SnowEx: Little Blogs from the Prairie – Part 1

Like so many other things, NASA’s SnowEx 2021 looks a little different than usual this year. But one thing is business as usual, and that’s the participation of undergraduate and graduate students.

Students play a pivotal role in SnowEx, from suiting up for data collection to crunching the numbers afterward. The field sites become a classroom for the students too – as they measure, record, process and analyze real data, they learn skills for their own research work.

We invited some of the students from Montana State University to share their experiences in this year’s campaign at the Central Agricultural Research Center (CARC) site. In addition to sharing what their typical days in the field look like, they shared some of the new experiences and discoveries they’ve had, and what they’re enjoying most.

Dr. Eric Sproles, Assistant Professor of Earth Sciences, Montana State University, Site Lead

Wow – this NASA SnowEx project has provided some amazing opportunities for hands-on learning for students and investigators alike. The snow-centric research at Montana State University has primarily focused on mountain snowpacks. Working in the prairie is different in many ways. First, it is much more variable than I imagined. Because of wind and vegetation, snow drifts can be over 3 feet deep in one location, and only 20 yards away you find bare ground. This allows you to really think about the effects of wind and vegetation in this food producing region of the world.

Secondly, measuring the snow in these areas is incredibly challenging, and makes you rethink the way you usually do things. Being forced out of your comfort zone has helped broaden my perspective as a scientist and mentor. We have some amazing students at Montana State, and in these types of hands-on environments, I think I learn as much from them as they do from me. 

Leading this SnowEx project has allowed me to better connect with fellow SnowEx Leads, and also other scientists from across the United States with an interest in prairie snow. These professional relationships underscore the value of team-based approaches to big-picture science.

Andrew Mullen, Master’s Student in Earth Sciences, Montana State University

The 2021 SnowEx field campaign has been a unique experience because I have never before participated in such a widespread, coordinated field data collection effort with so many different moving parts. Although we are physically distanced from the other research groups, it feels like we are part of one cohesive effort with the same objectives in mind. We are collecting a vast array of data types using a variety of methods, and I have enjoyed thinking about how we can link different types of data to answer specific questions. Our work here feels meaningful because this data is being used to develop and validate tools and methods that will improve how we monitor snow across the globe for years to come.

My role at the CARC field site has mainly been in conducting UAV-based broadband albedo (reflectivity) surveys of our 1 km x 1 km study area. With these UAV flights, I am mainly interested in observing the spatial variability in albedo across the field area that is composed of many different types of crop cover and microtopography that have a significant impact on the distribution of snow and snow properties. I have also been a part of the manual snow surveys (snow pits and snow depth transects, or predefined lines we measure along) where we are able to observe this variability firsthand.

The nature of this landscape forces you to think differently about processes of snow accumulation and loss that don’t get much attention in the literature. I feel that there is a lot of potential for new and impactful discoveries and insights to be uncovered here, with the quantity and quality of data we are collecting in this landscape that composes such a large portion of the Earth’s land surface. Something I have taken away from this field campaign is an appreciation for this type of landscape both in terms of the complexity in processes as well as its natural beauty.

SnowEx researchers Andrew Mullen, Eric Sproles, Caitlin Mitchell, and Ross Palomaki finishing up a snow pit profile. Notice how the snow goes from 3 feet deep to almost nothing over relatively short distances.
SnowEx researchers Andrew Mullen, Eric Sproles, Caitlin Mitchell, and Ross Palomaki finishing up a snow pit profile. Notice how the snow goes from 1 meter (3 feet) deep to almost nothing over relatively short distances. Credit: GEOSWIRL / Montana State University

Guy Brisman White, Undergraduate Student in Earth Sciences, Montana State University

It is a very cool experience to be a part of something that is being used for a larger purpose. As an undergraduate student, I feel that a lot of the work I do is basic and mostly for my own education, so I am happy to contribute to a larger project like SnowEx. Another key experience is learning how data is collected. I have used many different data types throughout my college career, and seeing firsthand how hard it is to record quality data made me appreciate many of the sources I have taken for granted.

Our typical fieldwork days include a long but beautiful drive on often snowy and icy roads. Once we arrive at the site, we have a quick meeting to lay out the fine details of the plan and break into different pairs or groups to complete the tasks. Snow pits were labor-intensive but familiar to me, so I spent the most time working on them. Just a few of the other great learning experiences I had included obtaining weather data from stations, transects, and learning about collecting albedo with drones.

Kendall Wojick, Master’s Student in Land Resource and Environmental Science, Montana State University

Being a part of a NASA research team has been an amazing opportunity to test my fieldwork and teamwork skills in a new setting. I enjoy the responsibility and organization of the data recording set up by NASA. Seeing how they structure their data documentation has improved my personal data housing practices for my graduate studies.

A day in the field for us looking at prairie snowpack is really fun and unique compared to the other mountainous sites in this study. While we don’t get to ski in to our sites, we do get to interact with a beautiful prairie landscape and laugh at how impressive and unexpected the pits we dig are. With the residual berms (flat ridges) of snow that build up near large windbreaks, there are some hefty ice lenses (“bubbles” of ice in rock or soil) from months of melt and freeze patterns that we have to bust through. In order to break through these thick lenses, we even had to employ a “Montana Sharpshooter”, a weighted spade-shaped shovel, that was invented to bust through gravelly concrete-like soils in central Montana. It is always a team effort and a lot of fun to dig and study these pits. I am a soil scientist by trade, so it is an interesting thought experiment to compare how the temporary layers of snow develop compared to the longer-lasting layers of soil. I’ve realized how much snow is truly present on the prairies and what a difference capturing it with wind breaks and stubble can make for dryland agriculture. I feel that the prairies often get overlooked when it comes to snowpack so I am excited that it is included and appreciated in this study.

