Ice Melt and Motion Measurements on South Greenland Glaciers
Why Doing Science in Greenland is Important
Google map showing the locations of the FORLOH-sponsored glacier monitoring sites in Greenland.
Rugged Instruments in Extreme Climate Conditions

Slides And Caterpillars


Ice Melt Larger Than 40 Years Ago

The Complexity Of It All
The below graph shows how it all fits together at site 3; ice velocity, thickness and melt all interact. You’ll see two things that you couldn’t tell clearly from the previous graphs. The first is that the altitude drop that starts in early summer is largely due to melting. This makes sense: ice flow transports the ice into the area, and melting removes an approximately equal amount of mass. If it didn’t, the system wouldn’t be in balance, generally speaking.
Pictured: The data collected at site 3 combined in a single graph. Note the different Y-axis for the yellow lines on the right-hand side.
"The second thing to notice about the graph is that the high-frequent changes in ice velocity and thickness correlate pretty well. But ice thickness seems to be leading on most occasions: first the ice thickens/thins, and then, as a result, the ice starts moving faster/slower."
In Hard-To-Reach Places, Collaboration Is Key
We think it is imperative that scientific data are collected for the good of everyone. That’s why our data is open-access, available to anyone across the globe. You are more than welcome to have a look at the data at https://greenlandguidance.com/measurements/data/forloh/. If you’re a scientist (or student or teacher or just someone with an interest in glacier data), we can send you a batch of raw or processed data for you to use in your research. We’ll also upload the data to the servers of the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) where scientists can download all sorts of important glaciological data and use them for generations to come.
The open-access nature of science becomes even more relevant in remote places, where transportation (by helicopter) is expensive and opportunities for visiting hard-to-reach field sites are few. Therefore we are excited that the large Swiss Green Fjord project chose the same region to study, resulting in data exchange and logistical collaboration. Likewise, the Geological Survey of Denmark and Greenland, already active in the region for decades, chose FORLOH site 2 to install a phase-sensitive radio echo sounder - a radar system for studying processes at the glacier bedrock, putting our data to good use.
Looking Forward
So the data have given us some first insights into the workings of the ice sheet and the interaction with the climate. Data is flowing towards climate scientists and whoever else shares the passion. This will help with better interpretation of satellite imagery in ice sheet studies, and with more precise computer models predicting the future state of the ice sheet. The more measurements we take, the more we contribute to climate science, especially in a remote and special place like Greenland. Because only few such measurements exist.
But perhaps the most relevant will be to see how ice melt and motion will change in the coming years, to get a good understanding of interannual variability, and to keep a finger on the pulse of the shrinking ice sheet. It won’t be long before we’ll be able to use simple computer modeling to estimate future melt in different atmospheric warming scenarios. Then we’ll know better how much this large ice-covered region can contribute to sea level rise. And as a scientific community we’ll have more evidence to share with policy makers, so that they can take action to further combat climate change.
About the Author: Dirk van As (45) studied meteorology and physical oceanography in Utrecht, The Netherlands. He focussed on the Antarctic ice sheet as a PhD student before turning his attention to the Greenland ice sheet in 2007 as a senior researcher at the Geological Survey of Denmark and Greenland. Here he helped design and build a large measurement network monitoring the ice sheet. In 2018 Dirk started his own science and logistics support company Greenland Guidance. Dirk is an outspoken advocate of the need to reverse human-induced climate change, urging governments to act on scientific evidence and without further delay.
Related: Greenland Glacier Climate Research Sponsored By FORLOH, FORLOH On Climate Change