Stan Openshaw, P. Mather
Hasil untuk "Physical geography"
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Jeannine Wintzer
While most physical geographers have traditionally focused on natural processes, growing attention is now being paid to how people experience and respond to them. This shift reflects a broader recognition that the natural environment is not only material but also shaped by social, political, and cultural meanings. Accordingly, when people speak about nature, they tend to speak less about physical-geographical factors and more about emotional experiences. Natural hazards, for instance, are often perceived as recurring threats, deeply unsettling events, expressions of political neglect, or simply as part of everyday life. While these narratives are individual in form, they point beyond subjective feelings; they reflect social patterns of meaning and can be analysed as socio-spatial narratives such as inscriptions of (dis)trust or (dis)empowerment. To explore such meanings, qualitative inquiry complements quantitative approaches. However, in my daily work as a lecturer, supervisor, and as advisor in trans- and interdisciplinary research projects, I regularly encounter misconceptions about qualitative inquiry, especially among researchers with a natural science background. This paper clarifies the epistemological foundations, objectives, and potential outcomes of qualitative inquiry in physical geography to dispel common misconceptions. By doing so, I move beyond a narrow understanding of qualitative geography and instead highlight its capacity to critically engage with meaning-making processes, power relations, and situated knowledge in human–environment interactions. Thus, I encourage dialogue and mutual understanding between qualitative and quantitative researchers – particularly in the growing field of transdisciplinary and interdisciplinary research, where mixed-methods designs are increasingly prevalent.
Sergio Moreno, Mohamed Amine Doukani, Ana Hipólito et al.
During the last two decades, the Macaronesian archipelagos have been the focus of multiple studies targeting the abundant and diversified fossil record from late Neogene and Quaternary deposits. This record of past biota, ecosystems and climates is crucial for understanding the impact of glacial–interglacial cycles on Atlantic littoral marine organisms. Coupled with ongoing studies on the factors responsible for global climate change and associated sea-level variations, they contributed decisively towards the development of the modern marine island biogeography theory. Our current knowledge of the evolutionary and biogeographic history of the past and extant, shallow-water marine organisms from the Macaronesian geographic region relies on detailed analysis of many individual fossiliferous outcrops by means of quantitative and qualitative methodologies. Here, we focus on the fossil record of a newly studied MIS 5e outcrop at Pedra-que-pica (PQP), on Santa Maria Island (Azores Archipelago, Portugal). This multidisciplinary work integrates geology, paleontology and biology, providing the first detailed description of the sedimentary facies and stratigraphic framework of the PQP MIS 5e sequence that, coupled with the documentation of the biodiversity and ecological composition of PQP molluscan assemblages, allows us to produce a paleoecological reconstruction and to compare PQP with other last interglacial outcrops from Santa Maria Island. Our results increase the number of the Azorean MIS 5e marine molluscs to 140 taxa (116 Gastropoda and 24 Bivalvia). <i>Ervilia castanea</i> (Montagu, 1803) is the most abundant bivalve, while <i>Bittium nanum</i> (Mayer, 1864) and <i>Melarhaphe neritoides</i> (Linnaeus, 1758) are the most abundant gastropod species. In addition, this work emphasizes the crucial importance of complementing quantitative collecting with qualitative surveys of the fossiliferous outcrops, because nearly 42% of the bivalve species and 28% of the gastropod taxa would be missed if only quantitative samples were used. Derivation of Hill numbers and rarefaction curves both indicate that the sampling effort should be increased at PQP. Thus, although Santa Maria Island is recognized by the scientific community as one of the best-studied islands regarding the last interglacial fossil record, this study emphasizes the need to continue with similar efforts in less known outcrops on the island.
Seokhyun Chin, Junghwan Park, Woojin Cho
Precipitation nowcasting, key for early warning of disasters, currently relies on computationally expensive and restrictive methods that limit access to many countries. To overcome this challenge, we propose precipitation nowcasting using satellite imagery with physics constraints for improved accuracy and physical consistency. We use a novel physics-informed dual neural operator (PIANO) structure to enforce the fundamental equation of advection-diffusion during training to predict satellite imagery using a PINN loss. Then, we use a generative model to convert satellite images to radar images, which are used for precipitation nowcasting. Compared to baseline models, our proposed model shows a notable improvement in moderate (4mm/h) precipitation event prediction alongside short-term heavy (8mm/h) precipitation event prediction. It also demonstrates low seasonal variability in predictions, indicating robustness for generalization. This study suggests the potential of the PIANO and serves as a good baseline for physics-informed precipitation nowcasting.