“This is what happens when you are expecting 75 - 90cm (2.5 - 3 feet) of maximum snow depth, and you get 200 cm (6 feet),” said Eric Sproles, site lead for the Montana SnowEx location and assistant professor of Earth Sciences at Montana State University. SnowEx researcher Zach Miller adjusts his instruments to compensate.
“This is what happens when you are expecting 75 – 90cm (2.5 – 3 feet) of maximum snow depth, and you get 200 cm (6 feet),” said Eric Sproles, site lead for the Montana SnowEx location and assistant professor of Earth Sciences at Montana State University. SnowEx researcher Zach Miller adjusts his instruments to compensate. Credit: GEOSWIRL / Montana State University

After a long day of collecting data – which involves a three-hour drive for us – I love getting to know my research partners better, often playing bluegrass on the drive home with a chance to take in the beautiful Montana landscapes. There is something about a shared passion for these landscapes and the open road that opens people up so we can joke, laugh and discuss everything from silly stuff to deep existential ideas about life and existing on this floating ball of water and rock we call Earth. This NASA project is about as close as I’ll get to being an astronaut, but it does make me think about the incredible progress we have made in remote sensing since NASA was formed in the 1950’s and how it has truly moved forward one small step at a time. Every aspect of a pit we collect seems so small in the moment, but when we repeat that a few hundred times, we have something robust. I can’t wait to see the results of this field season and the accuracy of the SAR sensor, and how this mission moves our collective capabilities forward.

Delta-X Field Stories: Traversing the Marshes

Scientists gather field samples and data from a marsh in coastal Louisiana
Scientists gather field samples and data from a marsh in coastal Louisiana. Credit: Elena Solohin

By Elena Solohin, Florida International University /NEW ORLEANS, LOUISIANA/

My colleague, Emily, and I, with Florida International University’s Wetland Ecosystems Research Lab, kicked off our 2021 field season with a trip to the Mississippi River Delta to conduct research for NASA’s Delta-X project. We met up with a team of scientists from Louisiana State University and spent two weeks conducting fieldwork across the vast salt meadow, cordgrass marshes and freshwater wetlands of Louisiana’s Atchafalaya and Terrebonne Basins.

More specifically, we set out into the marshes by boat to collect soil cores and biomass (organic matter) from below- and above-ground, and to measure marsh elevation. The data we collected will contribute to Delta-X’s main goal – to project future wetland vulnerability along coastal Louisiana under various scenarios of sea level rise and sediment supply using state-of-the-art remote sensing tools, field observations, and modeling approaches across the two basins.

Solohin gathering vegetation samples as part of her field work in coastal Louisiana.
Solohin gathering vegetation samples as part of her field work in coastal Louisiana. Credit: Elena Solohin

Our field work was both exciting and challenging. Our boat rides out to the sampling sites were their own adventures especially with the windy, bumpy, and at times, foggy conditions we encountered. When it was time to get out of the boats, we met our next obstacle – navigating the wetlands, dominated by tall cattail, on foot. Walking through the swampy ground is challenging for even the most experienced wetland scientists!

While trying to keep six feet apart from other teams, we took photographs of the wetland vegetation and recorded water levels. The photographs offered a bird’s eye view of the marsh landscapes and vegetation diversity. While we were working, we also marveled at the blue, over-arching sky, the teeming wildlife around us – including a few sets of beady alligator eyes sticking out of the marsh — and above all, the unique beauty of Louisiana’s coastal wetlands.

Wide view of coastal Louisiana wetlands taken by Delta-X researchers on an overcast day in March.
Wide view of coastal Louisiana wetlands taken by Delta-X researchers on an overcast day in March. Credit: Elena Solohin

After each day of hard work, we were glad to have some time to take a break, even if it was in the same marshy area we’d been working. Now, we’re looking forward to processing the samples we collected to generate the data needed to help understand and predict future wetland vulnerability along coastal Louisiana.

Wide view of coastal Louisiana wetlands taken by Delta-X researchers on an overcast day in March.
Solohin and a colleague relax in the marsh after a hard day of field work.  Credit: Elena Solohin

Delta-X Field Stories: Measuring Water and Sediment in the Delta

Alligator spotted by Delta-X field team in coastal Louisiana.
Alligator spotted by Delta-X field team in coastal Louisiana. Credit: John Mallard

By John Mallard and Tamlin Pavelsky, University of North Carolina /NEW ORLEANS, LOUISIANA/

Cruising through a bayou during recent fieldwork in the Mississippi River Delta, our boat driver casually pointed out an alligator and zoomed on by without slowing. After seeing us scramble to get out our phones to take a picture, though, he realized that perhaps these scientists from the piedmont of North Carolina were a bit less used to seeing alligators than the locals of southern Louisiana, and obliged us by circling back around for some pictures.

This alligator is one of the many species of animals and plants that depend on the unique habitat provided by the bayous, marshes, lakes, and rivers of southern Louisiana. Equally dependent on them are people; we rely on them to protect inland towns from tropical storms, support recreational and commercial fishing, and provide transportation networks for global shipping. With this vital role of the region in mind, DeltaX is measuring how water and sediment move through the delta to learn how and why marshes are changing in the area.

Our team, Tamlin Pavelsky and John Mallard from the University of North Carolina, was in the delta in early March to install sensors that measure water level in the marshes, bayous, and lakes. DeltaX is measuring the water surface elevation and extent via aircraft (NASA’s AirSWOT and UAVSAR), which allow us to get measurements across a very large area. Our sensors provide a check on these airborne measurements at the points where we install them. This process of checking our airborne measurements against points on the “ground” is called “validation,” and is a crucial part of using airborne measurements.

Of course, fieldwork had to be modified due to COVID. Prior to fieldwork the team quarantined at home and then formed a pod for the trip. Instead of flying down and buying groceries on site, we rented a car and packed two coolers full of food for the week. We wore masks at all times when we were outside of our accommodations. We self-monitored for COVID symptoms every day. Although these precautions added some time to our work, we were extraordinarily grateful to UNC and to NASA for helping us figure out how to work safely and successfully!

