Sea Ice Thematic Data Product [ALT_TDP_SI]

This is the Sea Ice Thematic Data Product (TDP) V1 resulting from the _$$ESA FDR4ALT project$$ https://www.fdr4alt.org/ and containing the sea ice related geophysical parameters, along with associated uncertainties: snow depth, radar and sea-ice freeboard, sea ice thickness and concentration.
The collection covers data for the ERS-1, ERS-2 and Envisat missions, and bases on Level 1 data coming from previous reprocessing (ERS REAPER and the Envisat V3.0) but taking into account the improvements made at Level 0/Level 1 in the frame of FDR4ALT (_$$ALT FDR$$ https://earth.esa.int/eogateway/catalog/fdr-for-altimetry).
The Sea Ice TDP provides data from the northern or southern hemisphere in two files corresponding to the Arctic and Antarctic regions respectively for the winter periods only, i.e., October to June for the Arctic, and May to November for the Antarctic.
For many aspects, the Sea Ice TDP is very innovative:

First time series of sea-ice thickness estimates for ERS
Homogeneous calibration, allowing the first Arctic radar freeboard time series from ERS-1 (1991) to CryoSat-2 (2021)
Uncertainties estimated along-track with a bottom-up approach based on dominant sources
ERS pulse blurring error corrected using literature procedure [Peacock, 2004]
The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used.
Information for expert altimetry users is also available in a dedicated NetCDF group within the products.
Please consult the _$$FDR4ALT Product User Guide$$ https://earth.esa.int/eogateway/documents/d/earth-online/fdr4alt-products-user-guide before using the data.
The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

本数据集为《海冰主题数据产品》（TDP）V1版本，由$$ESA FDR4ALT项目$$（https://www.fdr4alt.org/）生成，包含与海冰相关的地球物理参数及其相关不确定性：雪深、雷达和海冰浮标高度、海冰厚度和浓度。该数据集涵盖ERS-1、ERS-2和Envisat任务的数据，基于先前重处理（ERS REAPER和Envisat V3.0）的Level 1数据，同时考虑了FDR4ALT框架内0/1级改进（$$ALT FDR$$ https://earth.esa.int/eogateway/catalog/fdr-for-altimetry）。《海冰TDP》提供北半球或南半球的数据，分别对应北极和南极地区，仅限于冬季时段，即北极的10月至6月，南极的5月至11月。在许多方面，《海冰TDP》具有显著的创新性：首次为ERS提供海冰厚度估计的时间序列；实现统一的校准，使得从ERS-1（1991年）到CryoSat-2（2021年）的首次北极雷达浮标时间序列成为可能；通过自下而上的方法，基于主导来源沿轨估计不确定性；利用文献方法[Peacock, 2004]纠正ERS脉冲模糊误差。《FDR4ALT》产品以NetCDF格式提供。可使用免费标准工具读取NetCDF数据。产品中还包含专门针对专家海面高度计用户的NetCDF分组信息。请在使用数据前查阅$$FDR4ALT产品用户指南$$（https://earth.esa.int/eogateway/documents/d/earth-online/fdr4alt-products-user-guide）。FDR4ALT数据集代表了ERS/Envisat海面高度计任务的最新参考数据，取代了任何先前任务的数据。强烈建议用户使用这些数据集以获得最佳结果。