Abnormally warm West Pacific sea surface temperatures — in part driven by a weak La Nina, in part driven by global warming — produced changes in atmospheric circulation that considerably reduced rainfall over Eastern and Southern Africa during 2016. As a result, places like Rwanda, Kenya, Eithiopia, South Sudan, and Somalia experienced some of their worst droughts in decades.
(According to the Famine Early Warning Network, more than 70 million people are facing hunger around the world in 2017. The primary causes include drought, military conflict, and lack of ability of nations to access food on the international market. Four countries — Yemen, Somalia, South Sudan and Nigeria — now face famine. And drought and conflict stricken Africa is the primary hot-spot for global hunger. Climate change has likely worsened this situation by adding to the intensity of droughts and heatwaves now affecting the region. In addition, past year droughts in places like Yemen and Nigeria helped to inflame present conflict and instability. Image source: Famine Early Warning Network.)
Additionally, conflict combined with the after effect of a 2014-2015 drought has disrupted food and water access in Yemen. Meanwhile, Nigeria’s falling purchasing power following a 2015 drought has rendered it unable to reliably procure food locally or on the international market.
These synergistic factors have forced plummeting food production and food security throughout Africa and nearby Middle Eastern countries. And now four nations — Somalia, South Sudan, Yemen and Nigeria — have been placed under a famine alert. In these countries alone, 20 million people face starvation and the world-over more than 70 million people are under threat from hunger.
The Climate Connection: Very Warm West Pacific = Drought in East Africa
La Nina is often identified as a period when rainfall in East Africa abates — producing an increased risk of drought. This cyclical African weather pattern is primarily produced by a pooling of warm water in the West Pacific that, in turn, alters atmospheric circulation patterns the world over.
(Very warm sea surface temperatures helped to produce a severe 2016 drought in East Africa. Somalia, which was particularly hard-hit, is now facing famine. Image source: Earth Nullschool.)
During 2016-2017, the La Nina was comparatively weak. However, sea surface temperature anomalies in the Western Pacific hit rather high readings over large ocean regions. The net effect to East Africa appeared similar to what would typically be experienced during a stronger La Nina event.
This cyclical climate event also occurred during a year when overall global temperatures were around 1.2 degrees Celsius warmer than 1880s averages. For 2016, overall temperatures in the drought impacted regions averaged between 0.5 and 2 C warmer than normal. And this added heat would have amplified any droughts that did form by increasing the rate at which moisture was evaporated out of soils and rivers. Furthermore, temperatures over the Western Pacific teleconnection zone also deviated by +0.5 to +2 C above average ranges. As a result of these prevalent warmer conditions, impacts related to human-caused climate change cannot be entirely ignored as part of the overall drought and food-stress signal.
Somalia Hit Hard
Among the four countries now facing famine alerts, the various climate and climate change related impacts appear most acute for Somalia. Back in 2011, another La Nina and associated warm western Pacific surface waters helped to produce a famine that killed 260,000 people. Now, just six years later, a record warm world and La Nina are serving up these severe conditions again.
Two rainy seasons failed back to back in the water stressed nation during 2015 and 2016. And from October through December of 2016, large parts of Somalia received less than 30 percent of the typical rainfall for the period. Now a national disaster has been declared as 6.2 million people (or about half the country’s population) is at risk from hunger.
This week, Somalia’s President Mohamed Abdullahi Farmajo issued an urgent call for aid:
“We must provide immediate and potential assistance to avert widespread starvation and death. I appeal to all donors to provide the necessary fund for immediate and emergency assistance.”
Conditions in Context — Climate Change Proliferates Drought, Food Insecurity
2017’s famine alert is Somalia’s second in six years and its third in 25. And the various famine alerts that are presently ongoing all occur in states that have suffered from drought and water stress in the past five years. Instability and conflict are often identified as the cause of food stress. But drought is a trigger condition under which multi-year instability and conflict can emerge (as we have so vividly and tragically seen in Syria). In this way, drought and conflict interact in a chicken and egg relationship to produce reduced food security. And it’s a situation that’s exacerbated by warming global surface temperatures.
Unfortunately, with global temperatures likely to increase by another 0.3 to 0.6 C over the next two decades, food stress and related instability are a rising risk for this and other regions of the world. More intense drought, shifting climate zones, and changing precipitation patterns all help to increase that risk. And, at this point, the various food crises the world is presently experiencing are difficult to divorce from it.