Tamlin Pavelsky installs water sensor for Delta-X project in coastal Louisiana. Credit: John Mallard

The sensors we installed are pressure transducers. When underwater, they record the pressure of water pushing on a membrane inside the sensor, and then we use that weight to determine the depth of water above them. The sensors are only about the size of a cigar, but they can record tens of thousands of measurements without running out of battery. The sensors we installed in March will stay in the field through Fall, when we’ll return to retrieve them and download the data.

Our work was done from a small motorboat whose flat hull was specially designed to work in shallow water. On a typical day we would meet our hired boat driver at a local boat ramp to put the boat in the water just after breakfast and be back at the boat ramp by 3 p.m. after installing 5-9 sensors. On board, we had about a dozen 10’ lengths of PVC taking up a whole side of the boat, along with our sensors, tools, and food and snacks for the day.

Caption: John Mallard pushing PVC pipe into the mud to install a sensor for the Delta-X project.
John Mallard pushing PVC pipe into the mud to install a sensor for the Delta-X project. Credit: Tamlin Pavelsky

We would navigate to pre-determined locations to install sensors, which were usually on the edge of the water, and the driver would gently run the bow aground to keep us in place. Then we pushed a PVC pipe into the mud as far as we could by hand and finished the job with the post pounder.

We needed to get them deep enough into the mud so that a slit cut in the side of PVC was below the water line and would allow water into the pipe. We tied the sensor to the cap of the pipe using Kevlar cord that is highly resistant to wear, and hung it inside the pipe so that it was below the water surface. At each location we took measurements of the height of the pipe, the length of the cord, and depth of the water so that we could later translate the depth of water measured above the sensor to the actual depth of water at that point. After installing the sensor, we marked the location with a handheld GPS device and moved on to the next site.

On some days we only traveled a few miles and had to take the boat out of the water multiple times to drive to different boat ramps, but on our last day we put in at a single ramp and traveled more than 70 miles across the lakes and bayous of Terrebonne Bay. The weather was sunny, low 70s, and we had lunch on a narrow beach by an inlet separating the Gulf of Mexico from the bay. We watched birds and dolphins fishing for their own lunch of small fish and crustaceans in the inlet. It was a wonderful break at the end of a successful field trip. After a challenging year with so many disruptions of our work, among so many other things, it was such a relief to feel like we’re starting to be able to “get back to work”!

Delta-X Field Stories: Collecting “Marsh Popsicles”

 

LSU team (Andre, Brandon, Amanda) measuring accretion at their feldspar marker horizon station in coastal Louisiana for NASA’s Delta-X
LSU team (Andre, Brandon, Amanda) measuring accretion at their feldspar marker horizon station in coastal Louisiana for NASA’s Delta-X. Credit: Amanda Fontenot

By Amanda Fontenot, Louisiana State University /NEW ORLEANS, LOUISIANA/

Although most of my work happens in the lab, office, or home, field days are some of the most important days of the year for my research. “Going to the field” is when we get to physically visit the wetlands that we spend so much of our time describing, researching, and caring about. Field days can require a lot of effort and time to execute, but they can also be a beautiful time to get out of the office and even have some fun with our colleagues.

I am a graduate student at Louisiana State University (LSU), and I am working towards my Masters of Science in Coastal and Ecological Engineering. I work with Dr. Robert Twilley in the Coastal Systems Ecology Lab at LSU, and my thesis research falls under NASA’s Delta-X Project. In October 2019, Dr. Andre Rovai and I laid a total of sixty-nine feldspar marker horizons at our seven Delta-X field sites in order to measure short-term sediment accretion. This March we traveled back to our markers in the Atchafalaya and Terrebonne basins of coastal Louisiana to measure this accretion.

We made these “markers” by pouring custer feldspar (a fine, white, mineral powder used in ceramics) on top of the soil surface. We use this material because it stays intact and provides a clear indication of when the experiment started. Over time, a soil layer forms on top of the white marker from both plant production and material that is deposited from rivers and the Gulf of Mexico. After placing the marker, our team comes back every 6 months and measures how thick that newly formed soil layer is on top of our marker. We then can divide that number by how many days it has been since we laid the marker, and we end up with a short-term sediment accretion rate. This rate is important in understanding how these wetlands will compete with increasing sea levels and local subsidence that threatens a majority of Louisiana’s coastal wetlands.

Most field days start pretty early in the morning, and this campaign was no exception. Our LSU team (Dr. Andre Rovai, Brandon Wolff, and I) left campus around 4:30 a.m. and headed to the boat launch to put our boat in the water. Since these sites are pretty mucky and we need to be careful to not step on our markers, we also travel with an airboat and our handy dandy airboat operator, Cade. After the boats are in the water, we drive to our sites and get to enjoy a nice sunrise on the water.

Depending on the morning, we usually get to our site around 9:00 or 10:00am and huddle up for a game plan. For this campaign, we needed to complete four tasks at each site: 1) measure accretion on top of our feldspar markers, 2) collect 50cm deep soil cores that help characterize the site, 3) deploy two water level recorders that collect data every 15mins, and 4) measure marsh elevation at varying points using our RTK instrument, which uses satellite-based positioning systems like GPS to estimate the elevation of a point. In the morning, we usually discuss in what order we might finish these tasks and who is in charge of each part of the process.

Most days, I am the one measuring and recording our accretion numbers for the feldspar markers. In order to minimize how much we disturb the soil around and within our feldspar marker, we use what’s called a “cryo-coring” technique – which we have affectionally named collecting “marsh popsicles.” In the field, we push a long, skinny copper pipe into the soil where we previously laid our marker and pump liquid nitrogen into the pipe. Since the liquid nitrogen gets so cold, some of the soil freezes around the pipe and ‘Voilà!’ we pull up our “marsh popsicle.”

