By Audrey Delpech, postdoc in the Atmospheric and Oceanic Sciences department at UCLA
Being part of the NASA S-MODE oceanographic mission was a great experience for me. It was only my second oceanographic mission and my first one on a US research vessel. I learned a lot about how to use the different instruments, interpret their data and about the complexity of the ocean.
This mission is designed to study submesoscale fronts – which correspond to abrupt changes of water temperature or salinity over scales of about 6 miles or 10 kilometers in the ocean. They act in a similar way as we have fronts in the atmosphere that bring us cold or warm weather, rain or dry air masses. S-MODE is making the first observations that show such fronts do play a role in stabilizing our climate by acting as a connector between the deep ocean and the atmosphere, and controlling the exchanges of quantities such as heat or carbon.
Because these fronts move and change throughout the day, we didn’t have a set sampling plan. Instead, we would look at the real-time conditions so we could figure out where to go and how to get the best measurements from the ship and three aircrafts. This is called “adaptative sampling.”
My research has lately evolved towards understanding how the ocean interacts with the atmosphere above. I have been working with models to simulate and study how submesoscale ocean motions interact and exchange energy with the winds. Onboard the ship I worked with an instrument called a radiosonde. Radiosondes are sensors which are attached to a balloon and measure temperature, humidity, wind speed and direction as they rise up in the air. I’m interested in seeing how the temperature of the ocean across these fronts influences the wind speed of the air above. We released radiosondes at regular time intervals as the ship was moving across fronts. These measurements will hopefully confirm the findings from the numerical models, and I am really looking forward to analyze them.
Another important part of my work onboard was to provide real-time weather conditions from the ship. The onshore team used my reports every day to make the decision of whether to fly the aircraft or not, or if they needed to adapt their survey region. Some airborne instruments required clear-sky conditions or high enough clouds so they could fly in the clear underneath. The radiosondes measurements helped me figure out how high and how thick the clouds were, two important parameters to characterize the cloud coverage.
I also collected radiosondes’ atmospheric temperature and humidity profiles from the sea surface to about 8 km height at the same time the airplanes were flying overhead. These data will help calibrate the airborne infrared remote sensors.
Besides the weather reports, I also took part in many other operations. One was helping to deploy an instrument called a CTD (for Conductivity, Temperature and Depth). This instrument measures the temperature and salinity of the sweater as a function of depth as the ship is moving across the ocean. This helped us understand the vertical extension of the front in the subsurface ocean (from 0 to about 200m deep). I also helped filter water samples for future onshore DNA analyses, which will give a sense of the diversity of microscopic phytoplankton across submesoscale fronts, deployed and recovered Lagrangian floats, which are designed to drift with currents, helped navigate the ship to chase fronts, and helped with the real-time processing of data.
This experience has taught me a lot about the challenges of “adaptative sampling” and made me think differently about the value of the data collected. I now know the amount of coordination and labor that are behind them.
It was also a wonderful human experience. The community of people we were forming on this cruise was very diverse, with everyone coming from a different horizon. Several nationalities were represented and each person I met has brightened up my experience at sea. I have made some really good friends and met wonderful scientists I am looking forward to collaborate with in the future.
A low, surging wind picks up as the first few raindrops splatter onto dusty ground. Dense cumulonimbus clouds, like soot-stained cotton balls, knot tighter and tighter in the sky. While the thick scent of petrichor and ozone invades the air, an electric burst of lightning slashes through the sky; deafening cracks of thunder follow, like the footsteps of some celestial giant crashing through the atmosphere.
Summer thunderstorms like this may last just a few minutes, or for several hours. In their wake, the NASA Dynamics and Chemistry of the Summer Stratosphere, or DCOTSS, operations room buzzes with activity. After a storm, the Kansas-based crew sends out a high-altitude plane loaded with instruments to take measurements and make observations.
In a process called convection, thunderstorms’ roiling activity draws up warm air from the lower atmosphere and cools it as it travels higher, sometimes shooting it into the next atmospheric layer above called the stratosphere. The DCTOSS team aims to figure out exactly what material swirling in the air gets transferred between atmospheric layers when this happens.
“Until this mission, nobody had ever tried to do this,” said Ken Bowman, DCOTSS principal investigator. “There haven’t been direct observations to tell us how this happens or how important it is.” Bowman and his crew completed their final fight in July, and are now back at in the lab to begin sorting through the data they’ve collected.
For the last two summers, DCOTSS team meteorologists kept their eyes peeled for thunderstorms in North America, which is a global hotspot for thunderstorms that overshoot air into the stratosphere. When a storm erupted, the team had to estimate if and where the storm’s plume would overshoot and air at the top of the storm would mix with stratospheric air, called the storm’s outflow. While the meteorologists used radars and satellites to direct the pilot of NASA’s high altitude Earth Research or ER-2 aircraft to the storm outflow, scientists closely monitored water vapor measurements aboard the aircraft. A spike in water vapor indicated that the plane had entered the outflow plume.
