Bracken fern (Pteridium aquilinum (L.) Kuhn) is an invasive species with significant ecological and economic impacts, making its detection and mapping critical for effective management. This study reviews remote sensing techniques for mapping P. aquilinum from 1996 to 2023. A total of 32 peer-reviewed articles were selected from Web of Science (WOS) and Scopus following the screening of 1,612 retrieved records. Bibliometric analysis, using VOSviewer software and Social Network Analysis (SNA), explored Keyword relationships, author collaborations, and institutional contributions. The research output shows fluctuations, publication gaps, and a resurgence in interest post 2021. Most studies (28%) were conducted in North America and Europe, with 26% originating from Africa. Key sensors identified include Landsat, Worldview-2, SPOT-5, and Unmanned Aerial Vehicles (UAVs). Recent advancements demonstrated the effectiveness of high-resolution optical sensors and machine-learning models in improving detection accuracy. However, challenges remain, including data limitations, methodological inconsistencies, and classification accuracy issues. This review emphasizes the need for higher-resolution imagery, advanced machine learning approaches, and standardized methodologies for improved P. aquilinum monitoring. Enhanced detection methods are crucial for effective ecological management, early intervention, and mitigating the spread of P. aquilinum.

Glacial lakes are increasing in number and size worldwide, posing growing risks for outburst floods. Norway’s last glacial lake inventory used semi-automatic mapping on Sentinel-2 imagery from 2018–19. In this study, we test a more automated and reproducible workflow for updating glacial lake extents in Norway using Sentinel-2 and Sentinel-1 satellite imagery and a Random Forest classifier. Here, glacial lakes are defined as water bodies within 200 m of glaciers larger than 0.1 km2 with a minimum lake size of 400 m2. A 10th-percentile Sentinel-2 summer composite from 2023–24 mitigated snow and cloud cover, while Sentinel-1 ascending-descending difference composites reduced shadow misclassification without relying on DEMs. Validation across six glacier regions shows high detection reliability (F1-score: 0.81) as well as high delineation accuracy (median deviation <6.5 m). However, manual correction remains necessary, especially in steep terrain. We identified 1382 glacial lakes in 2023–24, covering 124 km2—a substantial increase relative to 2018–19. Excluding regulated lakes and adjusting for methodological differences, we estimate a 9–22% lake area increase over the past five years, mainly driven by glacier retreat. The workflow is efficient and reproducible, but regional threshold adaptation and retraining are required for transfer to other regions.

An alpine glacier below Sunlight Peak in northwest Wyoming was first photographically documented in 1893, near the end of the Little Ice Age and during the time of industrialization. Since then, evolving technologies have been applied to observe this glacier and nearby discontinuous permafrost for studies spanning Earth, environmental, and planetary sciences. Surveys in the 21st century indicate negative mass balance coinciding with rising average air temperature. This paper reviews the geological and geophysical data on record for the Sunlight Glacier system, presents new results from a 2023 fieldwork campaign combined with remote sensing analysis and comments on likely scenarios of future evolution for this individual body of ice within a broader alpine cryosphere feeding the watersheds of western North America.

Analysis of historic aerial photography has identified a possible monumental formal garden complex on the outskirts of Tabriz, Iran. Here, the authors describe this complex and explain why it is an important addition to our knowledge of elite Persian garden design practice that spread globally over time.