“Marsh popsicle” with white feldspar marker ring. We measure the distance from the top of the popsicle to the beginning of the white marker.
“Marsh popsicle” with white feldspar marker ring. We measure the distance from the top of the popsicle to the beginning of the white marker. Credit: Amanda Fontenot

On our popsicles, we see our feldspar marker as a white ring around the muddy popsicle. I measure the distance from the top of our popsicle (marsh surface) to that white ring (feldspar marker) with calipers and record it in my field notebook to look at later. Usually by the time we collect all the popsicles we need at the site, we go collect our soil cores and then are ready to eat lunch. We bring our own lunch to enjoy but what’s almost guaranteed is a plethora of light blue Gatorade and Andre’s signature glass bottle of Coke.

After lunch, we continue working on the other tasks for a few hours and try to help out the other field team from Florida International University (FIU) if we finish up before them. When we all finish up our field tasks, we start the long journey home. We pack up our supplies, put samples on ice, change clothes if we got too messy or wet in the field – those boat rides can get really chilly otherwise — and drive the boats back to the launch. At the launch, we get the boats back on the trailer and drive back to LSU, arriving later in the evening.

LSU team (Andre, Brandon, and Amanda) in foreground at their feldspar station with the FIU team (Edward, Elena, and Emily) in background.
LSU team (Andre, Brandon, and Amanda) in foreground at their feldspar station with the FIU team (Edward, Elena, and Emily) in background. Caption: Amanda Fontenot

Depending on the weather, we might go out to another site the next day, meaning a meeting time of 4:30 a.m. back at the school. After we finish at campus, I race home to shower, eat dinner if we haven’t stopped somewhere on the drive back to Baton Rouge, clean my field clothes, and jump in bed to do it all over again the next day. Each team member plays an important role in the field, whether that be holding open bags to store samples, operating our liquid nitrogen tanks, or making sure everyone stays hydrated while we work. Although field days can be quite tiring and stressful, the work that our team accomplishes not only works towards the goals of the Delta-X project but increases the general knowledge of Louisiana’s coastal wetlands and the ecosystem services they provide.

Lightspeed: A Marvelous Method for Measuring Mountain Snow

By Dan McGrath and Randall Bonnell, Colorado State University /CAMERON PASS, COLORADO/

The word lightspeed conjures different images for different people. Star Wars fans may connect lightspeed to the Millennium Falcon, while radar scientists may think of the velocity of electromagnetic energy. Radio waves, a form of electromagnetic energy, travel at “lightspeed” through a vacuum, but when they encounter snow, they slow down drastically.  Sounds bad, right?  It might be if you’re trying to get somewhere fast, but if you’re trying to measure the amount of snow on the ground, it’s just what you’re looking for.

The field site at Cameron Pass, Colorado.
The field site at Cameron Pass, Colorado. Image courtesy of Lucas Zeller.

Over the past four months, our team from Colorado State University, along with teams across the western United States, has been tramping around in the snow each week trying to figure out just how much those radio waves might be slowing down. Why? In 2021, the NASA SnowEx campaign is focused on testing the use of airborne L-band Interferometric Synthetic Aperture Radar (InSAR). In this method, an instrument aboard a plane sends out radio waves to measure changes in snow-water equivalent (SWE) – or the amount of water stored in the snowpack – down below. The basic premise of this approach is that as more and more snow accumulates on the ground, it takes a radar wave longer and longer to travel from the aircraft, through the snow to the ground, and back to the aircraft. Each week, the NASA Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) team flies a plane overhead to collect InSAR observations of the snowpack. Meanwhile, we collect ground observations to document changes in snow depth, SWE, and other characteristics of the snow to help evaluate InSAR as a way of measuring SWE.

There are a lot of different ways to measure snow on the ground. You can probe it to measure its thickness or temperature, you can dig through it to measure its mass and density, and you can employ all kinds of fancy equipment to measure things like the surface area of grains of snow, or spectral reflectance. But trying to determine any of these details on a global scale from instruments in space becomes much more difficult.  Even a fundamental question, like how much SWE is in a basin, can be difficult to answer.

Radio waves might be one answer to this difficult question. As radio waves travel through the snowpack, their velocity depends on the density of the snow. For example, denser snow means the radio waves will move more slowly. If we can measure the travel time (or phase, more on that later) of those radio waves very precisely, we can calculate SWE accurately. For these reasons, the SnowEx21 campaign is an exciting campaign – but what makes it even more important is its applicability. In 2022, NASA and Indian Space Research Organization (ISRO) will launch NISAR, a space based InSAR mission. It will carry a L-band (1-2 GHz frequency) radar instrument, meaning that those slow radar waves we’re evaluating from UAVSAR will soon be making the trip from space!

Two scientists trek through the snow to a site in Cameron Pass, Colorado.
Randall Bonnell (left), PhD student at Colorado State University, and Lucas Zeller (right), Master’s student at Colorado State University, pull the GPR sled at Cameron Pass, Colorado. Credit: Alex Olsen Mikitowicz

During the SnowEx21 Campaign, our team has been making weekly trips to Cameron Pass, a site at about 10,000-foot elevation about two hours west of Fort Collins, Colorado.  One of the key observations we made each week was repeat ground-penetrating radar (GPR) surveys along multi-kilometer transects. GPR works by transmitting a radar pulse into the snow and measuring the two-way travel time and strength of the returning signal to produce a radargram. These surveys are particularly valuable for evaluating UAVSAR, as there is significant overlap between the methods.

