USGS Expert Explains How Global Warming Likely Contributes to East Africa’s Brutal Drought

Somalia’s “mis-government” has turned a brutal drought into a horrific famine. But “if it weren’t in drought, it wouldn’t be in famine,” as Dr. Chris Funk, one of the world’s foremost authorities on East African drought explained to me in an exclusive interview today.

And Funk’s work provides strong evidence that global warming has exacerbated the drought.

Funk, a US Geological Survey scientist and founding member of UC Santa Barbara’s Climate Hazard Group, deserves our attention because he is “part of a group of scientists that successfully forecast the droughts behind the present crisis,” as he explained in an August article in Nature.

In Dadaab in northeastern Kenya, the IRC gives fortified food to malnourished young children whose families are fleeing drought and famine in Somalia. Photo: Peter Biro/IRC

You might assume bloggers who write about East Africa — confusionists who falsely assert that “Those who are familiar with Somalia’s recent history and current state of affairs do not mention climate change as a relevant factor to the country’s latest tragedy” — would actually read the relevant scientific journals. But I find again and again that many people writing on the subject just don’t know what they’re talking about or even bother to spend even a minute or two googling the subject.

I have been reviewing the literature on drought in the past few weeks for a major article on Dust-bowlification invited by a leading science journal. It will be published next week!

It seems increasingly clear that global warming is exacerbating the East African drought in a number of ways. As Funk explained to me, the sea surface temperature [SST] rise in the Indian Ocean and Western Pacific in recent decades are “well-correlated with global temperatures.” This is an area where “models and observations agree.”

Funk examined the historical data to show that those rising SSTs have already had serious consequences for East Africa — in a 2010 journal article he co-authored, “A westward extension of the warm pool leads to a westward extension of the Walker circulation, drying eastern Africa.” Here is how Nature summarized its findings in a January piece:

Ask farmers about rain, and they will tell you that the timing matters more than how much falls in a given year. In Eastern Africa, the months of the “long rains” or “belgs” are between March and June.

A new study in the journal Climate Dynamics suggests that these months will be much drier in the future in Kenya, Ethiopia and other East African nations because of climate change. Some 17.5 million people in the Horn of Africa already face food insecurity in the region, with stagnating agricultural production, population growth and recent drought….

Scientists from the U.S. Geological Survey and the University of California, Santa Barbara, studied the flow of air currents over the Indian Ocean.

Over the past 60 years the Indian Ocean has warmed rapidly due to greenhouse gas emissions from human activity. The warmer Ocean heats up the air above, causing it to rise until it hits a cooler patch in the atmosphere. At that point, the hot air condenses and falls as rain (the process of convection). Unfortunately, the rain falls in middle of the tropical Indian Ocean and not over land. This region is part of a global atmospheric current called the Walker circulation.

The air, which has now lost its moisture, flows westward and descends over eastern Africa. The winds bear little rain.

Scientists say that between 1980 and 2009, oceanic heating has reduced precipitation over eastern Africa during the vital “long-rains” season.“While there appear to be many factors that govern interannual variability in east African long-rains precipitation, convective activity during [the March to June season] has steadily declined in eastern Africa for the past 30 years as the convective branch of the Walker circulation has become more active over the Indian Ocean,” the paper states.

Funk said to me, “I think we’re already seeing the impacts from climate change” in the area.

It is important to note that Funk’s work, and other recent work, strongly suggests that many IPCC model predictions of increased precipitation in the region were incorrect:

Conventional modeling suggests that the tropical Walker circulation will become weaker due to climate change, resulting in more rainfall in eastern Africa. In the IPCC report, 18 out of 21 models predicted greater precipitation in the region. But recent studies, including this one, argue for a strengthening of the Walker circulation. This study uses observational data to show that the Walker circulation has extended westward, which makes precipitation more likely over the Indian Ocean and droughts the norm in eastern Africa.

Funk considers it a “first-order impact of global warming” that SSTs will continue to rise. He warned in his piece, “If the climate continues to tilt toward an intensified Walker circulation, or a westward extension of its western branch, rainfall should continue to decrease in the most food insecure region of the world.” In short, things are likely to “persist or intensify” in the coming decades.

Funk’s analysis stems from his work with the Famine Early Warning Systems Network, which was set up by the US Agency for International Development to help policy-makers prevent humanitarian disasters.

