Time-varying land subsidence detected by radar altimetry: California, Taiwan and north China

Scientific Reports
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Abstract

Contemporary applications of radar altimetry include sea-level rise, ocean circulation, marine gravity, and ice sheet elevation change. Unlike InSAR and GNSS, which are widely used to map surface deformation, altimetry is neither reliant on highly temporally-correlated ground features nor as limited by the available spatial coverage, and can provide long-term temporal subsidence monitoring capability. Here we use multi-mission radar altimetry with an approximately 23 year data-span to quantify land subsidence in cropland areas. Subsidence rates from TOPEX/POSEIDON, JASON-1, ENVISAT, and JASON-2 during 1992–2015 show time-varying trends with respect to displacement over time in California’s San Joaquin Valley and central Taiwan, possibly related to changes in land use, climatic conditions (drought) and regulatory measures affecting groundwater use. Near Hanford, California, subsidence rates reach 18 cm/yr with a cumulative subsidence of 206 cm, which potentially could adversely affect operations of the planned California High-Speed Rail. The maximum subsidence rate in central Taiwan is 8 cm/yr. Radar altimetry also reveals time-varying subsidence in the North China Plain consistent with the declines of groundwater storage and existing water infrastructure detected by the Gravity Recovery And Climate Experiment (GRACE) satellites, with rates reaching 20 cm/yr and cumulative subsidence as much as 155 cm.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Time-varying land subsidence detected by radar altimetry: California, Taiwan and north China
Series title Scientific Reports
DOI 10.1038/srep28160
Volume 6
Year Published 2016
Language English
Publisher Nature Publishing Group
Contributing office(s) Office of the AD Water, California Water Science Center, Ohio-Kentucky-Indiana Water Science Center
Description Article 28160; 12 p.
First page 1
Last page 12
Country China, Taiwan, United States
State California
Online Only (Y/N) N
Additional Online Files (Y/N) N