Monitoring snow distribution in alpine terrain is critical for hydrology, avalanche safety, and climate research, yet traditional surveys are costly, hazardous, and spatially sparse. We assess a gondola-mounted, low-cost Light Detection and Ranging (lidar) system (MOLISENS) for repeated snow monitoring in Real-Time Kinematics (RTK)-denied mountain environments. The system fuses lidar, Inertial Measurement Unit (IMU), and standalone Global Navigation Satellite System (GNSS) using a Simultaneous Localization And Mapping (SLAM) algorithm to generate 3D point clouds along a fixed aerial-lift transect at Hoher Sonnblick, Austria. Six winter runs (March 2023) were processed and compared with summer Unmanned Aircraft System (UAS)-photogrammetry. Intra-system repeatability between same-day scans reached centimetre precision (weighted standard deviation 0.010 m; 95% within $\pm$0.006 m), supporting detection of daily to seasonal changes in snow thickness along the route. Absolute agreement with the UAS reference was limited to decimetre scale, primarily due to registration and standalone GNSS uncertainties rather than sensor range noise. Performance degraded over feature-poor snowfields, and manual segment merging was labor-intensive; consequently, quantitative analyses were restricted to well-constrained segments. Despite these limitations, the results demonstrate the feasibility of gondola-mounted lidar for cost-effective, repeatable snow-thickness mapping.

Strain rate and stress are widely regarded as crucial indicators for quantifying glacier dynamics on sub-monthly scales. However, existing frameworks for quality assessment of both strain rate and stress in fast-moving glaciers remain insufficient, hindering the application of rheological analysis to complex dynamic natural processes. To address this gap, we first extract and evaluate the surface velocity fields and their gradients from Sentinel-2A/B imagery using the Normalised Cross-Correlation (NCC) approach for Helheim Glacier, eastern Greenland. The results indicate that the minimum time threshold significantly affecting velocity gradients is 10 days for the Sentinel-2A/B missions, and that the threshold varies with season. We further develop a method based on error theory to enhance the retrieval accuracy of strain rate and stress at sub-monthly baselines, thereby supporting high-resolution dynamic research on Helheim Glacier. Our evaluations demonstrate the applicability of the NCC method to sub-monthly time scales and rapidly changing regions, thereby contributing to the quantification of glacier changes in a warming world.

Emperor penguins are highly reliant on stable fast ice for successful breeding, and some studies project possible quasi-extinction for most colonies by 2100 due to future sea-ice loss. To better understand the future response of emperor penguins to ocean-climate warming and the possibility of major changes to their habitat, it is essential to better understand how colonies have responded to past changes in ice conditions. In this study, we identify the historical locations of the SANAE, Astrid and Mertz colonies in all available Landsat 4–9, Advanced Spaceborne Thermal Emission and Reflections satellite (ASTER) and Sentinel-2 imagery for the period 1984–2024. We record the location and surface type of the colonies’ breeding locations each year while also recording major calving events, early fast-ice breakouts, distance to the fast-ice edge, and colony location span within a season. The results show that colonies usually return to approximately the same sites annually, but we observe variations due to major calving events. Following such events at Mertz (2010) and SANAE (2011), colonies relocate to different sites, where they may be more vulnerable to early fast-ice breakout or must travel longer distances to the fast-ice edge. In subsequent years, the colonies eventually return to sites close to their original location. Additionally, we observe early fast-ice breakouts that may impact breeding success at Mertz and SANAE colonies, including as early as September at Mertz (2016). Such breakouts coincide with both broader sea-ice lows and variations in colony location. Furthermore, all three colonies move onto the adjacent ice shelf in some years (and at Astrid and Mertz, also icebergs), including when stable fast ice is available, suggesting that this behaviour may be more common than previously thought. Observation of these behaviours contributes to broader understanding of emperor penguins’ adaptability and will aid future efforts to model the response of the species to ice loss.

Melting alpine ice threatens (pre)historic archaeological sites. Current trends suggest loss of ice will continue. Here, we present recent fluctuations in yearly minimum extent from 2017 to 2024 for three central Norwegian ice patches: Storhornet, Elghøa and Lågtangan. We discuss how melting ice affects their archaeological potential and introduce the term ghost patch to describe archaeological ice patch sites no longer containing ice. Future archaeological fieldwork prioritization must account for ice patch to ghost patch transitions. We suggest updated archaeological approaches for a future with less and less ice.

