{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T10:19:57Z","timestamp":1760523597424,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T00:00:00Z","timestamp":1521072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>We present ground deformations in response to water level variations at the Toktogul Reservoir, located in Kyrgyzstan, Central Asia. Ground deformations were measured by Envisat Advanced Synthetic Aperture Radar (ASAR) and Sentinel-1 Differential Interferometric Synthetic Aperture Radar (DInSAR) imagery covering the time periods 2004\u20132009 and 2014\u20132016, respectively. The net reservoir water level, as measured by satellite radar altimetry, decreased approximately 60 m (\u223c13.5 km3) from 2004\u20132009, whereas, for 2014\u20132016, the net water level increased by approximately 51 m (\u223c11.2 km3). The individual Small BAseline Subset (SBAS) interferograms were heavily influenced by atmospheric effects that needed to be minimized prior to the time-series analysis. We tested several approaches including corrections based on global numerical weather model data, such as the European Centre for Medium-RangeWeather Forecasts (ECMWF) operational forecast data, the ERA-5 reanalysis, and the ERA-Interim reanalysis, as well as phase-based methods, such as calculating a simple linear dependency on the elevation or the more sophisticated power-law approach. Our findings suggest that, for the high-mountain Toktogul area, the power-law correction performs the best. Envisat descending time series for the period of water recession reveal mean line-of-sight (LOS) uplift rates of 7.8 mm\/yr on the northern shore of the Toktogul Reservoir close to the Toktogul city area. For the same area, Sentinel-1 ascending and descending time series consistently show a subsidence behaviour due to the replenishing of the water reservoir, which includes intra-annual LOS variations on the order of 30mm. A decomposition of the LOS deformation rates of both Sentinel-1 orbits revealed mean vertical subsidence rates of 25 mm\/yr for the common time period of March 2015\u2013November 2016, which is in very good agreement with the results derived from elastic modelling based on the TEA12 Earth model.<\/jats:p>","DOI":"10.3390\/rs10030462","type":"journal-article","created":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T09:21:37Z","timestamp":1521105697000},"page":"462","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Ground Deformations around the Toktogul Reservoir, Kyrgyzstan, from Envisat ASAR and Sentinel-1 Data\u2014A Case Study about the Impact of Atmospheric Corrections on InSAR Time Series"],"prefix":"10.3390","volume":"10","author":[{"given":"Julia","family":"Neelmeijer","sequence":"first","affiliation":[{"name":"GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany"},{"name":"Institute of Photogrammetry and GeoInformation, Leibniz University Hannover, 30167 Hannover, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4118-9578","authenticated-orcid":false,"given":"Tilo","family":"Sch\u00f6ne","sequence":"additional","affiliation":[{"name":"GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany"}]},{"given":"Robert","family":"Dill","sequence":"additional","affiliation":[{"name":"GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8342-8947","authenticated-orcid":false,"given":"Volker","family":"Klemann","sequence":"additional","affiliation":[{"name":"GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany"}]},{"given":"Mahdi","family":"Motagh","sequence":"additional","affiliation":[{"name":"GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany"},{"name":"Institute of Photogrammetry and GeoInformation, Leibniz University Hannover, 30167 Hannover, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2025","DOI":"10.1785\/BSSA0780062025","article-title":"Two types of reservoir-induced seismicity","volume":"78","author":"Simpson","year":"1988","journal-title":"Bull. Seismol. Soc. Am."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"16341","DOI":"10.1029\/2000JB900079","article-title":"Reservoir-induced deformation and continental rheology in vicinity of Lake Mead, Nevada","volume":"105","author":"Kaufmann","year":"2000","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.pepi.2003.05.001","article-title":"Geodetic measurement of the local elastic response to the changing mass of water in Lago Laja, Chile","volume":"141","author":"Bevis","year":"2004","journal-title":"Phys. Earth Planet. Inter."