Subglacial lakes are one of Antarctica’s most intriguing features. Hundreds of them have been identified over the decades, mostly through radio-echo sounding, an airborne technique that bounces radar pulses through the ice to map the bed beneath, and through satellite altimetry, which tracks the height of the ice surface over time. When a subglacial lake fills or drains, the ice above it rises or sinks like a slow-motion piston, and altimeters such as those flown on the ICESat and CryoSat missions have used this signal to catalog lake activity across the continent. Yet these instruments have a fundamental limitation: their spatial and temporal resolution is too coarse to reliably capture small lakes or events that unfold quickly. A lake spanning a few dozen square kilometers that empties over months can slip between the cracks of a global observing system designed to monitor continental-scale change.

The new study tackles that blind spot with a technique called double-differential interferometric synthetic aperture radar, or DDInSAR. Interferometric SAR, or InSAR, works by comparing the phase of radar signals returned to a satellite on successive passes over the same ground. Because the phase differences encode tiny changes in the distance between the satellite and the surface, InSAR can map surface deformation with centimeter or even millimeter precision across wide swaths of territory. Differential InSAR, or DInSAR, applies this principle to measure surface elevation change between two dates. DDInSAR goes one step further: it takes the difference between two DInSAR interferograms, which cancels out long-wavelength errors and isolates the localized deformation signal produced by a discrete event such as a lake draining beneath the ice.

To apply this method to the Kronshtadskiy lake, the researchers drew on imagery from the European Sentinel-1 radar satellites acquired between 2016 and 2021. Sentinel-1 revisits the same location every 24 days in its standard polar acquisition pattern, and by combining pairs of images with that temporal baseline the team generated a stack of DInSAR interferograms. From these they produced a total of 77 DDInSAR interferograms, each one capturing the incremental surface deformation over a 24-day window. Stacking and analyzing this dense time series allowed the researchers to reconstruct how the ice surface above the lake evolved year by year, something neither radio-echo sounding nor conventional altimetry could achieve at this level of detail.

The results show a dramatic and unambiguous event. The lake, which has a circular shape and covers an area of 61 square kilometers, underwent rapid drainage that produced pronounced subsidence of the overlying ice. At the center of the lake, the total subsidence reached 6.37 meters. Most of that sinking occurred during 2016 and 2017, when the surface dropped at a rate of 2.54 meters per year. The pace then fell off sharply, slowing to 0.88 meters per year in 2018 and to less than 0.30 meters per year during 2019 through 2021. That pattern, a burst of rapid water loss followed by a long tail of diminishing subsidence, is consistent with a lake emptying its water inventory and then stabilizing as the outflow tapered off.

Translating the measured surface deformation into a water volume, the team calculated that the drainage removed 78.0 million cubic meters of subglacial water. To put that number in perspective, it is enough water to fill tens of thousands of Olympic swimming pools, all of it moving through a plumbing system that no one can see directly, sealed beneath hundreds or thousands of meters of ice. Where that water went, and through what channels, remains an open question that radar observations alone cannot answer, but the timing and magnitude of the event now provide hard constraints for models of how water moves beneath this sector of the East Antarctic Ice Sheet.

An important strength of the study is that the DDInSAR results were cross-checked against independent satellite altimetry. Data from CryoSat-2, a European radar altimeter mission, and from ICESat-2, NASA’s laser altimeter, both confirmed the overall subsidence trend observed in the interferograms. This agreement matters because the two techniques have very different strengths and weaknesses. Altimetry provides precise point measurements of surface height but samples the ground sparsely, while DDInSAR provides dense spatial coverage of deformation but can be limited by loss of radar coherence in fast-flowing ice. The fact that the two independent records tell the same story gives confidence that the observed drainage is real and well quantified.

The location of the lake near the Amery Ice Shelf adds particular interest. This sector of East Antarctica feeds one of the largest ice shelf systems on the continent, and the ice in the region flows relatively quickly compared with the sluggish interior. Monitoring subglacial hydrology in fast-flowing polar environments has historically been difficult precisely because the rapid ice motion degrades the coherence of radar interferograms, blurring the very signals researchers want to isolate. The success of the double-differential approach here suggests that the technique can overcome that obstacle, opening the door to systematic monitoring of lake activity in dynamic outlet glaciers and ice shelf tributaries where subglacial water may influence flow speed.

