Monitoring of thin sea ice within polynyas using MODIS data
Arctic and Antarctic polynya systems are of high research interest since extensive new ice formation takes place in these regions. The monitoring of polynyas and the ice production is crucial with respect to the changing sea-ice regime. The thin-ice thickness (TIT) distribution within polynyas contr...
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Online Access: | https://ubt.opus.hbz-nrw.de/frontdoor/index/index/docId/559 https://nbn-resolving.org/urn:nbn:de:hbz:385-7818 https://doi.org/10.25353/ubtr-xxxx-8f42-8404 https://ubt.opus.hbz-nrw.de/files/559/Adams_Diss_20120710_final.pdf |
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ftunivtrier:oai:ubt.opus.hbz-nrw.de:559 2024-01-14T10:01:34+01:00 Monitoring of thin sea ice within polynyas using MODIS data Beobachtung des dünnen Meereises in Polynjen anhand von MODIS Daten Adams, Susanne 2012-12-18 application/pdf https://ubt.opus.hbz-nrw.de/frontdoor/index/index/docId/559 https://nbn-resolving.org/urn:nbn:de:hbz:385-7818 https://doi.org/10.25353/ubtr-xxxx-8f42-8404 https://ubt.opus.hbz-nrw.de/files/559/Adams_Diss_20120710_final.pdf eng eng https://ubt.opus.hbz-nrw.de/frontdoor/index/index/docId/559 urn:nbn:de:hbz:385-7818 doi:10.25353/ubtr-xxxx-8f42-8404 https://ubt.opus.hbz-nrw.de/files/559/Adams_Diss_20120710_final.pdf info:eu-repo/semantics/openAccess Fernerkundung 4016796-3 Meereis 4131349-5 MODIS 4191470-3 Polynja 4123965-9 Laptewsee 4377883-5 Geowissenschaften ddc:550 doctoralthesis doc-type:doctoralThesis 2012 ftunivtrier https://doi.org/10.25353/ubtr-xxxx-8f42-8404 2023-12-17T23:34:58Z Arctic and Antarctic polynya systems are of high research interest since extensive new ice formation takes place in these regions. The monitoring of polynyas and the ice production is crucial with respect to the changing sea-ice regime. The thin-ice thickness (TIT) distribution within polynyas controls the amount of heat that is released to the atmosphere and has therefore an impact on the ice-production rates. This thesis presents an improved method to retrieve thermal-infrared thin-ice thickness distributions within polynyas. TIT with a spatial resolution of 1 km × 1 km is calculated using the MODIS ice-surface temperature and atmospheric model variables within the Laptev Sea polynya for the winter periods 2007/08 and 2008/09. The improvement of the algorithm is focused on the surface-energy flux parameterizations. Furthermore, a thorough sensitivity analysis is applied to quantify the uncertainty in the thin-ice thickness results. An absolute mean uncertainty of -±4.7 cm for ice below 20 cm of thickness is calculated. Furthermore, advantages and drawbacks using different atmospheric data sets are investigated. Daily MODIS TIT composites are computed to fill the data gaps arising from clouds and shortwave radiation. The resulting maps cover on average 70 % of the Laptev Sea polynya. An intercomparison of MODIS and AMSR-E polynya data indicates that the spatial resolution issue is essential for accurately deriving polynya characteristics. Monthly fast-ice masks are generated using the daily TIT composites. These fast-ice masks are implemented into the coupled sea-ice/ocean model FESOM. An evaluation of FESOM sea-ice concentrations is performed with the result that a prescribed high-resolution fast-ice mask is necessary regarding the accurate polynya location. However, for a more realistic simulation of other small-scale sea-ice features further model improvements are required. The retrieval of daily high-resolution MODIS TIT composites is an important step towards a more precise monitoring of thin sea ice and ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Arctic laptev Laptev Sea Sea ice Publication Server of Tier University (OPUS) Antarctic Arctic Laptev Sea |
institution |
Open Polar |
collection |
Publication Server of Tier University (OPUS) |
op_collection_id |
