{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T09:31:27Z","timestamp":1774690287570,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,14]],"date-time":"2022-11-14T00:00:00Z","timestamp":1668384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003130","name":"Research Foundation - Flanders","doi-asserted-by":"publisher","award":["1113020N"],"award-info":[{"award-number":["1113020N"]}],"id":[{"id":"10.13039\/501100003130","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Full 3D inversion of time-domain Airborne ElectroMagnetic (AEM) data requires specialists\u2019 expertise and a tremendous amount of computational resources, not readily available to everyone. Consequently, quasi-2D\/3D inversion methods are prevailing, using a much faster but approximate (1D) forward model. We propose an appraisal tool that indicates zones in the inversion model that are not in agreement with the multidimensional data and therefore, should not be interpreted quantitatively. The image appraisal relies on multidimensional forward modeling to compute a so-called normalized gradient. Large values in that gradient indicate model parameters that do not fit the true multidimensionality of the observed data well and should not be interpreted quantitatively. An alternative approach is proposed to account for imperfect forward modeling, such that the appraisal tool is computationally inexpensive. The method is demonstrated on an AEM survey in a salinization context, revealing possible problematic zones in the estimated fresh\u2013saltwater interface.<\/jats:p>","DOI":"10.3390\/rs14225757","type":"journal-article","created":{"date-parts":[[2022,11,15]],"date-time":"2022-11-15T02:32:16Z","timestamp":1668479536000},"page":"5757","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Novel Airborne EM Image Appraisal Tool for Imperfect Forward Modeling"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4481-1801","authenticated-orcid":false,"given":"Wouter","family":"Deleersnyder","sequence":"first","affiliation":[{"name":"Laboratory of Applied Geology and Hydrogeology, Department of Geology, Ghent University, Krijgslaan 281-S8, 9000 Ghent, Belgium"},{"name":"Department of Physics, KU Leuven Campus Kortrijk\u2014KULAK, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium"}]},{"given":"David","family":"Dudal","sequence":"additional","affiliation":[{"name":"Department of Physics, KU Leuven Campus Kortrijk\u2014KULAK, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium"},{"name":"Department of Physics and Astronomy, Ghent University, Ghent, Krijgslaan 281-S9, 9000 Gent, Belgium"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9522-1540","authenticated-orcid":false,"given":"Thomas","family":"Hermans","sequence":"additional","affiliation":[{"name":"Laboratory of Applied Geology and Hydrogeology, Department of Geology, Ghent University, Krijgslaan 281-S8, 9000 Ghent, Belgium"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,14]]},"reference":[{"key":"ref_1","first-page":"387","article-title":"Developments in broadband airborne electromagnetics in the past decade","volume":"7","author":"Macnae","year":"2007","journal-title":"Proc. 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