In 2024, we were very lucky to be able to catch up with women working in the field of Earth observation and modelling from across the world at the ESA/NASA Cryo2ice conference in Iceland.
Ahead of International Women’s Day 2025 coming up this Saturday, we gathered some of the perspectives shared with us on the importance of studying and understanding the Earth, what it’s like working in this area of science and why it’s important to share scientific understanding with the world- as well as encouraging words for women and girls thinking of pursuing a career in science.as well as encouraging words for women and girls thinking of pursuing a career in science.
Thank you to our interviewees for taking part in this video: CPOM Principal Investigator: Sea Ice Earth Observation, Rosemary Willatt (UCL), Anny Cazenave (LEGOS), CPOM Director for Knowledge Exchange, Sammie Buzzard (Northumbria University), Liza Wilson (University of Iceland/Fulbright Commission Iceland), Rachel Tilling (NASA), Bryony Freer (Scripps Institute of Oceanography) and Helen Fricker (Scripps Institute of Oceanography).
A special thanks must also go to the ESA and NASA Cryo2ice team, who facilitated many of the interviews included in this video.
Environmental tipping points occur when warming temperatures lead to changes in the climate system which pass a threshold and become irreversible. Passing these points will lead to changes to sea level, ocean circulation and our weather, something world leaders need to plan for in advance. That’s why it’s vital to monitor for signs we are coming close to and passing these tipping points.
Combining observation and modelling expertise with innovative sensing systems, the programme aims to develop sensing systems for monitoring the Earth’s ice and oceans and place these systems in locations such as the Greenland Ice Sheet and the Subpolar Gyres (ocean circulation systems which sit under an area of constant low atmospheric pressure); both of which have been identified as crucial climate tipping points.
The programme will also look at developing improved models (computer simulations) to produce more robust and accurate predictions of these tipping points and the potential impact on the planet.
The programme is made up of 27 international teams of experts in climate science, maths, computer science, statistics, optics, photonics, and nuclear physics – bringing together this expertise to develop the best possible early warning system for these climate tipping points.
CPOM members are supporting three of these teams:
CryoWatch: Aims to progress the development of affordable, solar-powered, High Altitude Pseudo Satellites (HAPS), to be stationed in the stratosphere for persistent monitoring of polar regions. Led by Steve Tate (Voltitude), the team includes CPOM Co-Director of Science, Professor Mal McMillan.
OptimISM: A Next-Generation Framework for Ice Sheet Modelling. Led by Trystan Surawy-Stepney (University of Leeds), the team includes CPOM Principal Investigator: Land Ice Modelling, Dr Steph Cornford (University of Bristol).
PROMOTE: Progressing Earth System Modelling for Tipping Point Early Warning Systems. Led by Reinhard Schiemann (University of Reading and National Centre for Atmospheric Science), the team includes CPOM Principal Investigator: Land Ice Modelling, Dr Steph Cornford (University of Bristol).
It is said that Ernest Shackleton advertised ‘men wanted’ for ‘hazardous journey, small wages, bitter cold, long months of complete darkness, constant danger’ ahead of his 1914 Antarctic expedition which ended in the loss of his ship. Back then polar exploration and research was seen as an exclusively male occupation, even though women had been involved since as early as the 19th century. Women were often formally blocked from joining expeditions to the Arctic and Antarctic.
Times have certainly changed since then. During the last century intrepid and tenacious women led the way in shattering this ice ceiling. Fast forward more than a century after Shackleton’s infamous advert to 2025 and women scientists are participating in and leading field research projects across the cryosphere.
The UK Centre for Polar Observation and Modelling, brings together Earth Observation experts with modellers, to provide robust and accurate measurements of the Earth’s ice from the past and present, as well as projections for the future to help with world prepare for the changes a warming world might bring. Although we use satellite data in our work, Earth Observation often requires field-based observations to help verify satellite data, and so fieldwork is still an important piece of the puzzle when researching the polar regions, providing our scientists with wonderful opportunities to visit these incredible and rapidly changing environments.
DEFIANT (Drivers and Effects of Fluctuations in sea Ice in the ANTarctic) is a NERC project aimed at studying sea ice in the Southern Ocean and how it affects the wider climate system. CPOM’s Dr Inès Otosaka and Dr Isobel Lawrence and CPOM Director Professor Andrew Shepherd joined a fantastic team of scientists from BAS and DTU, to visit Antarctica to verify data collected on Antarctic sea ice by satellites.
Image credit: Professor Andrew Shepherd
Inès said (in this blog she wrote at the time) that ‘it was incredibly rewarding to see all the work that had been done over the months preceding the actual fieldwork come to fruition’. Although field work can be an exhausting experience, there was still time to enjoy the spectacular location with the team being ‘lucky enough to spot some penguins, seals, and even a pod of orcas.’