We dig snow pits and measure the density of the snowpack to determine a velocity for converting the GPR-measured travel time to depth and SWE. By taking repeat measurements in the same areas week after week, we can measure a change in travel time, snow depth, and SWE between each interval, thereby providing a direct comparison to what UAVSAR is measuring. UAVSAR and other InSAR-based approaches measure changes in phase (a portion of an electromagnetic wave) between two subsequent radar acquisitions. This change in phase, on par with the change in travel time for our GPR instrument, is the key to detecting changes in SWE. However, phase changes are inherently complex and there is still much to discover regarding their interpretation. That is where other ground observations come into play.

A radargram showing the snow surface and the ground surface.
Example of a processed radargram collected at Cameron Pass, Colorado. The red line highlights the picked ground surface, comprising the soil, rocks, and vegetation that the snow sits on. The top of the radargram is the snow surface. Credit: Randall Bonnell

Each week, we dug snow pits at two different sites to measure density, stratigraphy, and temperature of the snowpack. Density measurements are used to estimate a radar velocity for calculating snow depth and SWE from GPR travel times. Stratigraphy observations identify layers in the snowpack, which may influence InSAR or GPR observations. Temperature (and its corresponding gradient within the snowpack) is used to understand how snow crystals are changing and for identifying the presence of liquid water, as water strongly influences radar velocity. Additionally, understanding soil conditions – like whether the ground is frozen or thawed – and ground cover such as vegetation is key to interpreting InSAR observations. Outside of the pit, we also measured snow depths using a GPS-equipped probe, providing an additional approach to measure the change in SWE between each UAVSAR flight.

A scientist shows off a sample of a snow pit to measure snow density.
Ella Bump, Master’s student at Colorado State University, takes a sample of snow from the snow pit to measure density. Credit: Alex Olsen-Mikitowicz

While intergalactic space travel is still science fiction, the use of radar to measure our global snow resources from space is becoming a reality. The SnowEx21 campaign is providing a critical link between theory and practice and, after a good deal of data analysis, it will undoubtedly leave a refined view of the capabilities and limitations of L-band InSAR for measuring changes in SWE. Such progress is necessary, as snow is a critical and highly valued resource relied on by billions of individuals around the world.  Climate change is directly impacting this resource in a multitude of ways, including a reduction in the length of the snow-covered season and the total amount of snow that accumulates, and the impacts are predicted to become much more severe by mid-century. As such, the need for accurate, global estimates of SWE has never been more urgent. While SnowEx21 is only one small part of the puzzle, we’re hopeful that the progress made during this campaign will contribute to realizing this goal.

CAMP2Ex Team Mourns Passing of Senior Climate Researcher

Gemma Narisma boarding NASA’s P-3 research aircraft during the 2019 CAMP2Ex deployment in the Phillipines. Credit: NASA
Gemma Narisma with NASA’s P-3 research aircraft during the 2019 CAMP2Ex deployment in the Phillipines. Credit: NASA

By Katy Mersmann, NASA

We’re so saddened by the loss of our teammate Dr. Gemma Teresa Narisma. She was a passionate climate researcher and the Philippine lead for the Cloud, Aerosol, and Monsoon Processes Philippines Experiment (CAMP2Ex).

As the director of the Manila Observatory and a professor at Ateneo de Manila University, she not only helped plan the research, but she aggressively brought students into the CAMP2Ex project, helping lead the next generation of meteorologists and climate researchers in forecasting weather for flights and data collection.

“We witnessed brightness, peace, curiosity, joy, courage and determination,” Simone Tanelli of NASA’s Jet Propulsion Laboratory said, in Gemma’s remembrance. “And Gemma was right at the center of that, emanating them, and the whole Manila Observatory team shone with them.”

Gemma’s expertise was internationally recognized: She served as an author on the Intergovernmental Panel on Climate Change’s (IPCC) Sixth Assessment Report and received numerous awards honoring her work as a researcher. Gemma was one of the leading subject matter experts in the Philippines on climate resilience, severe weather and natural hazards.  She was consulted at every level of the Philippine government.

Gemma was a dedicated and enthusiastic teammate and mentor; a role model for younger scientists and a friend to all who met her. Her smile lit up a hangar, and it was a joy to watch her celebrate as her students took their first science flights with CAMP2Ex.

“The world has lost a valuable scientist, and the Philippines has lost an environmental spokeswoman, but we have lost a beloved friend” said Jeffrey Reid, U. S. Naval Research Laboratory.

SnowEx Scientist Finds her Love of Snow Science on the Slopes

This dynamic environment of snow cover and texture outside of Cooke City, Montana, January 2021 is also a water reservoir for nearby communities.
This dynamic environment of snow cover and texture outside of Cooke City, Montana, January 2021 is also a water reservoir for nearby communities. Credit: G. Antonioli

By Gabrielle Antonioli, Montana State University /BOISE, IDAHO/

Being a snow scientist is an interesting career. Growing up in a small town in Montana, I was immersed in snow. But I saw it as one set thing—a blanket, unmoving, a cold, white mass. Only far later in life did I learn what a changing and integral role snow plays in our day-to-day life.  Snow drives the winter economies of most Western states, acts as water reservoirs for those same regions and far beyond and is a fundamental part of life—whether we see it fall on our city streets or not.

I wasn’t always interested in studying snow, though. I received my bachelor’s degree in organismal biology, aimed at a career in medicine.  A fundamental switch flipped in my brain as I worked in mountain environments, found snow science and ski mountaineering mentors, and realized that snow could be as changing and complex as any living organism. Mitigating risk and hazard while skiing – alongside trying to understand the evolution of a snowpack in a given mountain range – evolved into an encompassing and engaging mental and physical process for me. It is from this divergence in thought and passion that I found my path to the Earth sciences while skiing, teaching avalanche education, and backcountry ski-guiding. I am now completing a master’s in Earth sciences, focusing on snow science, at Montana State University. Amidst finishing this degree remotely due to the COVID-19 pandemic, I chose to move to Idaho and test my skills in a different environment. I am now working as a research technician for the NASA SnowEx project based in Boise, Idaho.

