Africa

East Africa drought: ‘Climate change is making La Niña impact severe’

Climate change is pushing countries like Ethiopia, Kenya and Somalia into a famine as they face their fifth consecutive deficit rainy seasons

 
By Richard Mahapatra
Published: Tuesday 14 June 2022

East Africa is experiencing its worst drought spell in four decades. The last four rainy seasons have been majorly deficit and the upcoming one in October-December is forecast to follow suit, making it an exceptional situation.  

The last rainy season — March to May — was the driest one in over 70 years for Ethiopia, Kenya and Somalia. In the first week of June, in a joint statement by agencies like the Intergovernmental Authority on Development Climate Prediction and Applications Center, the Food and Agriculture Organization, the Famine Early Warning Systems Network (FEWS NET) and the World Food Program (WFP) warned the situation leading to a famine not seen in recent history.

Already 7 million livestock have died and some 20 million people are enduring severe hunger, according to WFP.

The exceptional weather situation is attributed to La Niña, a natural large-scale cooling of ocean surface temperature in the central and eastern equatorial Pacific Ocean. This is causing the dry weather and high temperatures in East Africa. 

But this spell of the climate event has been protracted unusually, as the World Meteorological Organization (WMO) said in its bulletin on June 10, 2022. It started in 2020 and will continue to persist through 2022, with a high possibility of continuing into 2023. 

In this case, it would be the third such spell in half a century. The WMO in its statement said the naturally occurring climate event is having unusual impacts such as though “La Niña has a cooling influence, temperatures are continuing to rise due to global warming”.

In July-August 2011, a strong La Niña resulted in the worst drought in 60 years in East Africa and the UN declared a famine in the region after a gap of 30 years. The current situation is worsening to hit that level.

Close to half of Somalia’s population face crisis-level food insecurity, which might lead to thousands of deaths due to starvations. Adam Abdelmoula, deputy special representative of the secretary-general of the United Nations, resident and humanitarian coordinator, said: 

Somalia is in danger of entering an unprecedented fifth consecutive failed rainy season. Famine cost the lives of 260,000 Somalis in 2010-2011.This cannot be allowed to happen again in 2022.

In Ethiopia, over a million livestock have died due to crop loss and dry weather, while an estimated 7.2 million people are in need of immediate food aid in the southern and southeastern regions. 

In Kenya, the number of people in need of assistance has risen more than four times in less than two years.


Read more: In Somalia, drought forced more than 450,000 people from their homes this year


A group of earth scientists from across the world has been forecasting with precision on the descent of famine-like situations to help governments and aid agencies to direct reliefs through FEWS NET. 

This unit of the United States Agency for International Development (USAID) was set up in 1985 in response to the famine that hit East and West Africa and killed more than a million people, particularly in Ethiopia. 

The Climate Hazards Center (CHC) in UC Santa Barbara is one institution that equips FEWS NET with precise data on climate change, its impacts and famine. CHC focuses on East Africa, the world’s most drought-prone areas.

Chris Funk, the director of CHC and who recently forecast as part of the joint statement of multiple agencies on the dire state of situation in East Africa, has been assessing the frequent droughts in the region and their links to climate change. 

“In 12 out of the past 24 years, there have been La Niñas,” Funk said, adding, “I am very confident that the circulation disruptions they cause are being amplified by climate change.” 

He, along with other scientists, predicted the 2010 famine in Somalia. But he has a grievance: Even if the forecast is precise, what if we don’t act on it. 

Funk spoke to Down To Earth on the unfolding crisis in East Africa, the role of early warning and the importance of using it for averting human tragedy. Excerpts:

Richard Mahapatra: Four rainy seasons have failed in East Africa, precipitating a crisis like never before and an event seen after 40 years. How do you explain this as a climate event?

Chris Funk: Understanding the climate of eastern East Africa begins with understanding its close connection to the movement of heat energy in the Pacific Ocean. 

Under normal conditions, the Pacific Trade Winds push heat energy towards Indonesia. 

The area surrounding Indonesia (‘The Warm Pool’) has the warmest, rainiest weather in the world. The very warm waters of this region create a low-pressure system that pulls in moisture from the surrounding atmosphere. This is why East Africa tends to be, on average, dry. 

There are year-to-year variations in this pattern, though, as the Pacific Trade Winds get stronger or weaker in response to ocean temperatures.

