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Notes from the Field

I have been working with a project focused on drought in Kenya for months using NASA satellite data and was excited to get a ground-based perspective of the country and meet fellow Earth Scientists in Nairobi, Kenya. My colleague Eric Anderson and I attended a week long course on the Quality Index Insurance Certification (also known as QUIIC), which provides methods to evaluate the quality of satellite-based indices for use in agriculture/pastoralist insurance.

The left image shows average NDVI over Kenya while the right image shows average NDVI during the 2011 drought period.

I’ve been working with SERVIR since November 2018 to support the development of a lower-latency vegetation index, inspired by Kenya Livestock Insurance Program needs. A lower-latency product can enable programs like these to provide relief sooner, potentially before total losses. The Normalized Difference Vegetation Index (NDVI) is currently used in this insurance program and provides a satellite-based measure of vegetation health, which can show how much forage is available for livestock consumption. When conditions are bad, the program is intended to help people through the season without experiencing devastating losses. 

Indices, such as vegetation health, can be monitored using satellites and provide a low cost way to detect things like drought, especially where field data is scarce and pastoralists may otherwise be uninsurable under traditional contracts. Index insurance programs are meant to promote farmer and pastoralist resilience, but if they are designed poorly they can actually leave people worse off. For example, if conditions are bad one year but the index fails to trigger payouts, farmers would be worse off had they purchased insurance and not received a payout. The information-rich course, led by economics experts from UC Davis (Michael Carter and Elinor Belami), helped us understand a different side of applying remote sensing to real world problems. We learned about the economics of insurance and evaluated the quality of using different indices compared to traditional insurance for a focus region.

Here we are on the first day of the course playing a game to explain risk aversion. People who are more risk averse choose an option that has lower risk, even though the choice may have a lower average reward.

It was a great experience to be able to see a different culture and meet so many people from different backgrounds. Our next mission is to bring what we learned in the course back to the SERVIR hubs and explore ways to apply it. Using methods to measure quality of an insurance index we can decide if index based insurance is appropriate for different regions.

The course brought together representatives from UC Davis, SERVIR hubs and the Regional 
Centre for Mapping of Resources for Development (RCMRD).

Belize is a small Central American country whose people pride themselves on trying to maintain a balance between development and conservation. I grew up in Belize City, near where the Belize River empties into the Caribbean Sea. The country’s landscape—covered by tropical forests and a network of rivers extending into the ocean—is fascinating, especially when viewed from the vantage point of space. I was able to return to Belize to join scientists from four organizations (Wildlife Conservation Society, the University of Alabama in Huntsville, the University of Georgia and NASA’s Jet Propulsion Laboratory) to kickoff research the likes of which Belize has never seen before. Our NASA-supported project, “Climate-influenced Nutrient Flows and Threats to the Biodiversity of the Belize Barrier Reef Reserve System,” (BZ-SDG for short), examines how satellite data can help with the Sustainable Development Goals (SDGs), a set of 17 goals agreed to at the United Nations’ General Assembly in 2015. BZ-SDG looks at how NASA Earth observation data can help with monitoring progress on two goals (SDGs 14 and 15), “life below water” and “life on land.” While BZ-SDG is the first NASA project focused specifically on Belize, it builds on NASA’s earlier work in Central America under the SERVIR program, implemented by USAID and NASA. The project is also a demonstration for the Earth Observations for the Sustainable Development Goals (EO4SDG) initiative.

View of the Belize River from the airplane as we were landing.

There is increased interest in using satellite imagery for monitoring coastal areas in Belize, following on a coastal zone management program that began in the early 1990s. The Belize Barrier Reef is the second longest coral reef system in the world, and local scientists want to know what impact activities on land are having on these reef ecosystems. Coral reefs are like forests of the sea, and are important for maintaining fisheries. A 2008 study found that coral reefs, in association with mangroves, contribute to between 12% and 15% of Belize’s tourism earnings. Sometimes plumes of sediments wash down the country’s river systems and can be seen by satellite images extending all the way out to the coral reefs. Activities inland were also suspected of contributing to  a large bloom of green algae off Belize’s coast in 2011.