The author and another research assistant, Megan Mason, identify snow crystal types in an early-season snow pit at Copper Mountain, Idaho, December 2020. Credit: G. Antonioli
The author and another research assistant, Megan Mason, identify snow crystal types in an early-season snow pit at Copper Mountain, Idaho, December 2020.
Credit: G. Antonioli

SnowEx is a multi-year NASA campaign to study snow using remote sensing.  This involves things like radar, remote-controlled aircraft (UAVs), light detection and ranging (LiDAR), and more. This research is designed to inform plans for a future NASA satellite that would study snow from space. The primary instrument we’re using this year is Inteferometric Synthetic Aperture Radar (InSAR). InSAR flies over the Boise site each week, as well as other sites located near more distant mountain ranges, and uses radar to estimate the depth of the snow. We compare the measurements over time as InSAR continues its weekly flights over this site. The change in snow depth is directly related to the change in how much water is stored in the snowpack, which scientists call snow water equivalent (SWE). This is particularly important in mountain ranges that supply water to urban areas.

Even the most precise remote sensing instruments need to be validated with actual snow data collected in the field. For this reason, the field teams of technicians set out to various study plots across the Western U.S. each week to dig snow pits, identify the structure of the snowpack, measure density and liquid water content, and track each new snowfall.  We travel on snowshoe, ski, or snowmobile.  The teams I am on visit sites using backcountry skis with removable sticky skins and a special binding that rotates to either free the heel of a ski boot or lock it in place, designed for both uphill and downhill travel.

SnowEx scientists trek to the study site on cross-country skis. Credit: G. Antonioli
SnowEx scientists trek to the study site on cross-country skis. Credit: G. Antonioli

A shallow early-season snowpack at Banner Summit, Idaho in December 2020 with several layers of melting and freezing visibly preserved. Credit: G. Antonioli
A shallow early-season snowpack at Banner Summit, Idaho in December 2020 with several layers of melting and freezing visibly preserved.
Credit: G. Antonioli

For our first field campaign mid-January, our team drove a winding highway to reach a mountain trailhead far outside of Boise known as Banner Summit, the upper reaches of which source water for rivers and groundwater that Boise locals utilize. We loaded our packs with science gear and used skis to reach the Banner Summit research site. In addition to the density scales and SWE measuring devices we bring, each site has stationary equipment in place to measure a bevy of meteorological variables—like new snowfall, SWE, total depth of snow, and wind speed.  The depth and SWE measured by these set stations is also compared to the InSAR estimates, in addition to our on-the-ground measurements.

(L): Scientists dig these horizontal columns to sample the density in different parts of a snowpack. Each box represents a density sample taken every 10 cm. Multiple density cores of each layer are taken horizontally to account for any anomalies and for accuracy. (R): Measuring a later season snowpack stacking up outside of Boise, Idaho in January 2021. Credit: G. Antonioli
(L): Scientists dig these horizontal columns to sample the density in different parts of a snowpack. Each box represents a density sample taken every 10 cm. Multiple density cores of each layer are taken horizontally to account for any anomalies and for accuracy.
(R): Measuring a later season snowpack stacking up outside of Boise, Idaho in January 2021.
Credit: G. Antonioli

So, why is so much time and effort being devoted to finding a better way to monitor snow cover if we have things like snow telemetry stations (we call them SNOTELs) and stream gauges already in place to monitor snowfall and subsequent runoff? The answer is that there are disparities in weather patterns, rising rain lines (or the elevation at which rain is cold enough to turn to snow) in the mountains, and the ever-changing climate that is at our doorstep.  For my master’s thesis, I measured variability in snowfall amounts on different types of terrain and during various storms Hyalite Canyon, Montana. I ski in this canyon often and know that the upper elevation SNOTEL under-reports snowfall amounts by about half—not due to instrumentation error, but due to the location of the station as well as the terrain surrounding it. Not only is this a common problem, but disparities like this make a huge difference for avalanche and hydrologic forecasters alike. I am hopeful that in the future, fusing different technologies like those in use for SnowEx, along with validation from on-the-ground data like my snow pits, will alleviate these issues and help locations that rely on snow melt for water more accurately monitor and plan for the future.

HP Marshall and Mitch Creelman enjoying some post-work field time.
HP Marshall and Mitch Creelman enjoying some post-work field time.
Credit: G. Antonioli

ACTIVATE Begins Year Two of Marine Cloud Study

NASA’s ACTIVATE mission recently began its second year of flights. Here, final preparations are being made to the HU-25 Falcon prior to a flight.
Credits: NASA/David C. Bowman

By Joe Atkinson / NASA’S LANGLEY RESEARCH CENTER, HAMPTON, VIRGINIA/

A NASA airborne study has returned to the field for a second year of science flights to advance the accuracy of short- and long-term climate models.

The Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) began the third of six planned flight campaigns — two campaigns each year beginning in 2020 and ending in 2022 — in late January at NASA’s Langley Research Center in Hampton, Virginia.

Cloud formation in the atmosphere depends on the presence of tiny particles called aerosols. ACTIVATE scientists are working to understand how variations in these particles from human and natural sources affect low lying clouds over the ocean and how those clouds in turn affect the removal of these particles from the atmosphere.

Read more on nasa.gov

Pandemic Delays, But Doesn’t Slow, Ice Melt Research in Greenland

A bit of snow fell before the DC-3 plane took off for another day of dropping probes into the waters around Greenland. Credit: Josh Willis/JPL

By Lara Streiff

Despite racing against impending harsh weather conditions, a red and white World War II aircraft flew slowly and steadily over the icy waters surrounding Greenland in August and September. Three weeks delayed by pandemic restrictions, scientists from NASA’s Jet Propulsion Laboratory inside this retrofitted DC-3 plane started dropping hundreds of probes as part of an annual expedition known as the Oceans Melting Greenland (OMG) Project.

