NASA shows severe drought

A prolonged dry spell in southern Africa in early 2024 scorched crops and threatened food security for millions of people.

The drought has been fuelled in large part by the ongoing El Niño, which shifted rainfall patterns during the growing season.

From late January through mid-March, parts of Southern Africa received half or less of their typical rainfall, according to researchers at the Climate Hazards Centre (CHC) at the University of California, Santa Barbara. February was especially dry.

Precipitation would normally be highest from December through February. But CHC researchers analysing the Climate Hazards Centre InfraRed Precipitation with Station data (CHIRPS) found that February 2024 was the driest February in the 40-year data record for an area spanning much of Zambia, Zimbabwe, southeastern Angola and northern Botswana.

The parched conditions came at a critical time when crops need ample water supply for growth and to produce grain. Insufficient rain and high temperatures resulted in crop failure in several countries. By the end of February, maize crops had withered and died on one million hectares in central and southern Zambia - almost half of the country’s maize-growing area.

Livestock

The dry spell also affected livestock. Over 9 000 drought-related cattle deaths were reported in Zimbabwe, and over 1.4 million cattle are considered at high risk of drought conditions and death due to a lack of pasture and water.

Researchers at the Famine Early Warning Systems Network (FEWS NET) have been tracking rainfall and crop conditions in southern Africa throughout the growing season, which runs from about November to April. FEWS NET is a programme supported by the United States Agency for International Development (USAID) in partnership with other agencies, including the United States of America's National Aeronautics and Space Administration (NASA).

The map shows soil moisture conditions at the root zone - an estimate of how much water is available for crops - in southern Africa for March. Orange and red areas depict deficits in soil moisture. Data for the map come from the FEWS NET land data assimilation system, which uses observational datasets and seasonal climate forecasts to provide monthly forecasts of hydrological conditions relevant to food security in Africa and the Middle East.

Maize

Maize is the single most important cereal crop in southern Africa, accounting for a majority of the region’s cereal production and 21% of the average person’s diet. Its success or failure can affect the amount of food available. FEWS NET experts estimated in March that millions of people faced 'crisis level' food insecurity in Zimbabwe, Malawi, central Mozambique and Madagascar. This level means that households are not able to meet their minimum food needs without seeking humanitarian food assistance or taking drastic measures such as selling essential assets.

Before the 2024 growing season, FEWS NET scientists had identified southern Africa as a region of concern. An October 2023 report cited past research showing that during years with a moderate to strong El Niño, the region has often seen below-normal rainfall and above-average daytime temperatures during key months of the growing season, reducing yields of maize.

“Based on our modelling and previous research on El Niño and crop yields, we were able to issue advanced warning of this drought back in the fall of 2023,” Amy McNally, a FEWS NET researcher based at NASA’s Goddard Space Flight Centre, said.

Scientists with FEWS NET and the GEOGLAM Crop Monitor for Early Warning shared the 2024 growing season forecast with humanitarian aid organisations, bringing attention to the potential drought, reduced crop harvests and exacerbation of already-inflated maize prices.

“This allowed USAID’s bureau of humanitarian assistance to aim to have emergency food assistance resources allocated ahead of time,” McNally said.

Water shortages

Falling crop harvests and water shortages led to Zambia, Malawi and Zimbabwe declaring national disasters. Water for drinking and cooking has become scarcer as the region deals with an ongoing cholera outbreak.

The United Nations (UN) office for the coordination of humanitarian affairs has forecast dry conditions and below-normal rainfall until June for much of southern Africa. Many farmers in the region are either in or approaching the time of crop harvest, so the full impacts of the failed season are yet to be felt.

Although there may be no relief on the horizon for crop production in the near term, next year may have more favorable conditions. The April El Niño-Southern Oscillation (ENSO) forecast indicates that there is an 85% likelihood of a La Niña developing in late 2024 and early 2025, which is often associated with above-normal precipitation and normal or above-normal maize yields in southern Africa.