{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,18]],"date-time":"2026-07-18T06:57:20Z","timestamp":1784357840228,"version":"3.55.0"},"reference-count":48,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2015,9,18]],"date-time":"2015-09-18T00:00:00Z","timestamp":1442534400000},"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 tested an off-ground ground-penetrating radar (GPR) system at a fixed location over a bare agricultural field to monitor the soil freeze-thaw cycles over a snow-covered surface. The GPR system consisted of a monostatic horn antenna combined with a vector network analyzer, providing an ultra-wideband stepped-frequency continuous-wave radar. An antenna calibration experiment was performed to filter antenna and back scattered effects from the raw GPR data. Near the GPR setup, sensors were installed in the soil to monitor the dynamics of soil temperature and dielectric permittivity at different depths. The soil permittivity was retrieved via inversion of time domain GPR data focused on the surface reflection. Significant effects of soil dynamics were observed in the time-lapse GPR, temperature and dielectric permittivity measurements. In particular, five freeze and thaw events were clearly detectable, indicating that the GPR signals respond to the contrast between the dielectric permittivity of frozen and thawed soil. The GPR-derived permittivity was in good agreement with sensor observations. Overall, the off-ground nature of the GPR system permits non-invasive time-lapse observation of the soil freeze-thaw dynamics without disturbing the structure of the snow cover. The proposed method shows promise for the real-time mapping and monitoring of the shallow frozen layer at the field scale.<\/jats:p>","DOI":"10.3390\/rs70912041","type":"journal-article","created":{"date-parts":[[2015,9,21]],"date-time":"2015-09-21T02:25:40Z","timestamp":1442802340000},"page":"12041-12056","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Temporal Monitoring of the Soil Freeze-Thaw Cycles over a Snow-Covered Surface by Using Air-Launched Ground-Penetrating Radar"],"prefix":"10.3390","volume":"7","author":[{"given":"Khan","family":"Jadoon","sequence":"first","affiliation":[{"name":"Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, 23955-6900 Thuwal, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lutz","family":"Weiherm\u00fcller","sequence":"additional","affiliation":[{"name":"Agrosphere (IBG-3), Forschungszentrum Jlich GmbH, 52425 Juelich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1279-5272","authenticated-orcid":false,"given":"Matthew","family":"McCabe","sequence":"additional","affiliation":[{"name":"Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, 23955-6900 Thuwal, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Davood","family":"Moghadas","sequence":"additional","affiliation":[{"name":"Federal Institute for Geosciences and Natural Resources (BGR), Stilleweg 2, 30655 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8051-8517","authenticated-orcid":false,"given":"Harry","family":"Vereecken","sequence":"additional","affiliation":[{"name":"Agrosphere (IBG-3), Forschungszentrum Jlich GmbH, 52425 Juelich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebast\u00eden","family":"Lambot","sequence":"additional","affiliation":[{"name":"Earth and Life Institute, Universite Catholique de Louvain, Croix du Sud, 2 box L7.05.02, Louvain-la-Neuve B-1348, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"763","DOI":"10.1029\/2000GL011952","article-title":"Soil freeze\/thaw cycles over snow-free land detected by passive microwave remote sensing","volume":"28","author":"Zhang","year":"2001","journal-title":"Geophys. Res. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2003JD003575","article-title":"Simulation of spatial variability in snow and frozen soil","volume":"108","author":"Cherkauer","year":"2003","journal-title":"J. Geophys. Res.-Atmos."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1843","DOI":"10.1002\/(SICI)1099-1085(199909)13:12\/13<1843::AID-HYP879>3.0.CO;2-G","article-title":"The effect of frozen soil on snowmelt runoff at Sleepers River, Vermont","volume":"13","author":"Shanley","year":"1999","journal-title":"Hydrol. Process."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.jhydrol.2013.01.032","article-title":"Spatial and temporal variability in seasonal snow density","volume":"484","author":"Bormann","year":"2013","journal-title":"J. Hydrol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"RG4002","DOI":"10.1029\/2004RG000157","article-title":"Influence of the seasonal snow cover on the ground thermal regime: An overview","volume":"43","author":"Zhang","year":"2005","journal-title":"Rev. Geophys."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"409","DOI":"10.4141\/CJSS09016","article-title":"Nitrous oxide fluxes related to soil freeze and thaw periods identified using heat pulse probes","volume":"90","author":"Rapai","year":"2010","journal-title":"Can. J. Soil Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1002\/ppp.471","article-title":"Snow cover and soil moisture controls on solifluction in an area of seasonal frost, eastern Alps","volume":"14","author":"Jaesche","year":"2003","journal-title":"Permaf. Periglac. Process."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.jhydrol.2004.11.012","article-title":"The influence of seasonally frozen soil on the snowmelt runoff at two Alpine sites in southern Switzerland","volume":"309","author":"Bayard","year":"2005","journal-title":"J. Hydrol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1080\/789610186","article-title":"Application of satellite remote sensing techniques to frozen ground studies","volume":"28","author":"Zhang","year":"2004","journal-title":"Polar Geogr."