Jiajia Guo, Yiming Cui, Shi Jin et al.
Large artificial intelligence models (LAMs) are transforming wireless physical layer technologies through their robust generalization, multitask processing, and multimodal capabilities. This article reviews recent advancements in applying LAMs to physical layer communications, addressing obstacles of conventional AI-based approaches. LAM-based solutions are classified into two strategies: leveraging pre-trained LAMs and developing native LAMs designed specifically for physical layer tasks. The motivations and key frameworks of these approaches are comprehensively examined through multiple use cases. Both strategies significantly improve performance and adaptability across diverse wireless scenarios. Future research directions, including efficient architectures, interpretability, standardized datasets, and collaboration between large and small models, are proposed to advance LAM-based physical layer solutions for next-generation communication systems.
Tianxin Xie, Wentao Lei, Guanjie Huang et al.
Text-to-audio-video (T2AV) generation underpins a wide range of applications demanding realistic audio-visual content, including virtual reality, world modeling, gaming, and filmmaking. However, existing T2AV models remain incapable of generating physically plausible sounds, primarily due to their limited understanding of physical principles. To situate current research progress, we present PhyAVBench, a challenging audio physics-sensitivity benchmark designed to systematically evaluate the audio physics grounding capabilities of existing T2AV models. PhyAVBench comprises 1,000 groups of paired text prompts with controlled physical variables that implicitly induce sound variations, enabling a fine-grained assessment of models' sensitivity to changes in underlying acoustic conditions. We term this evaluation paradigm the Audio-Physics Sensitivity Test (APST). Unlike prior benchmarks that primarily focus on audio-video synchronization, PhyAVBench explicitly evaluates models' understanding of the physical mechanisms underlying sound generation, covering 6 major audio physics dimensions, 4 daily scenarios (music, sound effects, speech, and their mix), and 50 fine-grained test points, ranging from fundamental aspects such as sound diffraction to more complex phenomena, e.g., Helmholtz resonance. Each test point consists of multiple groups of paired prompts, where each prompt is grounded by at least 20 newly recorded or collected real-world videos, thereby minimizing the risk of data leakage during model pre-training. Both prompts and videos are iteratively refined through rigorous human-involved error correction and quality control to ensure high quality. We argue that only models with a genuine grasp of audio-related physical principles can generate physically consistent audio-visual content. We hope PhyAVBench will stimulate future progress in this critical yet largely unexplored domain.
Yiqin Wang, Chong Han
The phenomenon that multi-path components (MPCs) arrive in clusters has been verified by channel measurements, and is widely adopted by cluster-based channel models. As a crucial intermediate processing step, MPC clustering bridges raw data in channel measurement and cluster characteristics for channel modeling. In this paper, a physical-interpretable and self-adaptive MPC clustering algorithm is proposed, which can locate both single-point and wide-spread scatterers without prior knowledge. Inspired by the concept in geography, a novel metaphor that interprets features of MPC attributes in the power-delay-angle profile (PDAP) as topographic concepts is developed. In light of the interpretation, the proposed algorithm disassembles the PDAP by constructing contour lines and identifying characteristic points that indicate the skeleton of MPC clusters, which are fitted by analytical models that associate MPCs with physical scatterer locations. Besides, a new clustering performance index, the power gradient consistency index, is proposed. Calculated as the weighted Spearman correlation coefficient between the power and the distance to the center, the index captures the intrinsic property of MPC clusters that the dominant high-power path is surrounded by lower-power paths. The performance of the proposed algorithm is analyzed and compared with the counterparts of conventional clustering algorithms based on the channel measurement conducted in an outdoor scenario. The proposed algorithm performs better in average Silhouette index and weighted Spearman correlation coefficient, and the average root mean square error (RMSE) of the estimated scatterer location is 0.1 m.
