Why the spring peak in Greenland field activities?

Field activities in Greenland are often confined to spring and summer. In autumn and winter, low temperatures, snowfall, the lack of sunlight, and more frequent storms do not provide optimal working conditions. Besides, the most interesting processes to study primarily occur in the warm season, such as the melting of the glaciers and ice sheet.

There are two distinct peaks in Greenland field activities. The first is in spring, for those people who need to get out there when things are still frozen, but when daylight and weather conditions are workable. The second peak is in mid-to-late summer, when weather conditions are best, melting is strongest, and the ice sheet margin and tundra is snow-free and more accessible. In between there is a potentially less pleasant period with often soggy conditions, and billions of mosquitoes. With the summer peak getting underway, let’s see what the spring rush is all about.

Installing instruments before the warm season

A good reason to get over to Greenland in spring is when you want your instruments in place to monitor what’s happening during the “warm” season, when plants grow, animals reproduce, and glaciers melt. Or, in the case of the University of Fribourg, when meltwater is generated at the top of the snowpack on the ice sheet. The Swiss scientists have now returned several times to the same sites in the lower accumulation area. They study how much meltwater gets refrozen in the cold snow underneath the surface, how much runs off into the ocean, and how this will change in time. Greenland Guidance provided weather forecasts for them to optimize their activities and prepare camp for storms, if needed. This spring their field team had two weeks on ice with surprisingly good weather conditions.

The University of Liverpool placing a weather station next to a fast-moving glacier (photo: James Lea).

Another team out there this spring was the University of Liverpool, who where installing GG-built instruments at a fast-flowing glacier in southwest Greenland. They are investigating a glacier that has retreated a lot in the past few years. When such a glacier experiences melt, an already complex system becomes even more complicated, for instance because of large pulses of meltwater originating from ice-dammed lakes along the sides. Or from rain events. With their instruments up and running in mid-May, they timed it well.

In May and June, the Geological Survey of Denmark and Greenland (GEUS) visited GC-Net weather stations high on the ice sheet. This is part of their annual maintenance efforts that take place in spring to make sure all systems are up and running during summer. We were invited along to help out. Each station takes several hours to service, but the more people can help, the faster the Twin Otter airplane can return to town. The machine experienced engine trouble, but luckily this happened at the airport before departure, and not on or over the ice sheet.

Preparing for takeoff to do maintenance at GEUS GC-Net sites (photo: Ken Mankoff).

Snow conditions

A second reason for the GC-Net maintenance to take place when it is a bit colder has to do with snow conditions. The scientists need to dig deep snow pits to asses the mass of the snow that fell since the last site visit, and this is done best before seasonal melting happens.

For others a cold snow layer means increased safety. Ski traversers crossing the ice sheet have to pass crevasse fields, and this is done much more safely if there is a solid snow bridge on top, deposited during winter. When snow gets wet because of melting, such bridges get weaker, and falling through them into a deep crevasse becomes a serious threat. That’s why the wind-powered kite-ski traverse team led by Bernice Notenboom did their expedition before the melt season, in May. They traveled an astonishing distance of nearly 2000 km from ice sheet base Dye-2 to the northwestern town of Qaanaaq. During their expedition they were confronted with several storms that we warned them about via satellite transmission.

The Winds of Change kite-ski camp

Preparations for summer

Often spring activities are mere preparations for summer expeditions. Take for instance the greenhouse in Narsaq in south Greenland. In order for charitable organization Greenland Trees to be able to plant trees along south Greenland fjords at the end of summer, their new greenhouse had to be prepared for growing seeds and cuttings in April and May. It took a lot of effort, but is was truly nice to notice how happy locals are with the project, and how eager they are to collaborate – including schools.

The Greenland Trees greenhouse in Narsaq.

In terms of volume, most of our clients and collaborators are scientists or camera crews, asking where to rent a boat, how to get permits, which locals to interview, and how to get to a remote site. But we also provided support to Swedish company SKB, who have been running and funding science projects in the Kangerlussuaq region over the past 15 years. In preparation of a groundwater sampling campaign to occur at their unique bedrock borehole in late summer, we went ahead and inspected the state of their equipment, inventoried their storage, and downloaded data collected by sensors deep underground.

The SKB bedrock borehole at the ice sheet margin.

With SKB discontinuing their Greenland science projects as of 2022, Greenland Guidance was selected to take over their surface hydrology project situated in the Two Boat Lake catchment. This is an exciting opportunity, and we welcome suggestions for scientific collaboration by anyone who reads this. More about the TBL project in an upcoming blog post!

Two Boat Lake with the ice sheet in the background.

Busy times

For Greenland Guidance, spring is the busiest time of year. This is when we support field parties remotely, take part in fieldwork ourselves, prepare for fieldwork in summer, and custom-build instruments for summer deployment. Nowadays we are also building and refurbishing instruments for use in the Himalayas for Utrecht University and the Indian Institute of Technology Roorkee. And we’ve expanded our area of expertise by now also focussing on ocean sciences through collaboration with MetOcean in Canada, and our new instrument platform Polar Monitoring.