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1038\/nclimate2581","article-title":"Recent reversal in loss of global terrestrial biomass","volume":"5","author":"Liu","year":"2015","journal-title":"Nat. Clim. Change"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/0034-4257(94)90051-5","article-title":"Monitoring of environmental-conditions in taiga forests using ERS-1 SAR","volume":"49","author":"Rignot","year":"1994","journal-title":"Remote Sens. Environ."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1252","DOI":"10.1109\/TGRS.2004.825592","article-title":"Microwave L-band emission of freezing soil","volume":"42","author":"Schwank","year":"2004","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2813","DOI":"10.3390\/rs5062813","article-title":"Comparing two methods of surface change detection on an evolving thermokarst using high-temporal-frequency terrestrial laser scanning, Selawik River, Alaska","volume":"5","author":"Barnhart","year":"2013","journal-title":"Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"621","DOI":"10.3390\/rs6010621","article-title":"Temporal behavior of lake size-distribution in a thawing permafrost landscape in northwestern Siberia","volume":"6","author":"Karlsson","year":"2014","journal-title":"Remote Sens."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.2136\/vzj2013.04.0075","article-title":"Soil hydraulic parameters and surface soil moisture of a tilled bare soil plot inversely derived from L-band brightness temperatures","volume":"13","author":"Dimitrov","year":"2014","journal-title":"Vadose Zone J."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3206","DOI":"10.3390\/rs70303206","article-title":"Frozen soil detection based on advanced scatterometer observations and air temperature data as part of soil moisture retrieval","volume":"7","author":"Zwieback","year":"2015","journal-title":"Remote Sens."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1080\/01431161.2010.501830","article-title":"Detecting ice-sheet melt area over western Greenland using MODIS and AMSR-E data for the summer periods of 2002\u20132006","volume":"2","author":"McCabe","year":"2011","journal-title":"Remote Sens. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1109\/TGRS.2010.2070515","article-title":"Developing a global data record of daily landscape freeze\/thaw status using satellite passive microwave remote sensing","volume":"49","author":"Kim","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2004","DOI":"10.1109\/TGRS.2007.898436","article-title":"Satellite microwave remote sensing of boreal and arctic soil temperatures from AMSR-E","volume":"45","author":"Jones","year":"2007","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_20","unstructured":"Wilson, A. (2001, January 11\u201314). Progress and challenges in radar remote sensing of snow. Proceedings of the Third International Symposium on Retrieval of Bio- and Geophysical Parameters from Sar Data for Land Applications, Sheffield, UK."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1016\/j.rse.2014.03.007","article-title":"Detection of soil freezing from L-band passive microwave observations","volume":"147","author":"Rautiainen","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_22","unstructured":"Seungbum, K., Van Zyl, J., McDonald, K., and Njoku, E. (2010, January 10\u201314). Monitoring surface soil moisture and freeze-thaw state with the high-resolution radar of the Soil Moisture Active\/Passive (SMAP) mission. Proceedings of IEEE Radar Conference, Washington, DC, USA."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1002\/ppp.594","article-title":"Application of ground-penetrating radar imagery for three-dimensional visualisation of near-surface structures in ice-rich permafrost, Barrow, Alaska","volume":"18","author":"Munroe","year":"2007","journal-title":"Permafr. Periglac. Process."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/j.coldregions.2008.09.005","article-title":"Mapping subsurface conditions within the near-shore zone of an Arctic delta using ground penetrating radar","volume":"56","author":"Stevens","year":"2009","journal-title":"Cold Reg. Sci. Techno."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2022","DOI":"10.1002\/hyp.7688","article-title":"Field observations of shallow freeze and thaw processes using high-frequency ground-penetrating radar","volume":"24","author":"Steelman","year":"2010","journal-title":"Hydrol. Process."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"69","DOI":"10.2113\/JEEG12.1.69","article-title":"Applications of ground-penetrating radar to glacial and frozen materials","volume":"12","author":"Woodward","year":"2007","journal-title":"J. Environ. Eng. Geophys."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1002\/ppp.616","article-title":"Advances in geophysical methods for permafrost investigations","volume":"19","author":"Kneisel","year":"2008","journal-title":"Permafr. Periglac. Process."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"3735","DOI":"10.3390\/rs70403735","article-title":"Remotely sensed active layer thickness (ReSALT) at Barrow, Alaska using interferometric synthetic aperture radar","volume":"7","author":"Schaefer","year":"2015","journal-title":"Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1002\/ppp.463","article-title":"Imaging periglacial conditions with ground-penetrating radar","volume":"14","author":"Moorman","year":"2003","journal-title":"Permafr. Periglac. Process."