Open AccessIdentification of thawed and frozen soil state in some Siberia regions by multi-temporal Sentinel 1 radar data in 2017-2018
Author(s) -
Н. В. Родионова
Publication year - 2019
Publication title -
ceur workshop proceedings
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.177
H-Index - 52
ISSN - 1613-0073
DOI - 10.18287/1613-0073-2019-2416-1-10
Subject(s) - topsoil , radar , environmental science , correlation coefficient , soil water , soil science , remote sensing , backscatter (email) , geology , meteorology , geography , mathematics , telecommunications , statistics , computer science , wireless
The paper deals with the identification of thawed/frozen soils in the topsoil layer forthree stations in Siberia: Salekhard, Tiksi and Norilsk by using Sentinel 1B C-band radar data for the period of 2017-2018. Determination of the frozen/thawed soil state is carried out in three ways: 1) by multi-temporal radar data on the basis of a significant in 3-5 dB difference in the backscatter coefficient 0 in the transition of freezing/thawing soil state, 2) by finding the threshold value of 0 at which the temperature in the topsoil layer falls below 00C, 3) by texture features. The first method allows determining the period of time during which the process of freezing/thawing of the soil occurs. The second and third methods allow making local maps of frozen/thawed soils. It is shown that for the studied areas the Spearman correlation coefficient between 0 and air temperature for cross - polarization exceeds the correlation coefficient for co-polarization. The graphs of the AFI (air freezing index) for the period of 2012-2018 are constructed based on the archive data of air temperature for the study areas.