Earth and Space Science最新文献

{"title":"Adaptive Super-Resolution for Ocean Bathymetric Maps Using a Deep Neural Network and Data Augmentation","authors":"Koshiro Murakami,&nbsp;Daisuke Matsuoka,&nbsp;Naoki Takatsuki,&nbsp;Mitsuko Hidaka,&nbsp;Junji Kaneko,&nbsp;Yukari Kido,&nbsp;Eiichi Kikawa","doi":"10.1029/2024EA003610","DOIUrl":"https://doi.org/10.1029/2024EA003610","url":null,"abstract":"<p>Machine learning-based image super-resolution is a robust approach for obtaining detailed bathymetric maps. However, in machine learning using supervised data, dissimilarities in the features of training and target data sets degrades super-resolution performance. In this study, we propose a two-step method to generate training data with features similar to those of the target data using image transformation and composition. The super-resolution model trained using the proposed method on the Central Okinawa Trough data was applied to the bathymetry data around Okinotorishima Islands. The method improved the root mean squared error by up to 14.3% without compromising spatial consistency compared with that observed using conventional approaches, thus demonstrating the potential of combining artificial data generation with machine learning for super-resolution bathymetry mapping of the entire ocean floor. The proposed method, independent of the characteristics of training data, is suggested as a potential alternative to acoustic measurements for expanding areas of detailed bathymetric maps.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA003610","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144085204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Gap Flows in Nares Strait: Multi-Scale Numerical Model Simulations in Comparison to Aircraft Measurements","authors":"Svenja H. E. Kohnemann,&nbsp;Günther Heinemann","doi":"10.1029/2024EA003912","DOIUrl":"https://doi.org/10.1029/2024EA003912","url":null,"abstract":"<p>The steep topography of Ellesmere Island and the northern Greenland coast, combined with a stable boundary layer, generates intense low-level winds in Nares Strait, that influence sea ice transport. In Smith Sound, a gap flow forms impacting the most productive North Water Polynya. We use the non-hydrostatic regional climate model CCLM with horizontal resolutions of 14, 5 and 1 km to study these processes for the period of an aircraft-based experiment in June 2010. Additionally, CARRA reanalysis is included. All model data resolve the small channel and represent the stable boundary conditions realistically. The highest winds of around 14 m <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>s</mi>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${mathrm{s}}^{-1}$</annotation>\u0000 </semantics></math> are present in the exit region of Smith Sound for June 2010. Comparisons with aircraft profiles for potential temperature and wind speed show small biases and correlations higher than 0.84 for CCLM, along with a good representation of the boundary layer structure. Increasing model resolution from 14 to 5 km yields notable improvements in the representation of these variables. CARRA data are similar or better than CCLM data, except for the potential temperature, where a relatively large warm bias was found. Maximum winds occur at gap exit region of Smith Sound and are associated with gravity waves generated by the barrier, resulting in downward flow within the gap. Model simulations offer the advantage of studying the temporal development and the full three-dimensional structure. The wind maximum is influenced by the gap flow structure for mountain Froude numbers less than 1 and by the position and intensity of a low pressure system in Baffin Bay.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA003912","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144074550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Enhancing Surface PM2.5 Air Quality Estimates in GEOS Using CATS Lidar Data","authors":"Alexander V. Matus,&nbsp;Edward P. Nowottnick,&nbsp;John E. Yorks,&nbsp;Arlindo M. da Silva","doi":"10.1029/2024EA004078","DOIUrl":"https://doi.org/10.1029/2024EA004078","url":null,"abstract":"&lt;p&gt;Spaceborne lidar offers unique advantages for improving global estimates of fine particulate matter (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;PM&lt;/mtext&gt;\u0000 &lt;mn&gt;2.5&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{PM}}_{2.5}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), traditionally limited by critical data gaps in the vertical dimension. Here, we present a new method to retrieve &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;PM&lt;/mtext&gt;\u0000 &lt;mn&gt;2.5&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{PM}}_{2.5}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; relying on ensembles on aerosol extinction available within the GEOS Aerosol Data Assimilation. This study uses 1064-nm backscatter lidar data from the NASA Cloud-Aerosol Transport System (CATS) and model priors from the GEOS model. First, we developed a 1-D ensemble-based variational technique (1-D EnsVar) to