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"41","DOI":"10.5194\/tc-8-41-2014","article-title":"Lidar snow cover studies on glaciers in the Otztal Alps (Austria): comparison with snow depths calculated from GPR measurements","volume":"8","author":"Helfricht","year":"2014","journal-title":"Cryosphere"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1002\/ppp.369","article-title":"Detection of subsurface permafrost features with ground-penetrating radar, Barrow, Alaska","volume":"12","author":"Hinkel","year":"2001","journal-title":"Permafr. Periglac. Process."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.jappgeo.2013.08.013","article-title":"A new fast methodology to estimate the density of frozen materials by means of common offset GPR data","volume":"99","author":"Forte","year":"2013","journal-title":"J. Appl. Geophys."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.coldregions.2009.01.007","article-title":"Evolution of high-frequency ground-penetrating radar direct ground wave propagation during thin frozen soil layer development","volume":"57","author":"Steelman","year":"2009","journal-title":"Cold Reg. Sci. Technol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/j.agrformet.2014.03.005","article-title":"Measuring soil frost depth in forest ecosystems with ground penetrating radar","volume":"192","author":"Butnor","year":"2014","journal-title":"Agric. For. Meteorol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2555","DOI":"10.1109\/TGRS.2004.834800","article-title":"Modeling of ground-penetrating radar for accurate characterization of subsurface electric properties","volume":"42","author":"Lambot","year":"2004","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"W09421","DOI":"10.1029\/2007WR006639","article-title":"Uniqueness and stability analysis of hydrogeophysical inversion for time-lapse ground-penetrating radar estimates of shallow soil hydraulic properties","volume":"44","author":"Jadoon","year":"2008","journal-title":"Water Resour. Res."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1","DOI":"10.2136\/vzj2012.0138","article-title":"Effects of near surface soil moisture profiles during evaporation on far-field ground-penetrating radar data: A numerical study","volume":"12","author":"Moghadas","year":"2013","journal-title":"Vadose Zone J."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"3095","DOI":"10.1109\/TGRS.2014.2368831","article-title":"Estimation of hydraulic properties of a sandy soil using ground-based active and passive microwave remote sensing","volume":"53","author":"Jonard","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1073","DOI":"10.1029\/2001RS002529","article-title":"Coupling effects of two electric dipoles on an interface","volume":"37","author":"Slob","year":"2002","journal-title":"Radio Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"L21405","DOI":"10.1029\/2007GL031459","article-title":"Fast evaluation of zero-offset Green\u2019s function for layered media with application to ground-penetrating radar","volume":"34","author":"Lambot","year":"2007","journal-title":"Geophys. Res. Lett."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"W11403","DOI":"10.1029\/2006WR005097","article-title":"Analysis of air-launched ground-penetrating radar techniques to measure the soil surface water content","volume":"42","author":"Lambot","year":"2006","journal-title":"Water Resour. Res."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Jadoon, K.Z., Lambot, S., Weiherm\u00fcller, L., Moghadas, D., Dimitrov, M., and Vereecken, H. (2013, January 2\u20135). Temporal monitoring of the soil freeze-thaw cycles over snow-cover land by using off-ground GPR. Proceedings of 7th International Workshop on Advanced Ground Penetrating Radar (IWAGPR), Nantes, France.","DOI":"10.1109\/IWAGPR.2013.6601518"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1649","DOI":"10.1109\/TGRS.2010.2089691","article-title":"Analysis of horn antenna transfer functions and phase-center position for modeling off-ground GPR","volume":"49","author":"Jadoon","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"2808","DOI":"10.3390\/rs70302808","article-title":"Estimation and validation of RapidEye-based time-series of leaf area index for winter wheat in the Rur catchment (Germany)","volume":"7","author":"Ali","year":"2015","journal-title":"Remote Sens."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"483","DOI":"10.3997\/1873-0604.2010036","article-title":"Quantifying field-scale surface soil water content from proximal GPR signal inversion in the time domain","volume":"8","author":"Jadoon","year":"2010","journal-title":"Near Surf. Geophys."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1","DOI":"10.2136\/vzj2011.0177","article-title":"Estimation of soil hydraulic parameters in the field by integrated hydrogeophysical inversion of time-lapse ground-penetrating radar data","volume":"11","author":"Jadoon","year":"2012","journal-title":"Vadose Zone J."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"H1","DOI":"10.1190\/geo2011-0054.1","article-title":"Accounting for soil surface roughness in the inversion of ultrawideband off-ground GPR signal for soil moisture retrieval","volume":"77","author":"Jonard","year":"2012","journal-title":"Geophysics"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"2295","DOI":"10.1109\/TGRS.2013.2259243","article-title":"Full-wave modeling of near-field radar data for planar layered media reconstruction","volume":"52","author":"Lambot","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/7\/9\/12041\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:48:50Z","timestamp":1760215730000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/7\/9\/12041"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,9,18]]},"references-count":48,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2015,9]]}},"alternative-id":["rs70912041"],"URL":"https:\/\/doi.org\/10.3390\/rs70912041","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,9,18]]}}}