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1795","DOI":"10.1002\/jgrb.50104","article-title":"The use of GPS horizontals for loading studies, with applications to northern California and southeast Greenland","volume":"118","author":"Wahr","year":"2013","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_5","first-page":"B03403","article-title":"Ground motion measurement in the Lake Mead area, Nevada, by differential synthetic aperture radar interferometry time series analysis: Probing the lithosphere rheological structure","volume":"112","author":"Doin","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"B05412","DOI":"10.1029\/2011JB008961","article-title":"Rising of the lowest place on Earth due to Dead Sea water-level drop: Evidence from SAR interferometry and GPS","volume":"117","author":"Nof","year":"2012","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1016\/j.epsl.2016.05.044","article-title":"InSAR observations of lake loading at Yangzhuoyong Lake, Tibet: Constraints on crustal elasticity","volume":"449","author":"Zhao","year":"2016","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"L14501","DOI":"10.1029\/2005GL023458","article-title":"Water level changes at an ice-dammed lake in west Greenland inferred from InSAR data","volume":"32","author":"Furuya","year":"2005","journal-title":"Geophys. Res. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5290","DOI":"10.1002\/2014JB011768","article-title":"InSAR measurement of the deformation around Siling Co Lake: Inferences on the lower crust viscosity in central Tibet","volume":"120","author":"Doin","year":"2015","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_10","first-page":"425","article-title":"InSAR and GPS measurements of crustal deformation due to seasonal loading of Tehri reservoir in Garhwal Himalaya, India","volume":"209","author":"Gahalaut","year":"2017","journal-title":"Geophys. J. Int."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1029\/JB086iB01p00345","article-title":"Tectonics and seismicity of the Toktogul Reservoir Region, Kirgizia, USSR","volume":"86","author":"Simpson","year":"1981","journal-title":"J. Geophys. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1016\/j.tecto.2015.06.020","article-title":"Tectonic and gravity-induced deformation along the active Talas\u2013Fergana Fault, Tien Shan, Kyrgyzstan","volume":"657","author":"Tibaldi","year":"2015","journal-title":"Tectonophysics"},{"key":"ref_13","unstructured":"Savoskul, O.S. (2003). Water, climate, food, and environment in the Syr Darya Basin. Contribution to the Project ADAPT, The Pennsylvania State University."},{"key":"ref_14","unstructured":"Keith, J.E., and McKinney, D.C. (2017, December 15). Options Analysis of the Operation of the Toktogul Reservoir. Available online: http:\/\/www.ce.utexas.edu\/prof\/mckinney\/papers\/aral\/Issue7.html."},{"key":"ref_15","unstructured":"(2017, March 10). Kyrgyzstan Disaster Risk Data Platform. Available online: http:\/\/geonode.mes.kg."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1785\/BSSA0870010023","article-title":"The MS = 7.3 1992 Suusamyr, Kyrgyzstan, Earthquake in the Tien Shan: 2. Aftershock Focal Mechanisms and Surface Deformation","volume":"87","author":"Ghose","year":"1997","journal-title":"Bull. Seismol. Soc. Am."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Dovgan, V. (2012, January 12\u201314). Seismometric Monitoring of Toktogul Hydroelectric Power Station. Proceedings of the IV International Conference \u201cProblems of Cybernetics and Informatics\u201d (PCI\u20192012), Baku, Azerbaijan.","DOI":"10.1109\/ICPCI.2012.6486348"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"7547","DOI":"10.1029\/96JB03804","article-title":"Atmospheric effects in interferometric synthetic aperture radar surface deformation and topographic maps","volume":"102","author":"Zebker","year":"1997","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"968","DOI":"10.1038\/nature04797","article-title":"Interseismic strain accumulation and the earthquake potential on the southern San Andreas fault system","volume":"441","author":"Fialko","year":"2006","journal-title":"Nature"},{"key":"ref_20","first-page":"B05419","article-title":"Tropospheric phase delay in interferometric synthetic aperture radar estimated from meteorological model and multispectral imagery","volume":"112","author":"Michel","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1345","DOI":"10.1002\/2014JB011558","article-title":"A spatially variable power law tropospheric correction technique for InSAR data","volume":"120","author":"Bekaert","year":"2015","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1029\/94EO00944","article-title":"Radar altimetry: A new concept in monitoring lake level changes","volume":"75","author":"Birkett","year":"1994","journal-title":"Eos Trans. Am. Geophys. Union"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1007\/s10712-016-9362-6","article-title":"Lake Volume Monitoring from Space","volume":"37","author":"Arsen","year":"2016","journal-title":"Surv. Geophys."