Five rainy seasons without rain

In this part of Africa a year's rain comes in two short bursts. When one fails, families sell animals and wait for the next; when two fail they move. After five, the land had nothing left: pastures and water holes dried up, millions of goats, cattle and camels died, and many families left their homes in search of water and food.N1

A long La Niña in the Pacific, with a cool western Indian Ocean, kept the short rains away three years running. But the heat mattered too: higher temperatures dried the soil and the plants faster. World Weather Attribution found that the drought, measured by both rain and evaporation, had become about 100 times more likely with human-caused warming, mostly through the heat rather than through less rain.S1

Wajir's normal year has two peaks of rain, in April and November, and almost nothing in between. On the Lab's seasonal maps for September to November, the short-rains season, the dry hole over north-eastern Kenya and southern Somalia deepens from 2021 to 2022, while the Ethiopian highlands, which have different seasons, stay wet.

Soil moisture adds up the seasons: by November 2022, the month that should have been the wettest of the year, the top layer of soil over most of Somalia and north-eastern Kenya was as dry as the desert to the north.

The long rains of 2023 were near normal. Then in late 2023 an El Niño and a strong positive Indian Ocean Dipole, warm water off East Africa, brought the opposite extreme: September to November gave Wajir more than twice its normal rain, and rivers in Somalia and Kenya burst their banks over land too dry and bare to soak it up.