Climate change and Desert Locust Swarms
Photo credit: Al Jazeera

Climate change and Desert Locust Swarms

There is increasing evidence of a correlation between climate change and desert locust swarms. The recent outbreak of desert locusts across eastern Africa is causing devastating losses to agricultural production and will exacerbate malnutrition and hunger in the region. The locusts thrive during periods of heavy rainfall in habitats that are normally arid in Africa. Experts say that one key factor in the recent swarms of locusts is the unusually wet weather over the past 18 months in the region (National Geographic). The Indian Ocean Dipole has been linked to the increased number of storms.

locust swarm extent


Source: National Geographic

According to the FAO, 13 million people in Djibouti, Eritrea, Ethiopia, Kenya, and Somalia are already food insecure and the arrival of the desert locust will make this population more vulnerable to famine and put another 20 million people at risk (FAO).

“There is a link between climate change and the unprecedented locust crisis plaguing Ethiopia and East Africa. Warmer seas mean more cyclones generating the perfect breeding ground for locusts. Today the swarms are as big as major cities and it is getting worse by the day.”
Antonio Guterres
UN Secretary General

This outbreak was made worse when the region received much heavier rains from October through December (Bloomberg). aWhere’s weather data confirm the patterns of heavier than normal rainfall throughout the region from October to December 2019. The three maps below of October, November, and December 2019 show the difference in precipitation from the long-term normal – aWhere’s long-term normal is calculated from 2006-2018. The areas that are brighter blue indicate heavier rainfall than the normal. The upcoming rainy season from March-May could worsen the swarms if there is higher than expected rainfall.

East Africa weather

With aWhere’s historical data, the severity of future desert locust swarms could be anticipated. While countries are taking measures to mitigate the impacts by providing targeted applications of pesticides, variable weather may bring larger swarms in the future as heavier and more frequent rainfall events allow the desert locust to flourish. aWhere’s weather data can generate insights to support planning to manage pest outbreaks or plan infrastructure in Africa to deliver economic resilience to climate change.