“There’s definitely been some cheering,” said Kate Smith, a post-doctoral researcher at the University of Miami who works with instruments aboard the ER-2. “It’s really kind of amazing that they’re able to predict where [it’s] going to happen.”
The rapid updrafts in thunderstorms can push all kinds of material into the stratosphere, including water vapor and pollutants from both man-made and natural sources. Because the stratosphere has its own delicate chemistry, chemicals from the lower atmosphere could alter it, explained Smith. For example, some compounds can wreak havoc on the atmosphere as they break down and interact with the fragile ozone layer that protects Earth from the Sun’s harmful radiation.
Though scientists have known storms overshoot in the stratosphere, little is known about their interactions with the climate. Some compounds such as water vapor and methane are strong greenhouse gases and contribute to global warming. It’s important to understand their role in the atmosphere to predict how it will change in the future due to human-caused climate change, explains Bowman.
One instrument pivotal to those predictions is the Advanced Whole Air Sampler: a manifold of 32 canisters that collects air samples as the plane flies. The AWAS measures 50 different compounds, including carbon monoxide, methane, hydrocarbons, molecules made up of only hydrogen and carbon, and halocarbons, molecules that contain halogen atoms such as chlorine and bromine.
The halogen-containing gases break down and produce radicals, a kind of free-roaming atom that can destroy the ozone layer, explains Smith, who is part of the AWAS team. Smith and her colleagues are particularly interested in short-lived compounds that typically wouldn’t make it into the stratosphere on their own.
“Because of this chimney type process, where [the storm] shoots them up fast, we can identify and detect some of these species in the lower stratosphere,” added Smith.
Another instrument collecting short-lived compounds is the Compact Airborne Formaldehyde Experiment (CAFE) from NASA’s Goddard Space Flight Center, which measures levels of formaldehyde with a laser-based technique. Formaldehyde measurements help tease apart how air is transported into the stratosphere since only freshly transported air will have formaldehyde in it.
Both CAFE and AWAS will contribute vital information to the mission, but they are just two of a dozen total instruments the team depends on.
“They’re like your children, you know? You love them all equally,” said Bowman.
With the flights finished and the ER-2 back in the hangar, the next phase of the mission is analyzing all the collected data. While the team sampled around 20 storms during their deployment, hundreds more occurred that weren’t sampled. The first step in their analysis will be to use their data to make models that estimate how much collective material thunderstorms eject into the stratosphere. Then, they can start unraveling what that material does when it gets there—advancing NASA’s understanding of Earth’s climate and preparing for the changes ahead.
Freshman and sophomore students from minority-serving institutions joined NASA researchers on a P-3 aircraft based at NASA’s Wallops Flight Facility in Virginia, as part of the Students Airborne Science Activation (SaSa) program coordinated by the NASA Ames Research Center in Moffett Field, California. Carrying instruments that collect atmospheric data, the five flights from July 5-16 followed various paths along the I-95 corridor from Baltimore to Hampton, Virginia, as well as over the Chesapeake Bay.
Several SaSa students wrote personal blogs about their experiences, which are excerpted as quotes in the narrative here.
Flying at altitudes between 1,000 and 10,000 feet – which included low-level passes and several spiral tracks on each outing – had some of the students a little nervous.
“I didn’t know what to expect from my first non-commercial flight. All I knew was that the flight had valuable data related to my research, and all I had to do was endure the spirals to get it,” wrote Neima Dedefo, an aviation science major at the University of Maryland, Eastern Shore.
Dedefo picked the lucky number before takeoff and got to sit next to the pilot during one of the flights. “I sat up front, with the rush of adrenaline coursing through my veins. Listening to the pilots communicate with Air Traffic Control (ATC), looking at the view from my window was a solidifying moment for my career,” she noted.
Trisha Joy Francisco, a mechanical engineering student at the University of Maryland, Baltimore, said she was so excited for the flight she asked the program manager to put her on the first flight.
“Everyone was required to be in the hangar by 9 a.m. sharp for the flight briefing,” Francisco recalled. “Our task as students was to listen, observe and ask questions to gain a better understanding of being in the airborne science field. Watching the discussion felt surreal to me. It felt like I was in an episode of Star Trek watching the officers plan for their missions.”
Francisco said the flight day “was filled with anticipation” because the weather forecast the night before had been for stormy skies.
“7:45 a.m. – that was the moment to ultimately decide if our last airborne science flights were going to take place,” explained Stephanie M. Ortiz Rosario, a physics and atmospheric sciences major at the University of Puerto Rico at Mayagüez. “Pilots, scientists, students, and coordinators gathered at the conference table in the hangar to listen to the information that would influence their decision: the weather briefing.
