Characterized by vast amounts of carbon stored in permafrost and a rapidly evolving landscape, the Arctic is an important focal point for the study of climate change. These are sensitive systems, yet the mechanisms responsible for those sensitivities remain poorly understood and inadequately represented in Earth System Models. The NGEE Arctic project seeks to reduce uncertainty in climate prediction by better understanding critical land-atmosphere feedbacks in terrestrial ecosystems of Alaska.
Tuesday, July 16, 2013
Flying kites on the tundra
Scientists can be creative! A perfect example of this creativity reveals itself when the NGEE
Arctic project needs to collect aerial images of ice-rich polygons on the
Barrow Environmental Observatory. We could rely on high-resolution pictures
from aircraft, but given the small area of our intensive site that would be
expensive. Unfortunately, the resolution of satellite imagery is too coarse. Why not just hang a
camera from a kite? We saw this used quite effectively last year by Craig
Tweedie and his students from UTEP, so we thought we'd give it a try! That's what
Baptiste Dafflon and Craig Ulrich (both from LBNL) did yesterday after testing
the concept several weeks ago in California.
Baptiste and Craig have conducted geophysical surveys on
the BEO now for two years. The goal has been not only to understand sub-surface
properties like ice content and size and distribution of ice wedges, but also
to relate those characteristics to surface properties including topography and
the fraction of the landscape seasonally inundated by water. The team needed,
however, some way to correlate patterns of inundation to variation in
sub-surface properties. The kite seemed like a worthwhile approach to try. It
is too early to comment on the overall utility of the idea, but an initial look
at the aerial images suggests that the quality of pictures makes this
kite-based approach a reasonable one for our purposes.
Baptiste and Craig, along with others on the NGEE Arctic
team, plan to replace the camera with a spectrometer in hopes of using spectral
signatures to identify water distribution and landscape patterns of inundation
throughout the season. Then it will be possible to begin drawing correlations
between surface and subsurface characteristics and using those insights to
improve multi-scale models of terrestrial ecosystems.