On Wednesday at the European Space Agency’s Living Planet Symposium 2025 we had a fantastic celebration of a very special satellite mission: CryoSat.

CryoSat-2 is very close to our hearts here at the UK Centre for Observation and Modelling (CPOM), due to the crucial role the intrepid Earth Explorer plays in gathering data on the Earth’s ice sheets, sea ice, ice shelves and glaciers. Without this information, we wouldn’t have made the significant leaps forward in polar and climate science over the last two decades.

In the session ‘Celebrating 15 Years of CryoSat for climate science’ led by Tommaso Parrinello (Aeolus and CryoSat Mission Manager, ESA) we heard from a range of scientists on the importance of this mission and how it has contributed to our understanding of the cryosphere, its impact on the wider Earth systems and sea level rise, as well as how it will continue to shape the future of climate science.

To mark this special occasion, we have put together this list of 10 cool things we love about CryoSat-2 from yesterday’s fascinating series of talks on the mission.

1. The idea for CryoSat was conceived by Sir Duncan Wingham, CPOM’s founding Director, but the first satellite was lost in a launch failure in 2005. Thankfully it was rebuilt and launched successfully five years later in 2010.
2. CryoSat’s original mission objectives were to monitor polar ice sheets and arctic sea ice, but today a large proportion of scientific papers using CryoSat data is on topics outside of the cryosphere, noted Andrew Shepherd in his presentation.
3. CryoSat has been instrumental in monitoring global ice losses! In 2021 a study led by CPOM’s Tom Slater showed that Earth is losing 1 trillion tonnes of ice each year. The Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) Project led by CPOM’s Inès Otosaka now produces annual assessments of ice sheet mass balance, taking advantage of CryoSat data alongside other satellite missions.
4. CryoSat even works on Canadian ice caps, said Professor Rene Forsberg! CryoSat can capture information on smaller ice caps and glaciers due to the advancement of the swath processing technique. Swath processing uses interferometry to map ‘broad swaths of surface elevation’ allowing for higher resolution (less than one kilometre) elevation measurements.
5. In 2023, CryoSat went global on glaciers! The first global assessment of global glacier mass change with radar altimetry was produced (Jakob & Gourmelen, 2023). This year the GLAMBIE project produced updated figures on glacier loss showing that from 2000 – 2023 glaciers across the globe lost 6542 billion tonnes of ice, contributing 18 mm to global sea level rise.
6. CryoSat-2 and ICESat-2 are complementary! In a recent study led by CPOM’s Nitin Ravinder showed that CryoSat and ICESat-2 measured Greenland ice sheet elevation change measurements agree with each other to within 3%, confirming that results from these satellites can be combined to produce a more reliable view of ice sheets.
7. There is a CryoTEMPO product suite which uses CryoSat-2 data to produce easily accessible, user-friendly data products for a variety of thematic areas such as sea ice, land ice, polar oceans, coastal oceans and inland water.
8. CryoSat provides insights on sea level rise. Anny Cazenave (LEGOS) gave a wonderful overview on how CryoSat-2 has supported our understanding of sea level rise, sharing insights on altimetry-based sea level trends (2011-2022) AVISO.
9. There’s a CryoSat Companion now available through ChatGPT! This new AI assistant supports people in using and understanding the data. It even told us an icy joke during the presentation.
10. CryoSat is inspiration of the new CRISTAL mission due to launch in 2027. Set to be a considerable advancement for polar science due to it’s dual-frequency Interferometric Radar altimeter for Ice and Snow (IRIS).

But this is just the tip of the iceberg (sorry!). There’s still so much to learn from CryoSat, and you can do that by following updates from @esa_cryosat on X.

CryoSat’s journey is not over yet, by any means!

In the session ‘Outlook for ESA’s Earth Observation programmes’ at the European Space Agency’s Living Planet Symposium 2025, we heard from Josef Aschbacher, Director General of European Space Agency – ESA, Simonetta Cheli – Director of Earth Observation at ESA, Charles Galland, Policy Manager at ASD-Eurospace, and Andrew Shepherd, CPOM Director (Northumbria University) on the planned funding proposal to EU Member States due later this year. Andrew stood as a representative of the scientific community due to his long-standing collaborative relationship with the European Space Agency and over two decades of experience of EO scientific research.

Josef Aschbacher said: “We are delivering data and services for citizens. Earth Observation is providing a lot of this: services for farmers, for health practitioners, for city planners, for forestry, for aviation, for disaster management to provide information in case of crises.”

Simonetta Cheli said: “There’s an increase of the relevance of space in support of resilience, in support of security, in support of defence needs, and there is also a geopolitical context where EO could provide a further opportunity to increase overall, not just at ESA level, the European leading role that we have in the sector on climate, on sustainability, and the current proposal is a really bold step in that direction.”

Charles Galland said: “This is a strategic investment in Europe’s industrial future. ESA must remain a scientific and technical leader but also increasingly become an economic and market enabler. Industry is ready for that.”

Andrew Shepherd said: “The science is what underpins action, by other people or by ourselves to address the problems the climate is facing and to adapt to the world that we are going to be living in.”

Andrew’s presentation highlighted that:

🌐 Climate science is founded on EO
🛰️ Science underpins action
🌳 Action is the green economy
🌍 Europe is leading the way
🚀 FutureEO is essential

This fascinating session was part of the Living Planet Symposium 2025.

🔗 For the full schedule visit: https://lps25.esa.int/

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.

• For more updates on CPOM at LPS25 follow us on X, Bluesky, Instagram and LinkedIn.
• For the exciting full LPS25 schedule, visit the LPS website.

Image credit: ESA

The Environmental Audit Committee has released its report on the UK and the Antarctic environment featuring evidence from CPOM and colleagues from across the polar science community.

This inquiry explores the impacts of climate change in Antarctica and the role that UK science can play in understanding these changes and protecting the region.

Our evidence, submitted via two calls for evidence in 2024, highlighted:

• Changes in the Antarctic will have global consequences for people and animals.
• We will need to adapt to significant impacts from sea level rise in the coming years.
• The UK needs to commit to supporting long-term international collaborations between modellers, climate scientists, and remote sensing specialists to ensure we are fully prepared for these changes.
• There is an opportunity to improve observations through the United Nations Antarctica InSync programme.
• There is a requirement for governance of any future geoengineering schemes in the region.

Parliamentary inquiries are an important way academics can inform the UK Government about relevant scientific research and provide advice to influence policy decisions.

The can read the full report and supporting evidence on the UK Parliament website.

To find out more about how CPOM provides information for policymakers on our Research Impact pages.

Web Story Image Credit: Professor Andrew Shepherd