Landscape freeze/thaw mapping from active and passive microwave Earth observations over the Tursujuq National Park, Quebec, Canada
- Author:
- Touati C., Ratsimbazafy T., Poulin J., Bernier M., Homayouni S. & Ludwig R.
- Year:
- 2021
- Journal:
- Écoscience
- Pages:
- 28(3): 421–433
- Url:
- https://doi.org/10.1080/11956860.2021.1969790
We investigated the sensitivity to vegetation cover type of active (PALSAR) and passive (SMAP)
freeze/thaw (F/T) classification. We also used F/T classification from high-resolution PALSAR data
(30 m) to follow the evolution of frozen and thawed soil states obtained from an adaptive
algorithm with low-resolution SMAP data (36 km). We used PALSAR and SMAP scenes acquired
from June 2015 to January 2017 over the Tursujuq National Park (Umiujaq, Quebec, Canada). A new
F/T algorithm with a specific reference threshold under each vegetation type (shrub, grass, lichen,
wetland, and bare land) is proposed to classify PALSAR pixels. The validation of the PALSAR F/T
classification with soil temperature at ~5 cm depth revealed a greater overall accuracy (> 80%),
with horizontal transmitted and vertical received (HV) thresholds. The PALSAR F/T classification
shows that a SMAP pixel is classified as frozen when more than 50% of its area is frozen at the
surface. We confirmed the sensitivity to vegetation cover type of passive and active F/T classification
with L-band sensor.
Keywords: PALSAR; SMAP; vegetation; freeze/thaw algorithms; Nunavik.
- Id:
- 34021
- Submitter:
- zdenek
- Post_time:
- Sunday, 02 January 2022 15:47

