Djibouti – FutureWater

Yemen and Djibouti depend on two short rainfall seasons. The summer monsoon from June to September carries most of the rain that feeds rainfed farming and spate irrigation, while October to February brings shorter and more erratic storms that can turn wadis into flash floods. El Niño, the warm phase of the El Niño Southern Oscillation, tends to weaken the first season and intensify the second, so a single event can bring drought and flooding in sequence.

The World Bank needs to know whether the current signal points to elevated drought and flash flood risk in the coming season, early enough for anticipatory action to be discussed with government and development partners. FutureWater delivers the assessment as part of a joint venture led by Acacia Water, producing a rapid seasonal outlook report for each country within six weeks.

The outlook is built in three steps. Historical El Niño events are reviewed against satellite rainfall, vegetation condition, disaster records and humanitarian reporting, to establish which seasons and regions have been most sensitive. A Random Forest model then relates large scale drivers, including the Niño 3.4 index, the Indian Ocean Dipole and antecedent rainfall, to local rainfall and drought anomalies, validated by leave one year out cross validation and reported together with its skill. Forecasts are produced for three climatic zones rather than governorates, because seasonal anomalies follow climate rather than administrative boundaries.

Model output and historical analogues are blended into impact categories anchored in the observed local distribution, so the outlook stays usable where forecast skill is limited. Each country report sets out the seasonal outlook and its implications for anticipatory action, with appendices on drought vegetation response and on El Niño associated flash floods, and a short slide deck for discussion with the World Bank and its partners.

The Middle East and North Africa (MENA) region is considered the most water-scarce region of the world. Disputes over water lead to tension within communities, and unreliable water services are prompting people to migrate in search of better opportunities. Water investments absorb large amounts of public funds, which could often be used more efficiently elsewhere. As the region’s population continues to grow, per capita water availability is set to fall by 50 percent by 2050, and, if climate change affects weather and precipitation patterns as predicted, the MENA region may see more frequent and severe droughts and floods

Map of yearly average precipitation in the MENA region (mm).

The need for alternative and improved water management options is therefore urgently needed, but a clear overview on what the main focus should be is lacking. A broad range of options exists which can be grouped by different approaches such as reducing the demand, increasing the supply, transfer between different sectors, transfer within different sectors, increase storage etc. An important aspect for the MENA region includes desalination.

To explore different options the World Bank initiated an initiative to generate an improved understanding of water issues in the region and overview of available options under different scenarios of water supply and demand management with special focus on desalination, taking into account the energy nexus and environmental concerns. As part of this initiative, FutureWater will carry out an assessment of water stress in the MENA region, including associated marginal cost of water supply to meet the water supply need. Conducting consultation workshops and meetings will be organized with relevant parties in the region (governmental, universities, civil society groups).