Science Under the Midnight Sun

Nestled on the west coast of Greenland, the village of Ilulissat — a Kalaallisut word that translates to “icebergs” — has a population of 4,670 and is home to almost as many sled dogs as people. Brightly colored Scandi-style buildings cluster together near the iceberg-filled water’s edge.

Inside a cozy cottage near the water, the sounds of spoons clinking coffee cups, zippers zipping and buckles buckling began in the early-morning hours. Colby Rand, WWU environmental sciences grad student, and Molly Adshead, ‘23, B.S., environmental science and post-bac lab technician, huddled around a small kitchen table for a breakfast of tinned kippers on crackers before a 15-hour day on the Greenland Ice Sheet.

Both Rand and Adshead are polar-research veterans. They have traveled to Antarctica multiple times over the past few years with funding from WWU Environmental Sciences Associate Professor Alia Khan’s NSF CAREER Award. They went to Greenland in July to continue their work studying the impact of algae and black carbon deposition on snow albedo — a term used to describe how much light and heat are reflected by the snow’s surface.

Rand, of Bangor, Maine, earned a bachelor’s degree in earth and climate sciences with an emphasis in glaciology from University of Maine before coming to Western. He specializes in measuring how different wavelengths of light reflect off snow and ice surfaces. More specifically, he concentrates on the remote sensing, drone flying and satellite-imagery analysis aspects of this work.

“I focus on the mapping, but broadly, we want to understand how various particles darken the surface of the ice sheet and impact snow melt,” says Rand.

As a grad student at Western, Rand worked in the field with Khan on the Juneau Icefield, on Mount Baker and in Antarctica mapping snow algae. Rand published two papers evaluating the capabilities of commercial small satellites for this kind of mapping before bringing his expertise to the Greenland Ice Sheet.

Adshead, of Coquitlam B.C., earned her bachelor’s degree in environmental sciences at Western. In the field, she specializes in collecting and preserving frozen samples for analysis back on campus.

After breakfast, the team, led by Khan and accompanied by WWU Director of Visual Media Production Sean Curtis Patrick, loaded hundreds of pounds of equipment — drones, replacement batteries, sample collection tools, coolers and more — and headed out to the helicopter pad to catch their ride onto the ice sheet.

You’ve probably heard: Iceland is green, and Greenland is icy. And like many elementary school mantras, it’s rooted in truth. Nearly 80 percent of Greenland is covered by an ice sheet. But what does that mean?

An ice sheet is a mass of glacial land ice formed by accumulated snowfall that exceeds annual melt. But ice sheets are much larger than glaciers. By definition, an ice sheet is more than 20,000 square miles in size and can cover underlying canyons and mountain ranges. Since the end of the Pleistocene ice ages, there are only two ice sheets left in the world: One covers most of Greenland, and the other stretches across Antarctica.

The magnitude of these masses of ice is difficult to grasp. According to the National Snow and Ice Data Center, the Antarctic and Greenland Ice Sheets together contain more than 99 percent of the land ice and over 68 percent of the fresh water on Earth.

“I’ve never seen anything like it,” Adshead says. “Huge expanse — a 360 view! Just ice, streams and lakes, which were all so beautiful. Just the clearest blue you can imagine.”

The Greenland Ice Sheet spans 656,000 square miles — an area roughly the size of Mexico, or about three times the size of Texas — and is 1.9 miles thick at its thickest point.

Big, right?

Importantly, the Greenland Ice Sheet is in its 29th consecutive year of ice loss. Seasonal snowmelt on the ice sheet is one of the largest contributors to sea-level rise, with the staggering potential to contribute 7.4 meters — more than 24 feet — to global sea-level rise if melted in its entirety.

Sea-level rise is a global phenomenon and already directly impacts one billion people around the world — including the 70 percent of Washington state residents who live near the coast. Coastal communities, economies and delicate ecosystems face an existential threat, but the effects of sea-level rise don’t have distinct borders. Roads, waterways, power plants, oil and gas wells, drinking water and supply chain systems that serve all of us are at risk. Likewise, the increased costs of coastal protections are borne by everyone.

