also find out what's new for land ice, summer sea ice, sea ice (NRT), polar oceans, polar oceans (NRT), coastal oceans, inland waters,
See the product downloads page for access details.
The following evolutions have been applied in Baseline-D (released May 2025) as compared to Baseline-C (released April 2024). Further details are provided in the Cryo-TEMPO Product Handbook and ATBD documents.
Added gridded Level-3 data for the northern and southern hemisphere.
Update tided model to FES2022.
Added sub-waveform retracking of sea ice waveforms using SAMOSA+. This change has been implemented to improve the accuracy of SAMOSA+ for waveforms from heterogenous sea ice conditions.
Compute range uncertainty directly from the SAMOSA+ fitting process. Before, the range uncertainty was a fixed value (expert guess).
Use SAMOSA+ retracker properties to filter radar freeboard data when the main waveform peak is likely from an off-nadir target.
New Variable / Filter: Added marginal ice zone filter flag. The filter flags freeboard values that are likely biased by ocean swell in the marginal ice zone.
Use of the latest evolution of ESA L1b data set as input (for all products). Only ESA CS2 Baseline-E L1b data is used as input to the CryoTEMPO processing (in CryoTEMPO Baseline-B it was necessary to use a sub-optimal mix of available data from L1b Baseline-D and Baseline-E).
Sea ice products are now also produced for the southern hemisphere. In previous baselines only the northern hemisphere was covered. Southern hemisphere data is produced for all month of the year.
The SAMOSA+ waveform model replaces the Threshold First Maximum Retracker Algorithm (TFMRA) as range estimation algorithm for sea ice and lead waveforms. The SAMOSA+ retracker is better suited for waveforms with variable surface roughness. This comes at the cost of significantly higher computational load. Near real-time data is therefore still delivered with the TFMRA retracker.
New near real time (NRT) sea ice data produced in Baseline-C for winter sea ice products, delivered within 18h in addition to the delivery of regular data within 31 days. See separate theme section for NRT data
A new region_code parameter has been included. This provided the Arctic region indentifier (0..18) for every measurement. The regions are adapted from 'A new regional mask for Arctic sea ice trends and climatologies (J. Scott Stewart and Walter N. Meier, NSIDC)'
Tide correction now uses the ARCTIDE (v1.1) tidal model where available. FES2014b is used where ARCTIDE is not available (outside it's Arctic grid area).
Further information on ARCTIDE is provided by the reference: M. Cancet, O. B. Andersen, F. Lyard, D. Cotton, and J. Benveniste, ‘Arctide2017, a high-resolution regional tidal model in the Arctic Ocean’, Advances in Space Research, vol. 62, no. 6, pp. 1324–1343, 2018, doi: 10.1016/j.asr.2018.01.007).
DAC (Dynamic Atmosphere Correction) now used instead of IB (Inverted Barometer). The DAC includes the IB correction as well as a high frequency MOG2D barometric model forced by wind and pressure.
Mean Sea Surface (MSS) has been updated from the DTU15 to DTU21. The reference for DTU21 is Andersen, Ole Baltazar (2022): DTU21 Mean Sea Surface. Technical University of Denmark. Dataset. https://doi.org/10.11583/DTU.19383221.v1 )