PICO
We propose an interactive PICO session format to encourage in-person dialog and random human interactions with the hope of fostering in-depth discussions and future scientific collaborations.
In recent years, a number of studies have focused on the mechanical impacts of sea-ice loss on Antarctic ice shelves. These impacts arise either through the potential buttressing provided by multi-year landfast sea ice or through increased ocean swell as pack ice diminishes. Increasing periods of sea-ice-free conditions near ice shelves also modify thermal forcing, as sea-surface temperatures seasonally increase. The number of sea-ice-free days has increased by around 50% at the eastern Getz Ice Shelf since the 1970s, to the point where it is virtually sea-ice-free throughout December and January each year, when solar insolation is at its highest. With the exception of the Ross Ice Shelf, no other major ice shelf experiences comparable summer sea-ice-free conditions. We explore the calving processes along the eastern Getz Ice Shelf, with the underlying hypothesis that these processes will become increasingly relevant across Antarctica as sea ice continues to diminish.
The calving fronts of the eastern outlets of the Getz Ice Shelf have been retreating since the earliest satellite observations in the 1970s. This retreat is persistent and is characterised by advance during the winter months and retreat during the summer, with frontal ablation rates of around 650 m a⁻¹. This retreat has occurred despite no detectable changes in ice-shelf damage over the past 50 years, the absence of landfast sea ice, limited changes in ice velocity seaward of the grounding zone, and no recorded thinning in the outlet experiencing the most significant retreat. Surface profiles of the ice shelf reveal widespread evidence of rampart–moat structures, which are highly indicative of buoyancy-driven calving. Sea-ice-free conditions allow the ocean surface to heat up; this heat is sufficient to drive undercutting at the ice front, resulting in cliff retreat and the formation of an underwater foot, which in turn promotes buoyancy-driven calving, termed ‘footloose’ calving. In the case of the easternmost outlet of the Getz Ice Shelf, retreat is already progressing into its embayment; in the coming years, this will result in a loss of buttressing, acceleration, and a change in the dynamic state of the ice shelf.
Nearly all other Antarctic ice shelves remain encased by sea ice during the summer. Many of these ice shelves, particularly those in regions such as Dronning Maud Land, flow at only ~200 m a⁻¹, meaning that a similar frontal ablation rate of 650 m a⁻¹ would be highly significant. As sea ice diminishes and this mechanism becomes increasingly important, we cannot rule out widespread retreat of Antarctica’s ice shelves driven by a process not currently incorporated into ice-sheet models.
How to cite: Miles, B., Crawford, A., and Homer, N.: Multi-decadal ice shelf retreat driven by ocean wave erosion in the absence of sea-ice, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19807, https://doi.org/10.5194/egusphere-egu26-19807, 2026.
Antarctic ice shelves have been losing mass at an increasing rate in recent decades. This process is missed in most climate models. Recent studies added extra freshwater along the Antarctic coast to investigate its potential effects. However, these studies used either model simulated or uniformly distributed freshwater inputs, so that climate impacts of realistic, time- and space-varying meltwater remain uncertain. Here, we investigate implications of the recent change in basal melt rates from 93 Antarctic ice shelves from the 1990s to 2006–2016 (223 Gt yr-1 on average) on Southern Ocean climate using a fully coupled model. The most prominent response is significant increased sea ice coverage in the northern Amundsen Sea and decreased sea ice coverage in the northern Weddell Sea. The northern Amundsen Sea experiences sea surface and near-surface atmospheric cooling and a strengthened Amundsen Sea Low, while the northern Weddell Sea exhibits warming and above-normal sea-level pressure. In the Amundsen Sea, both oceanic thermodynamic and atmospheric dynamical effects contribute to sea ice growth during the freeze-up season, with atmospheric dynamics playing a dominant role during the melting season. In contrast, sea ice decline in the Weddell Sea is primarily driven by oceanic warming during the freeze-up season and atmospheric circulation anomalies during the melting season. Our results highlight the critical role of atmospheric circulation changes in shaping the contrasting sea-ice and temperature responses in the Amundsen and Weddell Seas and underscore the importance of representing realistic ice-shelf basal melt in coupled climate models to better understand Southern Ocean climate variability.
