Abstract:
Glacial runoff and suspended sediment transport
characteristics of the Chhota Shigri glacier were
studied during the whole ablation period (May–October
2010). Discharge patterns of this glacier show that August
experiences maximum runoff accounting for 34.2 % of the
total runoff, followed by July 32.9 %, June 14.3 %,
September 12.5 %, May 5.2 % and October 0.9 %. During
the study period, the maximum runoff (Qmax) was observed
in the evening (4–6 p.m.), whereas minimum runoff (Qmin)
was observed in the morning (7–9 a.m.). The lag time
between generation of meltwater from the glacier and its
emergence as runoff varied from 1 to 4 h depending on the
condition of melting during the melt season. A good correlation
(r2 = 0.71) was found between daily mean glacierspecific
runoff and air temperature of the study area. Daily
mean concentrations of suspended sediment for May, June,
July, August, September and October were found as 155,
506, 577, 591, 80.9 and 30.8 mg l-1, respectively, showing
maximum concentration of suspended sediment in August,
followed by July. Suspended sediment load also follows a
similar trend. Diurnal variations in the concentration of
suspended sediment of the investigation area are directly
associated with diurnal variations in meltwater runoff.
There is a strong relationship between concentration of
suspended sediment and discharge (r2 = 0.79) and suspended
sediment load with discharge (r2 = 0.94). The
average sediment yield of the Chhota Shigri glacier basin
was computed as 1689 t km-2 year-1 during the melt
season, much higher than the worldwide and Indian
averages.
