North Cascades National Park Complex glacier mass balance monitoring annual report, water year 2011: North Coast and Cascades Network
Riedel J and Larrabee M. 2013. North Cascades National Park Complex glacier mass balance monitoring annual report, water year 2011: North Coast and Cascades Network. Natural Resource Data Series. NPS/NCCN/NRDS—2013/483. National Park Service. Fort Collins, Colorado
Glaciers cover approximately 109 km2 in North Cascades National Park Service Complex (NOCA), and are a high-priority Vital Sign in the North Coast and Cascades Network (NCCN) monitoring plan because they are sensitive, dramatic indicators of climate change and drivers of aquatic and terrestrial ecosystems (Reidel et al. 2008). Since 1993, seasonal volume changes at four NOCA glaciers have been monitored using methods developed as part of the NCCN Glacier Monitoring Protocol (Reidel et al, 2008). During water year (WY) 2011, winter accumulation was above average for all glaciers. Winter mass balance ranged from 2.40 (±0.31) to 4.05 (±0.30) m water equivalent (w.e.). Summer melting was below average for all four glaciers, ranging from 70-84 percent of average. Summer balance ranged from -1.68 (±0.23) m w.e. to -2.82 (±0.32) m w.e. At Silver Glacier, recorded summer melt was the second lowest since monitoring began in 1993. Net mass balances in WY 2011 were positive for all four glaciers, the second consecutive year with positive balances recorded. At Noisy Glacier, net balance was the second largest since 1993. Net mass balances ranged from 0.37 (±0.42) to 1.24 (±0.32) m w.e. Equilibrium line altitudes ranged from 1620 to 2030 m; between 157 to 338 m below the 1993-2011 average. Positive mass balances observed in WY 2011 resulted in minor increases to the cumulative mass balance; doing little to offset significant losses observed during the past half century. Since 1993, the cumulative balance for the four monitored glaciers is between -10.84 m w.e. and -7.34 m w.e. Below average summer melt led to below average relative glacial contribution to streamflow at NOCA. Four major watershed glaciers contributed 311M m3of water to park lakes and streams. In Thunder Creek, glaciers provided about 22% of total summer runoff, whereas in the more arid, less glaciated Ross Lake basin, glaciers contributed less than 3% due to the heavy winter snowpack and low summer melt rates.
- Type
- Published Report
- Authors
- Riedel, Jon; Larrabee, Michael
- Date of Issue
- 2013-05
- Publisher
- National Park Service
- Units
- NOCA , NRSS
- Keywords
- ablation, Aerial, annual report, Area, bulk density, climate change, Discharge, ELA, equilibrium line altitude, firn, Geology, Glacier, Glacier monitoring, Habitat, Hydrology, Ice, Mass Balance, mean water equivalent, Meltwater, Monitoring, Natural Resource Conservation Service, Noisy Glacier, North Klawatti Glacier, oblique, Photograph, PWR-toolkit, Sandalee Glacier, Silver Glacier, snotel, snow depth, stake, Stream Flow, surface elevation, U.S. Geological Survey, Water Year
- Subjects
- Ecological Framework: Air and Climate | Weather and Climate | Weather and Climate , Ecological Framework: Geology and Soils | Geomorphology | Glacial Features and Processes , Ecological Framework: Water | Hydrology | Surface Water Dynamics