As “eyes in the sky,” satellites can survey vast extents of land, as well as the seas (i.e. the ‘seascape’), showing us information about water quality using different parts of the spectrum of light. In addition to specific satellites that focus on color of river water and sea water, there are also ways to use satellite imagery to track changes within that water, like sediments flushed into the rivers by erosion occurring further inland, or chlorophyll caused by photosynthesizing organisms.

Left: A Landsat-8 image from October 2018 shows a sediment plume originating from the mouth of the Belize River, extending 8km out to sea. Right: Relatively clear waters shown in another image from the same satellite from May 2019.

Left: A March 2013 Landsat-7 image of what the water off Belize’s coast normally looks like, with the coral reefs in light blue. Right: An algal bloom in a June 2011 Landsat-7 image can be seen as an almost phosphorescent green.

Upon arrival to Belize, we were joined by Sol Kim and Rafael Grillo, two Ph.D. students from the University of California, Berkeley, to carry out these on-site validation measurements. Over a period of two days, our team collected water quality samples on a path extending from just off the coast of Belize City all the way out to barrier reef—a distance of 15km (approximately 9 miles) out to sea. By comparing what the satellites “see” with what is measured in the field, researchers can help improve how the satellites estimate water quality in Belize’s coastal waters.

Project co-Investigator Christine Lee (left) of JPL writing the label for a sea water sample being collected by co-Investigator Deepak Mishra (right) of the University of Georgia.

We also traveled a few kilometers up two sections of the Belize River: first, up the main channel (for a distance of 8 kilometers or 5 miles), and 10 kilometers (approximately 6 miles) up Haulover Creek, which divides Belize City north-south and is the final section of the river. Aside from the water samples collected, the Belize River “mangrove cathedrals”—stands of red mangrove (Rhizophora mangle) rising to about 20 meters (approx. 65 feet) in height—were also seen on the journey through Haulover Creek.

The interlocking canopies of red mangrove—reminiscent of church steeples—gave rise to the name “mangrove cathedrals.”

Locations of the 50 water quality samples collected on May 14 and 15, overlaid on top of a Landsat-8 image from May 20, 2019.

In total, 50 water quality samples were taken in the river and in the sea to determine sediment concentrations at each site. Additionally, using a hand-held sensor and a simple instrument called a Secchi disk, parameters like water depth, salinity, dissolved oxygen, pH, and temperature, were also measured. Locations of the 50 sample sites were geolocated using a handheld GPS receiver.

Rafael Grillo Avila of UC-Berkeley logging GPS coordinates, while Victor Alamina of WCS kept the boat steady.

On May 15, measurements were even taken at the same time as the Sentinel-2A satellite (from Europe’s Copernicus system) passed overhead! Unfortunately, the conditions were cloudy, so it wasn’t possible to estimate sediment concentrations from that imagery.

Copernicus Sentinel-2A image of Belize captured on Wed. May 15, when we were in the field; the red dots are the locations of the 21 water quality samples we collected that same day

Another fascinating part of the monitoring process is sampling in visibly tannin-rich river water near the mangrove cathedrals. Water could not be seen in different types of satellite images reviewed, including 30m Landsat imagery (NASA / USGS), 10m Sentinel-2 imagery (European Space Agency / Copernicus) or 3m Planet Labs Planetscope imagery. This is partly due to how narrow the river is, and mangrove trees overhanging the river, but it also means that it isn’t possible to use those types of images to examine water quality in portions of the Haulover Creek.

April 2019 Planetscope imagery of some of the study locations (Source: Planet Labs)

Calibrating the satellite-based estimates of water quality (from Landsat and Sentinel-2) will rely on measurements from the water quality samples collected. Since seasonal influences affect water quality,  this year’s sampling was timed to coincide with the end of the dry season. Additional water quality samples are planned to be collected during the wet season later this year, as well as next year’s dry season. Using this data, our team expects to work with local partner organizations like Belize’s Coastal Zone Management Authority & Institute to provide an interactive virtual dashboard that shows how water quality is changing across the coast over time. The country will be able to quickly detect when water quality events affecting Belize’s coral reefs occur with the dashboard.