Since 2016, the OMG project has conducted numerous flights over the waters near Greenland’s lengthy and jagged coastline. They drop roughly 250 probes each year (though they managed a record 346 during this extraordinary 2020 expedition) which then relay temperature and salinity data. The team uses this information to help determine how much the surrounding ocean is contributing to Greenland’s ice melt.

“The glaciers are reacting very strongly to the ocean and we ignore that at our peril,” said JPL scientist and principal investigator Josh Willis. “The oceans have the potential to melt the ice very quickly and drive the sea level rise even higher than we expected.”

If it all melted, Greenland’s ice could contribute as much as 25 feet of sea level rise—though Willis assures us that this is not expected within the next year, or even the next 100 years. The big question that his team is trying to help answer is rather the speed at which the ice is melting.

In the northwest of Greenland, where the Upernavik glacier meets the Atlantic. Credit: Josh Willis/JPL

Unlike icebergs—which float in water—glaciers sit atop a land mass, seemingly exposed and vulnerable to the warming atmosphere. While the atmosphere is a significant factor, it is not solely responsible for glacial melt. As the glaciers in Greenland start to ooze off the island in massive rivers of ice, they carve fjords into the landscape until they finally connect with the sea. While surface waters are generally frigid, the warmer ocean waters from below can cause the glacier to melt more quickly and speed up the amount of ice that drains off the land into the ocean.

Though the coronavirus pandemic had sweeping impacts across the globe, it didn’t halt environmental processes like Greenland’s glacial ice melt. It also didn’t impede the resolve of the OMG scientists to continue their work.

Starting in March up until the day they landed in Greenland on August 24, Willis says he wasn’t sure they would be able to collect their data this year. But cooperation between the various stakeholders, including NASA, the State Department, and the governments of Canada and Greenland, was key. Willis also gives credit to a huge amount of hard work by OMG’s Project Manager, Ian McCubbin of JPL, for making it possible. “If it wasn’t for McCubbin,” said Willis, “we’d still be sitting on our couches.”

Coordinating the scientists and equipment necessary for any expedition requires a great deal of planning, and the additional pandemic-related precautions made everything just a little bit more complicated.

“It was like a whole new layer, after you go across the border and go through customs and boarder control, now you also go through coronavirus screening,” Willis said.

Oceans Melting Greenland lead scientist Josh Willis getting tested for COVID-19 while in Greenland. Credit: Josh Willis/JPL

In addition to getting tested a whopping seven times, two of which took place before even stepping foot in Greenland, Willis and the other members of the OMG team were very cautious. There was an initial isolation period after landing on the island during which they could fortunately work on the plane and equipment preparation, wearing masks when traveling to and from the site and no contact with locals. Greenland has had very few cases of COVID, and doesn’t have enough hospitals to handle any outbreaks, so the team was especially conscious of limiting their interactions with people there.

One exception was communicating with the nurses conducting their COVID-19 tests. “It was quite an experience getting tested this many times,” said Willis, “but the most fun was actually with nurses in Greenland, who were very nice and asked about our mission, so we got to tell them about what OMG was doing—and I suspect they followed along the rest of our journey on social media.”

Though some legs of the scientists’ expedition were delayed or more challenging as a result, Willis says it was well worth the extra effort to ensure everyone’s safety.

The outcome turned out to be a banner year for the project, despite the late start. Instead of heading north at the beginning of the month, it was already well into August when Project Manager Ian McCubbin and the three scientists from JPL—Ian Fenty, Mike Wood, and Willis himself—were able to meet with their flight crew from Kenn Borek Air.

The crew after their successful season. In the photo from left to right: Josh Willis, OMG lead scientist; Mike Wood, OMG scientist; Linden Hoover, Kenn Borek co-pilot; Jim Haffey, Kenn Borek pilot; and Ian Fenty, OMG scientist. Not pictured are Gerald Cirtwell, Kenn Borek flight engineer, and Ian McCubbin, OMG project manager. Credit: Josh Willis/JPL
The crew after their successful season. In the photo from left to right: Josh Willis, OMG lead scientist; Mike Wood, OMG scientist; Linden Hoover, Kenn Borek co-pilot; Jim Haffey, Kenn Borek pilot; and Ian Fenty, OMG scientist. Not pictured are Gerald Cirtwell, Kenn Borek flight engineer, and Ian McCubbin, OMG project manager. Credit: Josh Willis/JPL

Once they were on the ground in Greenland, their main concern was for the conditions they might encounter once back in the air.

“Weather starts to get pretty rough in September, and very rough in October.” said Willis. Fortunately, they were able wrap up their surveys by mid-September, mostly dodging the snow, sleet and wind that might impede their ability to drop all of the probes. “It was a sprint to the finish line, but we were able to accomplish everything we wanted to do and more.”

In fact, the team encountered unusually good conditions in the north east parts of the island, where ice and fog usually prevent access. As a result, they measured some glaciers that had never been sampled before.

When the project first began in 2016, the scientists also flew a jet with a radar strapped on the bottom to measure big swaths of glaciers from above, but NASA’s ICESat-2, an Earth-observing satellite that measures the mass of ice sheets and glaciers down to the inch that launched in 2018, takes care of that part of the mission now.

More than 45 scientific papers have now been published based on OMG data, with several more in progress. Willis says that every new discovery reminds them that the oceans are more important than they ever thought possible.

This year they noted new observations of Greenland’s largest glacier Jakobshavn, which has been closely monitored since the start of the project in 2016. In the first couple of years, the water near Jakobshavn cooled by 2.7 degrees Fahrenheit (1.5 degrees C)—a whole lot for a block of ice according to Willis. That cooling slowed the melting of the glacier, which then started growing instead. But early this year warm water returned to Jakobshavn and the recent observations suggest it is now thinning once again.

