The East African paradox

Meanwhile over Kenya and Tanzania, the long rains from March to May start later and end sooner - leading to an overall decrease in rainfall.

This observed change sits uncomfortably next to predictions of a wetter future in the same season - a problem scientists have termed the East African Climate Paradox.

Central Africa, one of three regions on the planet where thunderstorms drive the rest of the planet's tropical and sub-tropical weather systems, lives perilously close to the rainfall minimum needed to support the world's second largest rainforest system. Even a little less rainfall in the future could endanger the forest and its massive carbon store.

Africa's complex climate system is, unusually, influenced by the three main global ocean basins.

Emerging from one of those rapidly warming oceans, tropical cyclones Idai and Kenneth in March and April 2019 destroyed parts of Mozambique, Zimbabwe and Malawi, with Kenneth following a particularly unusual path over Tanzania.