perform vertically resolved retrievals of speciated aerosol extinction and surface &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;PM&lt;/mtext&gt;\u0000 &lt;mn&gt;2.5&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{PM}}_{2.5}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;. Next, we evaluated the performance of 1-D EnsVar retrievals of &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;PM&lt;/mtext&gt;\u0000 &lt;mn&gt;2.5&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{PM}}_{2.5}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and extinction through an independent validation using measurements from spaceborne, airborne, and ground-based platforms. This approach overcomes traditional limitations by leveraging the strengths of complementary vertical aerosol information from CATS and GEOS to better resolve speciated aerosol optical properties and mass. Assimilating CATS lidar data with the GEOS model reduced bias in surface &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;PM&lt;/mtext&gt;\u0000 &lt;mn&gt;2.5&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{PM}}_{2.5}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; prediction by 1.1 &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;μ&lt;/mi&gt;\u0000 &lt;mi&gt;g&lt;/mi&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 ","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004078","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144074551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Improving “23.07” Heavy Rainstorm Simulation Through Assimilating FY-3E MWTS-3 Radiance Data","authors":"Shengjie Zhu,&nbsp;Deqin Li,&nbsp;Shibo Gao,&nbsp;Qian Xie,&nbsp;Xiao Pan","doi":"10.1029/2025EA004363","DOIUrl":"https://doi.org/10.1029/2025EA004363","url":null,"abstract":"<p>FengYun-3E (FY-3E) satellite, launched on 5 July 2021, is equipped with the third-generation Microwave Temperature Sounder (MWTS-3). Two window channels of MWTS-3 are used to build a cloud detection module, and efficient assimilation of MWTS-3 clear-sky radiance data is implemented in the Weather Research and Forecasting Model (WRF). To assess the influence of assimilating MWTS-3 radiances on extreme precipitation weather forecasting, a heavy rainstorm event that occurred in North China from 29 July to 2 August 2023, has been selected. After assimilating MWTS-3 radiance data, the geopotential height field adjusted, leading to a northwestward shift of the Western Pacific Subtropical High as well as an eastward adjustment of the weather system. The forecasts with assimilated MWTS-3 data reduced the root mean square error of temperature, zonal wind, and meridional wind, with clear improvements in temperature forecast skill at the 100–400 hPa levels within the first 33 hr of the forecast period. The 6–hr maximum rainfall center located southwest of Beijing was more successfully reproduced in the model simulation. Additionally, the precipitation forecast skill above the threshold of 15 mm was improved. Moreover, the water vapor transport and vertical motion conditions in Beijing has improved after assimilating MWTS-3 data, which are likely to be contributing factors to the enhancements in the precipitation forecasting performance.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025EA004363","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143949900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Advancements in the GRACE and GRACE-FO Gradiometer Mode","authors":"Nikeet Pandit,&nbsp;Spiros Pagiatakis","doi":"10.1029/2024EA004045","DOIUrl":"https://doi.org/10.1029/2024EA004045","url":null,"abstract":"<p>The global gravitational gradient field has not been observed since the decommission of GOCE in 2013. Based on the foundational work of Peidou and Pagiatakis (2019, https://doi.org/10.1029/2018jb016382), we advance the concept of GRACE gradiometer mode (GM) for the purpose of using GRACE, GRACE-FO and future gravity space missions as “gradiometer missions.” Certainly, the GRACE missions have never carried on board a gradiometer; it is the concept of GM that creates a fictitious gradiometer system very similar to GOCE, only the GRACE “gradiometers” have long and variable baselines, an unprecedented paradigm for space-based gravitational gradiometry that extends the bandwidth of available GOCE gradient solutions. In this contribution, we develop a new configuration for GM that views an individual satellite as the “gradiometer” by directly using Level 1A accelerometer measurements at a 10 Hz sampling rate. We apply the new method in geodynamically active regions around the globe, and we demonstrate that using GRACE-C as a “gradiometer” in the single-satellite gradiometer mode (SS-GM) produces higher-fidelity gravitational gradient estimates, clearly delineating tectonic plate boundaries and subduction zones in the Himalayas and North Africa regions, the Aleutian trench, the Java trench, and the Peru-Chile trench. Over Canada, we see the delineation of the Canadian shield, and the effect of glacial isostatic adjustment is apparent. We also observe well-known signals resembling terrestrial water storage changes in Africa, among others, demonstrating the usefulness of the GM for a wide variety of geoscience applications.