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Geothermal heat plays a vital role in Antarctic ice sheet stability. The continental geothermal heat flow distribution depends on lithospheric composition and ongoing tectonism. Heat‐producing elements are unevenly enriched in the crust over deep time by various geological processes. The contribution of crustal heat production to geothermal heat flow is widely recognized; however, in Antarctica, crustal geology is largely hidden, and its complexity has frequently been excluded in thermal studies due to limited observations and oversimplified assumptions. Li and Aitken (2024), https://doi.org/10.1029/2023GL106201 take a significant step forward, focusing on Antarctic crustal radiogenic heat. Utilizing gravity inversion and rock composition data, they show that the crustal heterogeneity introduces considerable variability to heat flow. However, modeling crustal heat production proves challenging because it lacks distinct associations with geophysical observables and has a narrow spatial association. Robust quantification of geothermal heat production and heat flow must incorporate explicit aspects of geology. Plain Language Summary Even moderate amounts of geothermal heat, or the natural warmth from the Earth's interior, can cause the base of Antarctica's ice sheets to melt or change how the ice behaves as it flows slowly toward the coast. Geothermal heat is not evenly spread within continents. Instead, it's influenced by how plate tectonics has affected the types of rocks present. While scientists agree that the Earth's crust is a major contributor to geothermal heat generation, studies in Antarctica have often left out how rock type differences might affect heat distribution. The study by Li and Aitken (2024), https://doi.org/10.1029/2023gl106201 looks more closely at how the Earth's crust beneath Antarctica varies and how that affects the heat impacting its ice sheets from below. In this commentary, we highlight that although heat production is difficult to model, their findings are important for understanding the natural influences on ice sheets as we observe and predict the impact of ongoing climate change. However, to provide robust estimates, a detailed geological understanding is required. Key Points Antarctic ice sheet stability is highly dependent on the crustal contribution of radiogenic heat production to geothermal heat flow Contrasts in crustal density may indicate upper crustal radiogenic heat production distributions Robust geothermal models need to factor in heterogeneity at the scales of intrusions, metamorphic facies, and sedimentary units

A MCOHP (micro-channel oscillating heat pipe) can provide lightweight and efficient temperature control capabilities for aerospace spacecraft with a high power and small size. The research about the heat flow effects on the thermal performance of MCOHPs is both necessary and essential for aerospace heat dissipation. In this paper, the heat flow effects on the thermal performance of MCOHPs are summarized and studied. The flow thermal performance enhancement changes of MCOHPs are given, which are caused by the heat flow work fluids of nano-fluids, gases, single liquids, mixed liquids, surfactants, and self-humidifying fluids. The use of graphene nano-fluids as the heat flow work medium can reduce the thermal resistance by 83.6%, which can enhance the maximum thermal conductivity by 105%. The influences of gravity and flow characteristics are also discussed. The heat flow pattern changes with the work stage, which affects the flow mode and the heat and mass transfer efficiency of OHP. The effective thermal conductivity varies from 4.8 kW/(m·K) to 70 kW/(m·K) when different gases are selected as the working fluid in OHP. The study of heat flow effects on the thermal performance of MCOHPs is conducive to exploring in-depth aerospace applications.

Antarctic geothermal heat flow (GHF) affects the temperature of the ice sheet, determining its ability to slide and internally deform, as well as the behaviour of the continental crust. However, GHF remains poorly constrained, with few and sparse local, borehole-derived estimates and large discrepancies in the magnitude and distribution of existing continent-scale estimates from geophysical models. We review the methods to estimate GHF, discussing the strengths and limitations of each approach; compile borehole and probe-derived estimates from measured temperature profiles; and recommend the following future directions. (1) Obtain more borehole-derived estimates from the subglacial bedrock and englacial temperature profiles. (2) Estimate GHF from inverse glaciological modelling, constrained by evidence for basal melting and englacial temperatures (e.g. using microwave emissivity). (3) Revise geophysically derived GHF estimates using a combination of Curie depth, seismic, and thermal isostasy models. (4) Integrate in these geophysical approaches a more accurate model of the structure and distribution of heat production elements within the crust and considering heterogeneities in the underlying mantle. (5) Continue international interdisciplinary communication and data access.

