polar2018-talk.pdf (5.48 MB)
Exploiting digital imagery for snow surface retrieval on sea ice
We show how imagery from uncalibrated airborne cameras can be used to
reconstruct the snow/air interface on Antarctic sea ice, using data
collected on the SIPEX-II research voyage during austral spring 2012.
Imagery collected by an airborne surveying package was used to develop a
3D surface model using a structure-from-motion approach. This model was
validated using coincident airborne LiDAR and in situ observation of
total freeboard. Our study demonstrates that equivalent surveys may be
obtained using unmanned vehicles (drones) carrying only a camera and
basic navigation equipment. Using this method, detailed
floe-to-multifloe scale models of snow topography may be derived without
logistically intensive airborne surveying programs. In turn, this
allows for quick repeat surveys - simplifying the capture of a surface
topography time series at any given field research site. It also allows
for highly detailed analysis of relationships between surface features
and how the evolve over time. Finally, we show how different surveying
scenarios affect data quality and the ability to easily co-register
surface models with other coincident datasets. We discuss how future
surveys should be planned, which data need to be collected alongside the
imagery used to generate 3D models, and where future development should
be aimed at in terms of uncertainty computations and data quality
assessment.