SIRAL Blog
News and updates to CryoSat-2 sea ice products:
The production of sea ice thickness from CryoSat-2 near real-time data has been resumed for the winter season 2023/24. Documentation of the new version 2.6 will be made available shortly on this page.
CryoSat-2-AWI-v2p6-nrt-20231001_20231003.pngFigure: CryoSat-2 NRT data from the first 3 days of October 2023
Operational production of CrypSat-2 near real time data has been completed for the 2022/23 Arctic winter season. Production will resume in October 2023.
sea_ice_thickness_awi-cryosat2-nrt-nh_202304.pngFinal Arctic sea ice thickness grid (April 2023) from CryoSat-2 nea real-time data
Sea Ice Concentration data from OSI-SAF is (OSI-401-b) is currently not available due to missing DMSP SSMIS Level-1 input data:
https://osi-saf.eumetsat.int/community/list-of-service-messages https://osi-saf.eumetsat.int/community/list-of-service-messages
Daily sea ice concentration data from OSI-401-b is critical input to the CryoSat-2 sea ice product and data from the following dates is missing:
CryoSat-2 l2p
The most recent version of the AWI CryoSat-2 sea ice product has been published on the AWI ftp:
ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p5/nh/ ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p5/nh/
The data release includes a full mission reprocessing from November 2010 and April 2022 and operational processing (including near real-time) from October 2022 onwards.
Reprocessed (33 days delay)
Near-real time (2 days delay)
Daily Trajectory
l2p_trajectory ftp://ftp.awi.…
Production of the near real-time AWI CryoSat-2 sea ice thickness product will start shortly.
Preliminary list of updates compared in v2.5:
New surface type classification (sea ice / lead / open ocean discrimination). The new surface type classification increases the number of waveforms for sea ice freeboard/thickness evaluation.
New flag indicating surface wave influence in the marginal ice zone.…
The release of the baseline-E of CryoSat-2 L1b data (See ESA announcement https://earth.esa.int/eogateway/news/new-ice-baseline-e-and-near-real-time-processors) has provided a fix to missing orbits in the near real-time NRT data (See CryoSat-2 NRT issues remain for a description). The orbit coverage of the CryoSat-2 v2.4 NRT data from October 2021 and later has again the same coverage as the following reprocessed data.
sea_ice_thickness_in_awi-siral-l3c-sithick-cryosat2-nrt-nh_25km.png
Gridded sea-ice thickness from near-real time CryoSat-2 data in October ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p3/nh/l3c_grid/monthly/LATEST/awi-siral-l3c-sithick-cryosat2-nrt-nh_25km_ease2-202010-fv2p3.nc displays a few orbits with large thickness values in the Russian Arctic (see figure below). These are the result of an anomaly in the processing chain/input data and are under investigation.…
The production of operational sea-ice thickness information from near real-time CryoSat-2 data has resumed:
Near-real time (2 days delay)
Daily Trajectory
l2p_trajectory/Latest ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p3/nh/l2p_trajectory/Latest (updated daily)
Weekly Gridded
l3c_grid/weekly/Latest ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p3/nh/l3c_grid/weekly/Latest (updated on Tuesday)
Monthly Gridded
l3c_grid/monthly/Latest ftp://ftp.awi.…
The start of the AWI CryoSat-2 v2.3 near real-time processing is delayed due to ongoing work on a software issue.
Algorithm Updates
The AWI CryoSat-2 sea-ice product is updated annually and the new version is reprocessed every year in fall and operationally generated from October on. The product version from October 2020 on is v2.3 and it contains the following changes compared to v2.2:
Auxiliary Data
Switched C3S sea-ice concentration (interim) climate data record from v1.2 to v2.…
The Copernicus Climate Change Services (C3S) interim climate data (ICDR) record for sea-ice concentration has been discontinued in anticipation of a version update from January 1st, 2020 onwards. This affects the production the CryoSat-2 sea-ice thickness data product with the reprocessed timeliness (+31 days).…
An issue has been identified with CryoSat-2 near-realtime (NRT) data for algorithm baseline-D: The NRT Level-1 data to the CryoSat-2 sea ice product is missing several orbits, mostly in the Russian Arctic as can be seen in the figure below. The offline reprocessed data, which trails the NRT data by one month is not affected by this issue. ESA is aware of the problem and in the process of developing a fix that will be implemented at a later stage.…
The reprocessed data record for the AWI CryoSat-2 sea ice product (version 2.2) is now available on the AWI ftp ftp://ftp.awi.de/sea_ice/product/cryosat2/v2p2/ (Nov 2010 - April 2019). The previous version is deprecated and has been remove. Updates of the reprocessed data stream will start with a delay of 33 days in early November and with 2 day delay for the near-real time data stream in early October.…
The generation of sea-ice thickness from CryoSat-2 will resume in October 2019 with an update of the retrieval algorithm and product content. The changes are listed below:
Altimeter Input Data
CryoSat-2 baseline-D data as primary altimeter data since April 28, 2019. NOTE: In v2.2 the reprocessed grid products consist of a mix between baseline-C and baseline-D
Auxiliary Data
Use C3S (interim) climate data records of sea ice concentration as auxiliary data for the reprocessed data stream.…
CryoSat-2 has now finished its 9th winter from October to April of Arctic sea ice thickness observations. No sea-ice thickness production is now paused for the month of May through September since the snow is warming and will soon start to melt. The impact of snow melt on the sea-ice thickness retrieval is poorly understood and the production will resume in October 2019 with the next version of CryoSat-2 data.
In resume,…
The latest results from CryoSat show that the latest extrema in winter sea ice maximum extent are not necessarily accompanied by a lower mean sea ice thickness of the remaining ice. One factor certainly is that sea ice thickness is a product of thermodynamic ice growth and the acummulated dynamic forces throughout the winter. As a first step in the investigation to what extent dynamic forces have played a role in the last winter,…