The team recorded this brilliant Iceworld podcast with BAS (British Antarctic Survey) – have a listen to their experiences on this incredible expedition.
Inès also joined Andrew Shepherd, PhD Researchers Amy Swiggs and Dr Anne Braakmann-Folgmann (former PhD Researcher) on the European Space Agency’s (ESA’s) Cryo2ice campaign to Greenland in 2022 where they collected ice cores, verified LiDAR measurements and collected snow depth measurements for snow density calculations. Amy wrote this blog about the fieldwork adventure, if you want to read more about this.
More recently in September 2024, Amy and Inès were also part of a CPOM team that visited Iceland to study proglacial lakes with a drone, alongside PhD Researcher Natasha Lee, CPOM Director for Knowledge Exchange Dr Sammie Buzzard, Andrew Shepherd, PhD Researcher, Nitin Ravinder and Data Scientist, Ben Palmer. We made this short film about this campaign, showing the team in action.
Image: CPOM PhD Researcher Natasha Lee, setting up a drone, on the Iceland Fieldwork campaign 2024.
Getting the opportunity to do fieldwork at an early career stage often draws people to polar science. For Dr Rosie Willatt (CPOM PI) the opportunity to visit Antarctica as a PhD student was a turning point in her career, and ultimately led to her becoming a polar scientist. You can hear more about how Rosie became a polar scientist in this video.
Sammie Buzzard, a glaciologist who started out studying maths, has been part of numerous fieldwork expeditions, including measuring glaciers in the Arctic during her PhD. She will soon be visiting the Antarctic in 2025.
She said “Although we are still far from gender equality within the polar sciences it’s fantastic to see opportunities becoming available to those of all genders that wouldn’t have been even during the earlier years of my lifetime”.
Image: CPOM’s Sammie Buzzard, preparing equipment on the Iceland Fieldwork Campaign, 2024.
These are just some of the examples of CPOM women scientists leading, and working on, these important fieldwork projects across the Arctic and Antarctica.
As we strive to understand these complex regions, how climate changes affect them and in turn how these changes will impact the rest of the planet in the years to come, it’s fantastic to see women scientists playing a vital role following the years of exclusion they experienced in previous centuries.
On Tuesday 12 November 2024, scientists from the UK Centre for Polar Observation and Modelling took part in STEM Learning’s Protecting our Planet Day 2024, a fantastic day of live-streamed sessions from experts on what is being done to protect our planet from space, and on Earth.
More than 150,000 people, including classrooms full of interested teachers and pupils, joined to learn more about climate change and how they can pursue a career in STEM.
Global warming is driving the rapid melting of the Greenland Ice Sheet, contributing to global sea level rise and disrupting weather patterns worldwide. Because of this, precise measurements of its changing shape are of critical importance for adapting to climate change.
Now, scientists from the UK Centre for Polar Observation and Modelling have delivered the first measurements of the Greenland Ice Sheet’s changing shape using data from ESA’s CryoSat and NASA’s ICESat-2 ice missions.
Although both satellites carry altimeters as their primary sensor, they make use of different technologies to collect their measurements. CryoSat uses a radar system to determine Earth’s surface height, while ICESat-2 uses a laser system for the same task.
Although radar signals can pass through clouds, they also penetrate the ice sheet surface and have to be adjusted to compensate for this effect. Laser signals, on the other hand, reflect from the actual surface but cannot record when clouds are present. The missions are therefore highly complementary, and combining their measurements has been a holy grail for polar science.
A new study from scientists at the CPOM and published today in Geophysical Research Letters, shows that CryoSat and ICESat-2 measurements of Greenland Ice Sheet elevation change agree to within 3% of the changes taking place.
This confirms that both satellites can be combined to produce a more reliable estimate of ice loss than either could achieve alone. It also means that if one mission were to fail, the other could be relied upon to maintain our record of polar ice change.
Between 2010 and 2023, the Greenland Ice Sheet thinned by 1.2 m on average. However, much larger changes occurred across the ice sheet’s ablation zone where summer melting exceeds winter snowfall; there, the average thinning amounted to 6.4 m.
Image credit: Professor Andrew Shepherd (Northumbria University)
The most extreme thinning occurred at the ice sheets outlet glaciers. At Sermeq Kujalleq in west central Greenland (also known as Jakobshavn Isbræ), the peak thinning was 67 m, and Zachariae Isstrøm in the northeast the peak thinning was 75 m.
