An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator
The continued loss of sea ice in the Northern Hemisphere due to global warming poses a threat to biota and human activities, evidencing the necessity of efficient sea ice monitoring tools. Aiming at the creation of an improved sea ice extent indicator covering the European regional seas, the new Ice...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2021
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-15-2803-2021 https://doaj.org/article/c037d5ac95c24685b9b7763b9df340aa |
id |
ftdoajarticles:oai:doaj.org/article:c037d5ac95c24685b9b7763b9df340aa |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:c037d5ac95c24685b9b7763b9df340aa 2023-05-15T15:16:53+02:00 An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator J. A. Parera-Portell R. Ubach C. Gignac 2021-06-01T00:00:00Z https://doi.org/10.5194/tc-15-2803-2021 https://doaj.org/article/c037d5ac95c24685b9b7763b9df340aa EN eng Copernicus Publications https://tc.copernicus.org/articles/15/2803/2021/tc-15-2803-2021.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-15-2803-2021 1994-0416 1994-0424 https://doaj.org/article/c037d5ac95c24685b9b7763b9df340aa The Cryosphere, Vol 15, Pp 2803-2818 (2021) Environmental sciences GE1-350 Geology QE1-996.5 article 2021 ftdoajarticles https://doi.org/10.5194/tc-15-2803-2021 2022-12-31T06:41:07Z The continued loss of sea ice in the Northern Hemisphere due to global warming poses a threat to biota and human activities, evidencing the necessity of efficient sea ice monitoring tools. Aiming at the creation of an improved sea ice extent indicator covering the European regional seas, the new IceMap500 algorithm has been developed to classify sea ice and water at a resolution of 500 m at nadir. IceMap500 features a classification strategy built upon previous MODIS sea ice extent algorithms and a new method to reclassify areas affected by resolution-breaking features inherited from the MODIS cloud mask. This approach results in an enlargement of mapped area, a reduction of potential error sources and a better delineation of the sea ice edge, while still systematically achieving accuracies above 90 %, as obtained by manual validation. Swath maps have been aggregated at a monthly scale to obtain sea ice extent with a method that is sensitive to spatio-temporal variations in the sea ice cover and that can be used as an additional error filter. The resulting dataset, covering the months of maximum and minimum sea ice extent (i.e. March and September) over 2 decades (from 2000 to 2019), demonstrates the algorithm's applicability as a monitoring tool and as an indicator, illustrating the sea ice decline at a regional scale. The European sea regions located in the Arctic, NE Atlantic and Barents seas display clear negative trends in both March ( −27.98 ± 6.01 × 10 3 km 2 yr −1 ) and September ( −16.47 ± 5.66 × 10 3 km 2 yr −1 ). Such trends indicate that the sea ice cover is shrinking at a rate of ∼ 9 % and ∼ 13 % per decade, respectively, even though the sea ice extent loss is comparatively ∼ 70 % greater in March. Article in Journal/Newspaper Arctic Global warming Sea ice The Cryosphere Directory of Open Access Journals: DOAJ Articles Arctic The Cryosphere 15 6 2803 2818 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 J. A. Parera-Portell R. Ubach C. Gignac An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
The continued loss of sea ice in the Northern Hemisphere due to global warming poses a threat to biota and human activities, evidencing the necessity of efficient sea ice monitoring tools. Aiming at the creation of an improved sea ice extent indicator covering the European regional seas, the new IceMap500 algorithm has been developed to classify sea ice and water at a resolution of 500 m at nadir. IceMap500 features a classification strategy built upon previous MODIS sea ice extent algorithms and a new method to reclassify areas affected by resolution-breaking features inherited from the MODIS cloud mask. This approach results in an enlargement of mapped area, a reduction of potential error sources and a better delineation of the sea ice edge, while still systematically achieving accuracies above 90 %, as obtained by manual validation. Swath maps have been aggregated at a monthly scale to obtain sea ice extent with a method that is sensitive to spatio-temporal variations in the sea ice cover and that can be used as an additional error filter. The resulting dataset, covering the months of maximum and minimum sea ice extent (i.e. March and September) over 2 decades (from 2000 to 2019), demonstrates the algorithm's applicability as a monitoring tool and as an indicator, illustrating the sea ice decline at a regional scale. The European sea regions located in the Arctic, NE Atlantic and Barents seas display clear negative trends in both March ( −27.98 ± 6.01 × 10 3 km 2 yr −1 ) and September ( −16.47 ± 5.66 × 10 3 km 2 yr −1 ). Such trends indicate that the sea ice cover is shrinking at a rate of ∼ 9 % and ∼ 13 % per decade, respectively, even though the sea ice extent loss is comparatively ∼ 70 % greater in March. |
format |
Article in Journal/Newspaper |
author |
J. A. Parera-Portell R. Ubach C. Gignac |
author_facet |
J. A. Parera-Portell R. Ubach C. Gignac |
author_sort |
J. A. Parera-Portell |
title |
An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
title_short |
An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
title_full |
An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
title_fullStr |
An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
title_full_unstemmed |
An improved sea ice detection algorithm using MODIS: application as a new European sea ice extent indicator |
title_sort |
improved sea ice detection algorithm using modis: application as a new european sea ice extent indicator |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/tc-15-2803-2021 https://doaj.org/article/c037d5ac95c24685b9b7763b9df340aa |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Global warming Sea ice The Cryosphere |
genre_facet |
Arctic Global warming Sea ice The Cryosphere |
op_source |
The Cryosphere, Vol 15, Pp 2803-2818 (2021) |
op_relation |
https://tc.copernicus.org/articles/15/2803/2021/tc-15-2803-2021.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-15-2803-2021 1994-0416 1994-0424 https://doaj.org/article/c037d5ac95c24685b9b7763b9df340aa |
op_doi |
https://doi.org/10.5194/tc-15-2803-2021 |
container_title |
The Cryosphere |
container_volume |
15 |
container_issue |
6 |
container_start_page |
2803 |
op_container_end_page |
2818 |
_version_ |
1766347175726415872 |