“And there was me, the one in charge of delivering the forecast,” she said.
“As my first time doing it for the team in real time, it was a nerve-wracking moment, especially knowing that the data I brought in was critical for their decision, and I needed to provide it as clearly as possible,” Rosario said. “The reality is that I was ready to do it. My mentors have been incredible in helping me build up my forecasting and science communications skills. It was the perfect time to showcase myself as a future atmospheric scientist. I just needed to take a deep breath and step in with confidence.
“After what seemed like the most terrifying 3 minutes of my life, I felt the overwhelming support of the team, with their applause and comments. I instantly knew how happy I was to accept the challenge to deliver the weather briefing and see that as a student, my knowledge was useful and appreciated in NASA,” Rosario wrote.
Vanessa Vuong Hua, an environmental studies major with a concentration in atmospheric sciences, University of California, Riverside, did research on trace gases and their impact on the atmospheric chemistry of cities. She was motivated by her concern for her hometown of Riverside, California. “I am no stranger to the poor air quality that plagues the city on a regular basis,” she noted.
“My journey through STEM has been a flight full of missed approaches, spirals, and cruising,” Hua related. “While my destination is not certain, I know without a doubt that environmental science will always be a field I would love to contribute to. In a world where degradation and climate change are occurring at a rate faster than we can prevent it, scientific intervention is more needed than ever. Flying on the P-3 Orion has served to further solidify my passion for atmospheric science and giving back to communities in need of environmental justice.”
Sophia Ramirez, a biology major from California State Polytechnic University in Pomona, has known since middle school that she wanted to follow a career path in science. She noted that “taking off for a flight in a STEM career can be difficult as a first-generation student with little knowledge of resources, guidance, and representation in the desired field.”
“Fast-forward, and I am now in my seat, buckled up, headset on, and ready for take-off,” Ramirez wrote. “As the pilots and head scientist used the headsets to ask each scientist if their instrument was ready to commence take-off, I had a flashback of teachers taking attendance in class. But, instead of doing so to begin class for the day, it was done to begin a flight that would collect atmospheric and Earth data that can be used for research projects and potentially to educate all students of the world about atmospheric processes conditions.”
Ramirez continued, “Throughout the flight, I felt my dreams of becoming a scientist become more tangible, as I saw the science happening in front of me. As I was immersed in science myself. Although I could not take steps with a feeling of stability as I walked down the aisle of the plane, I felt a stability in my career as a woman in STEM.”
SaSa intern Camila Hernández Pedraza, a biology major at the University of Puerto Rico, Cayey Campus, enjoyed a slightly different experience as she traversed the Chesapeake Bay via boat to collect data for her research.
“As an intern in the SaSa program, I enjoy researching, studying, and increasing my understanding of how anthropogenic and natural climate change impacts life,” she wrote. “The most gratifying moment was being able to analyze and relate our findings with my previous studies in biology and chemistry.”
Although she was having a good time and learning as much as she could about water quality, Pedrazza got hit by a rough bout of motion sickness.
“After the boat had docked, I found myself using ice packs and wet towels, while laying at a restaurant with air conditioner and telling myself that everything was going to be okay,” she recalled. “I knew becoming a scientist would be challenging, but I also knew that discovery and answers would be worth it. Despite the tribulations, I strive to thrive, because this is what I love.”
It was a duck that led me to treasure. And a plane that led me to the duck.
I set out that afternoon from Thule Air Base, walking down a gravel road with the Greenland Ice Sheet looming in the distance. I was trying to find an interesting view to film NASA’s Gulfstream V as it came back from a flight measuring sea ice for our ICESat-2 field campaign. I failed miserably, the plane landing as a spot in the distance far away.
Annoyed, I turned around and glanced at a pond of water by the road and spotted a duck – a fancy duck! I’m not a great birder, but I had studied up on the area birds and recognized it as a long-tailed duck. I crept closer to try to take a picture with my cell phone. It paddled away. I crept. It paddled. And then….
On the far side of the pond, a dull brown piece of fuzz blew in the wind, held by a clump of grass.
I gasped, forgot the duck, and ran over.
It was a dream come true for this knitter – qiviut, the undercoat of a musk ox, softer than cashmere, warmer than wool. I picked it up and rubbed it between my fingers – OK, I picked out a little dirt from it first, then rubbed it through my fingers – and had to laugh at how such a delicate and delicious fiber came from such a hulking beast.
Musk ox are found across the Arctic, and we had spotted several the weekend before on a drive out to the ice sheet. (What do sea ice scientists do on a day off of work? Visit an ice sheet, of course!) The first musk ox we saw was just over a mile from Thule Air Base, and I was surprised to see it so close to noisy humans, grazing peacefully in the hilly tundra of northwestern Greenland.