Altogether, the ice sheet shrank by 2347 cubic kilometres across the 13-year survey period – similar to the amount of water stored in Africa’s Lake Victoria. The biggest changes occurred in 2012 and 2019, when the ice sheet shrank by more than 400 cubic kilometres because of extreme melting in those years.
Greenland’s ice melting also has profound effects on global ocean circulation and weather patterns. These changes have far-reaching impacts on ecosystems and communities worldwide. The availability of accurate, up-to-date data on ice sheet changes will be critical in helping us to prepare for and adapt to the impacts of climate change.
“We are very excited to have discovered that CryoSat and ICESat-2 are in such close agreement,” says lead author and CPOM researcher Nitin Ravinder. “Their complementary nature provides a strong motivation to combine the data sets to produce improved estimates of ice sheet volume and mass changes. As ice sheet mass loss is a key contributor to global sea level rise, this is incredibly useful for the scientific community and policymakers.”
The study made use of four years of measurements from both missions, including those collected during the Cryo2ice campaign, a pioneering ESA-NASA partnership initiated in 2020. By adjusting CryoSat’s orbit to synchronise with ICESat-2, ESA enabled the near-simultaneous collection of radar and laser data over the same regions.
This alignment allows scientists to measure snow depth from space, offering unprecedented accuracy in tracking sea and land ice thickness.
Tommaso Parrinello, CryoSat Mission Manager at ESA, expressed optimism about the campaign’s impact: “CryoSat has provided an invaluable platform for understanding our planet’s ice coverage over the past 14 years, but by aligning our data with ICESat-2, we’ve opened new avenues for precision and insight.
CryoSat Image Credit: European Space Agency
“This collaboration represents an exciting step forward, not just in terms of technology but in how we can better serve scientists and policymakers who rely on our data to understand and mitigate climate impacts.”
“It is great to see that the data from ‘sister missions’ are providing a consistent picture of the changes going on in Greenland,” says Thorsten Markus, project scientist for the ICESat-2 mission at NASA.
“Understanding the similarities and differences between radar and lidar ice sheet height measurements allow us to fully exploit the complementary nature of those satellite missions. Studies like this are critical to put a comprehensive time series of the ICESat, CryoSat-2, ICESat-2, and, in the future, CRISTAL missions together.”
ESA’s CryoSat continues to be instrumental in our understanding of climate related changes in polar ice, working alongside NASA’s ICESat-2 to provide robust, accurate data on ice sheet changes. Together, these missions represent a significant step forward in monitoring polar ice loss and preparing for its global consequences.
£8.4M has been awarded to the British Antarctic Survey and the Centre for Polar Observation and Modelling to deliver the next 5 years of their long-term polar science activities. The UK Polar Research Expertise for Science and Society (PRESCIENT) programme provides UK national capability (science, such as ongoing datasets and models, which underpins wider scientific research) to understand the impacts of environmental stressors, such as rising global temperatures on polar marine ecosystems. PRESCIENT will also measure and predict polar ice sheet contributions to global sea level rise and extend and improve measurements of changes to polar sea ice.
Announced today the funding is part of £101 million investment by the Natural Environment Research Council, part of UK Research and Innovation, in the UK’s network of leading environmental science research centres to support large-scale environmental observations, modelling and analysis, and research capabilities through innovations in platforms, sensors and data science. These data are crucial for managing natural resources, biodiversity, human health and building our understanding of and resilience to environmental hazards and climate change. It underpins science across the UK’s environmental research sector and supports critical scientific advice to government.
National capability is research funding which, unlike shorter term projects, can span decades and provides ongoing support for large-scale, complex scientific projects of national significance, informing strategic needs and decision-making of the country. Using techniques such as satellite altimetry to study ice motion and the polar oceans, CPOM incorporate the results into models used across the polar research community. CPOM’s data sets and models have been developed and maintained for almost a quarter of a century, and the long-term maintenance of this capability helps provide robust understanding and insights of the cryosphere.
CPOM also contribute to a range of interdisciplinary multi-centre National Capability research projects including CANARI, BIOPOLE, and TerraFIRMA, which have been running since 2022, offering satellite derived estimates of aspects of the cryosphere (such as ice thickness, floe size and sea height), as well as developing advanced simulations. The longevity of our datasets, and the accuracy of our models mean we have a broader view of past and possible future changes. By contributing to projects such as the previous multi-centre National Capability project UKESM (UK Earth System Model), integrating ice sheet model and advanced sea ice physics into the system, we can produce robust projections of ice sheet instability and Arctic sea ice loss, thereby informing sea level rise predictions. Our PRESCIENT programme with BAS continues this work into 2029.
This funding has been awarded from NERC’s National Capability Single Centre Science initiative, one of the UK’s largest environmental science investment programmes.
