Day 4

Detailed paper information

Back to list

Paper title Zero isochion in Czechia derived by using Sentinel-2 data
  1. Ondrej Ledvinka Czech Hydrometeorological Institute Speaker
  2. Vit Stovicek Czech Hydrometeorological Institute
Form of presentation Poster
  • A7. Hydrology and Water Cycle
    • A7.01 Inland Water Storage and Runoff: Modeling, In Situ Data and Remote Sensing
Abstract text Operational hydrologists in Czechia often need information on the position of the zero isochion (otherwise known as snow line) in order to correctly delineate the snow-covered area in geomorphological regions. This activity is extremely helpful when determining the information on water stored in snow during the winter season, which, in turn, helps the Czech hydrologists properly model the expected runoff or to better quantify the individual components of water balance. So far, the estimation of the spatial distribution of snow cover and snow water equivalent has been performed through spatial interpolation which is supposed not to estimate the positive values below the zero isochion, the altitude of which is calculated once a week using the combination of in-situ data collected by the Czech Hydrometeorological Institute and remotely sensed data coming from the MODIS imagery. The advantage of the MODIS products is the time resolution, while their disadvantage is the resolution in the space domain (i.e. pixel of the edge of 500 m). This disadvantage often plays a role in discriminating between various classes of the landscape and often prevents the recognition of the snow-covered areas in forests. Therefore, the purpose of this contribution is to experimentally employ another satellite product here, which has a finer spatial resolution, that is the COPERNICUS Sentinel-2 data. The R package 'sen2r' was used to download the Sentinel-2 images and also to further process the data to get the Normalized Difference Snow Index, based on which the discrimination between the snow-covered areas and the areas without snow was carried out for the territory of Czechia (or at least its selected regions) and for the winter season defined by the months of November through May. The task is to find out if the Sentinel-2 data can be routinely used instead of the MODIS data when defining the position of the zero isochion in Czechia. The by-product of the analyses might be the substitution of the commercial processing software by the selected open source software.