Snow Cover Area Estimation Using Radar and Optical Satellite Information

Abstract

Obtaining the seasonal variation of snow cover in areas of the Argentinian Andes is important for hydrological studies and can facilitate proper planning of water resources, with regard to irrigation, supply, flood attenuation and hydroelectricity. Remote sensors that work in the visible and infrared wavelength range are operational tools for monitoring the snow in clear skies. However, microwave satellites are able to obtain data regardless of atmospheric conditions. The advantage of using radar images is that they are very useful to obtain highly accurate parameters such as snow moisture depth, density and water equivalent resulting in improved forecasting models. In this paper, we analyze an ERS-2 image of the Andes mountain range in the northern region of the Neuquén province, Patagonia, Argentina. The objective was to obtain the spatial distribution of wet and dry snow and to compare these results with data from optical sensors (LANDSAT) in order to understand the topographic variables that influence the spatial distribution of wet snow. Optical information from sensors like LANDSAT TM 5 was analyzed to obtain fractional and binary snow indexes during a passage simultaneously with radar data. Surface temperature is used to study the association between the different types of snow altitudinal ranges and surface temperature. In this paper, we selected a scene on October 8th 2005. The entire methodology was systematized in a code implemented in IDL language.

Remote Sensing of Snow Cover Using Spaceborne SAR: A Review

“…The first one is based on volume water content (VWC), i.e., a snowpack with VWC above 1% is considered wet snow, while snow below 1% VWC is referred to as dry snow [84]. The second definition, which is used more often, is connected to the temperature of the snowpack: At temperatures below 0 • C the snowpack is presumed to remain dry while above 0 • C the snow is considered wet [35,85,86]. The temperature definition was validated by statistical analysis of wet snow temperatures and proven advantageous when compared to the VWC approach, as measurements of temperature are easier to obtain than of VWC [85].…”

“…Another approach is utilizing spaceborne thermal imagery. Salcedo and Cogliati [85] used atmospheric profiles of temperature and water vapor at the sensed time to derive the surface temperature based on recorded satellite radiance. Moreover, snow record data also helps to analyze the snow cover conditions.…”

Ground-Based Oblique-View Photogrammetry and Sentinel-1 Spaceborne RADAR Reflectivity Snow Melt Processes Assessment on an Arctic Glacier

“…In this paper, we highlight the combined use of freely accessible spaceborne C-band RADAR data and in situ optical digital pictures for the observation and the quantification of snowpack melting processes on a glacier surface, in line with past work, emphasizing the complementarity of optical and active microwave measurements [28][29][30]. We start by introducing the automated digital camera network we deployed a decade ago for the systematic imaging of the glacier basin.…”

An Integrated Shadow-Adjusted Snow-Aging Index for Alpine Regions

“…Surface features can produce scattering signals that increase uncertainties [44]. The bias in microwave radiation and scattering signals is caused by snow heterogeneity [45], scale inconsistency, and mixed pixel interference needs consideration by combining the optical and microwave data [46,47]. For these reasons, we prefer the use of optical data in the present work.…”