Although there isn’t a huge diversity of mammals in the region, they’ve been easy to spot on this campaign. That first trip beyond the base, we saw three musk oxen and several huge Arctic hares. I’ve started to recognize the Arctic foxes that live under the building I’m staying in, including a skittish brown kit and shaggy adults shedding their white winter fur.
It’s possible the lack of trees makes wildlife-spotting easier. Lack of trees doesn’t mean a lack of flora, however. I was thrilled to realize that our summer campaign overlapped with wildflower season. Yellow poppy-like flowers, white puffballs of Arctic cottongrass, purple petals sticking up from a bed of moss, all thriving in the harsh environment. Walking to the ice sheet, one of the scientists and I fell behind while taking pictures of these hardy plants, growing in the rocky glacial moraine.
Back to the qiviut. I found that first bit, then looked around and saw more. Other clumps were hooked on a piece of wood, or a little flower. Musk ox hoofprints and poop provided further evidence of what had wandered by. I followed the prints and poop, picking up clumps of qiviut, like a kid on an Easter egg hunt. If you ever need to lure me into a haunted cottage in the woods, just leave a trail of heavenly fiber – I will skip merrily into the trap.
Walking back to Thule with a pocket stuffed with musk ox wool, admiring flowers poking up from the side of the road, watching a snow bunting flit across another pond, I know how fortunate I am to explore this unique environment. It’s like nothing I’ve seen before, and I doubt I’ll see anything like it again.
The Arctic is warming four times faster than any other region of the planet. I wonder how these hardy animals and plants, so well suited to their frozen ecosystem, will fare. A recent study described a population of polar bears in southwestern Greenland that now rely on glacial ice, instead of the sea ice that is typical seal-hunting grounds for other polar bears, as the sea ice in their habitat has disappeared for most of the year due to climate change.
As a writer who works with NASA scientists investigating how a warming climate impacts our planet, I’m continuously amazed at how well we can measure change even in these remote places. As a visitor to this incredible spot beyond the Arctic circle, I truly hope these flora and fauna can adapt to this ongoing change.
I can’t quite find the right words to describe summer sea ice from the air – which is unfortunate, since I’m writing this post about NASA’s ICESat-2 summer sea ice airborne campaign.
It’s like miles and miles of shattered glass, these bits and pieces of ice broken apart and jammed back together. It’s like a honeycomb pattern, except, well, more a mishmash of geometric shapes, no neat hexagons. A 10,000-piece jigsaw puzzle of white ice floes and teal melt ponds and dark open ocean? Let’s go with that.
We’re flying above the Arctic Ocean in NASA’s Gulfstream V plane, a repurposed corporate executive jet (the swoosh branding of the previous owner still adorns the stairway). Onboard are two laser instruments that precisely measure the height of the ice, snow, melt ponds and open ocean below. Hundreds of miles above us, earlier that morning, the ICESat-2 satellite flew the exact same path, measuring the same ice. Scientists will compare the sets of data to improve how we use the satellite measurements, and better understand how and when sea ice is melting in the warming summer months.
Lining up the instrument measurements and the satellite measurements is no easy feat. Starting days before, the scientists had gathered in a common room at our hotel on Thule Air Base in northwestern Greenland, comparing the orbit paths of ICESat-2 with weather forecasts of clouds. Clouds are the scourge of summer airborne campaigns in the Arctic – large storm systems can cover almost the entire ocean, and weather forecast models are not as reliable at this high latitude.
But on this first flight of the campaign the clouds clear for long stretches, sending the scientists, instrument operators and yours truly to the windows to oooh and ahhh at the spectacular ice below.
“Now this is the good stuff,” said Rachel Tilling, sea ice scientist at NASA’s Goddard Space Flight Center, as the abstract stained glass mosaic (that any better?) of sea ice appears under sunny skies.
It’s mesmerizing, watching all the ice go past, seeing the cracks between flows and the ridges where the bits of ice have slammed into each other and refrozen. This campaign is particularly interested in measuring melt ponds, bright bits of teal where the snow covering the sea ice has melted and pooled, causing the ice to thin from the surface.
As we kneel in front of the port windows, looking out, the laser instruments are right next to us, looking down. On this flight, Goddard’s Land, Vegetation and Ice Sensor (LVIS, pronounced like The King) is firing its laser to time how long it takes for light to go from the plane to the ice or pond or water and then return; ICESat-2 is doing much the same thing from orbit.
It’s not all smooth sailing, though. To calibrate LVIS, the plane has to do a series of pitches and rolls. In the air. Over the polar ocean. With me on board.
I’m not a huge fan of flying. It’s only been a decade or so that I can fly without imagining a fiery death every time we hit a bit of turbulence. (I know, “physics,” but still.) I tolerate it, though, because I love going places.
