High-resolution sea ice drift and deformation from sequential SAR images in the Transpolar Drift during MOSAiC 2019/2020 ...

• Main Authors: von Albedyll, Luisa, Hutter, Nils
• Format: Dataset
• Language: English
• Published: PANGAEA 2023
• Subjects: DATE/TIME; netCDF file; netCDF file File Size; Satellite imagery; Multidisciplinary drifting Observatory for the Study of Arctic Climate MOSAiC; Arctic; The ''Y''; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.958449; https://doi.pangaea.de/10.1594/PANGAEA.958449

Sea ice deformation is a crucial process in the polar climate system and, thus, it is an important cross-cutting theme for all disciplines of the interdisciplinary research expedition MOSAiC. Because sea ice deformation is highly localized and intermittent, drift and deformation with a high spatial and temporal resolution and a large spatial coverage are required for a comprehensive description of the sea ice dynamics. We provide a regularly gridded, high-resolution drift and deformation dataset that can be used for several potential applications. Drift fields were obtained from Sentinel-1, HH polarization SAR images acquired in enhanced wide mode. These had a pixel resolution of 50 m in Polar Stereographic North projection (latitude of true scale: 70 N, center longitude: 45 W). We used an ice-tracking algorithm introduced by Thomas et al. (2008, 2011) and modified by Hollands and Dierking (2011) to derive drift from sequential pairs. Typically, the time between two scenes was one day, with a few exceptions ... : Data is provided in NetCDF format and in the Polar Stereographic North projection (latitude of true scale: 70 N, center longitude: 45 W, EPSG:3413). All files are projected to the same grid with a spatial resolution of 700 m. There is one file available for each time step (indicated in the file name). Each file contains drift and deformation information.For geographic reference, the files contain:• latitude• longitude• projected x-coordinate (of the polar stereographic projection)• projected y-coordinate (of the polar stereographic projection)For the sea ice drift, the following variables are available:• sea_ice_x_velocity (u, given along the x-direction)• sea_ice_y_velocity (v, given along the y-direction)• sea_ice_speed (absolute speed)• direction_of_sea_ice_velocity (direction)• sea_ice_drift_reliability_flag (indicates the quality of the drift estimates)For the deformation, there are the following variables:• the spatial derivatives (dudx, dudy, dvdx, dvdy)• divergence,• shear,• total deformation,• ...