The Impact of Cold Events on Ethiopia
Tsegay Wolde-GeorgisEmbassy of Ethiopia
Washington D.C. USA
tsegay@tidalwave.net
One of the goals of the current Ethiopian government is food self sufficiency. It provides inputs such as fertilizer and seeds and extension services to farmers, who are also encouraged to participate in water and soil conservation activities. These policies have already produced impressive results in food output, such as the record harvest of 1996/97 which brought food security at the national level for the first time in years. Adequate and credible dissemination of weather information to farmers by government can strengthen the positive effects of the above agricultural policies on food security.
Various Ethiopian governments have tried to use climate information for food security. However, climatic planning in Ethiopia depended on averages of rainfall and temperature information from the limited number of meteorological stations. However, conclusions based on these temperature and rainfall averages from the various stations can be deceiving. The stations are limited in number (less than 130 in 1997) and Ethiopia has diverse microclimates (NMSA, 1989). Agricultural drought could occur due to fluctuation in rainfall temporally and spatially. The effectiveness of rainfall, however, depends on the length of the rainy season, its distribution and intensity. For example, the unusually heavy rainfall in November 1997 in Ethiopia was of little use for food production, because the timing was at the end of the harvest season not suitable for planting. (The month of November is the driest in the Ethiopian meteorological calendar).
In addition to its traditional role of inventorying meteorological information, the Ethiopian National Meteorological Services Agency (NMSA) actively uses global sea surface temperature conditions (such as El Niño) for predicting seasonal rainfall in Ethiopia (Glantz, 1996). This was institutionalized after the mid 1980s following the 1983/84 famine. In the 1987 drought, El Niño and Southern Oscillation (ENSO) was used by NMSA as an early warning for the first time. The early warning was distributed to users such as the Relief and Rehabilitation Commission (RRC) [now, Disaster Prevention and Preparedness Commission or DPPC], the Ministry of Agriculture and donors.
Researchers at NMSA and policy makers in Ethiopia believe that the state of sea surface temperatures (SSTs) in the tropical Pacific Ocean affect Ethiopian climate through teleconnections (Haile, 1988). (NMSA also believes that the Atlantic and the Indian oceans' SST anomalies also affect Ethiopia). Other studies also support the NMSA's conclusions. For example, the variability between high and low flood levels of the Nile River, whose major water source is highland Ethiopia, is related to the ENSO cycle (Quinn, 1992). Ethiopia used El Niño information as an early warning for the 1987, 1992 and 1997 droughts. Based on the information provided by NMSA, the DPPC was able to disseminate an early warning to users.
Recently, Ethiopian policy makers have began to incorporate La Niña information into their early warning system as well. Mr. Teshome of the DPPC's early warning department confirmed that they used La Niña information to prepare for the 1996 summer floods in Ethiopia (Wolde-Georgis, 1997).
Until now, Ethiopian policy makers focused on El Niño, which is believed to be one of the causes of drought in Ethiopia. La Niña is believed to cause heavy rainfall and flooding. Until recently, the focus of policy makers on the phenomenon of cold events was less than that of El Niño. The main cause of disaster in Ethiopia was drought and no one would be ready to take a forecast of heavy rainfall very seriously. Despite this, the DPPC and NMSA began La Niña-based early warning information since 1996.
The following broad relationships are believed to occur between the belg and kremt seasonal rainfalls in Ethiopia and the SST anomalies (SSTA) (NMSA, Bekele, 1997).
- Cold SSTA is strongly associated with deficiency of belg rainfall.
- Cold event is associated with heavy kremt rainfall.
- Warm SSTA is associated with normal and above normal belg rainfall.
- Warm SSTA is associated with widespread meteorological drought.
- SSTA may not be the only cause of drought in Ethiopia.
The relationship between Ethiopian weather conditions and all the cycles of the SSTA in the oceans are not yet conclusive, because of limitations in data and the diversity of Ethiopian microclimates. However, there is an association between Ethiopian droughts and El Niño (Wolde-Georgis, 1997). Being an El Niño year, the 1997 kremt, for example, was unusually dry in Ethiopia. The reservoirs around Addis Ababa were unusually low in 1997 (NMSA, 1997). November is typically the driest month in Ethiopia, but it was unusually wet in 1997. This anomaly may be related to the major El Niño of 1997.
According to the NMSA, cold events cause dificient rainfall in the belg season and heavy rainfall during the kremt season. Reports from Ethiopian media during the 1998 kremt show exceptional floods in many parts of Ethiopia. Many rivers, including the Awash, have flooded their banks, leading to the evacuation of many settlements in the Ethiopian Rift Valley. Thus, the 1996 and 1998 La Niña events were followed by unusually heavy rainfall during Ethiopia kremt rainfall. The early warning report of the DPPC also show that the belg 1998 food production was unusually low (DPPC 1998).
Policy makers need to take advantage of the forecasts of cold events and incorporate them into their policies. Farmers could be encouraged to plant seeds that need heavy rainfall and long maturation periods. Water conservation measures such as dams could harvest the heavy rainfall for future use. Flooding and erosion prevention measures could be taken ahead of the rainy season.
Unique local conditions should be taken into consideration in any policy recommendations so that the early warnings could be effective and believable in the future. Ethiopia is characterized by diverse microclimate zones, because of its tropical mountains. Local differences in microclimates could make the implementations of a credible forecast that covers the whole country difficult. However, the SST information could still be used for national level policies. The national policies could include increasing the food security reserves, export and import policies and foreign aid.
It is important that research and policies focus on the impact on local weather of all cycles of SST conditions. Until now, policy makers and researchers considered El Niño that led to drought as abnormal and all the other parts of the ENSO cycle as normal. The cold events received very little attention to make good use of their presence or to prevent their negative impacts. This attitude is changing with the spread of information and education. Ethiopia is vulnerable to climate variability and needs to follow the SST anomalies and their impact in order to attain their goal of improved food security.
Bibliography
Addis Zemen (Ethiopian Amharic Daily). (Hamle 3, 1990, Ethiopian Calendar). July, 10, 1998. Heavy floods expected in some parts of Ethiopia.Bekele, F. 1997. Ethiopian Use of ENSO Information in Its Seasonal Forecasts, Internet Journal of African Studies. No. 2. March. www.brad.ac.uk/research/ijas/ijasno2/ijasno2.html
Disaster Prevention and Preparedness Commission (DPPC). Early Warning System Report. 1998 Belg Production and Food Prospects. August, 1998.
Glantz, M.H., 1996. Currents of Change. Cambridge: Cambridge University Press.
Haile, Tesfaye. 1988. Causes and Characteristics of Drought in Ethiopia. Ethiopian Journal of Agricultural Sciences. Vol. 10, No. 1-2. Pages 111-20.
NMSA. 1996. Climatic and Agroclimatic Resources of Ethiopia. Meteorological Research Report Serious, Vol. 1, No. 1, January. Addis Ababa, Ethiopia.
NMSA. Early Warning System Report, November 1997. The Impact of Abnormal Weather in 1997.
Quinn, William. 1992. The Study of Southern Oscillation-related Climate activity from AD 622-1900 incorporating Nile River flood data. In Editors Henry F. Diaz and Vera Markgrat. El Niño, Historical and Paleoclimatic Aspects of the Southern Oscillation. Cambridge: Cambridge University Press. Pages 119-49.
Tsegay Wolde-Georgis. 1997. El Niño and Drought Early Warning in Ethiopia. Internet Journal of African Studies, No. 2. March. www.brad.ac.uk/research/ijas/ijasno2/ijasno2.html