The more we know, the better prepared we’ll be to predict, plan for and face these challenges.

WWU graduate student Ella Hall accompanied Khan last year on an NSF-funded expedition to Greenland to set up instruments designed to measure aerosols on the ice sheet. This past spring, Hall began analysis on her data set.

“Already from preliminary statistics, I’m seeing a significant correlation between albedo and smoke deposition over time,” Hall says. “This is a positive feedback loop — the surface of the Greenland Ice Sheet is getting darker, so snow is melting faster.”

Snow plays an important role in managing heat from the sun and insulating our planet by reflecting large amounts of incoming solar energy back into space. Fresh snow’s albedo, or reflectivity, is very high and typically can reflect 80 or 90 percent of solar energy back into the atmosphere and beyond.

Trees, plants and soil have more light-absorbing particles and reflect only 10 to 30 percent of sunlight, according to the National Snow and Ice Data Center. Dirty snow contains light-absorbing particles like algae, mineral dust and black carbon — the wildfire soot that Rand and Adshead came to measure — so it has much lower reflectivity, or albedo, than fresh snow and absorbs higher amounts of solar energy, leading to increased melt.

Snow algae occurs naturally. But the WWU team is exploring an uptick in black carbon deposition on the surface of the Greenland Ice Sheet that can be traced back to a recent surge in North American wildfires, particularly in Canada. Canada’s 2023 wildfire season was their most destructive yet. More than 6,000 fires torched 15 million hectares of land — an area larger than England. That’s six times more than the annual average consumed by wildfires in Canada.

Smoke and black carbon from those fires drifted through the atmosphere and found a new home on the Greenland Ice Sheet, absorbing light and heat just like a black sweatshirt on a cold, sunny day.

After a short flight about 30 miles into the desolate ice sheet, the helicopter pilot dropped off the WWU research team and their equipment and didn’t return for 15 hours.

“I’ve never been on an ice sheet before. It was just really cool, seeing the vast expanse of ice in all directions. It was very cold and windy, but we were prepared,” says Rand.

But the stunning landscape is not without risks. Subzero temperatures and biting polar winds are a given. Visitors also have to be prepared for instability of the ice, meltwater, polar bears and more.

The WWU team surveyed their work area for crevasses and supraglacial streams, which flow along the top of the ice sheet in the warmer months. The clear glacial water is alluring but can be dangerous if a person falls in and gets swept away. Supraglacial streams drain through moulins, or vertical shafts that carry meltwater from the surface down to the bedrock. Moulins can change shapes within days in the warmer months, so it’s imperative that researchers take care around streams and lakes.

“We were worried about crevasses on the ice sheet, but where we were was relatively flat. We didn’t have to use our harnesses or anything,” says Rand.

And there’s always potential for polar bear encounters on the ice sheet, a low-probability but high-consequence risk. As the saying goes, “If you see the polar bear, it’s too late.”

Even so, the WWU team took turns monitoring the horizon for bears with binoculars and carried a bolt-action, .308-caliber semi-automatic rifle, just in case.

“We hit a wall at 3 a.m. during our 15-hour shift on the ice. We set up a screen of coolers and boxes to try to block the wind, but it never even stopped for one second,” says Adshead. “We wrapped ourselves in emergency blankets under the midnight sun and tried to take a nap, but we had no insulation between us and the ice. Then you look over and Sean’s sitting guard in a camping chair with a huge rifle. I have no memory of sleeping that night.”

Rand’s most recent trip to Antarctica was last February. Coordinated through Khan’s ongoing research collaborations, Rand spent a month down there mapping snow algae with drones and satellite imagery from a Chilean base.

“Snow algae primarily grows on the snow’s surface in remote areas,” says Rand. “It’s difficult to travel to these areas, costs a lot of money and the terrain is dangerous to traverse. Remote sensing makes it a lot easier to study changes on the snow’s surface without having to go there ourselves.”