But now we’re in a small plane, intentionally doing a series of pitches (up fast, then down fast) and rolls (one wing down, then the other wing). Intentionally. Three times. The first time is the worst, says Nathan Kurtz, ICESat-2 deputy project scientist and the campaign’s leader. Maybe for some; not for me. The first time was kind of fun, I’ll grant you, and there’s video evidence somewhere of me laughing nervously.
The second time: “Isn’t the LVIS calibrated well enough?” was the primary thought in my mind, which is why I’m not an instrument scientist.
The third time, I was regretting the snacks I had brought along for the flight. Look to the horizon, I told myself – right as the plane started its rolls. The horizon quickly disappeared, and then the plane rolled the other way, and it was all ice, and then it rolled the other way….
I closed my eyes, took deep breaths, and imagined the spectacular view, a patchwork of ice and water, that would be there once the plane stopped rolling.
NASA’s Earth Science Data Systems (ESDS) Program Airborne Data Management Group (ADMG) and the Earth Science Data and Information System (ESDIS) Project are holding a two-day NASA Airborne and Field Data Workshop March 29-30, 2022. This workshop offers an opportunity for stakeholders to provide input on ways to improve the usability of NASA airborne and field data. The first day of the workshop will focus on input from data users, and the second day will focus on input from data producers.
As project manager for NASA’s Scientifically Calibrated In-flight Imagery (SCIFLI) group, Dr. Jennifer Inman is used to managing complicated logistics and solving problems ahead of her team’s deployments. Someone needs a new laptop? No problem. A research plane needs new window panels? OK!
The SCIFLI team – which specializes in in-flight imaging – collects data used to predict the aerodynamics of spacecraft launches, flights, parachute deployments, and atmospheric re-entries. In November 2020, they were due to put their skills to work in Australia, observing JAXA’s Hayabusa2 sample return capsule, with pieces of asteroid Ryugu on board. The international mission was called the SCIFLI Hayabusa2 Airborne Re-entry Observation Campaign, or SHARC.
Dr. Inman’s team would image the return capsule – one of the fastest human-made objects to ever fly through Earth’s atmosphere – while flying high above the landing site, Woomera in South Australia, nearly 300 miles north of Adelaide. It was her responsibility to get the SCIFLY team, and all their scientific instruments, to the site.
But the COVID-19 pandemic has a way of putting a wrench into even the most meticulous plans. As countries closed their borders and travel came to a screeching halt, Dr. Inman found herself in a tangled web of changing regulations both at home in the U.S. and abroad.
“It was like Whac-A-Mole, solving one problem at a time,” she said. “And the bad days were days where moles that I’d already whacked, popped their heads back up.”
The SHARC team selected an airliner-style plane, the NASA DC-8 based out of Armstrong Flight Research Center, to carry out their observations. But there was a major problem – the DC-8 was due to have an engine replaced before their trip. However, the maintenance facility was shut down because of the pandemic. The aircraft wasn’t going to be ready in time for the mission.
“We ended up scrambling. And where we settled was that we were going to use two of NASA’s Gulfstream III aircrafts,” Inman said. “But it meant we had to redo everything. All of our plans, all the engineering and analysis.”
The Gulfstream III is much smaller than the DC-8. The gimbals – specially engineered mounts used to secure scientific instruments in the aircraft – didn’t fit the smaller cabins and had to be completely redesigned and rebuilt. The mission computers were also too big. Dr. Inman had to order NASA-approved laptops – a relatively small purchase, but one that can take months to be approved.
Making matters worse, the scientific instruments used to observe the sample return capsule couldn’t ‘see’ through the Gulfstream III jets’ windows – no UV light could pass through them, and their multiple panes would have resulted in images with multiple reflections.
“We ended up borrowing some aircraft windows and window frames, like the actual hardware that got epoxied into the airframes,” said Inman. “We borrowed those from Armstrong, some of them, and had to fabricate additional windows and frames using Armstrong’s design.”
Pandemic restrictions were difficult for collaborators from Japan, too. During normal times, JAXA colleagues would have come to the U.S. to integrate their scientific instruments into the aircraft and perform system checks on their equipment. They ended up having to ship their equipment to Johnson Space Center, in Houston, where they entrusted a NASA team with those tasks. The next time JAXA scientists got to see their equipment again would be in Australia.
And all of this happened before even leaving the U.S. Getting the research planes and essential personnel to Australia in time for the mission were also huge hurdles.
In addition to visa requirements, the team needed special authorization to enter Australia and to travel across internal, police-controlled borders. The rapidly changing situation meant that travel regulations weren’t well-defined, particularly for the NASA aircraft that needed to make several international fuel stops along their route to Australia. Initially, the team didn’t know what types of COVID-19 tests would be accepted or where they could obtain them.
