Forecast for Africa

In the summer of 2012, Zachary Dunn climbed onto the roof of a red-brick schoolhouse in Lela, a small village in southwestern Kenya. A crowd of children milled about on the ground, watching him attach a small weather station to the peak. It was the rainy season, overcast and cool enough for a long-sleeved shirt. Plots of maize, cassava and sweet potatoes near the school promised a good harvest.

Thinking it to be a teachable moment, the Oregon State University engineering student stopped what he was doing and looked at one of the kids below. “Do you know what this is?” he asked, holding the arm of one of the instruments. “Yeah,” said the boy. “That’s an anemometer.”

“I was blown away,” Dunn said later. “I thought, ‘Whoa, how did he know that?’ He was about 10 years old. OK, I realized you need to check your assumptions at the door.”

Dunn completed his work and paused to gaze at the surrounding landscape, a green-and-brown patchwork of farm fields, shrubs and trees. Lake Victoria (Nam Lolwe, to the local Luo people), the largest body of freshwater in the tropics, lay just over the horizon to the west. As a member of Oregon State’s Engineers Without Borders chapter, the native of Albany had come to Lela to improve the community’s access to clean drinking water. The students had helped the residents drill a new well and build a rainwater collection system.

The weather station was key to the project’s success. Linked to the cellphone network and the Internet and designed by Decagon Devices, a company in Pullman, Washington, it would enable students to keep tabs on conditions in Lela — solar radiation, rain, wind, relative humidity and temperature. Additional sensors in a water storage tank would tell them how much water was being stored for later use. If a pipe became clogged or a valve sprang a leak, they could detect the problem and arrange a fix.

“It occurred to me that this was a way to make sure that these development projects are sustainable,” says Dunn. “If you have these sensors that you can use to monitor a project, you can make sure it’s still working years after it was installed.”

Across the developing world, poorly maintained wells and water systems are a significant problem. It’s estimated that up to a third of the wells installed in Africa to provide drinking water have failed for lack of maintenance.

For Dunn, the project in Lela was a modest beginning, but the experience planted a seed that has grown into his dream job. After receiving his bachelor’s in engineering, he started a master’s in public policy and returned to Kenya with financial support from a Boren Fellowship (created by former U.S. Senator David Boren of Oklahoma to bolster international relationships). However, before he settled into an apartment in Nairobi and dug into his thesis project, he signed on as the East Africa field director of a new nonprofit organization, the Trans-African HydroMeteorological Observatory (TAHMO).

“Africa is going to be the most important continent for food production,” says John Selker. “That’s where the big potential is. One-third of the continent is primed to grow whatever crop you’d like to. This is a resource unequaled in the world. This will make Africa a leader in the coming century.”

Two professors, Oregon State hydrologist John Selker and Nick van de Giesen at the Delft University of Technology in the Netherlands, started TAHMO in 2010 with a grand vision: Transform Africa from being the world’s most poorly monitored continent for weather to being the best. They plan to install 20,000 weather stations across sub-Saharan Africa in a network that will give a badly needed boost to farmers, fishermen, businesses and water management agencies.

The technology they are using — no moving parts, highly precise, connected to cellphone networks, powered by a solar cell half the size of a credit card — could lead to a sea change in monitoring the weather in other parts of the world. And to develop homegrown expertise, they are challenging and training college students in Nigeria, Kenya and other countries to come up with their own weather monitoring innovations. TAHMO researchers at Oregon State and Delft include experts from Africa (Senegal, Eritrea, Nigeria, Ghana and Kenya) as well as the United States and the Netherlands.

Sustainable Technology

For most people, knowing the weather is a matter of convenience. It helps us decide how to dress or whether or not to take an umbrella to work. However, in places with frequent storms (think Oklahoma and Kansas in the spring), it’s a matter of life and death. On East Africa’s Lake Victoria, which experiences thunderstorms more than 200 days per year, an estimated 5,000 fishermen drown or are killed by lightning strikes annually.

