Land-ice is declining globally, raising sea levels worldwide and impacting glacial risks and access to fresh-water in high-mountain glaciers regions. Land-ice monitoring via Earth Observation methods in general, and altimetry in particular, are essential for tracking the current status of ice volume change and its evolution as climate continues to evolve and mitigating actions are being pursued.
In this context, ESA launched the CryoSat ThEMatic PrOducts (Cryo-TEMPO) activity that supports a wide variety of end-users working in the areas of sea ice, polar oceans, land ice, coastal areas and hydrology. CryoTEMPO-EOLIS (Elevation Over Land Ice from Swath), went live in 2020 for the Greenland and Antarctic Ice Sheets.
Developed by Earthwave in collaboration with the University of Edinburgh and isardSAT, the EOLIS products exploit CryoSat’s SARIn mode and the novel Swath processing technique to deliver increased spatial and temporal coverage of time-dependent elevation over land ice, a critical metric for tracking ice mass trends.
The dataset consists of systematic reprocessing of the entire CryoSat-2 archive to generate new L2-Swath products, increasing data sampling by one to two orders of magnitude compared with the operational L2 Point-Of-Closest-Approach (POCA) ESA product. In addition, the EOLIS dataset is joined with the ESA L2 POCA to generate monthly Digital Elevation Model (DEM) products. This dataset will further the ability of the community to analyse and understand trends across land ice globally.
As part of phase two, CryoTEMPO EOLIS was generated over land ice outside of the two largest ice sheets. The July, August and September 2021 point data is now available for three land-ice regions: Iceland, Svalbard, and the Canadian Arctic. Back processing has started and the data will be available for all months between 2011 and 2021 by the end of January. Going forwards, these point datasets will be published on a monthly basis.
The elevation change (m year-1) over the SARIn mode section of the Austfonna Ice Cap, Svalbard between 2011 and 2021 derived using the monthly EOLIS DEMs
In addition to the point data, monthly DEMs are being created for the Vatnajokull and Austfonna ice caps. These DEMs contain a pixel level uncertainty value, allowing the user to refine the pixels used based on the magnitude of uncertainty.
Following on from these regions, the Southern Andes, Greenland Periphery, Antarctica Periphery, Alaska and Russian Arctic point data will be going live in December with the Himalayas following in January. All back processed data will be available before the end of March.