How to cite: Zhu, Z., Liu, J., Liu, Y., Martin, T., Song, M., Yang, C.-Y., Chai, W., and Yang, Q.: Implications of realistic Antarctic ice shelf basal melting during 2006–2016 on Southern Ocean climate, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15645, https://doi.org/10.5194/egusphere-egu26-15645, 2026.
Basal terraces occur at the base of Antarctic ice shelves. They are characterized by near-vertical walls, often several tens of meters high, which are interconnected by planar, quasi-horizontal, smooth interfaces. Basal terraces have been observed on numerous warm-cavity ice shelves, particularly close to the grounding zone. Their formation has been linked to preferential, ocean-induced horizontal melting at the vertical walls and subdued melting at the horizontal interfaces. Often they are identified as basal melting hot-spot with melt rates much higher than the ice-shelf wide average. However, direct confirmation of these processes on seasonal to yearly timescales do not yet exist.
Here, we present a comprehensive ground-based radar dataset that images the three-dimensional geometry of a basal-terrace field near the grounding zone of the cold-cavity Ekström Ice Shelf. The dataset consists of two time slices spaced one year apart and is analyzed in an Eulerian framework. The radar data are complemented by continuously measuring ApRES thickness measurements, which are integrated into the 3D geometry.
We find that basal melt rates at the horizontal ice face in the nadir direction are approximately one order of magnitude smaller than melt rates inferred from off-nadir reflections, which originate from a nearby inclined interface. All melt rates are with a max of several meters per year small compared to other studies. There is little subseasonal to seasonal variability. Apart from overal thinning, virtually no discernible changes in the 3D geometry are observed over the annual timescale. In airborne radar data, basal terraces occur preferentially near the grounding zone and disappear further seaward.
Taken together, our data support findings from previous studies that ocean-induced melt rates vary significantly over sub-kilometer distances. However, our results also suggest that basal terraces can enter a dormant mode in which they passively advect seaward and maintain a stable geometry without the need for persistently high basal melt rates.
How to cite: Drews, R., Noll, J., Muhle, L.-S., Wild, C. T., Oraschewski, F., Eisen, O., and Schlegel, R.: Yearly evolution of Basal Terraces in the cold-cavity of Ekström Ice Shelf in East Antarctica, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6553, https://doi.org/10.5194/egusphere-egu26-6553, 2026.
The Antarctic Ice Sheet (AIS) is a major contributor to future global sea level rise. Approximately half of the surface mass gain is offset by ocean-induced basal melting, highlighting the critical role of ice-ocean interactions. Uncertainty in projections of AIS evolution remains strongly linked to how basal melting is represented and calibrated in ice-sheet models, together with divergent future climate forcing scenarios.
In this study, we use a circum-Antarctic high-resolution configuration of the Úa ice-sheet model to conduct a series of 360 hindcast simulations (spanning 2000-2020) to quantify uncertainties and sensitivities in modelled ice-shelf melt. The ensemble covers a range of ice rheology and basal sliding parameters, as well as multiple basal melt parameterizations (quadratic, PICO and plume) and a physically plausible range of parameter choices for each parameterization.
Whereas previous studies have calibrated basal melt parameters using fixed ice-sheet geometries or relied primarily on basal melt observations alone, this study presents two advances: 1) ice-ocean feedbacks were included in the calibration through temporally evolving basal melt rates, and 2) simulated changes in ice velocity and thickness over the hindcast period were validated against remote-sensing data.
After calibration, model performance improves in the representation of both basal melt rates and ice-dynamic response patterns. For most basal melt parameters, the posterior distributions exhibit clear localization relative to the prior, indicating well-defined optimal parameter values. The resulting calibrated parameter ranges therefore provide a more robust foundation for future long-term projections of AIS evolution and its contribution to global sea-level rise. Notably, these optimal parameter values differ from those obtained using calibration approaches based on fixed ice-shelf cavities or basal-melt observations alone. We also examine regional variability in calibration results. The relative performance of basal melt parameterizations differs between Antarctic sectors, while optimal parameter ranges within each parameterization remain broadly consistent with the Antarctic-wide calibration.
How to cite: Qin, Q., Rydt, J. D., Coulon, V., and Pattyn, F.: Historical Calibration of Basal Melt Parameters in a circum-Antarctica Ice-Sheet Model, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12502, https://doi.org/10.5194/egusphere-egu26-12502, 2026.
Basal melt rate in the grounding zone is one of the single most important and least-well constrained parameters in modeling the rate and amount of future sea level rise. Sub-ice shelf basal melt rate can be calculated by continuity of mass provided that local ice thickness is well known. However, continent-wide maps of ice thickness that rely on the hydrostatic assumption may underestimate ice thickness near the grounding line. Here, we jointly invert for ice shelf thickness and effective Young’s modulus in the grounding zones of three basins on the Ronne-Filchner Ice Shelf (FRIS or RFIS) based on an elastic beam model of the tidal flexure of ice shelves to make new estimates of basal melt rate in the grounding zone. We show that uncertainty in ice thickness gradient drives uncertainty in the spatial pattern of basal melt rate: adding, eliminating, or moving oceanographic features such as freeze-on bands. This has implications for the set of admissible parameterizations of basal melt rate in models that project the evolution of the Antarctic Ice Sheet in the coming decades and centuries.
How to cite: Elgart, F. and Minchew, B.: Toward new maps of basal melt rate in grounding zones with tidal flexure from ICESat-2, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7168, https://doi.org/10.5194/egusphere-egu26-7168, 2026.
More than 80% of the grounded ice of the Antarctic ice sheet drains into the ocean through ice shelves. Loss of these ice shelves could cause an increase of the discharge of grounded ice which would lead to additional sea-level rise. Roughly half of the ice shelves’ mass is eventually lost through melting from the underside, where the ice gets in contact with warmer ocean waters. However, estimating these basal melt rates is notoriously difficult. Here, we present a novel methodology for calculating the melt rates by assimilating remotely derived estimates of surface velocities, ice sheet thickness, surface elevation changes and modelled surface mass balance using an ice sheet model (Úa). This methodology allows for a less noisy, physically consistent estimate of the ice mass divergence, and weighs each of the input data with their uncertainty. As a case study, we apply our method to the Ross ice shelf and find that the melt rates are highly spatially variable.
How to cite: Brils, M. and Gudmundsson, H.: Inferring basal melt rates underneath the Ross Ice Shelf using data assimilation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13590, https://doi.org/10.5194/egusphere-egu26-13590, 2026.
The Antarctic Ice Sheet is a major contributor to present-day sea-level rise, with most mass loss occurring through ice shelves that regulate upstream ice flow via buttressing effect. Recent widespread ice-shelf thinning, enhanced calving, and structural weakening underscore the need for long-term observations to understand ice-shelf stability and potential tipping behavior. Pine Island Glacier and its ice shelf, located in the Amundsen Sea sector of West Antarctica, have experienced sustained acceleration, thinning, and retreat since the 1970s, making this system an ideal natural laboratory for investigating ice-shelf dynamic responses to climate forcing.
Here, we investigate the dynamic evolution and stability of the Pine Island Ice Shelf (PIIS) from 2014 to 2025 using multi-source satellite remote-sensing data. While the dynamics for the PIIS for the last decade are dominated by accelerating flow, the velocity time series also reveal a deceleration of the central PIIS between 14 March 2022 and 20 January 2023. Piglet Glacier, a major tributary of the PIIS, also experienced two distinct deceleration periods between 2023 and 2025. Our analysis demonstrates that ice flow in the central PIIS and Piglet Glacier is highly sensitive to mechanical coupling along shear margins, modulated by variations in the state and configuration of dense ice mélange. In the northern sector of the ice shelf, sustained thinning, loss of pinning points, rift propagation, and a major calving event collectively indicate progressive structural weakening, despite a limited dynamic response to date.
Overall, our observations indicate a transition toward increased structural vulnerability across the Pine Island Ice Shelf. These findings provide new observational constraints on ice-shelf stability, grounding processes, and transient deceleration mechanisms, with important implications for ice-sheet modeling and future sea-level projections.
How to cite: Chien, Y., Zhou, C., and Riel, B.: Dynamic evolution and emerging structural vulnerability of the Pine Island Ice Shelf, West Antarctica from 2014 to 2025, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4638, https://doi.org/10.5194/egusphere-egu26-4638, 2026.
During the post-LGM, the West Antarctic Ice Sheet first retreated from deep-water troughs, followed by retreat from shallower-water banks. Deglacial succession from the troughs show a classic sequence from subglacial sediments deposited below fast-flowing ice streams, that transition upcore to sub-ice-shelf and open-marine sediments accumulated following grounding line and calving front retreat, respectively. Diatom assemblages in these sediments provide powerful evidence for making these environmental interpretations. For example, open-marine facies contain abundant Fragilariopsis curta, a sea-ice associated diatom. In comparison, deglacial successions for bank crests are poorly studied. Understanding bank stratigraphy is important because the formation of an ice rise would influence the pattern of deglaciation. Data acquired during expedition NBP2301/02 demonstrate that the Ross Ice-Shelf (RIS) was formerly pinned to Ross Bank, a broad shallow area in the central Ross Sea. Here, we evaluate the diatom assemblage data from four sediment cores from the shallow-water crest and deep-water flanks of Ross Bank. On the bank crest, the deglacial succession is a sand-rich residual glacial marine deposit. The diatom assemblage contains high to moderate percentages of sea-ice and permanently open-ocean species. These abundances suggests these winnowed products were derived from sediments that initially accumulated in distal sub-ice-shelf and/or open-marine settings. The downcore variations in diatom assemblage and abundance indicate that the intensity of winnowing on the bank was variable after the RIS unpinned. Understanding these processes is important as it can be used to constrain deglacial sequences and to identify reworked intervals in bank-crest core, which when combined with other evidence, can be used reconstruct the pattern and timing of ice shelf unpinning and other clues as to how the local deglacial conditions evolved.
How to cite: Meyne, R., Patterson, M., Leventer, A., and Bart, P.: Preliminary reconstruction of deglacial conditions at Ross Bank following the post-LGM collapse of the Ross Bank Ice Rise , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8787, https://doi.org/10.5194/egusphere-egu26-8787, 2026.
The rapid melting of polar ice sheets is one of the biggest unknowns in sea-level-rise models. The instability is not due to a single factor but emerges due to the complex coupling of thermodynamic forcing and mechanical response. This paper provided a review of the physical mechanisms governing these processes with an emphasis on the transition from surface melt to structural failure.
The authors analyze surface energy balance and latent heat release from the firn-ice aquifers instability in the ice sheet. We also investigate how these thermal anomalies become mechanical drivers, such as hydro-fracturing and basal lubrication, that reduce effective stress and accelerate ice flow. The link between Marine Ice Sheet Instability (MISI) hypothesis and purely atmospheric forcing is also discussed from continuum mechanics perspective.
By reviewing the existing literature through a physics view, this paper wants to identify the gaps in the current ice sheet models (ISM) in terms of stress transmission and fracture propagation parameterization. The purpose of this project is to lay the theoretical groundwork for a master’s thesis that aims to use a more integrated model of the non-linear response of ice sheets to climate warming.
How to cite: Kılınçoğlu, D., Yılmaz, İ. Ö., Akınoğlu, B. G., and Karaveli, A. B.: Understanding Ice Sheet Instability: A Review of Thermodynamic and Mechanical Drivers Behind Mass Loss, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10022, https://doi.org/10.5194/egusphere-egu26-10022, 2026.
The Northeast Greenland Ice Stream (NEGIS) drains through two major outlet glaciers: the 79 North Glacier (79NG) and Zachariae Isstrøm (ZI). Since the 2000s, these glaciers have exhibited contrasting behavior: while the ZI ice shelf has retreated dramatically and transitioned to a tidewater glacier, the 79NG ice tongue has remained relatively stable in extent despite significant thinning. The retreat and thinning of both glaciers have accelerated the upstream ice stream, with important implications for global sea level rise.
