Soil temperature and soil water content measurements near Umiujaq and in the Sheldrake catchment

In northern regions, the seasonal Freeze Thaw (FT) is among climatic phenomenon having major impacts on terrestrial photosynthesis and respiration as well as soil evaporation and water percolation into the underground soil layers. From 2011 onwards, a study was led by the Research team in Environmental and Northern Remote Sensing (TENOR) of the Institut national de la recherche scientifique (INRS), in association with Centre for Northern Studies (CEN) and the Ludwig-Maximilians University (LMU) in Germany. The FT status of the soil is monitored with space-born satellite images (SMOS, SMAP, ALOS-PALSAR, TerraSAR-X, and Sentinel-1) by applying algorithms to detect the freezing on set and offset date of the soil. Further, Interferometric SAR technics (InSAR) are applied to monitor the vertical motion of the ground caused by permafrost degradation. To validate the results, probes were installed near the soil surface (in the first 15 centimeters) near the village of Umiujaq, located in Nunavik along the Hudson Bay coast. This subarctic region was chosen as many scientific studies linked to permafrost monitoring has been done by the Center of Northern Studies scientists. Then, hourly soil temperature and soil water content are recorded since September 26, 2011 at different locations around the Umiujaq village and at the Sheldrake watershed.