Results 251 to 260 of about 630,827 (291)

Retrieval of wet snow by means of multitemporal SAR data

IEEE Transactions on Geoscience and Remote Sensing, 2000
An algorithm has been developed for mapping wet snow in mountainous terrain using repeat pass synthetic aperture radar (SAR) images. As a basis for algorithm development, backscattering properties of snow-free and snow-covered alpine surfaces were investigated using ERS SAR data and field measurements at test sites in the Austrian Alps.
Thomas Nagler, H Rott
exaly   +2 more sources

Estimation of wet snow accretion on structures

Cold Regions Science and Technology, 1989
The criteria for the occurrence of wet snow accretion are discussed and it is pointed out that the beginning and duration of a wet snow incident can be determined using precipitation code, air temperature and humidity data. A simple operational model for estimating wet snow loads on overhead power lines is proposed. The model can be used in mapping the
Makkonen, Lasse
openaire   +3 more sources

Water movement in wet snow

Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 1996
A model is presented to describe the motion of the two-component water and air mixture in wet snow. The model takes into account the difference in velocities and pressures of mobile water, bound water, the ice and the air. An asymptotic form of this system of equations is used to investigate the percolation problem.
openaire   +4 more sources

Estimation of snow wetness by a dual-frequency radar

2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2017
In hydrological investigation, the liquid water content in snow pack is required which is important for modeling and forecasting snow melt runoff. Active microwave remote sensing has the potential of estimating snow parameters. In this study, we estimates snow wetness based on quasi-crystalline approximation — dense media radiative transfer (QCA-DMRT ...
Yurong Cui, Chuan Xiong, Jiancheng Shi 0001   +2 more
openaire   +2 more sources

Grain clusters in wet snow

Journal of Colloid and Interface Science, 1979
Abstract The grain boundaries in snow are generally unstable when the pore space is filled with liquid water (i.e., liquid-saturated snow. Thus, when unstressed snow is saturated with the melt, the ice particles in snow are cohesionless spheres. This leads to very low strengths and to rapid grain growth due to heat flow among particles of different ...
openaire   +1 more source

On dielectric properties of dry and wet snow

Hydrological Processes, 1999
The different sets of experimental data on dielectric permittivity of dry and wet snow at high frequencies have been approximated by various functions. In this paper we show a possibility of approximations of these data as the functions of dry snow density and water content using the Looyenga's mixture formulae with error of about 2% These ...
Anatoly D. Frolov, Yury Ya. Macheret
openaire   +1 more source

Wet Precipitation: Rain and Snow

1997
The geographical distribution of precipitation on the globe is determined by the general atmospheric circulation and by local topography, particularly the locations of mountains and oceans. In general, for condensation and precipitation of water, there must be saturated water vapor in the air and air must cool down.
openaire   +1 more source

Snow Fork for Field Determination of the Density and Wetness Profiles of a Snow Pack

IEEE Transactions on Geoscience and Remote Sensing, 1986
A radiowave sensor (a snow fork) for determining the density and wetness profiles of a snow pack with a single measurement has been developed. The snow fork is based on the measurement of the dielectric properties (real and imaginary part) of snow around 1 GHz. Due to the open structure of the resonator the measurement is nondestructive.
Ari Sihvola, Martti Tiuri
openaire   +1 more source

PolSAR Wet Snow Mapping With Incidence Angle Information

IEEE Geoscience and Remote Sensing Letters, 2016
Polarimetric synthetic aperture radar is expected to distinguish wet snow from bare ground. However, since both of them show surface scattering, which is sensitive to incidence angle, it often fails in the distinction in mountainous areas. In this letter, we propose an adaptive distinction method using quaternion neural networks. In the ALOS-2 data, we
Naoto Usami, Arnab Muhuri, Avik Bhattacharya, Akira Hirose 0001   +3 more
openaire   +2 more sources

Microstructural resistance of snow following first wetting

Cold Regions Science and Technology, 2011
Abstract One of the main causes for the formation of wet snow avalanches is the decrease in strength following the introduction of liquid water. The influence of liquid water on initially dry snow was investigated in twelve field experiments in the Eastern Swiss Alps.
Techel, F., Pielmeier, C., Schneebeli, M.   +2 more
openaire   +2 more sources