Glacial lakes in the Kashmir Himalaya have remained understudied despite their destructive potential for outburst floods. This study presents a comprehensive, manually delineated glacial lake inventory of 155 glacial lakes and a baseline for glacial lake outburst flood (GLOF) hazard across the region. Lakes are characterized by type and assessed for long-term spatio-temporal dynamics using a multi-temporal Landsat series in a GIS environment from 1992 to 2024. The area of ice-contact proglacial lakes increased by 26% during the 32-year observation period. A multi-criteria analysis-based framework validated by historical GLOFs in the Himalayan region is employed to evaluate the lake outburst susceptibility. Key factors such as dam material, slope gradient, upstream cascades, seismic activity and permafrost occurrence, are integrated in the susceptibility framework. Potential outburst events from five lakes categorised as having very high GLOF susceptibility threaten several thousand buildings, 15 major bridges, roads and a hydroelectric power project. The study also highlights the potential for GLOF process chains in the region, where upstream lake outbursts could trigger secondary events downstream. The five most susceptible lakes identified here may require intensive monitoring and risk management initiatives to protect vulnerable downstream communities and infrastructure.

This conversation began as a roundtable at the 2023 joint meeting of the American Anthropological Association and the Canadian Anthropology Society in Toronto. The roundtable was part of the Executive Program and was intended as a follow-up to Kisha Supernant’s keynote presentation, which was entitled ‘Truth before transition. Reimagining anthropology as restorative justice.’ Considering the sensitive nature of the topic, we responded to a selection of written questions from the audience rather than taking open questions. The discussion was webcast, then transcribed and redacted. This article includes a portion of the question period as well as a contextual introduction that was not part of the initial conversation.

Aerial lidar (light detection and ranging) has been hailed as a revolutionary technology in archaeological survey because it can map vast areas with high-precision and seemingly peer beneath forest cover. This excitement has led to a proliferation of lidar scans, including calls to map the entire land surface of earth. Highlighting how the growth of aerial lidar is tied to fast capitalism, this article seeks to temporarily pause the global rush for data collection/extraction by focusing on the ethical dilemmas of remotely scanning Indigenous homelands and heritage. Although lidar specialists must obtain federal permissions for their work, few engage with people directly in the path of their scans or descendant stakeholders. This oversight perpetuates colonial oppression by objectifying Indigenous descendants. To address Indigenous objectification, I argue that aerial lidar mapping should be preceded by a concerted, culturally sensitive effort to obtain informed consent from local and descendant groups. With the Mensabak Archaeological Project as a case study, I demonstrate how aerial lidar can become part of a collaborative, humanizing praxis.

Continued deglaciation in the Bolivian Andes threatens regional water security and may result in increased exposure to geohazards. We analyse high spatial resolution (∼3–5 m) satellite imagery to constrain annual glacier and glacial lake evolution across the Bolivian Andes between 2016 and 2022. The total glaciated area of the region decreased by 9.1%, from 316.6 ± 3.2 km2 to 287.8 ± 2.9 km2; a rate of loss of 4.8 km2 a−1. Concurrently, the number (total surface area) of glacial lakes increased by 2.6% (1.9%), from 704 (37.1 ± 0.7 km2) to 770 (37.8 ± 0.8 km2). A comprehensive glacial lake outburst flood susceptibility analysis was undertaken for the 2022 lake inventory, with eleven lakes identified as ‘high susceptibility’. Subglacial topographic analysis was undertaken to predict potential future sites for lake formation. We identified 55 such sites given continued deglaciation. The model was tested by applying it to areas where glaciers retreated between 2000 and 2022. Of the 22 potentially susceptible lakes which formed during this period, 14 (64%) did so in overdeepenings identified by the model. This is the first time that an inventory of potential future lake sites has been produced for the region.