As he explained in the August Nature article, “We thought trouble was coming”:

Last summer, our group was meeting when a La Niña weather system was forecast. We knew that such an event could bring trouble, and we issued an alert that East Africa might experience severe droughts.

We based this conclusion on information from three sources. First, we knew that La Niña events are commonly associated with weakened rains in the Horn of Africa from October to December.

Second, from work on the ground, we knew that persistent poor rains at the end of the past decade, combined with high food prices, had weakened the population’s resilience to food emergencies.

And third, research has linked warming in the Indian Ocean as a result of climate change to drying of March-to-June rains in East Africa. This warming has intensified the negative impact of La Niña events; it was the chance that both the autumn and spring rainy seasons could be affected, back to back, that really concerned us.

Sure enough, the autumn 2010 rains were poor, or failed completely. The outlook for famine or survival then rested on the spring rains. April came without rain. May came without rain. And we feared the worst.

A key point I and others have made over and over again is that the most extreme weather occurs when climate change compounds the natural variability of the climate. In this case, global warming appears to be intensifying the impact of the La Niña.

But you also see that the long-term drying — persistent poor rains at the end of the past decade — have contributed. Again, climate change has contributed to the underlying problem.

It is also true that the rise in temperatures worsens any drought, by drying out the soil. I will discuss that in greater length in a later post.

And, of course, one of my favorite recent topics of 2011, the high food prices of the past year, also makes the situation worse. As now seems clear, those high food prices have been driven, in part, by extreme weather — see Washington Post, Lester Brown explain how extreme weather, climate change drive record food prices and my various posts on “food insecurity.”

These high food prices are most likely going to get even higher in the coming decades, as population pressures collide with climate change — see Oxfam Predicts Climate Change will Help Double Food Prices by 2030: “We Are Turning Abundance into Scarcity.”

Funk explained in his piece what high food prices mean right now:

The situation on the ground quickly deteriorated. FEWS NET runs a food-price tracking system that showed that the price of maize (corn) in Kitui, Kenya, had soared by 246% in 12 months. And the value of a goat in Bardera, Somalia, usually sold to buy grain, had halved. Satellite measurements of vegetation health tracked the emerging drought in disturbing detail. FEWS NET put out a second alert on 7 June that warned: “This is the most severe food security emergency in the world today, and the current humanitarian response is inadequate.”

Two months on, the grim statistics show that the massive crisis is outstripping the international resources available to address it. Famine conditions are expected to spread farther across Somalia, and large areas of Kenya and Ethiopia could see food availability fall to crisis levels. In all, some 11.5 million people across East Africa need emergency assistance.

Funk agreed with me that the fact that Somalia is a failed state is a major reason that a brutal drought has turned into a devastating famine: “No doubt, the most important thing, is the mis-government,” as he called it. But the point is that a “climate-driven drought set up the conditions where mis-governance could lead to catastrophe.”

One final point. It’s true that Somalia’s mis-government has meant that the drought has had a more severe impact on Somalia than surrounding states. And it’s true that planning for the drought has helped alleviate the famine in neighboring countries. But it hasn’t eliminated the danger in those countries.

As Dan Glickman, former Agriculture Secretary, and Dr. George Rupp, CEO of the International Rescue Committee, explained last month:

After the last East African famine in 2002, leaders had the insight to invest in long-term programs that have delivered astonishing results, including the Famine Early Warning System Network. As Secretary of State Hillary Clinton recently noted, the number of Ethiopians at risk of starvation in that previous famine was 13 million, while in the midst of today’s crisis, that number has been slashed by more than 60 percent to 5 million.

So, no, even Ethiopia has not escaped the threat posed by this drought. There are still 5 million at risk of starvation in that country alone.

The bottom line is that leading experts have concluded that global warming is exacerbating the East African drought, they used that knowledge to accurately predict the current drought, and they warn that unrestricted emissions of greenhouse gases pose a grave threat to the food security of the region.

The confusionists who try to muddy the waters try to turn every serious discussion about the contribution of global warming to some current impact on humans, like this drought, into “you said global warming caused the problem and that isn’t true” or some such misrepresentation. They seriously undermine efforts of scientist like Funk to inform the world community of what’s happening now and what’s likely to happen in the future so that we can plan ahead.