SCALE SPATIAL VARIABILITY
; WIND-INDUCED LOSS
; CLIMATE-CHANGE
; GLACIER MELT
; PRECIPITATION GAUGE
; RUNOFF
; COVER
; MODEL
; DENSITY
; DEPTH
WOS学科分类:
Geosciences, Multidisciplinary
WOS研究方向:
Geology
英文摘要:
Seasonal snow is an important component of the Himalayan hydrological system, but a lack of observations at high altitude hampers understanding and forecasting of water availability in this region. Here, we use a passive gamma ray sensor that measures snow water equivalent (SWE) and complementary meteorological instruments installed at 4962 m a.s.l. in the Nepal Himalayas to quantify the evolution of SWE and snow depth over a 2-year period. We assess the accuracy, spatial representativeness and the applicability of the SWE and snow depth measurements using time-lapse camera imagery and field observations. The instrument setup performs well for snowpacks >50 mm SWE, but caution must be applied when interpreting measurements from discontinuous, patchy snow cover or those that contain lenses of refrozen meltwater. Over their typical similar to 6-month lifetime, snowpacks in this setting can attain up to 200 mm SWE, of which 10-15% consists of mixed precipitation and rain-on-snow events. Precipitation gauges significantly underrepresent the solid fraction of precipitation received at this elevation by almost 40% compared to the gamma ray sensor. The application of sub-daily time-lapse camera imagery can help to correctly interpret and increase the reliability and representativeness of snowfall measurements. Our monitoring approach provides high quality, continuous, near-real time information that is essential to develop snow models in this data scarce region. We recommend that a similar instrument setup be extended into remote Himalayan environments to facilitate widespread snowpack monitoring and further our understanding of the high-altitude water cycle.
1.Int Ctr Integrated Mt Dev, Kathmandu, Nepal 2.Univ Cambridge, Scott Polar Res Inst, Cambridge, England 3.British Antarctic Survey, Nat Environm Res Council, Cambridge, England 4.Norwegian Water Resources & Energy Directorate, Oslo, Norway 5.Univ Utrecht, Dept Phys Geog, Utrecht, Netherlands
Recommended Citation:
Kirkham, James D.,Koch, Inka,Saloranta, Tuomo M.,et al. Near Real-Time Measurement of Snow Water Equivalent in the Nepal Himalayas[J]. FRONTIERS IN EARTH SCIENCE,2019-01-01,7