Katharina Simbeck, Mariam Mahran
Despite growing research on bias in large language models (LLMs), most work has focused on gender and race, with little attention to religious identity. This paper explores how religion is internally represented in LLMs and how it intersects with concepts of violence and geography. Using mechanistic interpretability and Sparse Autoencoders (SAEs) via the Neuronpedia API, we analyze latent feature activations across five models. We measure overlap between religion- and violence-related prompts and probe semantic patterns in activation contexts. While all five religions show comparable internal cohesion, Islam is more frequently linked to features associated with violent language. In contrast, geographic associations largely reflect real-world religious demographics, revealing how models embed both factual distributions and cultural stereotypes. These findings highlight the value of structural analysis in auditing not just outputs but also internal representations that shape model behavior.
Wenda Zhang, Christopher L. P. Wolfe
Abstract Mixing along isopycnals plays an important role in the transport and uptake of oceanic tracers. Isopycnal mixing is commonly quantified by a tracer diffusivity. Previous studies have estimated the tracer diffusivity using the rate of dispersion of surface drifters, subsurface floats, or numerical particles advected by satellite‐derived velocity fields. This study shows that the diffusivity can be more efficiently estimated from the dispersion of coherent mesoscale eddies. Coherent eddies are identified and tracked as the persistent sea surface height extrema in both a two‐layer quasigeostrophic (QG) model and an idealized primitive equation (PE) model. The Lagrangian diffusivity is estimated using the tracks of these coherent eddies and compared to the diagnosed Eulerian diffusivity. It is found that the meridional coherent eddy diffusivity approaches a stable value within about 20–40 days in both models. In the QG model, the coherent eddy diffusivity is a good approximation to the upper‐layer tracer diffusivity in a broad range of flow regimes, except for small values of bottom friction or planetary vorticity gradient, where the motions of same‐sign eddies are correlated over long distances. In the PE model, the tracer diffusivity has a complicated vertical structure and the coherent eddy diffusivity is correlated with the tracer diffusivity at the e‐folding depth of the energy‐containing eddies where the intrinsic speed of the coherent eddies matches the rms eddy velocity. These results suggest that the oceanic tracer diffusivity at depth can be estimated from the movements of coherent mesoscale eddies, which are routinely tracked from satellite observations.
Thayná Alice Brito Almeida, Abelardo Antônio de Assunção Montenegro, Rae Mackay et al.
Study region: Mimoso Alluvial Valley, Semiarid Brazil. Study focus: This study aims to assess the influence of climate variability and exploitation on groundwater accessibility, quantity and quality, based on a spatiotemporal data analysis from long-term monitoring field campaigns, conducted monthly from 2000 to 2019. This study successfully identified representative stable monitoring points, piezometers and wells, for piezometric and salinity levels employing the technique of relative differences, taking into account aquifer hydraulic properties. Trend analysis was then carried out adopting the Mann-Kendall Method, Sen's Slope test, Pettitt test, and the Seasonal Trend decomposition through the Loess (STL) method. Principal Component Multivariate Analysis (PCA) was also employed to validate long-term analysis of annual groundwater levels, rainfall, evapotranspiration, and pumping rates. New hydrological insights for the region: The spatial-temporal variability of salinity is closely linked to the salt balance in regions with low hydraulic permeability and groundwater use for irrigation. Groundwater salinity presented a strong link between rainfall and groundwater levels. A temporal rise in evapotranspiration alongside declines in rainfall and groundwater levels was observed, potentially exacerbating groundwater scarcity alongside intensified aquifer exploitation. Furthermore, groundwater salinity presented a decreasing trend for the pumping wells and no trends for piezometers. This could potentially disrupt future irrigation plans and cause long-term water shortages in a region already under severe water scarcity. Hence, groundwater pumping constitutes a positive management alternative for controlling groundwater salinity in the domain.
Saeid Maleki, Seyed Hossein Mohajeri, Amir Samadi et al.
Study Region: The Hirmand River Basin is a vital transboundary river system, that originates in Afghanistan’s Hindu Kush Mountains and flows into the Sistan Depression, and encompassing the Chah Nimeh Reservoirs in Iran and the Godzareh Depression in Afghanistan. Study Focus: The Kamal Khan Dam, constructed on the Hirmand River in Afghanistan, has significantly altered the downstream water direction and distribution between the Chah Nimeh Reservoirs and Godzareh Depression. Utilizing remote sensing techniques, particularly Landsat 8 satellite imagery and the FAO 56 PM as a evaporation retrieval method, the research focuses on evaluating changes in water allocation and evaporation rates in these regions over the past decade. New Hydrological Insights for the Region: The findings reveal that after operation of the Kamal Khan Dam, water allocation to the Chah Nimeh Reservoirs has drastically decreased, leading to a 54 % reduction in their average area from 2020–2023 compared to the previous years. Conversely, the Godzareh Depression, now receiving the redirected water, has experienced significantly higher evaporation rates, contributing to substantial water losses. These changes underscore the critical need for effective water management strategies to address the escalating water scarcity and hydrological imbalances in this arid region.