Why does subglacial lake drainage matter beyond the novelty of watching a hidden lake empty? Water at the bed of an ice sheet acts as a lubricant, and changes in the distribution and pressure of that water can modulate how fast glaciers slide toward the ocean. Sudden drainage events can send pulses of water and altered basal conditions downstream, potentially affecting ice velocity and, over time, the discharge of ice into the sea. Understanding where, when, and how quickly subglacial lakes fill and drain is therefore a piece of the larger puzzle of predicting Antarctica’s contribution to sea-level rise. Techniques like DDInSAR, which can detect small and short-lived events that altimetry misses, are essential for building a complete picture of this hidden hydrological system.

The study also highlights the value of the Sentinel-1 mission for polar science. With its frequent revisit cycle, consistent acquisition strategy, and freely available data, Sentinel-1 has become a workhorse for monitoring the polar regions, and the 77 interferograms assembled in this work show how a multi-year archive can be mined for events that no one thought to look for in real time. As the radar archive grows and processing methods mature, researchers expect more discoveries of this kind: lakes filling and draining, channels opening and closing, and the slow breathing of an ice sheet whose plumbing system is gradually coming into focus. The drainage of Kronshtadskiy lake is a vivid reminder that Antarctica is not a frozen still life but an active hydrological landscape, one that satellites are now equipped to watch in fine detail.

Subject of Research: Satellite radar observation of the drainage of the Kronshtadskiy subglacial lake in East Antarctica

Article Title: Drainage of Kronshtadskiy subglacial lake in Antarctica observed by double-differential SAR interferometry

Article References: Moon, J., & Lee, H. (2026). Drainage of Kronshtadskiy subglacial lake in Antarctica observed by double-differential SAR interferometry. Scientific Reports. https://doi.org/10.1038/s41598-026-75829-x

Image Credits: AI Generated

DOI: 10.1038/s41598-026-75829-x

Keywords: Antarctica, subglacial lake, Kronshtadskiy lake, DDInSAR, SAR interferometry, Sentinel-1, Amery Ice Shelf, East Antarctic Ice Sheet, CryoSat-2, ICESat-2, subglacial hydrology, surface subsidence

The central argument of the paper, led by Jessica Scheick of the University of New Hampshire and Anthony Arendt of the University of Washington’s eScience Institute, is that open access alone is not enough. Making data freely downloadable does not guarantee that anyone can efficiently analyze it. The authors describe a paradigm shift in mindset: instead of a data provider building systems in isolation and then handing them to users, mission organizations should co-create data formats, software tools, and communities with the researchers they serve. This means involving external research and software specialists from the very beginning of mission planning, not after a satellite has already launched and its data formats are locked in.

The ICESat-2 mission illustrates both the problem and the promise of this approach. The satellite’s Advanced Topographic Laser Altimeter System, or ATLAS, is a photon-counting instrument that measures surface height by timing the flight of individual laser photons from the spacecraft to Earth. Its most basic geophysical product, ATL03, contains nearly a thousand variables per file organized across six beams, with roughly 300 gigabytes of data spread across more than 200 files each day. The mission archives most products in Hierarchical Data Format 5, or HDF5, a format prized for its metadata and compression but poorly matched to modern cloud-based access patterns. Researchers who wanted to study a specific region were forced to download enormous swaths of data organized by satellite flight path and then subset them locally, wasting storage, processing time, and money.

The turning point came through community gatherings. At the first hands-on ICESat-2 workshop in 2019, participants discovered that the available data access tools were rigid and difficult to customize, and they spent days writing their own scripts just to reach the data. That friction sparked a deeper collaboration between users and the National Snow and Ice Data Center, the NASA archive responsible for ICESat-2. With mission funding for annual hackathon-style events, the partnership produced open-source libraries such as earthaccess, which simplifies NASA data search and authentication, and icepyx, tailored to ICESat-2 workflows. The community also built SlideRule Earth, a cloud-based system that processes raw laser returns on demand, and CryoCloud, a shared computing platform for the cryosphere research community.

Perhaps the most striking technical payoff came from rethinking file formats. During the 2023 ICESat-2 Hackweek, staff from the data center, the HDF Group, and the mission’s processing team tested a cloud-optimized version of HDF5 for the mission’s seventh data release. The result was dramatic: access times to ICESat-2 data in the cloud dropped by at least an order of magnitude in every case tested, and in the worst scenarios fell from roughly twenty minutes to about thirty seconds. The innovation was quickly adopted by the NASA-ISRO Synthetic Aperture Radar mission, launched in July 2025, showing how improvements born in one mission’s community can ripple across the entire Earth science enterprise.

