The UK Centre for Polar Observation (CPOM) is presenting a range of scientific studies and research this week at the European Space Agency (ESA) Living Planet Symposium in Vienna.
On Monday, CPOM Co-Director for Science, Professor Mal McMillan, presented results from the first phase of the CLEV2ER project, which is designing and building Level-2 processor prototypes for land ice and inland water, supporting the scientific readiness of the Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) ahead of the mission’s operational phase.
But what is CRISTAL?
The European Space Agency (ESA) is currently preparing for the launch of the Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) in 2027. Set to be a considerable advancement for polar science, CRISTAL will be equipped with a dual-frequency Interferometric Radar altimeter for Ice and Snow (IRIS) – a first for a satellite mission – and a passive microwave radiometer. This will give it the capability to monitor ice-sheet elevation as well as sea ice thickness and the overlying snow depth.
The mission is designed with long-term monitoring in mind, with two identical satellites CRISTAL A and CRISTAL B, with B replacing A before its lifespan finishes to ensure continued data collection.
What’s cool about the IRIS altimeter?
IRIS operates at Ku-band (13.5 GHz) and Ka-band (35.75 GHz) frequencies, known as KuKa. Using both frequencies, this radar can measure snow depth and sea ice thickness at the same time. CRISTAL will be able to measure the thickness of sea ice, the snow that covers it and the elevation of the world’s ice sheets and glaciers ensuring improvement and continuity from the CryoSat-2 mission. This information will be further complemented by data from a Microwave Radiometer providing even more precise information on surface-type classification and snow layer properties.
The ability to assess the depth of the snow overlying sea ice will increase the accuracy of sea ice thickness data, with importance for better understanding polar ice dynamics and global climate. Monitoring the height of ice sheets will support studies on ice mass balance and sea level rise attributed to melting ice sheets.
CRISTAL A is currently having components added by Airbus, with the satellite developed initially by ACPO Technologies. Thales Alenia Space is developing the IRIS altimeter, and the microwave radiometer will be provided by NASA’s Jet Propulsion Laboratory. You can read more about CRISTAL on ESA’s website.
CPOM Postdoctoral Researcher Dr Karla Boxall (Lancaster University), will also present an overview of progress on the CLEV2ER project on Wednesday including details on analysis and improvements of the methodology used for uncertainty estimation, the retrieval of penetration depth from dual band altimetry, and the role of snowpack properties on penetration depth estimates.
Dr Karla Boxall said:
“CRISTAL’s advanced multi-frequency altimeter provides an exciting opportunity to measure snow depth and coverage, which will improve quality of sea ice thickness and ice sheet elevation data significantly compared to its predecessor, CryoSat-2. CRISTAL will also play a vital role in ensuring the long-term continuation of radar-derived ice elevation records.”
Working together with emerging technology to prepare for a changing future
It is vital for the scientific community to collaborate and build on existing observation and modelling capabilities to ensure the effective and sustainable use of emerging technologies.
The cryosphere is a critical system of our evolving planet where changes often foreshadow broader impacts across the Earth. Melting ice sheets are contributing to rising sea level, and the influx of cold meltwater is affecting our ocean circulation systems, impacting our weather. Government agencies therefore need comprehensive and timely information to plan effectively.
In recent decades our ability to assess the polar regions has improved significantly due to satellite missions such as ESA’s CryoSat-2 and NASA’s ICESat and ICESat-2, along with advancement of observation and computer modelling techniques used by scientists at CPOM. The development of the CRISTAL space mission, and its enhanced radar altimetry technology, will support governments and agencies across the world prepare for climate change, by providing continuous, accurate Earth Observation data to enhance climate models and their projections of future polar ice behaviour.
Image credit: ESA