This research is supported by NASA under cooperative agreement number #80NSSC19K0200. The project team includes Nicole Auil-Gomez, project co-Investigator Dr. Alex Tewfik, Myles Phillips, Victor Alamina, Ralna Lewis, and Deseree Arzu of the WCS, project Principal Investigator Dr. Robert Griffin and co-Investigator Dr. Emil Cherrington of UAH, project co-Investigator Dr. Deepak Mishra of UGA, project co-Investigator Dr. Christine Lee of NASA JPL, and Ph.D. students Sol Kim, Xiaowei Wang, and Rafael Grillo Avila of UC-Berkeley. Dr. Cindy Schmidt, Associate Program Manager for the Ecological Forecasting program of the NASA Applied Science Program, also participated in the field visits.

I couldn’t help but notice Dubai as the land of the largest. Aside from being the largest city in the United Arab Emirates, Dubai is home to Burj Khalifa (the tallest tower in the world), the second-biggest mall (depending on how you measure), and a series of massive artificial islands in the shape of palm fronds and continents along the country’s coastline. Following this trend, it was fitting for the city to host a major consultative workshop on probably the largest cross-disciplinary subject area: land cover and land use change. Mapping and monitoring landcover (forests, rangelands, cropland, & settlements) helps us understand change over time and is critical to maintaining healthy ecosystems that can provide carbon sinks for limiting greenhouse emissions, arable land for food security, and habitat for wildlife. Additionally, land cover dictates how water flows across the land surface and has a direct impact on water quality and water resources.

A night view of Burj Khalifa, the tallest building in the world at 2,717 feet (approx. 828 meters)

The two-day workshop focused on the Afghanistan National Land Cover Monitoring System (A-NLCMS), a customized service for annual land cover mapping and change analysis. Using remote sensing inputs from Landsat and Sentinel-2 satellites, a standard methodology, and consistent datasets, A-NLCMS is able to address gaps in regional land cover data. The service is a collaborative effort, co-developed by two regional instances of SERVIR: the Hindu Kush-Himalaya and Mekong, with additional support from the United States Forest Services (USFS) and SilvaCarbon.

The workshop brought together a high-level delegation from Kabul, including Director Generals from the Ministry of Agriculture Irrigation and Livestock, Afghanistan Meteorological Department, National Environmental Protection Agency (EPA), Deputy Director Generals from the Ministry of Energy and Water and the National Statistics and Information Authority, to name a few.

Workshop deliberations were fruitful and succinct, achieving the main objectives of finalizing the methodology and approach of the A-NLCMS, while defining the roles and responsibilities of both SERVIR and relevant Afghan ministries going forward.  This consultative process is vital to understand needs and current capacities, and allows for the design of innovative (and regionally appropriate) scientific solutions. All in all, the workshop was exemplary of how SERVIR works: bringing together people from diverse backgrounds to address complex environmental issues around the globe and co-develop solutions with local decision makers and stakeholders.

Though the trip was short, the camaraderie the workshop facilitated resulted in great memories and experiences. We enjoyed a night on the town where we stumbled upon the world’s largest (of course) choreographed fountain system: the 30-acre Dubai Fountain. Pictured above are the Freedom Divers, part of an indoor water feature cascading down all three stories of the Dubai Mall.

It’s a true pleasure to be a part of a project that brings people together across so many cultures, agnostic of borders, to address pressing issues. The experience reminded me a of a lesser-known world record held by the country: in December 2014, to celebrate the 43rd National Day of the UAE, people of 117 different nationalities came together to sing the UAE’s national anthem, creating a world record for the most nationalities to come together and sing a national anthem at one time.

A desert sunset to cap off a fun and successful trip.