From a subsurface physical point of view, this paper discusses the necessity of considering the two‐phase heat and mass transfer process in land surface models (LSMs). The potential‐based equations of coupled mass and heat transport under constant air pressure form the basis of the proposed model. The model is developed considering dry air as a single phase, and including mechanical dispersion in the water vapor and dry air transfer. The adsorbed liquid flux due to thermal gradient is also taken into account. The set of equations for the two‐phase heat and mass transfer is formulated fully considering diffusion, advection, and dispersion. The advantage of the proposed model over the traditional equation system is discussed. The accuracy of the proposed model is assessed through comparison with analytical work for coupled mass and heat transfer and experimental work for isothermal two‐phase flow (moisture/air transfer). The influence adding airflow has on the coupled moisture and heat transfer is further investigated, clearly identifying the importance of including airflow in the coupled mass and heat transfer. How the isothermal two‐phase flow is affected by considering heat flow is also evaluated, showing the influence of heat flow only to be significant if the air phase plays a significant role in solving the equations of the water phase. On the basis of a field experiment, the proposed model is compared with the measured soil moisture, temperature, and evaporation rate, the results showing clearly that it is necessary to consider the airflow mechanism in soil‐atmosphere interaction studies. Key Points Airflow is important in land surface models Heat flow must be considered when gas‐phase effect is strong Airflow influences the subsurface mass and heat transport

Geothermal heat flow (GHF) is a key basal boundary condition for Antarctic ice‐sheet flow. Large‐scale variations are resolved by several recent models but knowledge of the smaller‐scale variations, crucial for ice sheet dynamics, is limited by unresolved variations in crustal radiogenic heat production. To define this at continent‐scale we use 3D gravity inversion constrained by seismic Moho estimates to identify variations in crustal composition and geometry beneath thick ice. Geochemically‐defined empirical relationships between density and heat production capture the global average trend and its variability, and allow to estimate from upper‐crust density spatial variations in radiogenic heat production. Significant variations are observed typically 1.2–1.6 μW/m3, and as high as 2 μW/m3 in West Antarctica. The contribution to GHF from these heat‐production variations is similarly variable, typically 16–24 mW/m2 and up to 60 mW/m2. The mapped variations are significant for correctly representing GHF in Antarctica. Plain Language Summary Antarctica's crustal structure ‐ including sedimentary basins, the igneous and metamorphic crust, and the interface between the crust and mantle ‐ dictates the delivery of heat from depth to the ice sheet's base, with capacity to influence ice sheet flow. Crustal structure is not well‐understood due to the extensive and thick ice cover combined with limited geophysical observations. We investigate the variations in crustal geometry and density, by examining anomalies in the Earth's gravity field and using independent depth constraints from seismic studies. Our findings indicate substantial variations in heat production characterized by heterogeneous crustal structure, influencing the heating of the ice sheet's base to a significant degree. Key Points A new Antarctic crustal model is derived by seismic‐constrained gravity inversion Variations in crustal radiogenic heat production are inferred from upper‐crust density and geochemical data The potential impact of heterogeneity in crustal heat production for geothermal heat flow is quantified

In their study, Young et al. (2025, https://doi.org/10.1029/2025GL115729) employ airborne radio‐echo sounding data to map the basal unit over the East Antarctic Ice Sheet over a large area between Dome A and South Pole. The authors use the results to infer conclusions about ice‐dynamic behavior of the ice sheet, geology, temporal development of subglacial geomorphology and physical properties of ice and the subsurface in this region. A comparative study has not been performed before. The results are of relevance for a number of disciplines and objectives, among them the quest for finding an ice‐core site to yield a record older than 1 million years, constraining the basal boundary conditions for ice‐flow modeling as well as determining subglacial geology to improve geothermal heat flow estimates.

Accurate estimates of geothermal heat flow (GHF) are critical for predicting basal melting and identifying stable sites for ancient ice, yet GHF remains one of the least constrained boundary conditions for the Antarctic Ice Sheet. We evaluate nine published Antarctic GHF models against radar‐derived specularity content in the South Pole Basin (SPB), a geologically complex region in central East Antarctica. We also simulate an ensemble of synthetic GHF fields via a three‐parameter Markov Chain Monte Carlo algorithm to constrain the spatial variability required to match observed bed conditions. No existing GHF map captures the observed gradient in basal conditions significantly better than a uniform GHF field. Instead, the radar observations require a spatial GHF gradient aligned with a major ice‐sheet and geomorphological boundary within the SPB. Constraining basal thermal state in this region will require methods sensitive to shallow crustal heterogeneity and integration of radar‐based indicators directly into model frameworks.