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1007\/1345_2017_265","article-title":"Water in Central Asia: Reservoir Monitoring with Radar Altimetry Along the Naryn and Syr Darya Rivers","volume":"Volume 147","author":"Dusik","year":"2017","journal-title":"Proceedings of the International Symposium on Earth and Environmental Sciences for Future Generations"},{"key":"ref_25","unstructured":"CA WATER Info (2017, January 31). Available online: www.cawater-info.net."},{"key":"ref_26","unstructured":"(2017, January 31). JSC \u201cElectric Stations\u201d. Available online: www.energo-es.kg."},{"key":"ref_27","unstructured":"F\u00f6rste, C., Bruinsma, S., Abrykosov, O., Flechtner, F., Dahle, C., Neumayer, K.H., Barthelmes, F., K\u00f6nig, R., Marty, J.-C., and Lemoine, J.M. (2013, January 1\u20136). EIGEN-6C3\u2014The newest high resolution global combined gravity field model based on the 4th release of the GOCE Direct Approach. Proceedings of the 2013 IAG Scientific Assembly, 150th Anniversary of the IAG, Potsdam, Germany."},{"key":"ref_28","unstructured":"Werner, C.L., Wegm\u00fcller, U., Strozzi, T., and Wiesmann, A. (2000, January 16\u201320). GAMMA SAR and Interferometric Processing Software. Proceedings of the ERS-ENVISAT Symposium, Gothenburg, Sweden."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Prats, P., Marotti, L., Wollstadt, S., and Scheiber, R. (2010, January 25\u201330). Investigations on TOPS interferometry with TerraSAR-X. Proceedings of the 2010 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Honolulu, Hawaii.","DOI":"10.1109\/IGARSS.2010.5650037"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3179","DOI":"10.1109\/TGRS.2011.2178247","article-title":"TOPS Interferometry With TerraSAR-X","volume":"50","author":"Scheiber","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2179","DOI":"10.1109\/36.868876","article-title":"Coregistration of interferometric SAR images using spectral diversity","volume":"38","author":"Scheiber","year":"2000","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_32","first-page":"431","article-title":"Sentinel-1 IWS mode support in the GAMMA software","volume":"100","author":"Werner","year":"2016","journal-title":"Procedia Comput. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2375","DOI":"10.1109\/TGRS.2002.803792","article-title":"A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms","volume":"40","author":"Berardino","year":"2002","journal-title":"IEEE T. Geosci. Remote"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.tecto.2011.10.013","article-title":"Recent advances in SAR interferometry time series analysis for measuring crustal deformation","volume":"514\u2013517","author":"Hooper","year":"2012","journal-title":"Tectonophysics"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"L16302","DOI":"10.1029\/2008GL034654","article-title":"A multi-temporal InSAR method incorporating both persistent scatterer and small baseline approaches","volume":"35","author":"Hooper","year":"2008","journal-title":"Geophys. Res. Lett."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2737","DOI":"10.1364\/JOSAA.24.002737","article-title":"Phase unwrapping in three dimensions with application to InSAR time series","volume":"24","author":"Hooper","year":"2007","journal-title":"J. Opt. Soc. Am."},{"key":"ref_37","unstructured":"Marinkovi\u0107, P., and Larsen, Y. (2015, January 23\u201327). On Resolving the Local Oscillator Drift Induced Phase Ramps in ASAR and ERS1\/2 Interferometric Data\u2014The Final Solution. Proceedings of the Fringe 2015 workshop (ESA SP-731), Frascati, Italy."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1016\/j.rse.2015.08.035","article-title":"Statistical comparison of InSAR tropospheric correction techniques","volume":"170","author":"Bekaert","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.jappgeo.2009.03.010","article-title":"Corrections of stratified tropospheric delays in SAR interferometry: Validation with global atmospheric models","volume":"69","author":"Doin","year":"2009","journal-title":"J. Appl. Geophys."