Journal of Geophysical Research: Planets最新文献

{"title":"Electron Densities in Jupiter's Upper Ionosphere Inferred From Juno Plasma Wave Observations","authors":"W. S. Kurth, J. B. Faden, J. H. Waite, A. H. Sulaiman, S. S. Elliott, G. B. Hospodarsky, J. E. P. Connerney, J. A. Kammer, T. Greathouse, P. Valek, F. Allegrini, F. Bagenal, T. Stallard, L. Moore, D. A. Coffin, O. Agiwal, P. Withers, S. J. Bolton","doi":"10.1029/2024JE008845","DOIUrl":"https://doi.org/10.1029/2024JE008845","url":null,"abstract":"<p>Juno's highly eccentric polar orbit takes it to perijove distances of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>1.06 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mi>J</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${mathrm{R}}_{J}$</annotation>\u0000 </semantics></math> on each orbit. For the first perijove, this occurred just north of the jovigraphic equator, but has precessed north by about a degree per orbit over the mission. Minimum altitudes vary from <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>3,200–8,000 km through the mission. The Waves instrument observes a number of plasma wave modes in and near the non-auroral ionosphere that provide information on the local electron number density, including electron plasma oscillations that occur at the electron plasma frequency <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>f</mi>\u0000 <mrow>\u0000 <mi>p</mi>\u0000 <mi>e</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${f}_{pe}$</annotation>\u0000 </semantics></math> and whistler-mode hiss which has an upper frequency limit of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>f</mi>\u0000 <mrow>\u0000 <mi>p</mi>\u0000 <mi>e</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${f}_{pe}$</annotation>\u0000 </semantics></math> in Jupiter's strongly magnetized inner magnetosphere. The electron plasma frequency provides the electron number density. We present electron densities in the topside ionosphere, similar to Earth's F2 layer, from the <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>59 perijoves analyzed to date. Peak densities range from <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 </mrow>\u0000 <annotation> ${sim} $</annotation>\u0000 </semantics></math>100 to 80,000 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 ","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008845","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamo Models With a Mercury-Like Magnetic Offset Dipole","authors":"P. Kolhey,&nbsp;D. Heyner,&nbsp;J. Wicht,&nbsp;T. Gastine,&nbsp;K.-H. Glassmeier,&nbsp;F. Plaschke","doi":"10.1029/2024JE008660","DOIUrl":"https://doi.org/10.1029/2024JE008660","url":null,"abstract":"<p>Mercury has a global magnetic field that is unique in our solar system. It is dominated by a weak axial dipole and a substantial axial quadrupole contribution. The field has a dipole tilt which is smaller than one degree and an offset of the magnetic equator toward north by about 20% of the planetary radius. The only dynamo model that succeeds in continuously reproducing these features without having to rely on an unrealistic heat-flux pattern through the core-mantle boundary is a double-diffusive model by Takahashi et al. (2019), https://doi.org/10.1038/s41467-018-08213-7, where thermal effects cause a thick, stably stratified layer in the outer parts of the core. In this study we further show the sensitivity of this model to the choice of parameters. In the explored parameter set, the model yields solutions which are unrealistic for Mercury when convection becomes vigorous. We present a new single-diffusive model, that captures Mercury's field characteristics during long periods that are interrupted by dipole field reversals causing the magnetic equator to switch between the northern and southern hemisphere. The Mercury-like solutions are stable over a broader range of parameters. An important ingredient for the success is the fact that dynamo action sets in with the equatorially symmetric magnetic field family.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008660","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparisons of Different Disk Functions Based on Laboratory Bidirectional Reflectance Measurements of Lunar-Type Minerals and Lunar Soils","authors":"Yazhou Yang,&nbsp;Te Jiang,&nbsp;Hao Zhang,&nbsp;Yang Liu,&nbsp;Yongliao Zou","doi":"10.1029/2024JE008693","DOIUrl":"https://doi.org/10.1029/2024JE008693","url":null,"abstract":"<p>In photometric modeling, disk function plays a crucial role in describing scattering behaviors related to the local incidence and emission angles of an observed surface. Finding a proper disk function is important for normalizing spectra observed under different observing geometries. This study evaluates the performances of five different disk functions, including the Lommel-Seeliger function, and functions proposed by Minnaert, McEwen, and Akimov, using bidirectional reflectance distribution