Geothermal heat flow is a key parameter in governing ice dynamics, via its influence on basal melt and sliding, englacial rheology, and erosion. It is expected to exhibit significant lateral variability across Antarctica. Despite this, surface heat flow derived from Earth's interior remains one of the most poorly constrained parameters controlling ice sheet evolution. To obtain a continent‐wide map of Antarctic heat supply at regional‐scale resolution, we estimate upper mantle thermomechanical structure directly from VS. Until now, direct inferences of Antarctic heat supply have assumed constant crustal composition. Here, we explore a range of crustal conductivity and radiogenic heat production values by fitting thermodynamically self‐consistent geotherms to their seismically inferred counterparts. Independent estimates of crustal conductivity derived from VP are integrated to break an observed trade‐off between crustal parameters, allowing us to infer Antarctic geothermal heat flow and its associated uncertainty. Plain Language Summary The future evolution of the Antarctic Ice Sheet depends on its stability, which describes how sensitive it is to environmental change. A key factor influencing ice sheet stability is how much thermal energy is transferred into its base from Earth's interior: a parameter called geothermal heat flow. If the level of heat supply is high, melting at the base of the ice sheet is encouraged, resulting in enhanced sliding toward outlet glaciers at the continental perimeter. Consequently, ice loss is accelerated, and the likelihood of glacial collapse is increased. Therefore, an accurate map of Antarctic geothermal heat flow, including how this parameter varies from region to region, is needed to produce high quality projections of Antarctic ice mass loss and therefore global sea level change. In this study, we use models of how seismic wave speed varies within Earth to estimate its three‐dimensional temperature structure, as well as its thermal conductivity. These data are used to infer a collection of best‐fitting models of Earth's thermal state, and hence estimate Antarctic geothermal heat flow. Key Points Demonstration of new methodology for inferring geothermal heat flow from seismological data S‐ and P‐wave velocity used together to infer and fit geotherms Incorporation of laterally varying crustal conductivity and heat production

Consumers expect high-performance functionality from sportswear. To meet athletic and leisure-time activity requirements, further research needs to be carried out. Sportswear layers and their specific thermal qualities, as well as the set and air layer between materials, are all important factors in sports clothing. This research aims to examine the thermal properties of sports fabrics, and how they are affected by structure parameters and maintained with different layers. Three inner and four outer layers of fabric were used to make 12 sets of sportswear in this study. Before the combination of outer and inner layers, thermal properties were measured for each individual layer. Finally, the thermal resistance, thermal conductivity, thermal absorptivity, peak heat flow density ratio, stationary heat flow density, and water vapor permeability of bi-layered sportswear were evaluated and analyzed. The findings show that sportswear made from a 60% cotton/30% polyester/10% elastane inner layer and a 100% polyester outer layer had the maximum thermal resistance of 61.16 (×103 K·m2 W−1). This performance was followed by the sample made from a 90% polyester/10% elastane inner layer and a 100% polyester outer layer, and the sample composed of a 100% elastane inner layer and a 100% polyester outer layer, which achieved a thermal resistance value of 60.41 and 59.41 (×103 K·m2 W−1), respectively. These results can be explained by the fact that thicker textiles have a higher thermal resistance. This high-thermal-resistance sportswear fabric is appropriate for the winter season. Sportswear with a 90% polyester/10% elastane inner layer had worse water vapor resistance than sportswear with a 60% cotton/30% polyester/10% elastane and a 100% elastane layer. Therefore, these sports clothes have a higher breathability and can provide the wearers with very good comfort. According to the findings, water vapor permeability of bi-layered sportswear is influenced by geometric characteristics and material properties.

Improving the thermal insulation performance of buildings is crucial for saving energy. Currently, the insulation performance can be quantified based on the thermal resistance and thermal transmittance (U-value). However, for owners, these data are not readily available for the verification of different insulation methods. To address this, a solution could involve establishing a connection between specialized evaluation indicators and temperature, a common physical quantity. In this study, static and dynamic heat-transfer experiments were performed using an environmental simulation chamber and heat-flow sensors. Based on the tests, a simple predictive formula for the heat-flow density over time was established. After analyzing a full-scale building model, six cases of the heat-flow density versus temperature rise in indoor environments were obtained. This approach may aid owners in visually assessing the insulation performance of buildings by establishing a conversion relationship between the heat-flow density and temperature. In addition, the performance of 14 experimental specimens, including self-developed and code-documented thermal insulation materials and construction methods, was evaluated. In the simulations, after turning off indoor cooling equipment for 6 h during hot summers, the average indoor temperature increase for a roof with insulation was only 52% of that without insulation.