Improving InSAR geodesy using global atmospheric models

Jolivet, R., Agram, P. S., Lin, N. Y., Simons, M., Doin, M.-P., Peltzer, G. and Li, Z. (2014) Improving InSAR geodesy using global atmospheric models. Journal of Geophysical Research: Solid Earth, 119(3), pp. 2324-2341. (doi: 10.1002/2013JB010588)

Abstract

Spatial and temporal variations of pressure, temperature and water vapor content in the atmosphere introduce significant confounding delays in Interferometric Synthetic Aperture Radar (InSAR) observations of ground deformation and bias estimatesof regional strain rates. Producing robust estimates of tropospheric delays remains one of the key challenges in increasing the accuracy of ground deformation measurements using InSAR. Recent studies revealed the efficiency of global atmospheric reanalysis to mitigate the impact of tropospheric delays, motivating further exploration of their potential. Here, we explore the effectiveness of these models in several geographic and tectonic settings on both single interferograms and time series analysis products. Both hydrostatic and wet contributions to the phase delay are important to account for. We validate these path delay corrections by comparing with estimates of vertically integrated atmospheric water vapor content derived from the passive multi-spectral imager MERIS, onboard the ENVISAT satellite. Generally, the performance of the prediction depends on the vigor of atmospheric turbulence. We discuss (1) how separating atmospheric and orbital contributions allows one to better measure long wavelength deformation, (2) how atmospheric delays affect measurements of surface deformation following earthquakes and (3) we show that such a method allows us to reduce biases in multi-year strain rate estimates by reducing the influence of unevenly sampled seasonal oscillations of the tropospheric delay.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Li, Dr Zhenhong
• Authors: Jolivet, R., Agram, P. S., Lin, N. Y., Simons, M., Doin, M.-P., Peltzer, G., and Li, Z.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Journal of Geophysical Research: Solid Earth
• Publisher: John Wiley & Sons Ltd.
• ISSN: 2169-9313
• ISSN (Online): 2169-9356
• Copyright Holders: Copyright © 2014 John Wiley and Sons Ltd.
• First Published: First published in Journal of Geophysical Research: Solid Earth 119(3):2324-2341
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher