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Autonomous multi-robot missions are revolutionizing oceanographic data collection by increasing spatial coverage, mission durations, and allowing safe access to remote and dangerous environments at a fraction of the cost of ship-based missions. While terrestrial and aerial field robotics offer several approaches for multi-robot coordination, ocean applications present unique challenges — including navigation in a time-evolving, unknown, 3D fluid environment with significant drag, limited communications, and long-duration missions without opportunities to recharge — which require tailored solutions. To promote novel solutions arising from collaborations between field robotics and oceanography, we detail recent advances in terrestrial and aerial multi-robot coordination which we contextualize in relation to oceanographic needs, distinguishing applications at the ocean surface, at depth, and between the two domains. We conclude by highlighting future research opportunities, focusing on vehicle technology, underwater networking, and de-risking. We also emphasize that oceanographic and space missions share several similarities, making the ocean an excellent test bed for future developments. 

Multi-robot coordination under communication constraints is a fundamental challenge in autonomous systems, particularly in underwater environments, where low-bandwidth acoustic links restrict centralized planning and limit decentralized information propagation. In this study, we explore a “Mothership–passenger” paradigm, in which a capable underwater vehicle deploys and coordinates many lower-cost autonomous robots, enabling broad spatial coverage while reducing the mission risk and cost. We present two algorithms that tightly couple hierarchical guidance with decentralized planning to improve coordination efficiency under these constraints. The first algorithm integrates centralized and decentralized solutions to an underwater multi-robot orienteering problem, enabling globally coherent yet locally adaptive coordination among robots operating under stochastic travel costs and mission disruptions. The second algorithm introduces a learned policy on a Mothership vehicle that adaptively configures individual robot priorities, allowing globally informed guidance to shape local planning under communication and resource constraints. Through simulation and field experiments at an inland lake, we demonstrate that these contributions significantly improve coordination efficiency and robustness compared to fixed-behavior and fully decentralized baselines. These advances are directly motivated by the long-term goal of deploying coordinated robotic teams in isolated environments such as under-ice ocean regions, where the coordination and communication constraints studied here are most acute. 

Abstract. Bathymetry beneath ice shelves in West Antarctica plays an important role in the delivery and circulation of warm waters to the ice-shelf bottom and grounding line. Large-scale bathymetric estimates can only be inferred through inversion of airborne gravity measurements. However, previous bathymetry inversions have not robustly quantified uncertainty in the bathymetry due to assumptions inherent in the inversion, and typically only produce a single model, making it difficult to propagate uncertainty into ocean and ice-sheet models. Previous inversions have sometimes considered uncertainties in bathymetry models due to background densities but have not quantified the uncertainty due to the non-uniqueness inherent in gravity and geological variability below ice shelves. To address these issues, we develop a method to generate ensembles of bathymetry models beneath the Crosson, Dotson, and Thwaites Eastern ice shelves with independent realizations of background density and geological variability, represented through the Bouguer gravity disturbance. We sample the uncertainty in the unknown geology below the ice shelves by interpolating the Bouguer disturbance using Sequential Gaussian Simulation. Each inversion is efficiently computed using a random walk Metropolis Markov Chain Monte Carlo approach which randomly updates blocks of bathymetry and accepts or rejects updates. Our ensembles of bathymetry models differ from previous estimates of bathymetry by hundreds of meters in some areas and show that the uncertainty in the Bouguer disturbance is the largest source of uncertainty. The different bathymetry models in the ensembles can be used in oceanographic models to place better bounds on sub-ice-shelf melting and future grounding line retreat. 

Seismic travel time inversion code from: Geophysical evidence of tectonic structures beneath Thwaites Glacier, West Antarctica: influence on glacier dynamics. Submitted to Journal of Geophysical Research: Solid Earth 

Flexure modeling code for manuscript: Geophysical evidence of tectonic structures beneath Thwaites Glacier, West Antarctica: influence on glacier dynamics. Submitted to Journal of Geophysical Research: Solid Earth 

Results from seismic travel time inversion and potential fields modeling in: Geophysical evidence of tectonic structures beneath Thwaites Glacier, West Antarctica: influence on glacier dynamics 

Basal channels, which are troughs carved into the undersides of ice shelves by buoyant plumes of water, are modulators of ice-shelf basal melt and structural stability. In this study, we track the evolution of 12 large basal channels beneath ice shelves of the Amundsen and Bellingshausen seas region in West Antarctica using the Landsat record since its start in the 1970s through 2020. We observe examples of channel growth, interactions with ice-shelf features, and systematic changes in sinuosity that give insight into the life cycles of basal channels. We use the last two decades of the record, combined with contemporary ice-flow velocity datasets, to separate channel-path evolution into components related to advection by ice flow and those controlled by other forcings, such as ocean melt or surface accumulation. Our results show that ice-flow-independent lateral channel migration is overwhelmingly to the left when viewed down-flow, suggesting that it is dominated by Coriolis-influenced ocean melt. By applying a model of channel-path evolution dominantly controlled by ice flow and ocean melt, we show that the majority of channels surveyed exhibit non-steady behavior that serves as a novel proxy for increased ocean forcing in West Antarctica starting at least in the early 1970s. 

Knowledge gaps about how the ocean melts Antarctica’s ice shelves, borne from a lack of observations, lead to large uncertainties in sea level predictions. Using high-resolution maps of the underside of Dotson Ice Shelf, West Antarctica, we reveal the imprint that ice shelf basal melting leaves on the ice. Convection and intermittent warm water intrusions form widespread terraced features through slow melting in quiescent areas, while shear-driven turbulence rapidly melts smooth, eroded topographies in outflow areas, as well as enigmatic teardrop-shaped indentations that result from boundary-layer flow rotation. Full-thickness ice fractures, with bases modified by basal melting and convective processes, are observed throughout the area. This new wealth of processes, all active under a single ice shelf, must be considered to accurately predict future Antarctic ice shelf melt. 

Abstract Rift propagation, rather than basal melt, drives the destabilization and disintegration of the Thwaites Eastern Ice Shelf. Since 2016, rifts have episodically advanced throughout the central ice-shelf area, with rapid propagation events occurring during austral spring. The ice shelf's speed has increased by ~70% during this period, transitioning from a rate of 1.65 m d⁻¹in 2019 to 2.85 m d⁻¹by early 2023 in the central area. The increase in longitudinal strain rates near the grounding zone has led to full-thickness rifts and melange-filled gaps since 2020. A recent sea-ice break out has accelerated retreat at the western calving front, effectively separating the ice shelf from what remained of its northwestern pinning point. Meanwhile, a distributed set of phase-sensitive radar measurements indicates that the basal melting rate is generally small, likely due to a widespread robust ocean stratification beneath the ice–ocean interface that suppresses basal melt despite the presence of substantial oceanic heat at depth. These observations in combination with damage modeling show that, while ocean forcing is responsible for triggering the current West Antarctic ice retreat, the Thwaites Eastern Ice Shelf is experiencing dynamic feedbacks over decadal timescales that are driving ice-shelf disintegration, now independent of basal melt. 

Abstract Glacier-bed characteristics that are poorly known and modeled are important in projected sea-level rise from ice-sheet changes under strong warming, especially in the Thwaites Glacier drainage of West Antarctica. Ocean warming may induce ice-shelf thinning or loss, or thinning of ice in estuarine zones, reducing backstress on grounded ice. Models indicate that, in response, more-nearly-plastic beds favor faster ice loss by causing larger flow acceleration, but more-nearly-viscous beds favor localized near-coastal thinning that could speed grounding-zone retreat into interior basins where marine-ice-sheet instability or cliff instability could develop and cause very rapid ice loss. Interpretation of available data indicates that the bed is spatially mosaicked, with both viscous and plastic regions. Flow against bedrock topography removes plastic lubricating tills, exposing bedrock that is eroded on up-glacier sides of obstacles to form moats with exposed bedrock tails extending downglacier adjacent to lee-side soft-till bedforms. Flow against topography also generates high-ice-pressure zones that prevent inflow of lubricating water over distances that scale with the obstacle size. Extending existing observations to sufficiently large regions, and developing models assimilating such data at the appropriate scale, present large, important research challenges that must be met to reliably project future forced sea-level rise.