And while storms can destroy farm crops through flood, hail or high winds, the slow and inexorable strangle of a drought can deal just as deadly a blow. On a trip to Africa in 1985, Selker saw firsthand what that meant for farmers and herders in Kenya and Somalia. He had gone there with his wife, ceramacist Laurie Childers (they had met at Aprovecho, the sustainable technology education center near Cottage Grove), to make fuel-efficient biomass cooking stoves. Childers was also developing a construction manual for small ponds to capture runoff.

“In rain-fed agriculture, you need rain every week, but with a storage pond like this, you only need rainfall once a month,” says Selker. The drought that year was severe, but farmers who had these small ponds were able to water their crops and feed their families.
It was an aha moment for Selker, who estimated that for about $1 billion, water storage ponds could be dug for every farmer across the Sahel, from Somalia to Mali. He returned to the United States to complete a master’s and Ph.D. in hydrology at Cornell, where he met van de Giesen. But the lesson he learned in Africa stayed with him: The right technology could make a profound difference in peoples’ lives.

Weight of Water

In 1991, Selker came to Oregon State as an assistant professor in the Department of Agricultural Engineering (now Biological and Ecological Engineering). Combining his bachelor’s in physics (Reed College, 1981) with expertise in the flow and measurement of water, he devoted himself to research on groundwater, pollution (nitrate contamination) and water temperature. He worked on water quality issues in Oregon, collaborated with scientists in Chile and developed techniques for environmental sensing with fiberoptic cables in Switzerland. It wasn’t until 2006 that he returned to Africa at the invitation of his graduate-school friend.

Van de Giesen was in Ghana looking at a new way to address a poorly measured part of the hydrologic cycle. What if, he wondered, we could determine the amount of rainfall intercepted by trees by precisely measuring how much their trunks are compressed by the weight of water? It is not just a matter of idle curiosity. Trees capture huge amounts of water, much of which evaporates back into the atmosphere, reducing how much filters into the ground, feeds rivers or becomes available for agricultural crops. An accurate picture of this process — known as “interception” — is critical to understanding water flows.

They were able to measure the compression of trees to within a micron, but testing the idea that trees could function as a type of water meter would require local weather information. “I asked Nick where we could get data on rainfall, humidity and temperature,” Selker recalls. “He said, ‘John, they don’t exist here.’”

Although there are many weather stations on the continent, many areas are not monitored, and few stations outside of South Africa report data in a timely manner. “Many of them send data by mail at the end of the month,” says van de Giesen, “and there are difficulties in sharing data from one country to another.”

The more they talked, the clearer it became: They could fill a gaping hole in Africa’s environmental knowledge by taking advantage of the ongoing revolution in electronic sensors and the rapid growth of cellphone networks. With a new generation of sensors, they could monitor the weather as it happens at a lower cost and with greater accuracy and reliability than is possible with conventional weather stations.

“It was kind of a pipe dream,” Selker says, “but think of this: The sensor in a wristwatch that measures barometric pressure is more accurate than the best barometric sensor available 50 years ago for any amount of money. And it runs on a watch battery for 10 years for $2.”

Accessible on Africa’s ubiquitous cellphone network, real-time weather data could provide fishermen on Lake Victoria with timely warnings about storms. It could enable public safety officials to move people out of harm’s way before a flood. It could enable crop insurance companies to make policies more accessible to farmers, thus setting the stage for badly needed increases in food production.

For help with weather monitoring technology, the hydrologists turned to Decagon Devices, the company that built the station installed by Zachary Dunn in Lela. Decagon specializes in electronic sensing of the environment. It calculates wind speed by sending an acoustic signal through the air and measures rainfall electrically as drops of water drain through a collection cup, one at a time.

It turned out that Decagon also had a plan for a new weather station network connected through cellphones, but the company hadn’t identified a market. “So we got excited,” Selker says, “and have been working with them for years, going step-by-step through the different sensors to validate them.

