Earth Matters

NASA Data Helps Assess Landslide Risk in Rohingya Refugee Camps

November 20th, 2019 by Lia Poteet, NASA Earth Science Division Applied Sciences Program

Camp managers and other officials overseeing Rohingya refugee camps in Bangladesh are now incorporating NASA satellite observations into their decision-making. Information like daily rain totals can help inform how to lay out refugee camps and how to store supplies. The goal is to reduce the risk to refugees from landslides and other natural hazards.

NASA and Columbia University scientists and staff survey efforts to halt additional land loss at a Rohingya refugee camp in Bangladesh.  Credit: UN Development Programme/Eno Jonathan

Since August 2017, more than 740,000 Rohingya refugees have fled from Myanmar (Burma) to Bangladesh. Many of them have sought shelter in camps in the hilly countryside, where landslide risks are greatest. When refugee camps were built in the southeastern part of the country, many plants and trees were removed — taking with them the roots that could hold the soil in place and help stabilize the landscape when heavy rains come.

Increasing this danger is Bangladesh’s intense monsoon season. Approximately 80 percent of the country’s yearly rain falls from June to October, bringing with it an increased risk of flash flooding and landslides. For instance, July 2019 storms dropped 14 inches of rain in just 72 hours, causing 26 landslides in Rohingya refugee camps around Cox’s Bazar, Bangladesh. One person was killed and more than 4,500 others were left without shelter.

“We have little information on landslides,” said Hafizol Islam, who is in charge of one of the most densely populated camps at Cox’s Bazar. “It is unpredictable for us and can happen at any time.”

Now Islam and other camp managers have access to maps and a website (updated daily) that provides near real-time NASA data on land use, rainfall, and elevation. Data come from the Global Precipitation Measurement (GPM) mission and the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on NASA’s Terra and Aqua satellites, among other sources. Taken together, these maps and data provide a clearer picture of when and where landslide hazards are concentrated.

“With landslides, flash floods, and rapid development, the terrain of these camps is constantly changing,” said Robert Emberson, a postdoctoral fellow at NASA’s Goddard Space Flight Center.

Tarps help prevent rainfall from infiltrating the soil and destabilizing the hillside.
Credit: UN Development Programme/Eno Jonathan

Emberson and other researchers from NASA’s Earth Applied Sciences Disasters Program and Columbia University’s International Research Institute for Climate and Society (IRI) are using new approaches to work alongside humanitarian end-users and develop products to address pressing needs in vulnerable settings. The partnership seeks the feedback of the local people affected and develops maps based on their input.

“We need to understand if, why, and when existing risk information is being used,” said Andrew Kruczkiewicz of IRI, one of the principal investigators of the project. “This strengthens the development of data services for humanitarian emergencies, where decisions and priorities change rapidly. Working in teams that bridge traditional professional and disciplinary boundaries gives data and climate scientists the opportunity to learn more about decision-making in specialized contexts.” 

The need for coordination is pressing. Bangladesh has seen steadily increasing rainfall totals over the past 50 years. Climate change is making monsoons in Asia more extreme, and it may be doubling the likelihood of extreme rainfall events even before monsoon season begins.

The partnership with NASA and IRI helps the UN agencies to assess risks like landslides or flash flooding and supports the disaster management in a scientific way to save lives and reduce damages in the refugee camps,” said Cathrine Haarsaker, a project manager for UNDP Disaster Risk Management.

Refugee camps built in the Bangladeshi hillside are vulnerable to sudden landslides.
Credit: UN Development Programme/Eno Jonathan

Emberson said seeing the camps in person brought home the importance of connecting with the people on the ground. “Working with satellite data can sometimes feel quite abstract and separate from the people within the images,” he said. “Visiting the camps not only helped us understand more about the specific problems associated with landsliding to help improve our models in the future, but also drove home the human side to this disaster, emphasizing the urgency of our work.”

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