function (BRDF) data of lunar-type minerals and Apollo lunar soils. BRDF measurements of olivine, orthopyroxene, plagioclase, and ilmenite were conducted to examine the effects of mineralogy and particle size. Our results indicate that the Akimov empirical function is most effective in reducing discrepancies among data measured under varied incidence and emission angles for both pure minerals and lunar soil samples. Two empirical functions for the free parameter <i>q</i> in this model were generalized based on pure mineral data, but are unsuitable for lunar soil samples. The <i>q</i> derived for six Apollo lunar soil samples are much lower than those for pure silicate minerals but align well with remote sensing observations, with no distinct differences between lunar mare and highland soil samples, possibly due to extensive space weathering on the lunar surface. The <i>q</i> values at a phase angle of 70° show the strongest correlation with the widely used maturity index <i>I</i>_s/FeO, and two empirical functions between <i>I</i>_s/FeO and <i>q</i>(70°) for bands 550 and 750 nm were established, which may be used to quantify the degree of space weathering.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climatology of the Residual Mean Circulation of the Martian Atmosphere and Contributions of Resolved and Unresolved Waves Based on a Reanalysis Data Set","authors":"Anzu Asumi,&nbsp;Kaoru Sato,&nbsp;Masashi Kohma,&nbsp;Yoshi-Yuki Hayashi","doi":"10.1029/2023JE008137","DOIUrl":"https://doi.org/10.1029/2023JE008137","url":null,"abstract":"<p>The objective of this study is to examine the climatology of the residual mean circulation, and the roles of wave forcings by both resolved waves (RWs) and unresolved waves (UWs). The analysis is performed using data from the Ensemble Mars Atmosphere Reanalysis System (EMARS) over four Mars Years without global dust storms, based on the transformed Eulerian mean equation theory. While the RW forcing is estimated directly as Eliassen-Palm flux divergence, the forcing by UWs, including subgrid-scale gravity waves, is estimated indirectly using the zonal momentum equation. This indirect method, originally devised for studying the Earth's middle atmosphere, is applicable to latitudinal ranges where angular momentum isopleths are continuous from the surface to the top of the atmosphere, typically mid- and high-latitude regions. In low latitudes of the winter hemisphere, a strong residual mean flow toward the winter pole is observed in a pressure range between ∼20 and ∼0.5 Pa (∼30–60 km), where the latitudinal gradient of the absolute angular momentum is small. The strong poleward flow crosses the isopleths of angular momentum in the regions of its northern and southern ends, indicating the necessity of the wave forcing. Our results suggest that the structure of the residual mean circulation at mid- and high-latitude regions is largely determined by UW forcing, particularly above ∼2 Pa level, whereas the RW contribution is also significant below the ∼2 Pa level.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008137","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aerosol Climatology on Mars as Observed by NOMAD UVIS on ExoMars TGO","authors":"Z. Flimon,&nbsp;J. Erwin,&nbsp;S. Robert,&nbsp;L. Neary,&nbsp;A. Piccialli,&nbsp;L. Trompet,&nbsp;Y. Willame,&nbsp;F. Vanhellemont,&nbsp;F. Daerden,&nbsp;S. Bauduin,&nbsp;M. Wolff,&nbsp;I. R. Thomas,&nbsp;B. Ristic,&nbsp;J. P. Mason,&nbsp;C. Depiesse,&nbsp;M. R. Patel,&nbsp;G. Bellucci,&nbsp;J.-J. Lopez-Moreno,&nbsp;A. C. Vandaele","doi":"10.1029/2024JE008303","DOIUrl":"https://doi.org/10.1029/2024JE008303","url":null,"abstract":"<p>The Nadir and Occultation for MArs Discovery spectrometer on board Trace Gas Orbiter began science operations in April 2018, providing infrared and ultraviolet-visible spectra of the Martian atmosphere. This paper explores the application of the UVIS channel in solar occultation to study aerosols. We have developed a retrieval scheme that allows us to study the size and extinction of the aerosol as a function of altitude. Results from mid-MY 34 to the end of MY 36 are reported and discussed. Particle size is retrieved using a Mie code with log-normal distribution with an effective radius (<i>r</i>_eff), 0.1–0.8 μm and an effective variance (<i>v</i>_eff) equal 0.1. In this work, we show the presence of aerosol-detached layers, characterized by a local increase in particle size and extinction. These detached layers can be composed of dust, H₂O ice, or CO₂ ice. CO₂ ice clouds can be detected up to 80 km, while H₂O ice clouds are usually more present around 30–50 km. Symmetry of the particle effective radius between the northern and southern regions is observed. During northern/southern winter, the atmospheric aerosols are composed of smaller particles below 0.6 μm but in summer, the size increases to micron-sized particles that are larger than the sensitivity of UVIS. This increase in size in the northern/southern summer is not correlated with a similar increase in extinction. Our data support the previously observed relationship between water vapor and aerosol, especially the formation of high-altitude water ice cloud during the global dust storm event.