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143939161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"The Mechanism of Seasonal Variation in Sea Surface Height in the Bohai Sea","authors":"Siyu Liu,&nbsp;Guangxue Li,&nbsp;Shidong Liu,&nbsp;Lei Zhang,&nbsp;Lvyang Xing,&nbsp;Yufeng Pan,&nbsp;Di Yu","doi":"10.1029/2024EA003690","DOIUrl":"https://doi.org/10.1029/2024EA003690","url":null,"abstract":"<p>The Bohai Sea, located at the edge of western Pacific, is one of the most vulnerable regions under climate change. Using the high-precision MIKE three-dimensional hydrodynamic numerical model, this study conducted comparative experiments to investigate the impacts of atmospheric pressure, wind, specific volume, and evaporation precipitation and runoff on the seasonal variations of the sea surface height (SSH) in the Bohai Sea. The findings reveal that the average annual SSH in the Bohai Sea is lower in the northeast and higher in the southwest, higher in summer and lower in winter. Moreover, the seasonal SSH variation decreases from north to south, with variations exceeding 0.4 m in the northern Liaodong Bay but only 0.2 m in the southern Laizhou Bay. Atmospheric pressure emerges as a significant factor, contributing 72.7%, 73.9%, 71.0%, and 92.0% to the seasonal SSH changes in Liaodong Bay, Laizhou Bay, Bohai Bay, and the Bohai Strait, respectively, and causing seasonal SSH difference of approximately 0.22 m in most areas. Specific volume changes contribute 6.1%, 21.7%, 19.3%, and 4.0% to the seasonal SSH variations in the respective regions. Wind direction impacts result in lower SSH in the northern Bohai Sea during winter and higher SSH in summer, while the southern part exhibits the opposite trend. This study evaluates the contribution of each factor to seasonal SSH changes, and provides reference for other areas, which improves the accuracy of engineering design and non-period water level forecasts, and evaluates potential climate changes affecting marine environments.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA003690","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143919722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Deriving WMO Cloud Classes From Ground-Based RGB Pictures With a Residual Neural Network Ensemble","authors":"Markus Rosenberger,&nbsp;Manfred Dorninger,&nbsp;Martin Weissmann","doi":"10.1029/2024EA004112","DOIUrl":"https://doi.org/10.1029/2024EA004112","url":null,"abstract":"<p>Clouds of various kinds play a substantial role in a wide variety of atmospheric processes. They are directly linked to the formation of precipitation, and significantly affect the atmospheric energy budget via radiative effects and latent heat. Moreover, knowledge of currently occurring cloud types allows the observer to draw conclusions about the short-term evolution of the state of the atmosphere and the weather. Therefore, a consistent cloud classification scheme has already been introduced almost 100 years ago. In this work, we train an ensemble of identically initialized multi-label residual neural network architectures from scratch with ground-based RGB pictures. Operational human observations, consisting of up to three out of 30 cloud classes per instance, are used as ground truth. To the best of our knowledge, we are the first to classify clouds with this methodology into 30 different classes. Class-specific resampling is used to reduce prediction biases due to a highly imbalanced ground truth class distribution. Results indicate that the ensemble mean outperforms the best single member in each cloud class. Still, each single member clearly outperforms both random and climatological predictions. Attributes diagrams indicate underconfidence in heavily augmented classes and very good calibration in all other classes. Autonomy and output consistency are the main advantages of such a trained classifier, hence we consider operational cloud monitoring as main application. Either for consistent cloud class observations or to observe the current state of the weather and its short time evolution with high temporal resolution, for example, in proximity of solar power plants.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004112","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143901051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Characteristics of Equatorial Electrojet Derived From MSS1A Observation: Initial Result","authors":"Yuyang Huang,&nbsp;Chao Xiong,&nbsp;Fengjue Wang,&nbsp;Xinyi Rang,&nbsp;Yunliang Zhou,&nbsp;Bohao Qian,&nbsp;Qing Yan,&nbsp;Kuan Li,&nbsp;Keke Zhang,&nbsp;Yanyan Yang","doi":"10.1029/2024EA004096","DOIUrl":"https://doi.org/10.1029/2024EA004096","url":null,"abstract":"<p>In this study, we use the magnetic field data from the Coupled Dark State Magnetometer (CDSM) aboard the Macau Science Satellite-1A (MSS1A) to calculate and analyze the equatorial electrojet (EEJ) in the period between November 2023 and December 2024. The inverse method, initially