FutureEO benefits series – Monitoring Earth’s frozen frontiers in a changing climate • Oct 2025

Launched over 25 years ago, the FutureEO programme is at the core of the ESA Earth Observation activities. It pushes boundaries of Earth observation, delivering excellence in science, technology innovation, preparing for new operational missions and supporting scientists, policymakers, and society with the knowledge needed to protect our planet’s future in the domain of environment, climate change and sustainability.

From pioneering Earth Explorer missions to agile Scout satellites and AI-powered data solutions, FutureEO is ESA’s commitment to scientific excellence, societal resilience, and global cooperation.

FutureEO is structured around three defining pillars that provide a streamlined and centralised framework for ESA’s Earth Observation goals. They work together to ensure there is a smooth flow of information between projects, connecting innovative ideas with scientific objectives to inform and guide the development of missions from concept through to design and realisation.

From pole to pole, ESA’s FutureEO programme is transforming how we observe our planet’s frozen regions. By combining cutting-edge satellite missions with decades of climate research, FutureEO is revealing how ice, ocean, and land interact in a rapidly changing world. The examples contained in this article, from monitoring thinning Arctic Sea ice and thawing permafrost to uncovering hidden Antarctic lakes, are just the tip of the iceberg. Behind them lies a much broader effort to understand, predict, and adapt to the profound changes reshaping Earth’s cryosphere.

The Arctic is changing faster than anywhere else on Earth. Since the early 1980s, this once-frozen frontier has been warming at four times the global average, triggering dramatic transformations across its icy landscapes. At the heart of this transformation lies the rapid decline of sea ice; a thin yet vital barrier that regulates the exchange of heat, moisture, and gases between the ocean and atmosphere.

But studying this fragile region has never been easy. Covering up to 20 million square kilometres at its winter peak, the Arctic’s remoteness and extreme conditions make direct observations difficult. For decades, scientists relied mainly on surface measurements, which could only capture the extent of sea ice and not its thickness, which is key to understanding how the Arctic truly functions as Earth’s climate regulator.

That changed with the launch of the European Space Agency’s CryoSat-2 mission. Under ESA’s FutureEO programme, which pioneers next-generation Earth observation missions, CryoSat-2 was designed to do something no other satellite could by offering unprecedented coverage of the Arctic, including detailed measurements of ice thickness using a novel radar altimeter system.

Working in tandem with SMOS (Soil Moisture and Ocean Salinity), another FutureEO mission that measures thin sea ice and ocean salinity, CryoSat-2 has revolutionized our ability to monitor polar regions. Over the past decade, data from these satellites has shown a significant thinning in multi-year ice across the western Arctic, with some regions losing thickness at rates of up to 1.5 meters per decade.

The insights gained from these ESA’s science missions have fundamentally reshaped our understanding of the Arctic’s role in global climate systems and are helping scientists anticipate major tipping points, including the possibility of a future “Blue Ocean” event, when the Arctic Ocean could become ice-free, profoundly altering global climate patterns and impacting industries like shipping and fishing.

ESA’s Earth observation satellites’ monitoring extends far beyond sea ice. ESA’s Climate Change Initiative (CCI), a cornerstone of the programme, harnesses decades of satellite observations to build comprehensive, long-term climate data records. One of its key projects, Permafrost CCI, focusses on monitoring the Arctic’s frozen ground, which stores vast amounts of carbon. By 2100, 21% of Arctic permafrost settlements may face erosion damage, 45% affected by sea level rise, and 77% may sit on unstable, crumbling and subsiding ground (1). Through 20 years of satellite data, ESA’s Earth Observation technologies allow for the tracking of changes in temperature, carbon cycling, ecosystems, active layer thickness, and coastal erosion, which are essential parameters for assessing permafrost stability. These insights empower policymakers and communities to plan climate adaptation strategies, protect infrastructure, and manage environmental risks associated with permafrost thaw and greenhouse gas release.

But the story of frozen Earth doesn’t end with the Arctic. Deep beneath Antarctica, a new threat is emerging that underscores the complexity and interconnectedness of the cryosphere. Recent research using CryoSat data has revealed that hidden subglacial lakes can suddenly drain into the ocean, destabilizing ice shelves and accelerating ice-sheet loss.

In one striking case back in 2013, seven subglacial lakes, that were more than 2 km beneath Thwaites Glacier, all suddenly drained at the same time (2). They released around 7 cubic kilometres of freshwater into the Amundsen Sea. Following this event, scientists observed a doubling of melt rates at the Thwaites ice shelves, along with significant ice thinning and retreat of grounding lines (the boundary where ice transitions from grounded glacier to floating shelf). These discoveries highlight that Antarctica’s “plumbing system”, the network of hidden water channels beneath its ice, plays a far greater role in ice-sheet stability than previously thought. Until satellites like CryoSat provided precise elevation measurements, such changes were impossible to detect.

ESA’s FutureEO programme continues to push the boundaries of climate science, from the Arctic’s shrinking ice to the hidden lakes beneath the Antarctic Ice Sheet that threaten its stability. As our planet warms, the need for reliable, long-term climate data has never been greater. Through innovative technology, global collaboration, and a commitment to open science, ESA’s FutureEO programme is ensuring that we not only observe the changing Earth, but understand and adapt to it.

_{References
(1) Tanguy, R. et al. (2024) ‘Pan‐Arctic assessment of coastal settlements and infrastructure vulnerable to coastal erosion, sea‐level rise, and permafrost thaw’, Earth’s Future, 12(12). doi:10.1029/2024ef005013.}

_{(2) Gourmelen, N., Jakob, L., Holland, P.R. et al. The influence of subglacial lake discharge on Thwaites Glacier ice-shelf melting and grounding-line retreat. Nat Commun 16, 2271 (2025). https://doi.org/10.1038/s41467-025-57417-1}