Dynamic variations in thermal regime and surface deformation along the drainage channel for an expanding lake on the Tibetan Plateau

ABSTRACT

The outburst of Zonag Lake in 2011 triggered a series of floods in the continuous permafrost region of the hinterland of the Qinghai-Tibet Plateau. This re-distributed the surface water in the basin and caused rapid expansion of the tail lake (Salt Lake). To avoid potential overflow of the expanding Salt Lake, a channel was excavated to drain the lake water into a downstream river. In this study, to investigate the permafrost thermal regime and the surface deformation around the expanding Salt Lake and the channel, in-situ monitoring sections were settled from Salt Lake to the downstream of the channel to obtain the permafrost temperature. Additionally, using small baseline subset interferometric synthetic aperture radar (SBAS-InSAR), the surface deformation around Salt Lake and the channel was measured. The data showed that the ground temperature at the channel was 0.6°C higher than the natural field and the mean subsidence rate around the channel was 1.5 mm/yr higher than that at Salt Lake. These results show that the permafrost temperature in the study area changed considerably with variations in the distance from the lake/channel, and the deformation in the study area was dominated by subsidence.

KEYWORDS:

• Permafrost environment
• ground temperature
• SBAS-InSAR
• climate change

Acknowledgments

We are grateful to Alaska Satellite Facility (ASF), European Space Agency (ESA) data center and USGS for providing the datasets used in this study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The raw data used in this study are publicly available from the sources provided in following links. The processed data generated from this study are available upon request to the corresponding author.

• Sentinel-1A data: https://search.asf.alaska.edu/

• Precious orbit data: https://scihub.copernicus.eu/

• Landsat data and SRTM data: https://earthexplorer.usgs.gov/

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15481603.2023.2266661

Additional information

Funding

The work was funded by the Second Tibetan Plateau Scientific Expedition and Research (STEP) program [2019QZKK0905]; the Science and Technology Project of Gansu Province [22ZD6FA004]; the Strategic Priority Research Program of the Chinese Academy of Sciences [XDA19070504].