Drones For Earth Weekend 2023: Mapping the Moiry glacier
Every year, the Drones4Earth team meets up for a mapping weekend. This is an occasion for all members to get familiar with new drones and maintain existing skills. We also take advantage of the occasion to map an interesting landmark, often to help out a research project. All the better if the terrain is tricky, we can test out new techniques and perfect existing ones.
In 2023, we went to Glacier de Moiry, in Valais. It is a beautiful valley glacier, in the top part of Val de Moiry, at an altitude of 2400 m AMSL (at terminus).
It’s not the first time Drones for Earth is on a glacier mapping mission, therefore it might be time to outline why glaciers are an important factor in our environment.
Glaciers play a pivotal role in our environment as:
- Freshwater Reservoirs: Glaciers store vast amounts of freshwater as ice, releasing meltwater gradually into rivers and streams, ensuring a steady water supply for ecosystems and human communities, particularly during dry seasons.
- Sea Level Regulators: Glaciers regulate sea levels by controlling the amount of water entering the oceans as they melt. Their gradual melt contributes to rising sea levels, which can have profound impacts on coastal regions worldwide.
- Climate Indicator: Glaciers are sensitive indicators of climate change. Their retreat or advance reflects shifts in temperature and precipitation patterns, providing scientists with valuable insights into long-term climate trends.
- Ecosystem Support: Glacial meltwater nourishes downstream ecosystems, supporting diverse habitats and biodiversity. Many plants and animals depend on glacial-fed rivers for their survival.
The study of these parameters are the tasks of glaciologists.
Glaciologists investigate various aspects of ice and its interactions with the surrounding environment, including the processes of ice formation, movement, and melting, as well as the broader impacts of glacial behavior on climate, sea level rise, and ecosystems. Their work involves field observations, data collection, laboratory analysis, and the use of various tools such as remote sensing technology, ice core sampling, and computer modeling to better understand the dynamic behavior of glaciers and their role within the Earth’s cryosphere and climate system.
This year Drones for Earth had the benefit to have a glaciologist on the team, Sebastian Vivero. He has been studying glaciers globally since more than a decade, including the use of aerial mapping drones to acquire high resolution datasets.
Mapping glaciers with drones results in stunningly detailed and high-resolution datasets that provide insights into the dynamic nature of these icy giants.
Accurate Topographical Mapping for change detection over time:
These drone-generated high-resolution images and elevation data enable glaciologists to create accurate and up-to-date topographical maps of glacier surfaces. By comparing these maps over time, researchers can identify changes in glacier extent, movement, and elevation, allowing them to track the glacier’s response to climate fluctuations and provide a better understanding of glacier dynamics.
Speed and direction of ice flow and dynamics:
Detailed drone imagery allows glaciologists to track the movement of individual ice features, such as crevasses, icebergs, and meltwater channels. By analyzing the speed and direction of ice flow, scientists can model the complex interactions between ice, water, and terrain. This information is crucial for predicting how glaciers will respond to different climate scenarios.
Volume and Mass Balance:
Glaciologists need accurate measurements of glacier volume and mass balance to assess their health and contributions to sea level rise. Drones equipped with sensors can gather data on ice thickness, which, when combined with surface elevation data, helps estimate the overall volume of ice. By monitoring changes in mass balance over time, scientists can gauge the impact of melting and accumulation.
Meltwater and Hydrology:
Drones also provide insights into the hydrology of glacier systems. By observing meltwater patterns and channels on the glacier’s surface, glaciologists can understand how meltwater moves through the glacier and contributes to downstream freshwater systems. This information is crucial for managing water resources in regions that rely on glacial meltwater.
Climate Change Indicators:
The data collected from drone surveys contributes to our understanding of climate change impacts. As glaciers are sensitive indicators of temperature and precipitation patterns, their behavior can provide information about broader climate trends. The observations made contribute to climate models and inform policy decisions.
Safety and Accessibility:
Drones are also instrumental in improving safety during glacial fieldwork. Traditional ground-based surveys can be hazardous due to crevasses and uneven terrain. Drones allow glaciologists to explore and analyze hard-to-reach areas without risking human lives, enhancing both safety and efficiency.
To create the digital 3D model of the Moiry glacier, we organized ourselves into two teams. The first team layed out the ground control points (GCPs) around the bottom part of the glacier. The second team hiked further up to reach a good take-off and landing spot, plus including a good viewpoint to maintain the drones in line of sight.
We had brought a Trinity F90+, an eBee X and a Phantom 4 RTK. While we wanted to compare the different outputs, we came to realize that a combination of the datasets would deliver the best results.
The terrain is very complex, which means a fixed-wing drone will struggle to maintain a regular GSD throughout the acquisition, while a copter drone achieves this more easily, but will take significantly longer to complete the entire area.
Having put down the ground control points, we started the drone data acquisition. Due to weather, we didn’t manage to finish the first day and had to continue the next day.
The teams gathered strengths during extensive BBQ at the campsite. our timing was perfect as we got to admire the Perseid meteor shower at its peak, without interference from the moon. The shooting stars were so bright they lit up the valley!
On the second day we continued our mission. In total we collected over 1500 images, covering about 160 hectares within about 120 min of flight time.
Click the link below to see the 3D Model of glacier Moiry after processing with the photogrammetry software Agisoft Metashape: https://sketchfab.com/models/70622ec6dd4047a985e5c941e9728006
In conclusion, the rich datasets generated by these missions empower glaciologists to study glaciers in unprecedented detail, leading to enhanced understanding of glacier behavior, the impacts of climate change, and the broader implications for global ecosystems and sea levels. As technology continues to advance, drone-based mapping promises to further expand our knowledge of these vital components of our planet’s cryosphere.
Thank you to our supporters Quantum-Systems, Agisoft Metashape, AgEagle and UNIL.