The next thing to understand is that climate change has caused — and is causing — the heat in the oceans to increase rapidly. 

The current droughts have been produced by an interaction between natural climate phenomena called ‘La Niña’ and climate change. Naturally occurring La Niñas are associated with cool sea surface temperatures in the east Pacific.

The impact of La Niñas is increasing for eastern East Africa, because of human-induced warming in the oceans. When there is a La Nina event, the west-to-east winds over the Pacific Ocean intensify, pushing the 'extra' heat in the Pacific into the western Pacific. These warm waters cause the rainfall around Indonesia to increase. 

To the west of this precipitation one finds dry, hot, rising air over East Africa, which reduces total rainfall and increases air temperatures. 

The current multi-season drought has been produced by a natural multi-year La Niña event, amplified by climate change and expressed as exceptionally warm west Pacific sea surface temperatures and exceptionally warm air temperatures over East Africa.

RM: The La Nina period is unusually long this time. Will you elaborate on how and why this climate phenomenon is becoming more pronounced and a threat to Africa?

CF: There are two aspects to this question: La Nina frequency and La Nina intensity. Regarding the first aspect, it is very important to note that La Nina events have been very common since 1998. Over the past 25 years there have been 12 La Nina events and there is currently about a 54 per cent chance that we will see another La Nina this October. 

While there is a lot of debate on this in the climate community, many observational studies and my own research has suggested that the climate is becoming more La Nina-like. 

Another aspect that I have a great deal of confidence in is that when a La Nina happens, now, its intensity is greatly amplified by human-induced warming in the western Pacific. 

RM: You have mentioned that La Nina’s impact of low rainfall has aggravated after 1997. Will you elaborate on this?

CF: After a giant 1997-98 'El Nino' event (associated with exceptionally warm waters in the eastern Pacific'), sea surface temperatures in the western Pacific jumped up. There the average state is very warm, and they become even warmer during and right after a La Nina event. 

As described above, these warm waters amplify the ability of La Ninas to reduce East African rains.

The impact of this has been especially marked on the March-to-May rains. This sets up a very dangerous, but also very predictable, pattern of back-to-back droughts in October-November-December and March-April-May.  


Read more: Fifth-hottest May again drives home reality to warming world


This type of sequence produced devastating sequential droughts and food crises in 2010-11 and 2016-17. 

Tragically, the current two-year La Nina has created an exceptionally dangerous series of four droughts, capped by what seems likely to be the worst March-April-May 2022 season on record.

RM: For over 20 years, you have been forecasting and alerting droughts through CHC. What is the trend that you observe in Africa?

CF: I see two major “trends”: More extreme dry and wet rainy seasons, driven by more extreme changes in sea surface temperatures, as described above; and more extreme air temperatures, which can desiccate crops and pasture lands, while also having negative impacts on human and livestock health. 

Furthermore, as we are seeing now in the Horn of Africa, these two sources of risk combine, such as when we get droughts in dry regions like East Africa. 

But, I am also very worried about human impacts associated with extreme “humid heat”. More intense dry / hot spells can drive farmers into cities where they may be exposed to more extreme heat. 

But, in general, it is important that 'trends' are really produced by extreme events, events that we can monitor and predict. We are not powerless in the face of climate change.

RM: Your forecast and alerts are a great resource to avoid a human crisis. How do you do this?

CF: CHC has two main types of resources — global rainfall estimates and tailored forecasts. The first category of information is very widely used in what is known as the Climate Hazards InfraRed Precipitation with Stations (CHIRPS). 

In the first three months of 2022, 1.3 million CHIRPS files were downloaded from 4,800 unique internet protocol (IP) addresses — a total of 31 terabytes of data. 


Read more: Nearly 10 million children in Horn of Africa in ‘greatest danger’ due to drought, says UNICEF


We also have CHIRPS-compatible 1-to-16-day weather forecasts that are updated daily, and longer lead “sub-seasonal” weather forecasts as well. 

These are great products that are used by many agencies to monitor and manage climate risk. The rainfall and weather forecasts can be combined, providing a powerful way to rapidly assess extreme droughts. 

A terrifying example is in a May 27, 2022 FEWS NET Somalia alert, suggesting that much of Somalia is likely to receive extremely poor March-April-May rainfall. 

Despite our improvements in monitoring and forecasting, we are fearful that humanitarian responses will be insufficient, given the severity of the food security situation.

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