Before going out in the field, Rand programs an automatic flight mission for his drones. By stitching together hundreds or even thousands of drone photos with a technique called Structure from Motion, he builds a 3-D model of the landscape. Rand then applies image-processing tools to map out where the snow algae is located.

This summer, Rand took these methods to the Greenland Ice Sheet.

“I’m toward the end of my master’s program here now, and I’ve already defended my thesis,” Rand says. “During my three years at Western, I’ve learned to use the tools and the drone technologies we have to get the images we need. Greenland is a culmination of all the skills I’ve learned, and it’s really cool to put it all into action on the ice sheet.”

Adshead got plenty of practice collecting samples in Antarctica and brought this expertise to Greenland. She used a steel chisel, an ice screw and a ceramic knife to collect 50 viable samples of the Greenland Ice Sheet. She stored them in glass vials and Whirl-pak bags and packed them in coolers with glacial ice until they were ready for processing.

“I was in charge of collecting samples and making sure we followed certain protocol,” Adshead says. “The tool has to be cleaned between samples, and samples have to be stored properly so they don’t deteriorate post-collection. I had to make sure they get back to the lab safe and sound as soon as possible.”

Part of Adshead’s work is learning how to unmix snow algae from wildfire black carbon. She wants to understand more about each component involved in reducing the snow’s reflectivity.

“I have collected a lot of snow algae — in Antarctica and elsewhere — and this was the first time I got to see ice algae that form cryoconite, which is made up of soot, sediment and microorganisms. They form these little holes in the ice, and that was really interesting,” says Adshead. “So we are looking at that now and seeing what the composition is, identifying algae and other microorganisms. It’s fascinating to see the interplay of various components and how each contributes to darkening the surface of the ice.”

Rand’s work and Adshead’s work go hand-in-hand, and their findings will be dependent on each other’s contributions.

“It’s hard to see from the drone imagery the difference between ice algae and non-biological components darkening the surface,” Adshead says. “I’m working on developing new methods to study pigment concentrations in the ice algae — mostly just trying to find out what the concentrations of each component are.”

Rand says he can’t map effectively without knowing what the lab samples show.

“I fly the drone, and Molly gets all the samples,” he says. “So we can directly compare our findings, and I’ll be able to use that data she’s getting with her work.”

When all the samples were safely packed in their coolers, Rand and Adshead bade a bone-chilling farewell to Greenland with a polar plunge — in polar bear territory — in the iceberg-strewn waters of Ilulissat.

“Who could say no to a polar plunge with a towering iceberg in the background?” says Adshead. “But I definitely had to convince Colby to do it.”

The morning after the team returned to Bellingham — following an exhausting series of flight delays — Adshead rushed back into the lab on Western’s campus. A group of undergrad students in Khan’s lab helped filter and process the samples before they begin to deteriorate. In the coming weeks, the team would analyze their data and work to establish sound methods for unmixing various types of particles found on the ice sheet.

Khan says Rand and Adshead are exactly the kinds of students she wants to work with.

“It’s super rewarding because working with students like Colby and Molly — they are motivated, enthusiastic students who are not just trying to get their thesis or a single project done and get out the door,” Khan says. “They see the impact of their work on the larger scientific community, and I can see them wanting to revise their data analysis to make it as impactful as it can be. I feel very fortunate that my students are interested and invested and recognize the opportunity in these really remote parts of the world.”

The data gathered on the ice sheet will go into a snow and ice database Khan has built from samples across the world, from the Himalayas to the Andes and from Antarctica to Greenland. Incorporating data from Rand’s satellite and drone imagery will provide a fuller picture of spatial and temporal distribution of snow algae and black carbon deposition across the global cryosphere.

This work will shed light on patterns of increased melt on the Greenland Ice Sheet. Our global understanding of and preparation for sea-level rise all depends on the accuracy of our forecasts for snow and ice melt.

The Greenland Ice Sheet has lost more than five trillion tons of ice since the early 2000s. The numbers fluctuate based on weather patterns, but for now, it can be boiled down to this: In the last two decades, the ice sheet has lost an average of 277 gigatons per year (a gigaton is one billion tons).

And as the surface gets darker, the ice melts faster.