This study presents the design and analysis of a dual linear polarized sinuous antenna (DLPSA) optimized for ultra-wideband applications, such as remote sensing of longitudinal metallic targets and microwave imaging systems. The capability of the sinuous antenna to generate dual linearly polarized radiation patterns makes it a strong candidate for these applications. A key design challenge lies in developing a practical feeding network that requires modifications to the antenna feed region. The proposed DLPSA antenna achieves unidirectional radiation patterns in the 2–5 GHz frequency band. A prototype was fabricated, with measured results closely aligned with the simulations. The antenna demonstrates enhanced return loss, gain, and radiation pattern performance compared to existing designs. Additionally, the dual linear polarization capability was verified through co- and cross-polarization measurements conducted in an anechoic chamber.

Tropical Andean glaciers provide an important flux of freshwater to communities living both in high-altitude Cordillera and population centres downstream in countries such as Peru and Bolivia. Glacier recession threatens the sustainability of these water resources, and accurate modelling of future glacier behaviour is required to manage water stress in the region. These models must capture all processes contributing significantly to overall glacier mass budgets. Here we examine supraglacial pond and ice cliff development on three clean-ice glaciers in the Cordillera Vilcanota, Peru and their overall contribution to glacier mass balance. Whilst such features are common and well-studied on debris-covered glaciers, their development on debris-free glaciers has not been examined in detail. We use high-resolution contemporary and historical satellite imagery and repeat drone surveys to examine surface structure and geometry change over three glaciers during 1977–2024. We show how cliff and pond formation is driven by aspect-dependent surface melt of crevasse walls. These features act as ice loss hotspots, which enhance glacier net mass loss by ∼10% despite accounting for <5% glacier surface area. Incorporation of such amplified ice loss processes should be a priority for glacier model advances to achieve more accurate projections of future tropical glacier recession.

For pedestrian archaeological surveys in agricultural regions, field plowing and crop cultivation are essential mechanisms for bringing artifacts to the surface and making them visible. Although agricultural land use can affect plowzone assemblages, few studies have tested the relationship between how frequently agricultural land is cultivated and the quantity of artifacts recovered. Such an evaluation would require a multiyear record of land use across extensive survey areas, thereby presenting numerous obstacles and challenges. Yet the ever-expanding availability of high temporal and spatial resolution satellite imagery datasets, combined with the accessibility of new tools for analyzing such datasets, makes studies of land-use intensity increasingly feasible. To demonstrate, we present our remote sensing–based evaluation of land-use intensity within the Province of Oristano (west-central Sardinia, Italy), where the Sinis Archaeological Project (SAP) has worked since 2018. Drawing on Sentinel-2 satellite imagery from the past six years, we investigate what factors may explain the modern-day distribution of land-use intensities, which areas SAP has targeted, and what effect land-use intensity has on artifact distribution. We find that modern-day land-use intensity is largely a legacy of recent land reclamation efforts and find no correlation between the intensity of surveyed fields and the quantity of materials recovered therein.

Following the identification of more than 600 suspected house platforms on aerial survey data from Brusselstown Ring hillfort, four test excavations revealed evidence of Late Bronze Age and Early Iron Age occupation, positioning the site as the largest nucleated settlement so far identified in prehistoric Ireland and Britain.

The Lunana region in Bhutan, which hosts four large glacial lakes with significant hazard potential, has undergone rapid changes over the past decade. Using PlanetScope satellite scenes, we mapped ice velocities at monthly intervals from 2017 to 2023. We reveal that the disintegration of Thorthormi Glacier’s terminus in 2022 coincided with year-on-year acceleration with mean surface velocities as high as 448 ± 10.0 m a−1 by 2021, and seasonal variability in surface velocity magnitude >144.6 ± 10.0 m a−1. This acceleration is attributed to a reduction in basal drag as the terminus reached flotation, evidenced by the calving of tabular icebergs. While Bechung, Raphstreng and Lugge exhibited a similar interannual velocity trend, the upper regions of Bechung and Raphstreng showed a higher seasonal range (31% and 19.9% from their mean) compared to Lugge (4.2%). In the upper regions, we also find a decelerating velocity trend (3.5–20.6% over the 6 years), which is attributed to surface thinning and reducing driving stresses. We show that accelerating trends in velocity can be a precursor to higher rates of retreat and rapid lake expansion, demonstrating the importance of continuous monitoring of lake-terminating glacier ice velocities in the Himalaya.

