National Drought Mitigation Center


NDMC visiting student brings international insight on crowdsourcing drought data

July 26, 2022

Marleen Lam, a visiting student from Wageningen University, spent several weeks at NDMC this spring for her master’s research, during which time she was able to visit Rocky Mountain National Park in Estes Park, Colorado. (Photo by Michelle Margraf)

“There are so many things that are different,” said Marleen Lam, comparing Nebraska and the Netherlands. During her six-week visit, she managed to take in iconic experiences such as the baseball College World Series in Omaha, high school rodeo finals in Hastings and Lincoln’s bike trails, which reminded her a little of home.

Lam, a student at Wageningen University in the Netherlands, spent time this spring in Lincoln at the National Drought Mitigation Center doing research for her master’s in International Land and Water Management. Her thesis looks at what motivates people to submit observations to NDMC’s Condition Monitoring Observer Reports (CMOR) database.

Though Lam had never been to the U.S. before, this was not her first experience researching how different countries respond to environmental challenges like water scarcity and drought. Her undergraduate degree was also in International Land and Water Management at Wageningen. During that time, she spent three months in Tanzania, looking at whether it would be feasible for farmers there to use solar-powered pumps for irrigation.

Her experiences in Tanzania inspired Lam to pursue graduate studies. “I wanted to combine the technical aspects of water with the more social ones,” said Lam of her decision to undertake two different master’s degrees. Her first, completed this past January, was a more technical degree to give her hands-on experience with programming and modeling.

For that first master’s, Lam focused again on East Africa, Kenya specifically (because of the Covid-19 pandemic she was only able to return in spirit this time). She combined different indicators of drought, like the Standard Precipitation Index, with measures of drought impacts collected by the National Drought Management Authority. “The goal was to see if you can forecast drought impacts based on drought indicators,” Lam explained. The impacts she looked at included many of those experienced here in the U.S., like livestock deaths and crop losses, as well as ones more common in developing countries, like food insecurity and malnutrition.

Lam’s research in Kenya relied on machine learning techniques that were new to her. It was also her first foray into the drought world. “I was triggered a bit by drought because you hear it all over the news,” said Lam. “I mean it’s a hot topic. It’s everywhere, including in the Netherlands.”

That last statement may come as a surprise since the Netherlands is better known for flooding than for water scarcity, but Lam explains that drought is a growing concern there partly, in fact, because of the country’s flood management efforts. “Our water system in the Netherlands is really based on quick drainage, so all the water coming in should be as quickly drained to the sea as possible because of the risk of flooding,” Lam explained. “But now, you have more peak flows and long periods without rain, and there’s not enough water because it’s so quickly drained.” As water levels drop, she adds, salted water can intrude farther upstream at the mouths of big rivers, causing problems for agricultural producers.

Once she was in the drought world, Lam’s second master’s thesis came together quickly, facilitated by a connection between her advisor and Kelly Helm Smith, assistant director of the NDMC, who is leading development of the CMOR system and serving on Lam’s thesis committee. “What’s funny about the drought world is that everyone knows each other!” Lam laughed.

During her time at NDMC for her second thesis, Lam distributed a survey to past contributors to the CMOR database to understand their motivations for reporting on their local conditions. “CMOR wants to have more regular observers, not only in drought time,” explained Lam. “So, you need to look at motivations or drivers for people to report so you can have sustained participation.” Her survey included both open questions and motivational statements with which participants could agree or disagree. Her goal, Lam explained, was to both understand why people are reporting and what they need to report more regularly.

Lam received hundreds of responses to the survey, and she’s still analyzing the data, but she says that several themes have emerged. For example, the explanations participants gave most frequently for why they contributed included getting officials and U.S. Drought Monitor authors to better understand local conditions and trying to increase the likelihood of financial assistance.

Lam hopes that by understanding why people are reporting to CMOR, the center may be able to recruit more regular observers and improve the availability of data on conditions year-round, not just during drought. She also hopes that it will provide insight on how to integrate CMOR with similar databases like the Community Collaborative Rain, Hail, and Snow Network, a volunteer-based weather monitoring network.

Her work in Nebraska, Lam adds, is also part of a larger effort in the field to look at these issues internationally. “Not all countries have the same kind of country-level drought impact database that the U.S. does,” Lam said. Collaborators in the Netherlands are trying to build crowdsourced monitoring platforms like CMOR in places like Brazil, and Lam’s efforts are helping different countries share best practices with each other. That kind of international collaboration will become even more important in the future as drought conditions become more widespread and severe.

“Every event highlights the topic of water and drought,” said Lam. “It’s so relevant nowadays.”

-- Leah Campbell, NDMC Communications