ftunivtrier |
language |
English |
topic |
Fernerkundung 4016796-3 Meereis 4131349-5 MODIS 4191470-3 Polynja 4123965-9 Laptewsee 4377883-5 Geowissenschaften ddc:550 |
spellingShingle |
Fernerkundung 4016796-3 Meereis 4131349-5 MODIS 4191470-3 Polynja 4123965-9 Laptewsee 4377883-5 Geowissenschaften ddc:550 Adams, Susanne Monitoring of thin sea ice within polynyas using MODIS data |
topic_facet |
Fernerkundung 4016796-3 Meereis 4131349-5 MODIS 4191470-3 Polynja 4123965-9 Laptewsee 4377883-5 Geowissenschaften ddc:550 |
description |
Arctic and Antarctic polynya systems are of high research interest since extensive new ice formation takes place in these regions. The monitoring of polynyas and the ice production is crucial with respect to the changing sea-ice regime. The thin-ice thickness (TIT) distribution within polynyas controls the amount of heat that is released to the atmosphere and has therefore an impact on the ice-production rates. This thesis presents an improved method to retrieve thermal-infrared thin-ice thickness distributions within polynyas. TIT with a spatial resolution of 1 km × 1 km is calculated using the MODIS ice-surface temperature and atmospheric model variables within the Laptev Sea polynya for the winter periods 2007/08 and 2008/09. The improvement of the algorithm is focused on the surface-energy flux parameterizations. Furthermore, a thorough sensitivity analysis is applied to quantify the uncertainty in the thin-ice thickness results. An absolute mean uncertainty of -±4.7 cm for ice below 20 cm of thickness is calculated. Furthermore, advantages and drawbacks using different atmospheric data sets are investigated. Daily MODIS TIT composites are computed to fill the data gaps arising from clouds and shortwave radiation. The resulting maps cover on average 70 % of the Laptev Sea polynya. An intercomparison of MODIS and AMSR-E polynya data indicates that the spatial resolution issue is essential for accurately deriving polynya characteristics. Monthly fast-ice masks are generated using the daily TIT composites. These fast-ice masks are implemented into the coupled sea-ice/ocean model FESOM. An evaluation of FESOM sea-ice concentrations is performed with the result that a prescribed high-resolution fast-ice mask is necessary regarding the accurate polynya location. However, for a more realistic simulation of other small-scale sea-ice features further model improvements are required. The retrieval of daily high-resolution MODIS TIT composites is an important step towards a more precise monitoring of thin sea ice and ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Adams, Susanne |
author_facet |
Adams, Susanne |
author_sort |
Adams, Susanne |
title |
Monitoring of thin sea ice within polynyas using MODIS data |
title_short |
Monitoring of thin sea ice within polynyas using MODIS data |
title_full |
Monitoring of thin sea ice within polynyas using MODIS data |
title_fullStr |
Monitoring of thin sea ice within polynyas using MODIS data |
title_full_unstemmed |
Monitoring of thin sea ice within polynyas using MODIS data |
title_sort |
monitoring of thin sea ice within polynyas using modis data |
publishDate |
2012 |
url |
https://ubt.opus.hbz-nrw.de/frontdoor/index/index/docId/559 https://nbn-resolving.org/urn:nbn:de:hbz:385-7818 https://doi.org/10.25353/ubtr-xxxx-8f42-8404 https://ubt.opus.hbz-nrw.de/files/559/Adams_Diss_20120710_final.pdf |
geographic |
Antarctic Arctic Laptev Sea |
geographic_facet |
Antarctic Arctic Laptev Sea |
genre |
Antarc* Antarctic Arctic laptev Laptev Sea Sea ice |
genre_facet |
Antarc* Antarctic Arctic laptev Laptev Sea Sea ice |
op_relation |
https://ubt.opus.hbz-nrw.de/frontdoor/index/index/docId/559 urn:nbn:de:hbz:385-7818 doi:10.25353/ubtr-xxxx-8f42-8404 https://ubt.opus.hbz-nrw.de/files/559/Adams_Diss_20120710_final.pdf |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.25353/ubtr-xxxx-8f42-8404 |
_version_ |
1788067326588878848 |