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008303","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric Gravity Waves in Mars' Lower Atmosphere: Nadir Observations From OMEGA/Mars Express Data","authors":"F. Brasil,&nbsp;P. Machado,&nbsp;G. Gilli,&nbsp;A. Cardesín-Moinelo,&nbsp;J. E. Silva,&nbsp;D. Espadinha,&nbsp;L. Riu,&nbsp;J. Carter,&nbsp;C. Wilson","doi":"10.1029/2024JE008726","DOIUrl":"https://doi.org/10.1029/2024JE008726","url":null,"abstract":"<p>We present the detection and characterization of mesoscale waves on the lower clouds of Mars (20–40 km) using hyperspectral images from the Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité (OMEGA) onboard the European Mars Express space mission. We used image navigation and processing techniques based on contrast enhancement and geometrical projections to semi-manually detect and manually characterize morphological properties of the detected waves, such as horizontal wavelength or packet length. Our study covers 3 Martian years, spanning from January 2004 (Mars Year 26) to January 2010 (Mars Year 29). We detected 263 wave packets, of which we characterized 125, revealing an average horizontal wavelength of 21 km, with detected waves spanning horizontal wavelengths between 6 and 83 km. Wave activity exhibited spatial and temporal variability, with larger wave packets concentrated in the northern hemisphere and most detections occurring during daytime. Seasonal patterns revealed higher wave activity during northern spring and autumn and southern winter, linked to regional topography, atmospheric density perturbations, and diurnal heating cycles. These findings provide insights into Martian atmospheric gravity waves and demonstrate the OMEGA data set's value for future studies of Mars's atmospheric dynamics.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Phase Evolution and Composition Variations of Volcanic Activities on the Lunar Farside Revealed by Chang'e-4 Lunar Penetrating Radar","authors":"Huaqing Cao,&nbsp;Jing Li,&nbsp;Yi Xu,&nbsp;Chang Zhang","doi":"10.1029/2024JE008740","DOIUrl":"https://doi.org/10.1029/2024JE008740","url":null,"abstract":"<p>Volcanism is the primary endogenic geological process on the Moon, with mare basalts being the critical indicators of such activity. The abundance of titanium in these mare basalts reflects different lunar mantle sources, magma origins, and thermal evolution processes. The Chang'e-4 mission, which landed in the Von Kármán crater within the South Pole-Aitken Basin on the farside of the Moon, employed a lunar penetrating radar with a low-frequency channel to reveal the subsurface structures and abundance of FeO and TiO₂ of these structures down to approximately 300 m. The dielectric properties and iron-titanium content are crucial for interpreting basalt units. This study utilizes radar wave-impedance inversion to derive the permittivity from the low-frequency lunar penetrating data collected during the first 62 lunar days. The frequency shift method was used to calculate the loss tangent and estimate the abundance of FeO and TiO₂ in the subsurface materials at the landing area. Based on permittivity, variations in abundance of FeO and TiO₂, and impact crater statistics near the landing site, we infer at least four distinct periods of magma with varying FeO and TiO₂ beneath the Chang'e-4 landing site, spanning from the Nectarian to the Eratosthenian periods. High titanium and medium titanium basalts were found in the Nectarian and Imbrian periods. This study reveals the evolutionary process of multi-phase volcanic eruptions on the farside of the Moon, indicating not only temporal but also compositional variations in volcanic activities, thereby highlighting the complexity of volcanic processes on the lunar farside.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143533382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Map of Jupiter's Radiation Environment From Juno's In-Situ Observations","authors":"M. Herceg,&nbsp;T. Denver,&nbsp;J. Sushkova,&nbsp;J. L. Jørgensen,&nbsp;M. Benn,&nbsp;L. Ghizoni,&nbsp;P. S. Jørgensen,&nbsp;S. Kotsiaros,&nbsp;J. E. P. Connerney,&nbsp;S. J. Bolton","doi":"10.1029/2024JE008549","DOIUrl":"https://doi.org/10.1029/2024JE008549","url":null,"abstract":"<p>Since its orbit insertion on 4 July 2016, the Juno spacecraft has orbited Jupiter in a highly elliptical, polar orbit. With every orbit, Juno's line of apsides migrates, increasing the angle relative to the Jovian equator. Therefore, the spacecraft traverses across the inner regions of the radiation belt, where energetic particles are trapped. The most energetic particle fluxes (electrons with energy &gt;20 MeV) are continuously monitored by an instrument that is part of the Magnetic Field investigation, the micro Advanced Stellar Compass (μASC), which serves as an attitude reference for the magnetic sensor. In the regions traversed thus far in the mission, the μASC has obtained in-situ measurements of high-energy particle fluxes from those on open field lines to Io's L-shell, densely covering the flux environment. We present a map of the radiation environment within Jupiter's magnetosphere based on in-situ measurements acquired in regions not well sampled by prior missions.