Jhony Zavaleta, mission support specialist from the Ames Earth Science Project Office (ESPO) was concerned that the team wouldn’t be able to provide their test results within a set time frame. “Some of our guys were getting tests, and sometimes it would be 48 hours or maybe a week until results came back,” he said. “There was a lot of uncertainty.”
For the personnel not traveling on the NASA planes, getting to Australia wasn’t any easier. The team faced the prospect of a 42-hour journey, via Qatar, where there were more requirements to provide negative tests and additional documentation. There were also very few flights scheduled – and many of those were being canceled.
As the clock ran down, the team was running out of options. Zavaleta had to charter an aircraft to carry the key personnel to Australia.
Dr. Jay Grinstead, SHARC’s principal investigator from NASA Ames, was impressed by the last-minute efforts: “People were really interested in seeing this mission succeed. So they made concessions and made funding available.”
Zavaleta and a colleague from ESPO made it to Australia ten days early to allow them to set up ahead of the full team’s arrival. “Nobody from our team had been to Australia before to plan,” he said. “We didn’t know what the situation on the ground was.”
Normally, key details like where to buy supplies and the team’s transportation would be sorted six months in advance. But now, the team didn’t know what restrictions would be in place by the time they arrived, who would be supporting them, or even what hangars their planes would be in. The instruments also needed to be calibrated, and Zavaleta had to make sure the hangar operators were aware of the team’s needs and willing to work off-hours. It was an incredibly tight turnaround.
Despite the numerous setbacks, the mission was a huge success, largely due to the collaboration between Dr. Inman’s team, the aircraft organizations at both Langley Research Center and Johnson Space Center, ESPO, NASA Headquarters, JAXA, the Australian Space Agency, and other Australian officials. Dr.Grinstead said, “We really could not have pulled this off without our international partners.”
Far up in northern Alaska, Logan Berner’s legs are burning with pain from trekking over tussocks in grassy valley bottoms and rugged, cloud-choked mountain passes. He’s spending a couple of weeks of 2021’s summer traversing the mountainous Brook Range, carrying just the essentials to sustain him in the expanse of the Alaskan Arctic. There, where North America ends, tundra and mountains make up one of the continent’s most pristine landscapes.
The Brooks Range is not the sort of environment where people just go for a hike. It’s too remote, too wild, and too cold. There are no human trails other than what’s left behind by moose, bears and other wild animals roaming the region. It’s the kind of terrain that will get you in trouble, the kind that would put you face to face with a hungry grizzly bear or give you hypothermia.
Rain gear is non-negotiable. 2021 marked one of the wettest summers on record in the range, and some days in the trek feel like an endless walk through a car wash. Stopping for more than a few minutes (even to eat) will make your body too cold from the whipping wind and pouring rain near freezing temperatures.
Berner, a research ecologist from Northern Arizona University, went out there to join a group of biologists led by Roman Dial, a professor of biology and mathematics at Alaska Pacific University who had been traversing the range on foot for nearly a month. Covering nearly 800 miles in about three months, the team used their smartphones to take pictures and jot down extensive notes about the vegetation they passed, noting when and how the type and density of trees, shrubs and other plants changed along their way.
By combining those notes with techniques that analyze greenness from space, the team wants to gain a better understanding on the extent and nature of the impacts of climate change right at the boundary between Arctic tundra and boreal forest. The idea is to use that data, recorded the old-fashioned way with boots on the ground, and link them with NASA’s long-term satellite observations.
The Arctic is warming nearly twice as fast as other regions on Earth, and the impacts extend beyond glaciers melting, sea ice shrinking and other types of vanishing polar ice. They reach most deeply into places such as the Brooks Range, where Arctic tundra—a harsh, treeless ecosystem where mostly small plants grow—has become increasingly greener.
Over the last four decades, satellites have detected that greening, as well as some browning, where extreme weather, insect pests, and other disturbances reverse the greening trend. But even though satellite records suggest Arctic tundra ecosystems are changing in response to atmospheric warming, important details remain unclear about why specific regions have greened or browned in recent decades.
“Arctic greening is really a bellwether of global climatic change,” Berner said. “We know that this greening signal in part reflects warmer summers, increasing the amount of plant growth that’s occurring on the landscapes, so that the satellites are seeing this increase in leaf area.”
Already, the effects of these vegetation changes point towards other impacts as the Arctic tundra becomes more productive and shrubbier.
For example, Berner explained, thriving shrubs could out compete smaller plants that serve as important subsistence resources, like blueberries, which help sustain northern human communities. Dial also has observed that these vegetation changes can re-shape the landscape and affect how caribou and other migratory animals navigate the Brooks Range, also affecting the availability of subsistence resources for isolated villages depending on wildlife.