Azar Beyranvand, Ghasem Azizi, Omid Alizadeh et al.
Abstract We detected sources of dust in the Middle East that contribute to dust events in Western Iran in different seasons. By the analysis of the synoptic data, we identified 309 dusty days in Western Iran during the period 2000–2016. A dusty day is diagnosed if under low horizontal visibility (< 1 km), the dust in suspension is reported at least once a day in at least three synoptic stations. We identified dust sources in the Middle East based on the analysis of the MOD04L2 data from MODIS, the backward HYSPLIT trajectory model, and synoptic conditions. The most influential sources affecting Western Iran are located on the shore and northwest of Lake Tharthar, Hour-al-Azim Marsh, the shore of Razzaza, Habbaniyah Lakes, and West Hammar Marsh, which contributed to 110, 79, 59, 56, and 51 dusty days, respectively. The fluctuation of the surface water area largely contributes to the variability of dusty days in Western Iran. Indeed, the peak dust activity in Western Iran was during the period 2008–2012 in response to the substantial shrinkage of the main water bodies in Iraq. The main sources of dust influencing Western Iran are located in northern and eastern Saudi Arabia in spring, Deir ez-Zur in Syria’s Aleppo and Raqqa in summer, and Syria’s Homs and Al-Hasakah in winter and spring. Sources of dust in Western Iraq and in most parts of entire Iraq have, respectively, led to the formation of summer and spring dust events in Western Iran. Decreased precipitation in the Middle East from autumn 2007 to 2012 and the occurrence of severe droughts have also contributed to the shrinkage of lakes and wetlands, as well as the reduced agricultural productivity in the Middle East, all of which contributed to the intensification of dust activity in Western Iran in recent decades.
Natalia Albuquerque, Carine Savalli, Marina Belli et al.
Capuchin monkeys have rich social relationships and from very young ages they participate in complex interactions with members of their group. Lipsmacking behaviour, which involves at least two individuals in socially mediated interactions, may tell about processes that maintain, accentuate or attenuate emotional exchanges in monkeys. Lipsmacking is a facial expression associated with the establishment and maintenance of affiliative interactions, following under the ‘emotional regulation’ umbrella, which accounts for the ability to manage behavioural responses. We investigated behaviours related to the emitter and to the receiver (infant) of lipsmacking to answer the question of how lipsmacking occurs. In capuchin monkeys, lipsmacking has been previously understood solely as a face-to-face interaction. Our data show that emitters are engaged with infants, looking longer towards their face and seeking eye contact during the display. However, receivers spend most of the time looking away from the emitter and stay in no contact for nearly half of the time. From naturalistic observations of wild infant capuchin monkeys from Brazil we found that lipsmacking is not restricted to mutual gaze, meaning there are other mechanisms in place than previously known. Our results open paths to new insights about the evolution of socio-emotional displays in primates.
Sally Ghannam, Edward P. Levri
The aquatic, invasive New Zealand mud snail (Potamopyrgus antipodarum) exploits a variety of food sources. Here we examine the change in growth of snails that fed on periphyton colonizing leaf litter, wood, rock, and a control. Juveniles were grown in the lab on Spirulina algae powder (control) or periphyton grown on rock, leaf litter, or wood. Length was measured at the beginning of the experiment and after eight weeks. Snails grown on leaf litter increased in length more than twice as much as the control and the snails in the rock treatment, and the snails grown on wood showed an increase in length more than twice as much as snails in the rock treatment. This suggests that allochthonous material may contribute to a more nutritious food source for New Zealand mud snails and possibly aid in their invasion success.