Several of the ten rules address the social infrastructure that makes such technical wins possible. The authors call for regular community-building and educational gatherings, particularly hackweeks modeled on the University of Washington eScience Institute’s format, which blends short-format training with collaborative project work. They also urge missions to fund persistent shared computing environments rather than temporary workshop hubs. CryoCloud, operational since October 2022, offers users up to 16 CPUs, 128 gigabytes of RAM, GPU access, and 45 gigabytes of persistent storage, managed under a shared-responsibility model by the nonprofit 2i2c, which handles cloud engineering, security, and cost monitoring while researchers govern access. Because users keep their environments after events end, the effort invested in learning new tools continues to pay off in ongoing research rather than evaporating when a temporary hub is shut down.

Communication matters as much as computation. The paper recommends centralized, open, self-governed asynchronous spaces, such as Slack workspaces paired with the computing hubs, where data producers, software engineers, archive specialists, and science users can interact regardless of institution or time zone. Usage data from CryoCloud show that communication platform activity remained consistently high even during seasonal lulls in computing, signaling sustained collaboration. Centralizing these conversations also relieves a hidden burden: user support specialists in the ICESat-2 ecosystem previously had to monitor at least eight Slack organizations, five GitHub organizations, and countless email lists and web forms, a fragmentation that left users posting questions in the wrong places and answers buried where no one could find them.

The remaining rules tackle sustainability and standards. The authors argue that missions should fund developers and open-source contributors with dedicated staff time rather than relying on volunteer labor, which they describe as unsustainable and disproportionately burdensome to the most committed community members. They recommend building open, extensible, reusable tooling that plugs into the existing scientific software stack instead of reinventing bespoke systems for each mission, and they call for community-owned instructional resources, such as the ICESat-2 Cookbook and curated resource lists, maintained as living documents on non-institutional platforms. Crucially, they advocate formal roles for community managers and leaders, identified at the mission planning stage, to organize engagement, mentor newcomers, and coordinate development roadmaps across tools that might otherwise evolve in isolation.

The final rule addresses performance and reproducibility. The authors recommend that missions adopt cloud-native, analysis-ready standards from the outset, including consistent formats, metadata conventions such as the SpatioTemporal Asset Catalog and CF conventions, and shared benchmarks built around representative scientific use cases. Without such benchmarks, individual teams run incomparable optimization exercises on arbitrarily chosen data subsets, and their results cannot guide mission-wide decisions. The rise of artificial intelligence raises the stakes further: machine-learning workflows for automated feature extraction and large-scale model training demand fast, consistent, scalable data access that only cloud-optimized formats and rich machine-readable metadata can provide.

Taken together, the ten rules sketch a future in which Earth observation missions are designed not just for their instruments but for their users, with open collaboration codified into the mission lifecycle itself. The authors acknowledge that NASA already solicits community input through Early Adopter Programs and Science Definition Teams, but they argue these efforts have been volunteer-driven, uneven, and secondary rather than central to mission planning. Their proposal is to make co-creation a first-order planning tool, equipping Early Adopters with realistically sized synthetic data years before launch and embedding software experts in mission design decisions. If the ICESat-2 community’s experience is any guide, the payoff could be enormous: faster science, lower costs, tools that outlive their missions, and, ultimately, a greater return on the public investment in watching our changing planet from space.

Subject of Research: Improving the usability of Earth observation mission datasets through open, collaborative mission design

Article Title: Ten rules to increase the usability of earth observation mission datasets

Article References: Scheick, J., Barrett, A. P., Fair, Z., Katz, Z., Lopez, L., Neeley, A., Roberts, C., Smith, B., Snow, T., Wegener, R., & Arendt, A. (2026). Ten rules to increase the usability of earth observation mission datasets. Earth Science Informatics, 19(11), Article 186. https://doi.org/10.1007/s12145-026-02216-5

Image Credits: AI Generated

DOI: 10.1007/s12145-026-02216-5

Keywords: Earth observation, ICESat-2, NASA, open science, cloud computing, data formats, HDF5, hackweeks, community management, open-source software, CryoCloud, data usability