Interview | Unpredictable rains erode food security gains

Farmers in southern Madagascar count on predictable weather to grow staple crops: maize, sweet potatoes, rice.

Typically, they sow their fields in September in anticipation of the rains – which used to start in October and continue through February or March.

Climate change, though, is shifting rainfall patterns in southern Madagascar: Now the rains come later and fall harder. It’s not that the volume of water varies radically, but the timing can push a vulnerable population into crisis.

“Crops need sufficient water for a long enough period. You don’t want all that water to come in one big burst. But what we’re seeing is a shift in the timing and seasonality of rainfall – just as climate models predict in response to global warming,” explains Peter Huybers, chair of the Department of Earth and Planetary Sciences, of research he has published with colleagues in data science, nutrition, and climatology.

“So, if you’re a farmer, the growing time for your crop shortens before the dry season comes again. Your seeds become less viable; you lose your entire crop.”

Rice accounts for almost half the caloric intake of the average person in Madagascar, where 42 percent of small children are underweight. In the isolated south, cut off from global trade, there is little irrigation, few paved roads, ports or other infrastructure.

“If the harvest is poor, you see the prices in the market spike right away,” says Huybers. “These are people who depend upon local food production.”

There are also global trends toward high food prices and upticks in shortages.

“Until around 2012 we had this optimistic notion that maybe we could eradicate severe famine altogether, maybe by 2030. This was one of the UN Millennium Development Goals. Then we saw a plateau and since that time food insecurity has been climbing again,” Huybers says.

Climate change is but one explanation for spreading hunger. The Covid-19 pandemic, increasing conflict – these contribute to shortages as well. But disentangling the causes and effects is not straightforward.

Consider an example from northern Nigeria: As rainfall patterns change, goatherds are moving their flocks earlier in the season because they don’t have enough feed. They sometimes relocate their animals into areas where farmers have not yet completed the harvest, triggering land-use conflicts in a region already seeing increasing poverty and militancy.

“We know the climate is changing, and we expect it is playing a role in conflicts and food insecurity, but often the data is thinnest in the places where issues are most dire, making it hard to draw out long-term patterns,” says Huybers.

“It’s great to have new data. But if you’re interested in climate change, you need to place it in context. A lot of what we do is try to figure out how to piece together data sets that do exist, and then to meld them with the better data that we tend to have more recently.”

“One of the projects that we are now working on, sponsored by Amazon Web Services and the Harvard Data Science Initiative, is to build a global database of agricultural yields at detailed, sub-national levels. The database will be freely available and will help in determining the patterns and historical causes of food insecurity.”

Co-producing solutions

Some observers may think solving a food crisis means helping communities grow different crops, but Huybers cautions against dictating adaptation strategies from the outside.

“Food is an extremely important part of most social structures. And the notion that you could just come in and substitute with something else is, I think, overly facile. But at the same time, if there’s not enough to eat, that creates a dire kind of emergency that that does need to be met in some way.”

He and his colleagues are working with Madagascar’s Ministry of Public Health to better understand the needs of local communities and co-produce solutions.

“The reality is this could get worse going forward. And you need to prepare for an even greater hardship growing traditional crops. So, then you start to ask, ‘what kind of crops would be viable? How do you empower local people to figure out how they want to manage them?’” Huybers says. “What we have been trying to do is work with people locally to help them understand the science as best we can understand and communicate it, and then see if we can empower them to develop solutions.”