developed for polar-orbiting satellites, is evaluated for its applicability to the MSS1A, which features a distinct 41° orbital inclination. For the observational time window, there are 6251 electrojet events selected for analysis. We find that the median current density profile peaks at the magnetic equator, with a median peak value of 35 mA/m. The current density distribution is relatively concentrated, with a half-maximum width of approximately 5° in magnetic latitude. The data set comprises the eastward and westward EEJ events in a ratio between 79% and 21%, respectively. We also have examined the EEJ dependence on solar activity level, local time, longitude, season, and magnetic activity. The peak current density of the EEJ increases as the P10.7 index rises from 140 to 220 solar flux units. The peak density of EEJ is mostly pronounced around noon and varies with season, with high amplitudes observed during equinoxes and low values during solstices. The averaged peak current density of the EEJ displayed a distinct longitudinal wave number 4 pattern, which should be attributable to non-migrating tides originating from the lower atmosphere. In general, from both event-based and statistical analyses, the EEJ characteristics observed by MSS1A agree well with that observed by previous satellites, for example, Swarm, suggesting that the magnetic measurements from the newly launched MSS provide a new data set for monitoring the ionospheric currents.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Guide for Conducting “Community Challenges” in Space Physics","authors":"Michael W. Liemohn,&nbsp;Lutz Rastätter,&nbsp;Alexa J. Halford,&nbsp;Yihua Zheng,&nbsp;Katherine S. Garcia-Sage,&nbsp;Robert Redmon,&nbsp;Sarah K. Vines","doi":"10.1029/2024EA004138","DOIUrl":"https://doi.org/10.1029/2024EA004138","url":null,"abstract":"<p>The Geospace Environment Modeling (GEM) program regularly issues “community challenges” in which researchers examine a particular space physics phenomenon or geomagnetic activity event, often running numerical models to assess dominant processes and understand the timing and relationship of observed signatures. The GEM Methods and Validation Resource Group helps those GEM focus group leaders running challenges to maximize participation and optimize scientific return from the significant time investment of these endeavors. This article gives a brief history of GEM community challenges and details those best practices that lead to an inclusive and valuable experience.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA004138","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Investigation of Gas-Surface Interactions and Neutral Atmospheric Properties and Their Impact on Satellite Drag Coefficients","authors":"Soumyajit Dey,&nbsp;Phillip C. Anderson,&nbsp;Aaron L. Bukowski,&nbsp;Marcin D. Pilinski","doi":"10.1029/2024EA003998","DOIUrl":"https://doi.org/10.1029/2024EA003998","url":null,"abstract":"<p>Changes in the thermospheric composition and temperature influence satellite drag coefficients through functional dependencies in the closed-form solutions, and gas-surface interactions via accommodation coefficients. This study investigates drag coefficient variations for the Gravity Recovery And Climate Experiment (GRACE) and Communications/Navigation Outage Forecasting System (C/NOFS) satellites under varying atmospheric conditions and satellite orientations. The closed-form solutions of Diffuse Reflection and Incomplete Accommodation (DRIA) and Cercignani-Lampis-Lord (CLL) gas-surface interaction models have been used to calculate the drag coefficients. The momentum and energy accommodation coefficients, derived using empirical models, are used as input variables in the closed-form solutions to specify the nature of the gas-surface interactions. The results provide a realistic view of drag coefficient variations for the atmospheric changes observed for low-Earth orbit satellites. The analysis reveals that increasing the atomic oxygen mole fraction leads to significant decreases in the drag coefficients, with CLL showing greater variability than DRIA. The variability of the drag coefficients with neutral temperature demonstrates a strong dependence on satellite shapes, with GRACE drag coefficients increasing with temperature while C/NOFS drag coefficients decrease. Analysis of the C/NOFS orbits demonstrates drastic changes in the gas-surface interactions, transitioning from oxygen-dominated diffuse scattering at lower altitudes to helium-dominated quasi-specular interactions at higher altitudes. These variations persist during the September 2011 geomagnetic storm, with slightly reduced drag coefficients during storm-time conditions compared to quiet periods. The GRACE drag coefficients are highly sensitive to pitch and yaw angle variations, while the C/NOFS drag coefficients show minimal sensitivity due to its more symmetrical geometry.</p>","PeriodicalId":54286,"journal":{"name":"Earth and Space Science","volume":"12 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EA003998","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}