“But,” he adds, “the technology is kind of the toys part. Anyone can buy a weather station. Anyone can put it up, but keeping it running is the trick. Sustainability is really the critical part. How do we pay for it, and how do we organize it to stay running? We need to sell the data to companies and share it freely with governments and researchers for the public good.”

Building the TAHMO network across sub-Saharan Africa would take a business plan and a trusting relationship with every country in the region. “It was a real chicken-and-egg problem,” says Selker. “If you don’t have coverage in an area, you don’t have anything to sell. Where could we get started?”

Learning to Speak Swahili

In Nairobi, Dunn was considering how TAHMO could work most effectively in Kenya. He remembered what he had learned during the water project in Lela and talked with his friend Paul Olang’o, the son of Lela’s village elder who had also moved to the Kenyan capital.

“My time in Lela grounded my understanding of Kenya in this rural, agricultural experience,” says Dunn. “Lela is an agrarian community. It taught me that this is what Kenya is. Nairobi is a modern city of three million people where the electricity is on 24/7 and Wi-Fi is faster than what I had at home in Oregon. But Nairobi is not like most of Kenya. Two-thirds of the people in Kenya depend on agriculture.” To have a broad reach, TAHMO would need to serve rural farming communities.

To deepen his understanding of the culture, Dunn started taking Swahili classes. Kenyan officials speak English fluently, but by learning their language, he also showed them respect. He sent a letter to the Kenya Meteorological Department and was invited to give a presentation about TAHMO. Over a period of about six months, he and Kenyan officials developed a memorandum that would enable weather-monitoring efforts to go forward with the government’s approval.

The plan was relatively simple. Give weather data freely to the government and to researchers but sell it to businesses: crop insurance companies working with farmers, financial companies managing long-term investments, phone companies designing weather apps for their customers. Companies regularly buy weather data, which are critical for effective planning and development, says Dunn. (In the United States alone, the annual value of weather forecasts has been estimated at $30 billion.)

The agreement that TAHMO signed with Kenya in 2014 became the model for those signed in Malawi and Ghana. It has also inspired discussions with governments in Uganda, Nigeria and Rwanda. “We are going country by country. It’s a painstaking effort,” says Selker.

For van de Giesen, those relationships are fundamental to TAHMO’s long-term success. “On the ground, it’s African people who have to move this forward,” he says. “It needs to be an African initiative. In Nigeria, we had a sensor design competition, specifically targeted at Africa. People were so appreciative saying ‘Yes, we can make our own sensors.’ They have been taking the initiative.”

Growing Food

In the past year, TAHMO hired Gilbert Mwangi, a graduate student at Jomo Kenyatta University in Kenya who won the design competition in 2013. He has installed more than two dozen stations in Kenya, Uganda and Tanzania (mostly at schools; see sidebar), and others have been located in the Democratic Republic of the Congo, Nigeria, Ghana and other countries. TAHMO has received $1 million from the Global Resilience Partnership (sponsored by the Rockefeller Foundation, USAID and Sida, a Swedish development agency), to develop an early warning system around Lake Victoria in collaboration with Earth Networks, an environmental monitoring company.

Since weather data provide the basis for crop insurance, TAHMO is working with ACRE Africa (Agriculture and Climate Risk Enterprise Ltd.) to manage and expand its weather station network in Kenya and Rwanda.

At the top of Selker’s and van de Giesen’s agenda is the need to feed a growing global population. “When we’re done, monitoring the African climate will be an order of magnitude better than any other place in the world,” says Selker. “That’s our goal. There’s no other place in the world that has consistent instrumentation like this. There’s no other place that has uniform and dense spacing.

“Africa is going to be the most important continent for food production,” he adds. “That’s where the big potential is. One-third of the continent is primed to grow whatever crop you’d like to. This is a resource unequaled in the world. This will make Africa a leader in the coming century.”