium-range weather forecast and the delay of ITCZ indicate that emergency food relief requirements will probably escalate from the original estimates for June of this year.
Figure 7. Climate Outlook for March-May, 2000 (from DMC)).
For more information, contact Curt Reynolds with the Production Estimates and Crop Assessment Division on (202) 690-0134 or by e-mail at ReynoldsC@fas.usda.gov.