Quantitative Step-loading Block Test: A Substitute for Loaded-column Test

A new snowpack stability test, quantitative step-loading block test (QSLBT) has beendeveloped and used operationally by the Snow and Avalanche Study Establishment during thewinter 2004-05 at Patsio Research Station in Great Himalayan range. This test is simple, takesless time in measurement, and effectively communicates the results. In this test, an isolated snowcolumn of area 13 cm x 18 cm (0.234 m2 or may be up to 0.30 m2) is cut out of the wall of a snowpit. A wooden block of known weight (0.21 kg) and of the dimension 13 cm x 18 cm is placedover the snow block and loaded in steps with iron weights of known quantity. On loading if theblock fails, the height of failure from ground and the load by which the failure of block has takenplace, are noted. While most of the stability tests in snow provide just an estimate of snowpackinstability, this test provides the quantity of load required to fail the snowpack. More than 40tests were carried out in Great Himalayan range during the winter 2004-05 and were comparedwith the shear strength of the failure plane. The results are in good agreement with shear frametest

Quantitative Step-loading Block Test: A Substitute for Loaded-column Test

A new snowpack stability test, quantitative step-loading block test (QSLBT) has beendeveloped and used operationally by the Snow and Avalanche Study Establishment during thewinter 2004-05 at Patsio Research Station in Great Himalayan range. This test is simple, takesless time in measurement, and effectively communicates the results. In this test, an isolated snowcolumn of area 13 cm x 18 cm (0.234 m2 or may be up to 0.30 m2) is cut out of the wall of a snowpit. A wooden block of known weight (0.21 kg) and of the dimension 13 cm x 18 cm is placedover the snow block and loaded in steps with iron weights of known quantity. On loading if theblock fails, the height of failure from ground and the load by which the failure of block has takenplace, are noted. While most of the stability tests in snow provide just an estimate of snowpackinstability, this test provides the quantity of load required to fail the snowpack. More than 40tests were carried out in Great Himalayan range during the winter 2004-05 and were comparedwith the shear strength of the failure plane. The results are in good agreement with shear frametest

A simple model for estimation of snow/ice surface temperature of Antarctic ice sheet using remotely sensed thermal band data

51-55In this paper, a model has been developed to estimate surface temperature of Antarctic ice sheet using thermal bands of Moderate Resolution Imaging Spectroradiometer (MODIS) sensor images and in situ surface temperature measurements. The brightness temperature of snow/ice surface of Antarctica has been estimated for MODIS bands 31 and 32 using Planck’s spectral radiation equation. Split window technique has been used to develop the model from brightness temperature and Automatic Weather Station recorded surface temperature. The model has been validated using in situ measurements of surface temperature of the ice sheet near Indian Antarctic Research Station ‘Maitri’. High coefficient of determination (R2 in the range 0.952 - 0.99) and low root mean square error (0.8 - 1.2°C) has been obtained between modeled and in situ recorded surface temperature. The model is easy to use and can generate the surface temperature maps at spatial resolution of 1.0 km. These maps can be useful in various glaciological, hydrological, climatological and ecological studies of the ice sheet