To successfully address the challenge of drought, researchers and agriculturists must first understand this complex phenomenon. That’s where agroclimatologists can help. The following are the answers to six frequently asked questions about drought to better understand the work being done by ICARDA to improve nutrition and income of the people who live in drought-prone areas.

Is drought unusual?

Drought is persistent below-normal precipitation. Wherever precipitation varies significantly from year to year, droughts are to be expected. For this reason, drought is not confined to low-rainfall areas. Higher rainfall areas can experience drought, and, in terms of absolute fluctuations, often more than low-rainfall areas (Figure 1). Droughts do vary, however, in severity, area affected, and impact. The West Asia and North Africa (WANA) region, which is 57% hyper-arid and 21% arid (Figure 2), is particularly vulnerable to drought.

Figure 1. Precipitation fluctuations 1951-1985 for three stations under different moisture regimes.

Figure 2. Aridity regimes in the WANA region.

The impact of drought depends on its extent and severity, and a society’s capacity to respond. The direct effects are reduced agricultural productivity due to declines in planted area and yield, and poverty for farmers and livestock owners. Rainfed crops are especially affected (Figure 3) by large production fluctuations, but irrigated crops also can suffer during severe droughts when reservoirs are unable to provide sufficient water. Indirect effects include added pressure on urban resources by migration of rural people, and accelerated

desertification of marginal lands. For governments it can create balance payment problems, either due to declining agricultural export earnings or the need for additional imports.
     The patterns of drought in WANA are extremely variable in their spatial and temporal dimensions. Some droughts are severe enough to affect the entire region, from Morocco to Iran and well beyond, into Afghanistan and Tajikistan. Yet, droughts can also be very local in scale. Syria’s drought of 1999 led to a severe decline in the productivity of rangeland and barley area on the steppe margins. This continued for several years. The drought, however, had relatively little effect on the production of wheat and tree crops in the higher rainfall areas, which recovered from 2000 onwards.

Are droughts predictable?

Droughts cannot be predicted, but only forecast. Forecasts are statements about possible outcomes based on probabilities. For example, a seasonal rainfall forecast is essentially an estimate of the probability that rainfall will be above or below average or about average. In many parts of the world, the El Niño Southern Oscillation (ENSO), a global ocean-atmosphere-coupled weather pattern, is used as an indicator of rainfall patterns for the coming crop growing season. While it is certainly useful to have some indication of possible future weather in one place based on current weather in another, there are difficulties in translating forecasts derived from ENSO into specific management recommendations for farmers. Another problem, given the very large scale of the potential impact area of ENSO, lies in predicting what areas will be affected and fine-tuning forecasts to match the complexity of farming systems, particularly in developing countries. Yet, no clear relationships between drought in WANA and ENSO events have been established, and, in fact, rainfall patterns in the region are controlled by other global weather oscillations, such as the North Atlantic Oscillation (NAO), unfortunately without predictive potential.

Will climate change make droughts worse?

The short answer is ‘yes.’ On the basis of Global Circulation Model (GCM) simulations, the Intergovernmental Panel on Climate Change (IPCC) projects for the region small increases in precipitation, but these increases are likely to be countered by increased temperature and evaporation, and drought is likely to increase.
     The long answer is more ambiguous. First, the scale at which GCMs operate is too large to capture the effects of local topography on weather systems. Second, much depends on the time of the year when the projected changes in temperature and precipitation occur. Increases in temperature and precipitation during the colder part of the year could, for example, enhance growing seasons.

How can societies best respond to drought?

The usual response to drought is crisis management—solving problems as they arise. This approach might seem pragmatic, but during severe droughts it is also very costly in economic and social terms, especially at the level of the individual and community. Ideally, societies in dryland areas should plan for drought within the context of a comprehensive dryland management vision. This means treating drought as a natural but manageable problem in long-term development plans. This requires policies and management plans that integrate the dimensions of agricultural production stabilization and enhancement and environmental sustainability, and a more holistic vision of the contribution of agricultural research.

What drought research is most needed?

Improving the value of drought forecasting for the WANA region should be made a research priority. Drought forecasting is mostly unsuccessful in the region, due to the interaction of meteorological systems from the Atlantic Ocean, Persian Gulf, and Caspian Sea. In the first place, it is necessary to detect the signals that are hidden in the climatic data of the past. This requires collaboration and data sharing among meteorological organizations. Such collaboration remains limited. Research on the potential of using meteorological satellites for identifying, characterizing, and monitoring atmospheric water sources and precipitation events could also help in long-range forecasting.
     Remote sensing for the monitoring and mapping of drought is another potentially important research area. Meteorological and other satellite systems can generate, at global and regional scales, a range of indicators related to vegetation health. These are already used in several early-warning systems to forecast crop condition and estimate agricultural production.

Drought is a natural phenomenon

To combat drought effectively, it must first be recognized and accepted that drought is an entirely natural phenomenon of dryland environments. Once this is understood, it becomes clear that the most effective buffering against drought is through application of proven dryland management principles. This would translate, for example, into not growing crops in marginal environments, in reducing water consumption, in grazing rangelands according to their carrying capacity. The role of the agroclimatologist in this wider context of drought planning is modest, but certainly important. There is much scope for improved climate forecasts in the region, which could lead to timely advice to farmers on how to plan for the coming growing season. There is also great need to monitor drought as it evolves and help decision-makers target assistance to the most affected or vulnerable areas.

Dr Eddy De-Pauw (E.de-Pauw@cgiar.org) is an Agroclimatologist at ICARDA.