Abstract:
This dataset contains the floe size distribution (FSD) data derived from multi-satellite imagery data acquired across the Arctic Ocean. Satellite imagery data includes high-resolution visible images from the USGS Global Fiducials Library (MEDEA), TerraSAR-X/TanDEM-X and Worldview-3 (WV3). The derived data contain floe size (calliper diameter), shape factor, minor/major axis, perimeter and area of the floes. This data set has been used to investigate the characteristics of the FSD during major seasonal evaluation stages of Arctic sea ice floes. The retrieval of the FSD data was done by the University of Huddersfield team.
This work was funded by NERC MOSAiC program NE/S002545/1.
Keywords:
Arctic, MOSAiC, floe size distribution, lateral melt, melt fragmentation, sea ice, wave fracture
Hwang, B., Wang, Y., & MOSAiC Remote Sensing Team. (2022). Multi-satellite floe size distribution of Arctic sea ice 2000-2020 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/7dc6e19d-79fa-41f1-99a7-da408592382f
| Access Constraints: | No restrictions apply. |
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| Use Constraints: | Data supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/. |
| Creation Date: | 2022-07-07 |
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| Dataset Progress: | Complete |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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| Personnel: | |
| Name | UK Polar Data Centre |
| Role(s) | Metadata Author |
| Organisation | British Antarctic Survey |
| Name | Byongjun Hwang |
| Role(s) | Investigator, Technical Contact |
| Organisation | University of Huddersfield |
| Name | Yanan Wang |
| Role(s) | Investigator |
| Organisation | University of Huddersfield |
| Name | MOSAiC remote sensing team |
| Role(s) | Investigator |
| Organisation | MOSAiC expedition |
| Parent Dataset: | N/A |
| Reference: | Hwang B, Wang Y. 2022 Multi-scale satellite observations of Arctic sea ice: new insight into the life cycle of the floe size distribution. Phil. Trans. R. Soc. A 380: 20210259. https://doi.org/10.1098/rsta.2021.0259 Hwang, B., J. Ren, S. McCormack, C. Berry, I. Ben Ayed, H. Graber, and E. Aptoula (2017) A practical algorithm for the retrieval of sea ice floe size distribution from high-resolution Synthetic Aperture Radar imagery, Elem Sci Anth, 2017;5:38. https://doi.org/10.1525/elementa.154 |
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| Quality: | The data quality was checked by manual inspection for each imagery data. It should be noted that some of the small floes can be erroneous due to noises or internal variations within the images. However, no minimum threshold for the smallest detectable floes was set for this dataset (i.e., the smallest floe equals one image pixel). This is to provide flexibility for the users to select the minimum threshold for the smallest detectable floes. For instance, in our observational study, the minimum threshold was set to be 5 m for MEDEA/WV images (i.e., the floes small than 5 m in diameter were discarded from the analysis) and 15 m for TerraSAR-X images (i.e., the floes small than 15 m in diameter were discarded from the analysis). | |
| Lineage: | The FSD data were derived from multi-satellite imagery data, including MEDEA, TerraSAR-X/TanDEM-X and WorldView-3. For MEDEA images, the selected images were cropped to remove the areas with clouds and missing data. The cropped images were then used to derive the FSD. For TerraSAR-X/TanDEM-X images, the raw data (Level 1B products) were acquired from DLR (under TSX SSS project hwang_OCE3757). The images were applied to ellipsoid correction (range doppler) and speckle filter (median) and converted to GeoTIFF files. Those GeoTIFF files were used to derive the FSD. For WorldView-3, panchromatic images were used to derive the FSD. The floe size distribution was derived from those images using the algorithm described in Hwang et al. (2017). | |
| Temporal Coverage: | |
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| Start Date | 2000-01-01 |
| End Date | 2020-12-31 |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | 61.98 |
| Northernmost | 85 |
| Longitude | |
| Westernmost | -170 |
| Easternmost | 8.93 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Data Resolution: | |
| Latitude Resolution | N/A |
| Longitude Resolution | N/A |
| Horizontal Resolution Range | 1 meter - < 30 meters |
| Vertical Resolution | N/A |
| Vertical Resolution Range | N/A |
| Temporal Resolution | N/A |
| Temporal Resolution Range | N/A |
| Location: | |
| Location | Arctic |
| Detailed Location | Arctic Ocean |
| Data Collection: | Characteristics of satellite imagery data used to derive the FSD data are described below. MEDEA: 1-m resolution visible (panchromatic) satellite imagery from the USGS Global Fiducials Library (GFL) (https://gfl.usgs.gov), declassified by the MEDEA group. TerraSAR-X or TanDEM-X: X-band satellites operated by the German Aerospace Centre (DLR, www.dlr.de). For the FSD retrieval, three image mode data - Spotlight (SL), StripMap (SM) and ScanSAR (SC) were used (for the details of the image modes, see https://earth.esa.int/eogateway/catalog/terrasar-x-esa-archive). WorldView-3: A commercial satellite by Digital Globe (https://www.digitalglobe.com). The FSD data was derived from a panchromatic image of WorldView-3 (WV3). |
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| Distribution: | |
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| Distribution Media | Online Internet (HTTP) |
| Distribution Size | 1.5 GB |
| Distribution Format | N/A |
| Fees | N/A |
| Data Storage: | The dataset is organised in three folders, named Fracturing, Transition and Melt_Wave. These folders represent three key stages of the floe size evolution. In each folder, the data are contained in three folders of sat_image, floe_map and fsd. The folder sat_image contains the pre-processed satellite imagery data in GeoTIFF format (due to the license issue, the original satellite imagery data for TerraSAR-X and Worldview images are not provided in the data set, only raw MEDEA images are provided). The folder floe_map contains the results in black-and-white images (black = water, white = ice) which were generated from the image segmentation, floe separation and manual inspection. The folder fsd contains the text data files generated from the floe map images using blob analysis (identifying individual ice floes from the images). The FSD data files are in CSV (comma-separated values) with the data structure as below. Diameter Metres Mean caliper diameter of the floes ShapeFactor Unitless Ratio of the major axis to the minor axis of the floes (major axis / minor axis) MajorAxis Metres Length of the major axis of the floes MinorAxis Metres Length of the minor axis of the floes Perimeter Metres Perimeter of the floes Area Square metres Area of the floes IcePixelNumber Number Number of the pixels for ice floes |