Glaciers provide critical ecosystem services, including water resources, biodiversity, cultural value and climate signals. But what makes a glacier a glacier? And when is a glacier no longer a glacier? Different glacier definitions can conflict. While a common definition emphasizes ‘past or present flow’, practical applications involve criteria like observable ice flow, crevassing, minimum thickness, minimum area, surficial features related to hydrology and/or debris cover and/or relative size. Increasingly, glacier inventories apply multiple criteria, acknowledging the nuanced, continuous nature of glacier retreat rather than a binary status. In the context of increasingly melting, shrinking and vanishing glaciers, as glaciologists consider when to declare a glacier lost, disappeared or dead, it is important to explore glacier definitions and their application. Ultimately, the glacier definition applied depends on the specific context, purpose and audience. This also highlights the need for careful language choice, clear communication and localized expertise in considering glacier loss.

Tropical cyclones (TC) can produce waves and water levels that markedly reshape sand cay shorelines. TC Jasper (December 2023) passed near Low Island (Low Isles, Northern Great Barrier Reef [GBF]) as a category 2 storm. Using a combination of remote sensing and ground surveys, we compare detailed, high-resolution digital terrain models created before and after TC Jasper to quantify sediment redistribution around the cay during and after the event. During TC Jasper, net transport of 8,870 m3 occurred to elongate the spits at the eastern and western ends of the cay, but the sediment volume of the cay did not significantly change. Following TC Jasper, the shoreline at Low Island returned to its modal seasonal state within six months. This accords with historical accounts of seasonal shifts in shoreline configuration driven by prevailing wind and wave regimes, as well as the relatively rapid readjustment to a modal form following episodic extreme events. Overall, the documented changes to Low Island following cyclonic events highlight the complex interplay between episodic disturbances and longer-term geomorphic stability, emphasising the importance of ongoing research into these interactions as higher-intensity cyclones increase in frequency due to climate change.

Groundwater is a critical support system for agriculture, domestic and industrial consumption in India, but escalating depletion and climatic stresses underscore the need for scientifically robust groundwater potential zone (GWPZ) mapping. In response to the aggravating water security issues in India, this study presents a critical and systematic-methodical review of research articles focused on GWPZ mapping. The primary goal of this research is to integrate input parameters, modeling techniques and validation methods to produce an evidence-based framework for selecting appropriate and effective GWPZ mapping strategies. Six prominent thematic categories – topography, geology, hydrology, climate, land cover and aquifer properties – seem to be inevitably predominant in different physiographic zones. Methodological tendencies suggest a shift from conventional Multi-Criteria Decision-Making models, that is, Analytical Hierarchy Process and Frequency Ratio, toward sophisticated machine learning techniques like Random Forests, Support Vector Machine and Extreme Gradient Boosting. Validation practices are dominated by a high incidence of receiver operating characteristic curve analysis and area under the curve metrics, with occasional addition of precision, recall, F1-score and root mean square error. Across the studies reviewed, field-derived data, well yield, groundwater depth, aquifer thickness and resistivity surveys remain critical for ground-truthing model results. Our view is that even though Indian GWPZ research has taken significant methodological strides, regional data heterogeneity, aquifer complexity and climatic variability issues continue to pose a key challenge in GWPZ mapping. We suggest future strategies involving high-resolution datasets, three-dimensional subsurface modeling, climate-resilient algorithms and more diversified validation frameworks. Through this critical synthesis, the article presents an integrated guide to support planners select cost-effective mapping techniques, inform policymakers on strategic investments and data collection priorities and direct researchers toward the most critical scientific gaps in India’s increasingly dynamic hydro-environmental context.