New publication in Nature Communications introduces GPSat, a tool that helps process constantly changing satellite data, more quickly and efficiently than older methods. This tool can help scientists better monitor changes in sea ice over time and help improve predictions for sea-level changes.
GPSat can produce detailed maps of Arctic sea ice, filling in any gaps in the satellite data and can produce data more than 500 times faster than older methods while maintaining accuracy (demonstrating less than 4 mm difference on the derived freeboards on average).
The paper, authored by William Gregory (Princeton) and involving CPOM co-authors Isobel Lawrence (ESA), Carmen Nab (UCL) and Michel Tsamados (UCL), was published on 28 August 2024 in Nature Communications.
Author information: Gregory, W., MacEachern, R., Takao, S. et al. “Scalable interpolation of satellite altimetry data with probabilistic machine learning”. Nat Commun 15, 7453 (2024). https://doi.org/10.1038/s41467-024-51900-x
CPOM Director Prof Andrew Shepherd and CPOM Assistant Director Sammie Buzzard discuss the importance of protecting our polar regions and how we monitor them here at CPOM in this educational video from the Protecting Our Planet 2023 event run by Stem Learning.
This week we watched along with many across the globe, as pioneer European satellite ERS-2 finally made its journey back to earth after almost 30 years monitoring earth from the sky.
For many current and former CPOM scientists, this was an emotional moment, as the data from this satellite has made (and continues to make) an integral contribution to understanding the cryosphere. In fact, CPOM Director Professor Andrew Shepherd used ERS-2 data for his first paper 23 years ago ‘Inland Thinning of Pine Island Glacier, West Antarctica’ which used satellite altimetry and interferometry to show that the glacier ‘had thinned by up to 1.6 meters per year between 1992 and 1999’.
Part of the European Space Agency’s (ESA) earth observation programme, the revolutionary satellite was launched in April 1995 into a sun-synchronous polar orbit at an altitude of around 800 km, and was one of the most powerful and sophisticated satellites of its time.
Due to its three-axis stabilization it was able to point directly towards our planet and could observe most areas of the earth, using SAR (Synthetic Aperture Radar) to view land surfaces, polar ice and oceans, measuring ocean-surface temperature, sea winds and sea level changes via Radar Altimetry. On top of this it could also monitor ozone levels.
The data this satellite collected has been crucial in monitoring land surface changes, warming oceans, natural disasters, and importantly for the Centre for Polar Observation and Modelling – monitoring diminishing polar ice and sea-level rise. ERS-2 (and it’s twin ERS-1 launched a few years prior) paved the way for other programmes including the EU Space program’s Copernicus Sentinels and ESA’s CryoSat Earth Explore Mission, both of which continue to provide vital data for CPOM’s research. In fact, we are using ERS-2 data to extend our datasets further back in time, in order to create a fuller view of the evolution of the cryosphere over the last 30 years.
It was retired in 2011 and has been de-orbiting since then. Now it’s 16-year journey home is complete, broken and burned up in the atmosphere with the remaining parts landing safely in the ocean yesterday but even though the physical entity is gone, the data it produced, having been used for thousands of scientific papers, continues to provide information for scientists at ESA, CPOM and beyond.
During the melt season (typically from May to September) on the Greenland ice sheet, water collects in depressions on the surface of the ice, creating supraglacial lakes. If these lakes have enough water and the right conditions, they can crack open (hydrofracture) which allows water to flow from the ice surface down to the bedrock underneath, where it acts like a lubricant. These lakes on the Greenland ice sheet are incredibly important, but identifying exactly how deep they are using satellite data is difficult.
This research compares different ways of measuring the depth of these supraglacial lakes, using tools including a radiative transfer equation (RTE), ArcticDEM digital elevation models, and ICESat-2 photon refraction. The team of researchers led by CPOM PhD Researcher Laura Melling (Lancaster University) applied these methods to five lakes in southwest Greenland.
The paper examines the uncertainty in these estimates, which affects our understanding of the total lake volume and how that, in turn, can interfere with predictions about how fast the ice is moving. This work demonstrates how combining information from multiple different satellite sources can improve our ability to track meltwater on top of the Greenland Ice Sheet.
Authors include: CPOM PhD Researcher Laura Melling (Lancaster University), CPOM Associate Investigator Amber Leeson, CPOM Principal Investigator Malcolm McMillan (Lancaster University), CPOM Senior Research Associate Jennifer Maddalena (Lancaster University), Jade Bowling (Lancaster University), CPOM PhD Researcher Emily Glen (Lancaster University), Louise Sandberg Sørensen (Technical University of Denmark), Mai Winstrup (Technical University of Denmark), and Rasmus Lørup Arildsen (Technical University of Denmark).