We present a novel coupled model that integrates the Ice-sheet and Sea-level System Model (ISSM) with the Finite volumE Sea Ice-Ocean Model version 2 (FESOM2). The ice sheet model domain encompasses the NEGIS region, while the global ocean model features enhanced mesh resolution on the Northeast Greenland continental shelf and explicitly resolves the ice shelf cavities of both 79NG and ZI. This coupling enables dynamic representation of ice sheet-ocean-sea ice interactions, including grounding line migration and ice geometry evolution.
A hindcast simulation spanning 2008-2023, forced by atmospheric reanalysis data, reproduces the observed calving front retreat at ZI with good fidelity, validating our modeling approach. Beyond validation, this experiment reveals that the rapid ZI retreat is driven primarily by internal ice dynamics rather than changes in oceanic forcing. We extend our analysis through climate projection simulations using atmospheric forcing from CMIP6 scenarios. Applying both low and high emission scenarios (SSP126 and SSP585), we are able to assess the possible future evolution of these glaciers until the end of this century.
How to cite: Wekerle, C., Wolovick, M., Dong, Y., Rückamp, M., Timmermann, R., and Kanzow, T.: Evolution of the Northeast Greenland glaciers in a warming world, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17895, https://doi.org/10.5194/egusphere-egu26-17895, 2026.
The Greenland Ice Sheet is the fastest growing contributor to sea level rise, due to loss of ice from its marine-terminating outlet glaciers. One of the largest of these is Helheim Glacier, located in eastern Greenland. Recent observational work suggests that Helheim could be approaching a threshold beyond which it would undergo rapid retreat. Here, we present a modelling study investigating the stability of Helheim Glacier. We seek to establish whether such a threshold exists in the future evolution of this glacier, and whether a rapid retreat event would be reversible. We approach this by initialising the model to a steady state close to the present-day geometry of the glacier, then carrying out a series of experiments to test its stability in relation to changes in atmospheric and ocean forcing. Calving front positions at the ocean interface and mass balance at the surface are perturbed incrementally, and the system allowed to reach a new steady state after each perturbation. The forcing is then reversed in order to assess whether the resulting changes to the glacier’s position and dynamics are reversible. Our methodology is demonstrated in synthetic geometries representative of Greenlandic fjord environments, in which we find a hysteresis behaviour within the system such that after a retreat of the ice front, readvance will not occur along the same pathway when the forcing is reversed. Initial results suggest that such behaviour is also present within the Helheim system.
How to cite: Barnes, J. and Gudmundsson, H.: Investigating the stability of Greenland’s outlet glaciers, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1898, https://doi.org/10.5194/egusphere-egu26-1898, 2026.
We analyze the temporal evolution and kinematics of a large mega-crevasse situated in the northern sector of Jakobshavn Isbræ, West Greenland, roughly 50 km north of the glacier’s main flowline. Our study relies on continuous surface-displacement measurements collected by a dense array of 18 permanently operating GNSS stations deployed across and around the crevasse system. These stations recorded ice-surface motion at high temporal resolution over nearly two years, enabling us to capture both seasonal trends and short-term dynamical fluctuations. The resulting displacement time series reveal how strain, opening rates, and relative motion across the crevasse evolved through time, providing new insight into the mechanisms controlling crevasse initiation and growth in this highly dynamic sector of the ice sheet. Fourteen of the GNSS stations are arranged along a profile oriented perpendicular to multiple crevasses, allowing us to quantify both rapid deformation associated with episodic crevasse-opening events and longer-term, seasonally driven variations in crevasse activity linked to meltwater input.Spatial patterns of GNSS-derived velocities show strong tensile strain concentration at crevasse locations, which coincides with the spatial distribution of icequake activities recorded by a colocated array of 18 seismic geophones. We show not only hydrofracture-driven crevasse activities during melt seasons, but also that the presence of mega-crevasses modulates basal sliding velocity by promoting the transfer of surface meltwater to the glacier bed. Our results of field observations provide a foundation for future modeling of crevasse mechanics.