On the flip side, new spruce tree forests can also help insulate the thawing permafrost and possibly reduce the release of deep pools of carbon stored within it, adding more heat-trapping gases into the atmosphere.
“In that sense, [greening] might slow the rate of climate change by keeping that organic-rich permafrost carbon soils frozen and locked away,” Berner said.
Because of the unknowns revolving around Arctic greening and browning, field data serves as a crucial complement to satellite observations. Gradients of vegetation stripe the Brooks Range, making it an ideal location to sample from, as the mountains form a natural barrier that separates the boreal forest of Alaska’s interior from the Arctic tundra of Alaska’s North Slope.
NASA’s satellites can track large-scale vegetation changes from space. But 700 miles up in space, they mostly get a top-down view of the terrain. By venturing into the wilderness to collect the extensive ecological field data that is impossible to capture from space, Berner and Dial’s team are helping the satellites “see” more and better.
The team is combining their detailed notes from the ground with satellite observations of the region by the Landsat program. Ultimately, linking both datasets can help scientists learn more details about where, why, and how large patches of the Arctic’s flora are changing.
“Being on the ground and walking through these landscapes gives you a much better sense for what these landscapes are,” Berner said. “It gives you an understanding of these ecosystems that you just can’t get by sitting at a computer and crunching data.”
The team was able to trek and take data largely thanks to Dial, who has travelled over 5,000 miles throughout the Brooks Range during the last four decades. As part of that exploration, Dial developed ingenious ways to travel light for extended periods of times, making it more manageable to collect data from the field.
“When doing fieldwork in remote Arctic, Antarctic and alpine environments, survival comes first, so you can sometimes feel lucky to perform any research along the way at all,” Dial said. “But our methods of travel have evolved to the point where we can travel light and comfortably—dealing with rivers and bears and rain and wind. By integrating that light and comfortable mode of travel with smartphones and simple tools like tape measures and tree increment borers, as well as other apps on our phones that can measure heights, we can actually collect valuable and useful data across vast swaths of wilderness.”
What really makes recording data on the field possible is what Dial named “pixel walking,” a unique way in which a group of trekking scientists document observations about the vegetation as they see it on the ground, logging changes in plant types, attributes, and location continuously. Their protocols to record that information cover 30-square-meter plots of land, or a pixel of a view from a Landsat satellite.
Most previous field research has involved establishing field plots and meticulously characterizing the plant community in each one. That does provide valuable information, but the approach is expensive, limited in extent and time-consuming. Because field plots tend to be small and few, it can be difficult and prohibitively expensive to cover large areas accurately, and to match them with observations from space.
With a smartphone app developed by Dial’s team, the trekkers note the tallest plant community and its physical structure as might be seen from an orbiting satellite. They also record what isn’t so easy to see from space: the understory and ground cover. As they walk, they record on their smartphones’ app the identity and density of each of three layers of vegetation. The app also records the geographic location with the phone’s GPS.
“It’d be very expensive to collect this kind of data with a helicopter,” Dial said. “This is a really important aspect of ground truthing and calibrating what the satellites see with what’s on the ground. From satellites we only know that the reflectance values are changing over time, but we don’t know what it is that’s changing on the ground. So this is a way to find out what is really happening with plant communities and the Earth’s surface and relate it to the last 20 years of satellite data.”
Berner, supported by NASA’s Arctic Boreal Vulnerability Experiment (ABoVE for short) and Dial’s team, supported by NASA’s Alaska Space Grant, the National Science Foundation’s Established Program to Stimulate Competitive Research, and the Explorers Club/Discovery, are already working to link their field observations with satellite data. What they’ll learn can also help inform future research in other parts of the Arctic.
“What is the greening that we see? Is the greening an increase in willows, for example? Is it an increase in birch? Or is it an increase in alders? Or is it an increase in trees?” Dial said. “Having a small team like mine actually on the ground to provide the ABoVE program with ground-based data—that’s really what ABoVE is doing well. It’s just a really wonderful marriage between field data collection and remote sensing.“
Launch day dawned gray and cool, with low-hanging cloud cover and a light drizzle. While the launch crew ran through their final procedures and checks before launch, I went to the public viewing site at Lompoc Airport, where several tents’ worth of activities and a “not-quite-life-sized” cutout of Landsat 9 greeted visitors.
In the activity tents, families were solving floor and table puzzles with Landsat imagery, while members of the outreach team helped kids make colorful mosaic art, use “pixel” stickers to reconstruct an image, and understand how satellites measure sea ice.
Ten minutes before launch, the tents started to empty out as people moved toward the open airport runway that pointed toward the launch site, about 10 miles away. I moved into the VIP viewing area reserved for NASA personnel and invitees. Some settled in for a view from bleachers or sheltered under a tent; some trekked far down the empty runway. I decided to head down the runway and try to get a glimpse of the Atlas V rocket as it cleared the launch pad.
