Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system
Sea ice is an important climate variable and is also an obstacle for marine operations in polar regions. We have developed a small and lightweight, digitally operated frequency-domain electromagnetic-induction (EM) system, a so-called EM bird, dedicated for measurements of sea ice thickness. It is 3...
Published in: | Journal of Applied Geophysics |
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Language: | English |
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2009
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Online Access: | https://oceanrep.geomar.de/id/eprint/28493/ https://oceanrep.geomar.de/id/eprint/28493/1/2009_Haas-etal-JApplGeo-67.pdf https://doi.org/10.1016/j.jappgeo.2008.05.005 |
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ftoceanrep:oai:oceanrep.geomar.de:28493 2023-05-15T18:17:32+02:00 Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system Haas, Christian Lobach, John Hendricks, Stefan Rabenstein, Lasse Pfaffling, Andreas 2009 text https://oceanrep.geomar.de/id/eprint/28493/ https://oceanrep.geomar.de/id/eprint/28493/1/2009_Haas-etal-JApplGeo-67.pdf https://doi.org/10.1016/j.jappgeo.2008.05.005 en eng Elsevier https://oceanrep.geomar.de/id/eprint/28493/1/2009_Haas-etal-JApplGeo-67.pdf Haas, C., Lobach, J., Hendricks, S., Rabenstein, L. and Pfaffling, A. (2009) Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system. Open Access Journal of Applied Geophysics, 67 (3). pp. 234-241. DOI 10.1016/j.jappgeo.2008.05.005 <https://doi.org/10.1016/j.jappgeo.2008.05.005>. doi:10.1016/j.jappgeo.2008.05.005 cc_by_nc_3.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2009 ftoceanrep https://doi.org/10.1016/j.jappgeo.2008.05.005 2023-04-07T15:18:57Z Sea ice is an important climate variable and is also an obstacle for marine operations in polar regions. We have developed a small and lightweight, digitally operated frequency-domain electromagnetic-induction (EM) system, a so-called EM bird, dedicated for measurements of sea ice thickness. It is 3.5 m long and weighs only 105 kg, and can therefore easily be shipped to remote places and operated from icebreakers and small helicopters. Here, we describe the technical design of the bird operating at two frequencies of f1 = 3.68 kHz and f2 = 112 kHz, and study its technical performance. On average, noise amounts to ± 8.5 ppm and ± 17.5 ppm for f1 and f2, respectively. Electrical drift amounts to 200 ppm/h and 2000 ppm/h for f1 and f2, during the first 0.5 h of operation. It is reduced by 75% after 2 h. Calibration of the Inphase and Quadrature ppm signals varies by 2 to 3%. A sensitivity study shows that all these signal variations do affect the accuracy of the ice thickness retrieval, but that it remains better than ± 0.1 m over level ice in most cases. This accuracy is also confirmed by means of comparisons of the helicopter EM data with other thickness measurements. The paper also presents the ice thickness retrieval from single-component Inphase data of f1. Article in Journal/Newspaper Sea ice OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Journal of Applied Geophysics 67 3 234 241 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Sea ice is an important climate variable and is also an obstacle for marine operations in polar regions. We have developed a small and lightweight, digitally operated frequency-domain electromagnetic-induction (EM) system, a so-called EM bird, dedicated for measurements of sea ice thickness. It is 3.5 m long and weighs only 105 kg, and can therefore easily be shipped to remote places and operated from icebreakers and small helicopters. Here, we describe the technical design of the bird operating at two frequencies of f1 = 3.68 kHz and f2 = 112 kHz, and study its technical performance. On average, noise amounts to ± 8.5 ppm and ± 17.5 ppm for f1 and f2, respectively. Electrical drift amounts to 200 ppm/h and 2000 ppm/h for f1 and f2, during the first 0.5 h of operation. It is reduced by 75% after 2 h. Calibration of the Inphase and Quadrature ppm signals varies by 2 to 3%. A sensitivity study shows that all these signal variations do affect the accuracy of the ice thickness retrieval, but that it remains better than ± 0.1 m over level ice in most cases. This accuracy is also confirmed by means of comparisons of the helicopter EM data with other thickness measurements. The paper also presents the ice thickness retrieval from single-component Inphase data of f1. |
format |
Article in Journal/Newspaper |
author |
Haas, Christian Lobach, John Hendricks, Stefan Rabenstein, Lasse Pfaffling, Andreas |
spellingShingle |
Haas, Christian Lobach, John Hendricks, Stefan Rabenstein, Lasse Pfaffling, Andreas Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
author_facet |
Haas, Christian Lobach, John Hendricks, Stefan Rabenstein, Lasse Pfaffling, Andreas |
author_sort |
Haas, Christian |
title |
Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
title_short |
Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
title_full |
Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
title_fullStr |
Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
title_full_unstemmed |
Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system |
title_sort |
helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital em system |
publisher |
Elsevier |
publishDate |
2009 |
url |
https://oceanrep.geomar.de/id/eprint/28493/ https://oceanrep.geomar.de/id/eprint/28493/1/2009_Haas-etal-JApplGeo-67.pdf https://doi.org/10.1016/j.jappgeo.2008.05.005 |
genre |
Sea ice |
genre_facet |
Sea ice |
op_relation |
https://oceanrep.geomar.de/id/eprint/28493/1/2009_Haas-etal-JApplGeo-67.pdf Haas, C., Lobach, J., Hendricks, S., Rabenstein, L. and Pfaffling, A. (2009) Helicopter-borne measurements of sea ice thickness, using a small and lightweight, digital EM system. Open Access Journal of Applied Geophysics, 67 (3). pp. 234-241. DOI 10.1016/j.jappgeo.2008.05.005 <https://doi.org/10.1016/j.jappgeo.2008.05.005>. doi:10.1016/j.jappgeo.2008.05.005 |
op_rights |
cc_by_nc_3.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.jappgeo.2008.05.005 |
container_title |
Journal of Applied Geophysics |
container_volume |
67 |
container_issue |
3 |
container_start_page |
234 |
op_container_end_page |
241 |
_version_ |
1766191824223862784 |