Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition
Sea ice is a crucial parameter in the Earth climate system. Its high albedo compared to water influences the oceans' radiation budget. The state of sea ice is highly variable due to seasonal change and global warming. GNSS reflectometry can contribute to global monitoring sea ice. Properties li...
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ftdlr:oai:elib.dlr.de:143534 2024-05-19T07:27:45+00:00 Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition Semmling, Maximilian Wickert, Jens Kreß, Frederik Hoque, Mohammed Mainul Divine, Dmitry V. Gerland, Sebastian 2021 application/pdf https://elib.dlr.de/143534/ https://elib.dlr.de/143534/1/210616_iag_e-post_semmling_et_al.pdf en eng https://elib.dlr.de/143534/1/210616_iag_e-post_semmling_et_al.pdf Semmling, Maximilian und Wickert, Jens und Kreß, Frederik und Hoque, Mohammed Mainul und Divine, Dmitry V. und Gerland, Sebastian (2021) Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition. IAG 2021, 2021-06-28 - 2021-07-02, Beijing, China. Weltraumwetterbeobachtung Konferenzbeitrag NonPeerReviewed 2021 ftdlr 2024-04-25T00:56:38Z Sea ice is a crucial parameter in the Earth climate system. Its high albedo compared to water influences the oceans' radiation budget. The state of sea ice is highly variable due to seasonal change and global warming. GNSS reflectometry can contribute to global monitoring sea ice. Properties like ice salinity, temperature and thickness affect the signal reflection. The MOSAiC expedition (Multidisciplinary drifting Observatory for the Study of Arctic Climate) gave the opportunity to conduct reflectometry measurements under different sea-ice conditions in the Arctic. A dedicated setup was mounted, in close cooperation with the Alfred-Wegener-Institute (AWI), on the German research icebreaker Polarstern that drifted during nine months with the Arctic sea ice. Here, results from the expedition's first leg in autumn 2019 are presented when the ship started drifting at about 85°N to 87°N in the Siberian Sector of the Arctic. Profiles of sea-ice reflectivity are derived with daily resolution considering reflection data recorded at left-handed (LH) and righthanded (RH) circular polarization. Respective predictions of reflectivity are provided assuming reflection models of bulk sea ice or a sea-ice slab. The later allows to include the effect of signal penetration down to the underlying water. Results of comparison between LH profiles and bulk model confirm that the reflectivity decreases (about 10 dB) when the ship goes into compact sea ice. In the central Arctic period anomaly signatures in observed reflectivity occur. The comparison of signatures and applied models (bulk and slab) indicate the role of coherent signal penetration into the ice. Salinity and temperature of sea ice have influence on these signatures. We conclude that estimation of ice type/salinity and temperature can profit from grazing angle GNSS reflectometry. Future studies will proceed to investigate these signatures in coherent observations. Conference Object albedo Arctic Global warming Icebreaker Sea ice German Aerospace Center: elib - DLR electronic library |
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German Aerospace Center: elib - DLR electronic library |
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English |
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Weltraumwetterbeobachtung |
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Weltraumwetterbeobachtung Semmling, Maximilian Wickert, Jens Kreß, Frederik Hoque, Mohammed Mainul Divine, Dmitry V. Gerland, Sebastian Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
topic_facet |
Weltraumwetterbeobachtung |
description |
Sea ice is a crucial parameter in the Earth climate system. Its high albedo compared to water influences the oceans' radiation budget. The state of sea ice is highly variable due to seasonal change and global warming. GNSS reflectometry can contribute to global monitoring sea ice. Properties like ice salinity, temperature and thickness affect the signal reflection. The MOSAiC expedition (Multidisciplinary drifting Observatory for the Study of Arctic Climate) gave the opportunity to conduct reflectometry measurements under different sea-ice conditions in the Arctic. A dedicated setup was mounted, in close cooperation with the Alfred-Wegener-Institute (AWI), on the German research icebreaker Polarstern that drifted during nine months with the Arctic sea ice. Here, results from the expedition's first leg in autumn 2019 are presented when the ship started drifting at about 85°N to 87°N in the Siberian Sector of the Arctic. Profiles of sea-ice reflectivity are derived with daily resolution considering reflection data recorded at left-handed (LH) and righthanded (RH) circular polarization. Respective predictions of reflectivity are provided assuming reflection models of bulk sea ice or a sea-ice slab. The later allows to include the effect of signal penetration down to the underlying water. Results of comparison between LH profiles and bulk model confirm that the reflectivity decreases (about 10 dB) when the ship goes into compact sea ice. In the central Arctic period anomaly signatures in observed reflectivity occur. The comparison of signatures and applied models (bulk and slab) indicate the role of coherent signal penetration into the ice. Salinity and temperature of sea ice have influence on these signatures. We conclude that estimation of ice type/salinity and temperature can profit from grazing angle GNSS reflectometry. Future studies will proceed to investigate these signatures in coherent observations. |
format |
Conference Object |
author |
Semmling, Maximilian Wickert, Jens Kreß, Frederik Hoque, Mohammed Mainul Divine, Dmitry V. Gerland, Sebastian |
author_facet |
Semmling, Maximilian Wickert, Jens Kreß, Frederik Hoque, Mohammed Mainul Divine, Dmitry V. Gerland, Sebastian |
author_sort |
Semmling, Maximilian |
title |
Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
title_short |
Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
title_full |
Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
title_fullStr |
Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
title_full_unstemmed |
Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition |
title_sort |
sea-ice signatures in coherently reflected gnss signals: findings of the mosaic expedition |
publishDate |
2021 |
url |
https://elib.dlr.de/143534/ https://elib.dlr.de/143534/1/210616_iag_e-post_semmling_et_al.pdf |
genre |
albedo Arctic Global warming Icebreaker Sea ice |
genre_facet |
albedo Arctic Global warming Icebreaker Sea ice |
op_relation |
https://elib.dlr.de/143534/1/210616_iag_e-post_semmling_et_al.pdf Semmling, Maximilian und Wickert, Jens und Kreß, Frederik und Hoque, Mohammed Mainul und Divine, Dmitry V. und Gerland, Sebastian (2021) Sea-ice signatures in coherently reflected GNSS signals: Findings of the MOSAiC expedition. IAG 2021, 2021-06-28 - 2021-07-02, Beijing, China. |
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1799468923378204672 |