Because of the low-hanging clouds, our view of the launch was three seconds of bright flaming light on the horizon before the rocket was swallowed up in the gray sky. Even from ten miles away, however, I could see the exhaust clouds billowing up from the launch pad and hear the earth-shaking, deep bass roar of the powerful engines powering the rocket toward orbit.
The gathered crowd strained their eyes eagerly toward the sky, hoping to catch a glimpse of the rocket as it hurtled toward space. Some people embraced as they felt the sound wash over them; some pointed or shaded their eyes; some cheered and clapped, while others stood quietly to listen to the rocket’s roar arcing high into the sky and overhead.
The payload and booster reached orbit about 16 minutes after launch, and Landsat 9 separated from its booster about an hour later, joining Landsat 8 and the rest of NASA’s Earth-observing fleet.
One special guest at the airport was Virginia Norwood, affectionately known as the “Mother of Landsat.” Norwood and her team designed and built the Multispectral Scanner System aboard Landsat 1, half a century ago.
Landsat 9 is safely in orbit and ready to start collecting data and taking its place in the nearly 50-year legacy of Landsat Earth observations. But that legacy is not only Landsat’s critical data continuity and technical achievements – it is also the legacy of the engineers, scientists, technicians, and resource managers who keep the program thriving, decade after decade.
It’s a smoky Saturday evening in the small town of Lompoc, California, and most of the streets are quiet — except for the warmly lit tables and flickering tiki torches in the outdoor dining area at Hangar 7. It’s Landsat Trivia Night, and the small restaurant is bustling with about three dozen scientists, engineers, project managers, and techies of all sorts from NASA, the U.S. Geological Survey, and the United Launch Alliance. They’ve gathered under the lights to enjoy pizza and drinks and to show off their knowledge of the 49-year-old Landsat program and its nine satellites.
I take my position along a stucco wall with a huge mural of local plants and animals and listen as the teams rev up for their first question.
“What was the name of Landsat 1 at the time of its launch?” The voice comes from Ginger Butcher, Landsat’s outreach coordinator. Guests lean in to discuss.
Not being a participant, I quietly check Google for the correct answer. It’s ERTS, the Earth Resources Technology Satellite. Launched in 1972, Landsat 1 / ERTS was the first satellite launched to space with the goal of studying and monitoring Earth’s land masses, and it pioneered the science and technology that undergirds much of our Earth-observing research today.
The teams hand Ginger their guesses on pieces of paper. Unsurprisingly, most get the question right. Many of these people have spent years working in the Landsat program, whether as program managers guiding the satellites from concept to launch, engineers overseeing construction and testing, or scientists interpreting Landsat data.
The next question is harder: Cartographer Betty Fleming discovered a tiny island about the size of a football field using Landsat 1 satellite imagery. Off the coast of what country is Landsat Island?
Landsat Island, I learn, is off the coast of Newfoundland in Canada – and the person who verified its existence almost died while doing so. You can read the full story here, but suffice to say, it involved a scientist who got swatted at by a polar bear while being lowered onto the island by helicopter. (Spoiler alert: he survived.)
I’m impressed when several teams get that question right too. The third one, though, I don’t need Google to answer.
“Set in 1973, a year after Landsat 1’s launch, what origin story movie did Landsat play a role to locate an uncharted island in the Pacific?”
The 2017 film “Kong: Skull Island” features Marc Evan Jackson, who plays a NASA scientist named “Landsat Steve.” Jackson also partnered with NASA in 2020 to narrate the “Continuing the Legacy” video series. Nearly every team gets this question right.
In a break between rounds, I chat with a team that named itself ERTS-1. At the table is Steve Covington, principal systems engineer for USGS’ National Land Imaging Program.
“I’m feeling great about launch on Monday,” he said. “It’s going to be cloudy, but I think it’ll be very successful. I’m excited about Landsat 9 getting up there and joining Landsat 8 — and giving Landsat 7 a well-deserved rest.”
Landsats 8 and 9 will work together to cover all of Earth’s land masses every eight days — cutting in half the current 16-day coverage time. Covering the Earth more frequently means scientists can detect changes that happen over a few days instead of a few weeks, giving them more insights into what’s happening on our planet’s land surface.
The group’s enthusiasm for the mission and the launch spills over into the festive atmosphere of the game. And at the end of the night, the grand prize goes to the New Originals — a group of Landsat communicators, educators, and scientists that includes Landsat 9’s project scientist, Jeff Masek.
Events like trivia night highlight the celebration and camaraderie surrounding a satellite launch, which, for many, often represents a pivotal moment, a demonstration of many years of hard work. When Landsat 9 launches Monday, it will continue a legacy that stretches back nearly 50 years, and includes decades of human stories as well as scientific ones — an achievement that is anything but trivial.