Climate science enabled by Forloh

The glaciers in south Greenland are the canaries in the coal mine. They are located in the warmest part of Greenland. As the climate warms, glaciers further north will experience similar conditions in the future. So to learn about the future fate of the Greenland ice sheet, we must study how south Greenland glaciers fare in present-day climate conditions. For this reason we installed 3 draw wire ablation trackers (DWIATs) in south Greenland, and more instruments will follow. An important difference with most other science projects is that this project got funded by a pioneering, US-based company named Forloh.

Forloh site 1 as seen from above. The DWIAT instrument is located between helicopter and moulin (meltwater drainage hole).

For Greenland Guidance it all started when we were approached by Greenland logistics guru Kathy Young who was in touch with a company eager to contribute to climate science. A company appropriately selling warm outdoor clothing. Forloh was seeking to sponsor climate science in a cost-effective manner. With Greenland Guidance’s non-profit approach to science, a match was soon in the making.

Our missions with the instruments in south Greenland is not only that the observational data are shared freely with researchers across the globe, but also that the measurement locations are optimal for scientists. For this reason we asked the research community where they could see most value in having DWIATs monitor ice melt and motion. After this we decided on 3 sites requiring only short helicopter flights in south Greenland.

Winter temperatures – an example of Forloh scientific data displayed in the GG data portal. DWIATs also measure surface melt, latitude, longitude, altitude along with several system-diagnostics parameters. Note how DWIAT 1 got covered by winter snow accumulation judging from a reduced temperature variability on the right-hand side of the graph. But satellite transmissions keep coming in.

One monitoring site is right next to a moulin (meltwater drainage hole) on the main ice sheet. The second instrument is on the large, fast-flowing glacier named Eqalorutsit Kangilliit Sermiat (often called Qajuuttap Sermia) which is receiving increasing amounts of scientific attention these days. The third is on Nordbo glacier (Nordbogletsjer), a historic site where ice melt was also measured over 4 decades ago, providing an excellent opportunity to study the impacts of climate change since then.

Kathy Young and Steve Munsell, GG support crew along with Armin Dachauer, on Eqalorutsit Kangilliit Sermiat (also called Qajuuttap glacier) after installing a DWIAT.

Our helicopter charter took place on a Thursday in August. We were spared any weather delays, which are not uncommon when flying in Greenland. Our first site took some scouting as we had about 20 moulin candidate sites selected from satellite imagery. The second and third site were know before arrival, chosen to avoid crevasses and to match the historic measurement location, respectively. Instrument assembly/testing and drilling the draw wire into the glacier took 30-45 minutes per site. Even though the drilling at these wet sites proved difficult, we managed to stay on schedule, leaving some time for collecting footage at the spectacular moulin site.

We very much invite other scientists to collaborate scientifically or logistically in this project. Please do get in touch if you’re active in the region and have specific data needs.

The Forloh study area in south Greenland in red. The blue area contains GEUS PROMICE instrumentation. The red area is where Greenland Trees is active. Eqalorutsit Kangilliit Sermiat is the large glacier in the middle.

Revisiting ice monitoring equipment along the K-transect

Last summer, Greenland Guidance was again invited to assist with instrument maintenance on the western slope of the Greenland ice sheet. Here, along the iconic K-transect, Danish and Dutch scientist have been using automated measurement systems to monitor climate variables and surface ice melt for decades. As these weather stations, ice ablation trackers and other scientific measurement systems are exposed to harsh weather such as low temperatures, high wind speeds and countless thaw/freeze cycles, they need to be looked after once a year.

The PROMICE weather station at GEUS monitoring site KAN_L.

As in previous years, the Geological Survey of Denmark and Greenland (GEUS), the Institute for Marine and Atmospheric Research Utrecht (IMAU) and Greenland Guidance joined forces to visit all 10 measurement sites. Unlike the year before, the weather was reasonably well behaved; clouds and winds did not interfere too much with helicopter operations. In the higher ranges of our work area though we encountered a thick layer of saturated snow. Uncommonly warm air masses were over the ice sheet causing a serious melt event, severely complicating moving about in the soft, wet snow.

A draw wire ice ablation tracker one year after deployment.

Most equipment was found in good working order, requiring between 15 minutes and 3 hours of ground time per measurement site. The good news for Greenland Guidance was that all 4 custom-built draw wire ice ablation trackers (DWIATs) were fully functional and transmitting ice melt and motion data home.

A moulin fountain, spraying ice sheet meltwater 10 m up into the air.

One of the highlights of the 5-day fieldwork campaign was the sighting of what is best described as a “moulin fountain”. This rarely seen phenomenon occurs when overpressure from a large moulin (meltwater drainage hole in ice) is released via a crack in the ice to a smaller, neighbouring moulin.