Thermal Bird in the air over Canada Glacier in Taylor Valley. Photo: Eva Bendix Nielsen
Thermal bird survey of surface environments in the Taylor Valley
As part of our ecosystems research, the University of Canterbury has developed an infrared and visible camera system (a thermal bird) for aerial surveying of different Antarctic surface environments.
The McMurdo Dry Valleys in Antarctica’s Ross Sea region is a unique environment, with low humidity, and no snow or ice cover. Glacier runoff is the main source of liquid water in this hyper-arid desert. Yet these seemingly lifeless soils are home to a uniquely adapted suite of organisms, from bacteria to small invertebrates, that become metabolically active whenever conditions allow.
Our goal is to understand the functioning of the area’s fragile ecosystem and its vulnerability to environmental change. This requires investigation of the land temperature variability and microclimate, including the availability (spatially and over time) of meltwater. These variables can be observed year-round through remote satellite data and assessed using numerical hydroclimate models.
To validate these methods, an infrared and visible camera system - a thermal bird - was developed for aerial surveying of the different surface environments. The infrared Telops camera was first tested in the 2021/22 season, and learnings used to further develop a full system for data collection in 2022/23.
The thermal bird attached to the helicopter. Photo: Eva Bendix Nielsen
The camera system was mounted to a helicopter at Scott Base. In December and January 2023, airborne surveys were undertaken in the Taylor Valley in the McMurdo Dry Valleys, plus one scan along the coastline to Terra Nova Bay. Pre-defined flight tracks covered three different areas, chosen for their different surfaces and moisture content. The flights were timed to coincide with MODIS and Landsat satellite overpasses, and flew over a network of pre-deployed soil sensors, as well as ground control points and a base station for georeferencing (to enhance accuracy).
Spot the helicopter in this image! Visible imagery of Canada Glacier in Taylor Valley taken from the thermal bird. Photo: Eva Bendix Nielsen, Pete Wilson
Preliminary results. From left: Snapshot of visible and infrared imagery taken from the thermal bird during a survey of the soil in Taylor Valley. The dashed box indicates the extent of the infrared imagery. Right: The orthomosaic and digital elevation model of Commonwealth Glacier front in Taylor Valley. Photo: Eva Bendix Nielsen
This fieldwork was part of the Platform’s Ross Sea Ecosystems Project.
The data will be used to:
- validate a newly developed geostatistical downscaling model for land surface temperature in the unique environment of the McMurdo Dry Valleys;
- investigate bias in satellite derived land and ice surface temperature related to subpixel variations in surface types;
- validate WRF-Hydro/Glacier model performance in simulating spatially distributed conditions for melt and the routing of meltwater; and
- lay some of the groundwork for establishing a network of ecological “sentinel sites”, where the greatest environmental change is expected.
The research leader is Marwan Katurji. The field team was PhD student Eva Bendix Nielsen, and University of Canterbury technician Pete Wilson, who also did the development of the system. PhD Students Tamara Pletzer and Marte Hofsteenge were the on-ground team assisting with redeployment of the soil sensors, and PhD student Maite Lezama Valdes supported fieldwork planning.
Field team, Pete Wilson and Eva Bendix Nielsen in Taylor Valley. Photo: Eddie Pannett