Alessandro Pinto
Several sources of uncertainty have to be taken into account in the analysis and design of CPS. The set of parameters used in the model of the physical plant of a CPS may be uncertain due, for example, to manufacturing processes that are precise up to some bounded tolerance. Physical quantities are sensed by electronic components that add noise to the sensed signals. Abstraction of the physical world, which is often necessary to limit the complexity of the models used in analysis and at run-time in decision-making, leads to non-determinism. The cyber side of a CPS, which includes both hardware and software components, exposes several types of uncertainty such as failures, latency, and implementation errors. Design processes and tools allow engineers to minimize the impact of these types of uncertainty, and to deliver systems which can be operated with an acceptable level of risk. In the past several years, cyber-physical systems have evolved, primarily due to pervasive connectivity, miniaturization, cost-effectiveness of hardware, and advances in the area of Artificial Intelligence. This new class of applications features an environment that is much more complex to model than traditional physical systems due not only to their scale, but also to new sources and types of uncertainty. Consider, for example, the typical case of echo chambers which is attributed to the effect that machine learning algorithms have on the bias of people. Such behavior is not easily predictable because of high uncertainty in the environment (people), which is only approximately represented by machine learning models, but that is inherently due to lack of knowledge. New models and analysis methods are therefore needed to capture different types of uncertainties, and to analyze these new classes of systems.
David Dunkerley
Sound is produced by many geomorphic and hydrological processes, such as rockfalls and landslides, ocean waves, fluvial flood flows and collisions among moving bedload clasts. In these and other areas of study, acoustic methods have found useful application to detect and quantify the operation of important landscape processes. In some, such as the recording of river discharge, the occurrence of rare events such as exfoliation or the presence and movement of dust devils (willy-willies), the use of acoustic methods is still in a relatively early stage of development and testing. The use of acoustic methods in the recording of rainfall occurrence and intensity is also developing and has the capacity to yield data with higher temporal resolution than can be achieved using conventional rain gauges. Novel acoustic methods include the analysis of the sound recorded by security cameras, which potentially form a vast network of observing stations. The frequencies of sound generated by land-surface processes include audible sound, ultrasound and infrasound at frequencies below the human hearing range. All appear to provide opportunities for further development of useful research tools and methodologies.
Robert Anders, Matthew K. Landon, Peter B. McMahon et al.
Study region: Santa Barbara County, California, USA. Study focus: To analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area. New hydrological insights for the region: Three of 15 groundwater samples had compositions indicating potential mixing with water and/or thermogenic gas from oil-bearing formations. Relevant indicators included salinity tracers (TDS, Cl, Br), NH3, DOC, enriched δ13C-DIC, δ2H-CH4, δ13C-CH4, and δ13C-C2H6 values, and trace amounts of C3-C5 gas. The potential sources/pathways for oil-bearing formation water and/or thermogenic gas in groundwater overlying and adjacent to the Orcutt Oil Field include: (1) upward movement from formations developed for oil production due to: (a) natural migration; or (b) anthropogenic activity such as injection and/or movement along wellbores; and (2) oil and gas shows in overlying non-producing oil-bearing formations. Groundwater age tracers, elevated 4He concentrations, and isotopic compositions of noble gases indicated legacy produced water ponds were not a source. This phase of the study relied on samples and data from existing infrastructure. Additional data on potential end-member compositions from new and existing wells and assessments of potential vertical head gradients and pathways between oil and groundwater zones may yield additional insight.
Xiaoyan Gong, Baisha Weng, Denghua Yan et al.
Study region: The Nagqu River Basin in the central part of the Qinghai–Tibet Plateau, China. Study focus: Groundwater flow systems in permafrost regions are characterized by a unique circulation. Understanding the groundwater circulation mechanism is essential for studying the hydrological effect of permafrost degradation in alpine regions. In this study, potential water sources and origin of solutes in the groundwater of a typical alpine region were studied using hydrochemistry, 18O, 2H and 3H analyses. This research is essential for studying the hydrological effects of permafrost degradation. New hydrological insights for the region: Upon moving from the mountainous region to the plains, the renewal rate decreases from 10.5% to 0.6% and the mean transit time increases from 5–30 to 20–32 years. Groundwater is mainly recharged by ground ice meltwater and infiltration of glacier meltwater, snow meltwater and precipitation in mountainous areas, and by deep groundwater near faults. Discharge to surface water, evaporation, and overflow into springs are the main drainage modes. Water/ice–rock/soil interactions, such as dissolution of aluminosilicate minerals, are the main factors affecting the hydrochemical evolution. This study provides a data-driven approach for understanding groundwater recharge and evolution in similar systems.
C. Willmott
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