DROUGHT INDICES BEING USED FOR THE GREATER HORN OF AFRICA (GHA) Christopher Oludhe IGAD Climate Prediction and Applications Centre (ICPAC) Inter-Regional Workshop on Indices and Early Warning Systems for Drought Lincoln, Nebraska, USA, 8 11 December 2009
Introduction The IGAD Climate Prediction and Applications Centre (ICPAC), formerly known as the Drought Monitoring Centre, Nairobi (DMCN), is a specialized regional centre of the Inter- Governmental Authority on Development (IGAD) charged with the responsibility of climate monitoring, prediction, early warning and applications for the reduction of climate related risks including those associated with climate variability and change. ICPAC serves 10 countries within the GHA
ICPAC PARTICIPATING COUNTRIES 30 20 Sudan Eritrea Djibouti 10 Ethiopia 0 Somalia Rwanda -10 Uganda -20-30 Burundi Kenya Tanzania -10 0 10 20 30 40 50
Nairobi ICPAC
Mission To contribute to climate monitoring and provide timely climate information and prediction services for early warning and mitigation of the adverse impacts of extreme climate events on various socio-economic sectors in the region. The early warning products enable users to put mechanisms in place for coping with extreme climate and weather related risks for sustainable development in the Greater Horn of Africa (GHA).
Operational Activities Development and archiving of regional and national quality controlled climate databanks Data processing including development of basic climatological statistics Timely acquisition of near realtime climate and remotely sensed data Monitoring space-time evolutions of weather and climate extremes over the region Generation of climate prediction and early warning products Delineation of risk zones of the extreme climate related events Enhanced networking with the NMHSs, regional and international centers for data and information exchange Timely dissemination of early warning products Conduct capacity building activities in the generation and application of climate products Organization of Climate Outlook Forums (COFs) for the GHA countries Enhancement of interactions with users through users workshops and pilot application projects Climate change monitoring, detection and attribution including climate change modeling.
ICPAC s Products DEKADAL PRODUCTS RAINFALL DISTRIBUTION DROUGHT SEVERITY AGROMETEOROLOGICAL CONDITIONS GENERAL IMPACTS WEATHER OUTLOOK CUMULATIVE TIME SERIES GRAPHS MONTHLY AND SEASONAL PRODUCTS CLIMATOLOGICAL SUMMARIES DROUGHT SEVERITY AGROMETEOROLOGICAL CONDITIONS DORMINANT SYNOPTIC SYSTEMS CLIMATE OUTLOOK. GENERAL IMPACTS PRE - SEASON CONSENSUS OUTLOOKS CUMULATIVE GRAPHS CLIMATE WATCH Provides an update regarding the current and projected state of extreme climate events and their potential impacts
Drought Monitoring at ICPAC Drought is a normal part of climate and occurs in virtually all regions of the world. Droughts differ in three essential characteristics: intensity, duration, and spatial coverage. A critical component of planning for drought is the provision of timely and reliable climate information, including seasonal forecasts, that aids decision makers at all levels in making critical management decisions. These may include among others Onset/Timing, Intensity, Cessation, Duration as well as the Spatial extent of drought.
Types of Droughts
Drought Severity Index Used at ICPAC The drought severity at ICPAC is derived from indices which consider all observations which are less than first quartile of ranked historical records to be dry while those which are more than third quartile are considered wet. Dry Near Normal Wet Min Q1 Q3 Max
Dekadal Drought Severity Index 20 15 10 LATITUDE ( N/S) 5 0 Wettest on record -5 Wet Near normal Dry -10 25 30 35 40 45 50 LONGITUDE ( E) Drought Severity Index for Dekad 24 (21-31 August) 2003 Drought Severity Index for Dekad 26 (11-20 September) 2005
Seasonal Drought Severity Index Drought severity index for March 2009 Drought severity index for October 2009
Seasonal Rainfall Anomalies Rainfall Anomalies for January -March 2009 Rainfall Anomalies for August October 2009
Advantages Simple technique that only requires ranking historical data from a given station. Requires only a single parameter (Rainfall) to be examined. Disadvantages Tends to be highly skewed with fewer historical data Stations with different data lengths cannot be compared Fewer categorization of drought Does not take into account other climate parameters
Use of Rainfall Cumulative Graphs
Northern Tanzania NOTHERN TANZANIA 600 2005 LTM 1984 2000 2004 1996 500 Cummulative Rainfall 400 300 200 100 0 jan feb mar apr may jun jul aug sep oct nov dec Months
EXAMPLES OF DROUGHT IMPACTS LOSS OF LIVESTOCK AND PASTORAL LIVELIHOODS
SHORTAGE OF SAFE DRINKING WATER
Impacts of Drought Urban water Supply Hydropower Generation Food Security Livelihood of pastoralists
CONCLUSIONS A critical element of drought planning and mitigation is the early detection of emerging drought. This requires continuous monitoring of climate and water supply conditions. An important element of drought early warning systems is the timely and effective dissemination of the information to decision makers. ICPAC plays an important role in providing the IGAD sub-region with weather and climate advisories and more importantly, timely early warnings on extreme climate events including floods and droughts.
END THANK YOU Website: www.icpac.net E-mail: logallo@icpac.net