How to cite: Togaibekov, A., Khan, S. A., Løkkegaard, A., Colgan, W., and Pickell, D.: Temporal evolution and kinematics of a mega-crevasse at Jakobshavn Isbræ revealed by dense GNSS observations, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4680, https://doi.org/10.5194/egusphere-egu26-4680, 2026.
Marine-terminating glaciers in Arctic fjords exhibit complex and highly variable calving behavior, reflecting interactions between ice dynamics and fjord processes. Better understanding of calving is required for accurate prediction of ice loss, ocean freshening and sea level rise. Here, we study calving at seven marine-terminating glaciers in Hornsund Fjord, Svalbard over the period 2015 – 2022. To do so, we use combination of remote sensing products for glacier positions and dynamics, and measurements of other environmental parameters. We investigate the temporal variability of calving at seasonal and annual timescales, including the winter months which are usually not considered. Furthermore, we also study the spatial variability of calving along the glacier width, which further reveals small scale features on the termini related to different calving styles. Together, this work highlights the variable nature of calving across different glaciers within a single fjord.
How to cite: Maniktala, D. and Glowacki, O.: Glacier Calving in Hornsund Fjord, Svalbard: Spatio-Temporal Variability, Terminus Geometry, and Environmental Drivers, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11616, https://doi.org/10.5194/egusphere-egu26-11616, 2026.
Abrupt drainage of a proglacial lake provides an opportunity to investigate the response of a lake-terminating glacier to a water level change. In April–July 2020, Lago Greve, a large proglacial lake in the Southern Patagonia Icefield, abruptly drained and the lake level dropped by ~18 m. Using satellite remote sensing data from 2017–2021, we quantified changes in ice velocity, ice-front position, surface elevation, and frontal ablation of three lake-terminating glaciers (Glaciar Pío XI, Greve, and Lautaro), flowing into Lago Greve. The glaciers exhibited contrasting dynamic responses to the same magnitude of water level variation. Glaciar Pío XI decelerated to <10% of the pre-event speed during the drainage, most likely because of decrease in subglacial water pressure. Glaciar Greve showed speed-up, ice-front advance and surface lowering, which were triggered by the reduction in the hydrostatic water pressure acting on the glacier front. Glaciar Lautaro showed no clear response attributable to the drainage. These contrasting behaviors demonstrated the importance of individual settings, e.g., subglacial hydrology, bed geometry, and frontal ablation, to predict the dynamics of calving glaciers, including both lake- and marine-terminating glaciers.
How to cite: Hata, S. and Sugiyama, S.: Dynamic response of three lake-terminating glaciers to an abrupt drainage of Lago Greve, the Southern Patagonia Icefield, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6327, https://doi.org/10.5194/egusphere-egu26-6327, 2026.
Accurate estimation of frontal ablation of water‑terminating glaciers is essential for assessing global glacier mass change and projecting sea‑level rise. We present a hybrid framework that couples a SERMeQ‑based frontal‑ablation component with climatic mass‑balance from PyGEM and ice dynamics from OGGM, and we introduce an adaptive particle‑batch smoother to jointly calibrate all model parameters simultaneously. The model simulates centreline length change and mass‑balance components at monthly resolution and updates flow‑line geometry accordingly. Calibration assimilates both decadal averaged geodetic mass‑balance estimates and remote‑sensing annual timeseries terminus‑position changes, constraining the coupled dynamics and ablation processes within a single, physically consistent framework. Applied regionally to 71 tidewater glaciers in Svalbard, the framework reproduces observed seasonal behaviour and hindcasts, while providing improved projections of future glacier evolution. These results offer more robust regional estimates of contributions to sea‑level rise and freshwater availability and identify priorities for further reducing uncertainties in frontal‑ablation estimates.
How to cite: Yang, R., Ultee, L., Aalstad, K., Debolskiy, M., Hock, R., Schmitt, P., Rounce, D., and Li, T.: Modeling frontal ablation in global glacier models (Joint Bayesian), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12974, https://doi.org/10.5194/egusphere-egu26-12974, 2026.