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2324","DOI":"10.1002\/2013JB010588","article-title":"Improving InSAR geodesy using Global Atmospheric Models","volume":"119","author":"Jolivet","year":"2014","journal-title":"J. Geophys. Res.-Solid Earth"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"4121","DOI":"10.1002\/ggge.20258","article-title":"Characterizing and estimating noise in InSAR and InSAR time series with MODIS","volume":"14","author":"Barnhart","year":"2013","journal-title":"Geochem. Geophys."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"L17311","DOI":"10.1029\/2011GL048757","article-title":"Systematic InSAR tropospheric phase delay corrections from global meteorological reanalysis data","volume":"38","author":"Jolivet","year":"2011","journal-title":"Geophys. Res. Lett."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1002\/qj.828","article-title":"The ERA-Interim reanalysis: Configuration and performance of the data assimilation system","volume":"137","author":"Dee","year":"2011","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"3063","DOI":"10.1029\/2001GL013174","article-title":"The complete (3-D) surface displacement field in the epicentral area of the 1999 M W 7.1 Hector Mine Earthquake, California, from space geodetic observations","volume":"28","author":"Fialko","year":"2001","journal-title":"Geophys. Res. Lett."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1016\/j.enggeo.2017.01.011","article-title":"Quantifying groundwater exploitation induced subsidence in the Rafsanjan plain, southeastern Iran, using InSAR time-series and in situ measurements","volume":"218","author":"Motagh","year":"2017","journal-title":"Eng. Geol."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"761","DOI":"10.1029\/RG010i003p00761","article-title":"Deformation of the Earth by surface loads","volume":"10","author":"Farrell","year":"1972","journal-title":"Rev. Geophys."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.jog.2015.04.005","article-title":"Applying local Green\u2019s functions to study the influence of the crustal structure on hydrological loading displacements","volume":"88","author":"Dill","year":"2015","journal-title":"J. Geodyn."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/0031-9201(81)90046-7","article-title":"Preliminary reference Earth model","volume":"25","author":"Dziewonski","year":"1981","journal-title":"Phys. Earth Planet. Inter."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"Q09001","DOI":"10.1029\/2012GC004162","article-title":"The effective elastic thickness of the continental lithosphere: Comparison between rheological and inverse approaches","volume":"13","author":"Tesauro","year":"2012","journal-title":"Geochem. Geophys. Geosys."},{"key":"ref_50","first-page":"1","article-title":"Evaluation of ECMWF forecasts, including 2014\u20132015 upgrades","volume":"Volume 765","author":"Haiden","year":"2015","journal-title":"ECMWF Technical Memoranda"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1186\/s40677-015-0021-x","article-title":"The Kambarata 2 blast-fill dam, Kyrgyz Republic: Blast event, geophysical monitoring and dam structure modelling","volume":"2","author":"Havenith","year":"2015","journal-title":"Geoenviron. Disasters"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1023\/A:1023559932255","article-title":"Probabilistic PGA and Arias Intensity maps of Kyrgyzstan (Central Asia)","volume":"7","author":"Abdrakhmatov","year":"2003","journal-title":"J. Seismol."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1016\/j.soildyn.2012.01.016","article-title":"Seismic hazard assessment in Central Asia: Outcomes from a site approach","volume":"37","author":"Bindi","year":"2012","journal-title":"Soil Dyn. Earthq. Eng."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/10\/3\/462\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T14:57:13Z","timestamp":1760194633000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/10\/3\/462"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,3,15]]},"references-count":53,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2018,3]]}},"alternative-id":["rs10030462"],"URL":"https:\/\/doi.org\/10.3390\/rs10030462","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2018,3,15]]}}}