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008549","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro-CT Characterization of the Chang'e-5 Lunar Regolith Samples","authors":"Huanyu Wu,&nbsp;Yuan Zou,&nbsp;Chi Zhang,&nbsp;Wei Yang,&nbsp;Bo Wu,&nbsp;Kai-Leung Yung,&nbsp;Qi Zhao","doi":"10.1029/2024JE008787","DOIUrl":"https://doi.org/10.1029/2024JE008787","url":null,"abstract":"<p>Chang'e-5 (CE-5) lunar regolith samples were scanned using X-ray micro-computed tomography (micro-CT), and over 0.7 million particles were extracted from the images through machine learning-based segmentation. This is the largest three-dimensional (3D) image data set on lunar regolith particles to date, offering a unique opportunity to study the key characteristics of the lunar regolith. The image intensity was correlated with mineral density, allowing for the assessment of the bulk density (1.58 g/cm³), true density (3.17 g/cm³), and mineralogy of the lunar regolith. Glass and plagioclase contributed 45.6 wt.% of the samples, while pyroxene and olivine made up 49.7 wt.%, and ilmenite accounted for 4.7 wt.%. The median grain size of CE-5 was 57.5 μm, smaller than the Apollo 11, 16 and Luna 16, 20 and 24 samples. Spherical harmonic (SH) analysis and aspect ratio (AR) measurement revealed that the CE-5 lunar regolith particles have more complex shapes than two common terrestrial soils and exhibit less spherical shapes than Apollo 11, 16 and Luna 16, 20 and 24 samples. We recommend using size and shape characteristics cautiously when inferring the lunar regolith maturity because the intrinsic crystal size of the protolith and complex lunar surface weathering can cause significant size and shape variations. Additionally, characterizing particle shapes requires a large sample size (&gt;1,000) to prevent skewed results from outliers. Our non-destructive examination method offers a novel and appealing approach for analyzing critical physical, mineralogical, and morphological properties of million-scale extraterrestrial soil particles, paving the way for future deep space explorations.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 3","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008787","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Large Water Inventory in Highly Adsorptive Regolith Simulated With a Mars Global Climate Model","authors":"M. Kobayashi,&nbsp;A. Kamada,&nbsp;T. Kuroda,&nbsp;H. Kurokawa,&nbsp;S. Aoki,&nbsp;H. Nakagawa,&nbsp;N. Terada","doi":"10.1029/2024JE008697","DOIUrl":"https://doi.org/10.1029/2024JE008697","url":null,"abstract":"<p>This study explores the subsurface water distribution near the surface throughout Mars, using a Mars Global Climate Model (MGCM). We coupled a regolith model that solves the equations of water transport, adsorption, and condensation in the regolith with our MGCM to investigate the effects of inhomogeneous regolith properties on the subsurface water distribution. This regolith model includes a regolith property model that calculates inhomogeneous regolith properties (grain size, porosity, and adsorption coefficient) based on the results of laboratory experiments. The simulations were performed with five different regolith situations over 500 Martian years, aiming for a quasi-steady state of adsorbed water concentration within the top meters of the regolith. Our results revealed a high adsorbed water concentration near the equator (2.0–4.0 kg m⁻² for depths within 2 m, with a high adsorption coefficient of ∼200 kg m⁻³), which was caused by the highly adsorbed regolith, which has a large specific surface area. This indicates the nonnegligible effects of the spatial inhomogeneity of the adsorption coefficient on the adsorbed water distribution. Highly adsorptive regolith also promotes pore ice accumulation in shallower layers at high latitudes because in the winter the freezing of adsorbed water is faster than the water transport in the regolith. In the determination of long-term water retention and runoff on Mars, highly adsorptive regolith acts to retain subsurface water, decelerating water transport within the regolith because the water vapor concentration at equilibrium decreases with increasing adsorption coefficient. This study highlights the significant effects of regolith adsorbability on the subsurface water distribution.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008697","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}