The view of Greenland’s Jakobshavn glacier from the DC-3 plane which carries the Oceans Melting Greenland Project scientists Credit: Josh Willis/JPL
The view of Greenland’s Jakobshavn glacier from the DC-3 plane which carries the Oceans Melting Greenland Project scientists. Credit: Josh Willis/JPL

These continued discoveries from the project are very exciting for the scientists and organizations involved. Because of this, the OMG project has gotten approval to continue its research beyond the original end date, meaning that Willis and his crew will again be making their way back to Greenland next August, and this time hopefully without much delay.

ACTIVATE Makes a Careful Return to Flight

Masks are part of the safety protocol for ACTIVATE scientists. Here, Yonghoon Choi prepares for a science flight on the HU-25 Falcon. Credits: NASA/David C. Bowman

By Joe Atkinson / NASA’s Langley Research Center, Hampton, Virginia/

Four months ago, with COVID-19 disrupting life across the globe, it seemed virtually unthinkable that a major NASA airborne science campaign would fly again anytime soon.

But today, that’s exactly what’s happening.

In August, NASA’s Aerosol Cloud Meteorology Interactions Over the Western Atlantic Experiment (ACTIVATE) eased into its second set of 2020 science flights out of NASA’s Langley Research Center in Hampton, Virginia. Barring any threats to the health or safety of the researchers or crew, flights will continue through the end of September.

Those flights are taking scientists over the western Atlantic Ocean to study how atmospheric aerosols and meteorological processes affect cloud properties. In addition, modelers will use data from these flights to better characterize how the clouds themselves, in turn, affect aerosol particle properties and the amount of time they spend in the atmosphere, as well as the meteorological environment. Coordinated flights between a King Air and an HU-25 Falcon allow researchers to fly above, below and through the clouds with a suite of instruments that can take measurements remotely, or from the air around the aircraft.

The HU-25 Falcon sits on the tarmac just ahead of a flight. Credits: NASA/David C. Bowman

“The data have been really good so far,” Armin Sorooshian, ACTIVATE principal investigator and an atmospheric scientist at the University of Arizona, said of the summer flights. “We’ve seen some interesting features, like smoke from the wildfires on the West Coast.”

That smoke can seed clouds over the Atlantic Ocean.

Sorooshian is leading the campaign remotely from his home in Tucson, Arizona, where he and his wife are juggling work and the care of two children — a two-year-old boy and a baby girl who was born in July.

He admits it’s “a little tough.” But in a world where these flights could have been scrubbed from the calendar completely, Sorooshian isn’t interested in dwelling on the negatives.

“They’re good problems,” he said.

Good Problems

The ACTIVATE team began the first of two planned 2020 flight campaigns in February. They completed most of those flights, but had to pull the plug a little early in mid-March when concerns about the spread of COVID-19 began to sweep across the U.S. At that point, the fate of the second set of flights, originally scheduled for May and June, was — pardon the pun — very much up in the air.

As the COVID situation evolved, though, and as Langley leadership began to admit a limited number of research projects back on center with stringent safety protocols in place, it became clear there might be a glimmer of hope for ACTIVATE.

ACTIVATE is uniquely positioned among other current NASA airborne science missions because it’s based out of a NASA center, and the flight crew and many members of the science team are also based out of that center. John Hair, ACTIVATE project scientist with Langley’s Science Directorate, knew that from a purely logistical perspective, the mission could return to flight without the need for anyone to travel in from out of town.

“We had an opportunity because ACTIVATE has a relatively small crew that can operate the instruments in the aircraft, and do that, we felt, safely — albeit with some changes to the initial plans we set out,” he said.

Besides obvious stuff such as wearing masks and being mindful of social distancing, those changes include conducting the various daily flight planning meetings and pre-flight briefings completely via video conference. Researchers are also doing real-time monitoring of flight data from their homes. For researchers who are flying or need to be on center, the project has found ways to streamline some processes.

“For example, people are learning how to do their calibrations at the end of the flight after the instruments are already warmed up,” said Hair. “And then it only takes an hour to do.”

Compare that to the three or four hours it can take a researcher to warm up and calibrate an instrument before a flight.

The King Air rolls out of the hangar before a science flight. Credits: NASA/David C. Bowman

The entire operation has taken a lot of careful planning and coordination between Langley’s Science Directorate, Research Services Directorate and Center Operations Directorate. Sheer determination has certainly played a role as well.

“We all signed up for supporting research as it comes in. ACTIVATE was in the middle of a major campaign and we wanted to get them back to flying as soon as we could,” said Taylor Thorson, ACTIVATE project pilot with Langley’s Research Services Directorate.

Sorooshian believes this experience could be instructive for the next round of flights, which are currently scheduled to kick off in February 2021 when COVID-19 could still be a significant concern.

It’s not just instructive from a safety perspective. Marine clouds are more scattered and difficult to forecast in the summer.

“Flying this summer also allows the team to hone the flight planning strategies, which can build upon heading into the next two years of flight campaigns,” he said.

For now, he and Hair are just happy to see a study they both care deeply about back in action.

“This is exciting that we’re out doing some flights,” said Hair. “People are excited to get the critical science data that we’re collecting on these flights.”

The ACTIVATE science team includes researchers from NASA, the National Institute of Aerospace, universities, Brookhaven National Laboratory, Pacific Northwest National Laboratory, the National Center for Atmospheric Research and the German Aerospace Center. The current flight campaign is the second of two in 2020, with two more to follow in 2021, and another two in 2022.

ACTIVATE is one of five new NASA Earth Venture campaigns originally scheduled to take to the field in 2020. Three of the five have been postponed due to COVID-19. To learn more about the other campaigns, visit: https://www.nasa.gov/feature/goddard/2019/nasa-embarks-on-us-cross-country-expeditions