HR: 0800h
AN: H41D-0769 [Abstracts]
TI: Quantifying River Morphology in Arctic Streams: Remote Sensing and Field Based Measurement of Fluvial Response to Climate Change in Northern Alaska
AU: * Crosby, B T
EM: crosbenj@isu.edu
AF: Idaho State University, 921 S 8th Ave, Stop 8072, Pocatello, ID 83209,
AU: Olson, N F
EM: nfolson@gmail.com
AF: Idaho State University, 921 S 8th Ave, Stop 8072, Pocatello, ID 83209,
AB:
Though hydraulic geometry in temperate regions has been extensively studied, the remote nature of Arctic rivers
has inhibited their characterization. As modern warming progressively impacts arctic hillslope stability, hydrology
and network density, it becomes imperative to establish an empirical and mechanistic understanding of the
factors that shape northern streams. Toward these ends, we employ DEM analysis (60m and 5m cellsize),
satellite (ASTER) and aerial imagery as well as extensive field observations to characterize the form and function
of Arctic rivers and their drainage networks. Field and remotely sensed measurements of bed state, discharge,
slope, width and drainage area are used to establish scaling relationships that can be compared to channels of
similar morphology in temperate regions. Parameters from arctic rivers that are comparable to their temperate
equivalents shed light onto which aspects of channel form are insensitive to bed-fast ice, permafrost dominated
banks and extreme spring thaw events. Those channel parameters that are unique to the Arctic highlight the
aspects of that system that are most susceptible to change. Our measurements, which range over 5 orders of
magnitude in drainage area, also establish baseline conditions to which future changes in arctic river geometry
can be compared. Changes in arctic river geometry influence not only the chemical, biological and hydrologic
components of the Arctic system but also impact native subsistence hunting practices and the logistics of
resource extraction.
DE: 0744 Rivers (0483, 1856)
DE: 1825 Geomorphology: fluvial (1625)
DE: 1839 Hydrologic scaling
SC: Hydrology [H]
MN: 2007 Fall Meeting