Arctic lake classification from NASA ABoVE digital color infrared airborne imagery

Ethan Kyzivat, Brown University, ethan_kyzivat@brown.edu (Presenter)
Laurence C Smith, UCLA, lsmith@geog.ucla.edu
Sarah Cooley, Brown University, cooleysarahw@gmail.com
Lincoln H Pitcher, UCLA, lincolnpitcher@g.ucla.edu
John Arvesen, Cirrus Digital Systems, arvesen@cirrus-designs.com
Tamlin M Pavelsky, University of North Carolina Chapel Hill, pavelsky@unc.edu

One of the novel sensors deployed in ABoVE field compaings is AirSWOT, which aims to map surface water elevations in lake, wetland and river environments. The AirSWOT instrument suite includes a Ka-band experimental interferometric synthetic aperture radar and a NASA color infrared (CIR) Digital Camera System (DCS). In July and August 2017, NASA AirSWOT flew from southern Canada to Arctic Alaska, mapping >3,000 km² area including hundreds of lakes underlain by spatially varying geologic and permafrost conditions. This research aims to statistically assess the spatial variability of lake size and elevation changes to determine their sensitivity to broad-scale environmental gradients. To this end, we mapped lakes from 1 m spatial resolution, 16-bit, multiband, CIR orthomosaics. We classified water boundaries using a probabilistic adaptive thresholding technique applied to a normalized difference water index (NDWI). Next, we validated the derived lake water mask using in-situ shoreline maps collected with GPS. Results will identify spatial variability in lake size, distribution and quality across ~20 deg. of latitude. The resulting water mask will also assist in validation of the coincident radar interferometry data. Our findings should enhance the understanding of changing Arctic hydrologic systems and associated landscape controls on surface water variability.

Associated Project(s): 

• Smith-L-01

Poster Location ID: 99

Session Assigned: Permafrost and Hydrology