Journal of Advances in Modeling Earth Systems最新文献

{"title":"Experimental Soil Warming Impacts Soil Moisture and Plant Water Stress and Thereby Ecosystem Carbon Dynamics","authors":"W. J. Riley,&nbsp;J. Tao,&nbsp;Z. A. Mekonnen,&nbsp;R. F. Grant,&nbsp;E. L. Brodie,&nbsp;E. Pegoraro,&nbsp;M. S. Torn","doi":"10.1029/2024MS004714","DOIUrl":"https://doi.org/10.1029/2024MS004714","url":null,"abstract":"<p>Experimental soil heating experiments have found a consistent increase in soil-surface CO₂ emissions (<i>F</i>_<i>s</i>), but inconsistent soil organic carbon (SOC) responses. Interpretation of heating effects is complicated by spatial heterogeneity and soil moisture, nitrogen availability, and microbial and plant responses. Here we applied a mechanistic ecosystem model to interpret heating impacts on a California forest subjected to 1 m deep, 4°C heating. The model accurately simulated control-plot CO₂ fluxes, SOC stocks, fine root biomass, soil moisture, and soil temperature, and the observed increases in <i>F</i>_<i>s</i> and decreases in fine root biomass. We show that a complex suite of interactions can lead to a consistent increase in <i>F</i>_<i>s</i> (∼17%) over the 5-year study period, with very small changes in SOC stocks (&lt;1%). Modeled increases in leaf water stress from soil drying reduced GPP and NPP. The resulting reduction in leaf and fine root allocation increased fine root litter inputs to the soil and reduced root exudation. Soil heating led to about a 50% larger increase in root autotrophic respiration than in heterotrophic respiration, with the heating effect on both these fluxes decreasing over the simulation period. Increased heterotrophic respiration led to increased soil N availability and plant N uptake. These heating responses are mechanistically linked, of magnitudes that can affect ecosystem dynamics, and long-term observations of them are rarely made. Therefore, we conclude that a coupled observational and mechanistic modeling framework is needed to interpret manipulation experiments, and to improve projections of climate change impacts on terrestrial ecosystem carbon dynamics.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 2","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004714","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143186347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"ELM-Wet: Inclusion of a Wet-Landunit With Sub-Grid Representation of Eco-Hydrological Patches and Hydrological Forcing Improves Methane Emission Estimations in the E3SM Land Model (ELM)","authors":"Theresia Yazbeck,&nbsp;Gil Bohrer,&nbsp;Madeline E. Scyphers,&nbsp;Justine E. C. Missik,&nbsp;Oleksandr Shchehlov,&nbsp;Eric J. Ward,&nbsp;Sergio L. Merino,&nbsp;Robert Bordelon,&nbsp;Diana Taj,&nbsp;Jorge A. Villa,&nbsp;Kelly Wrighton,&nbsp;Qing Zhu,&nbsp;William J. Riley","doi":"10.1029/2024MS004396","DOIUrl":"https://doi.org/10.1029/2024MS004396","url":null,"abstract":"<p>Wetlands are the largest emitters of biogenic methane (CH₄) and represent the highest source of uncertainty in global CH₄ budgets. Here, we aim to improve the realism of wetland representation in the U.S. Department of Energy's Exascale Earth System Model land surface model, ELM, thereby reducing uncertainty of CH₄ flux predictions. We develop an updated version, ELM-Wet, where we activate a separate landunit for wetlands that handles multiple wetland-specific eco-hydrological patch functional types. We introduce more realistic hydrological forcing through prescribing site-level constraints on surface water elevation, which allows resolving different sustained inundation depth for different patches, and if data exists, prescribing inundation depth. We modified the calculation of aerenchyma transport diffusivity based on observed conductance per leaf area for different vegetation types. We use Bayesian Optimization to parameterize CO₂ and CH₄ fluxes in the developed wet-landunit. Site-level simulations of a coastal non-tidal freshwater wetland in Louisiana were performed with the updated model. Eddy covariance observations of CO₂ and CH₄ fluxes from 2012 to 2013 were used to train the model and data from 2021 were used for validation. Patch-specific chamber flux observations and observations of CH₄ concentration profiles in the soil porewater from 2021 were used for evaluation of the model performance. Our results show that ELM-Wet reduces the model's CH₄ emission root mean squared error by up to 33% and is able to represent inter-daily CO₂ and CH₄ flux variability across the wetland's eco-hydrological patches, including during periods of extreme dry or wet conditions.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 2","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004396","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"LEMDA: A Lagrangian-Eulerian Multiscale Data Assimilation Framework","authors":"Quanling Deng,&nbsp;Nan Chen,&nbsp;Samuel N. Stechmann,&nbsp;Jiuhua Hu","doi":"10.1029/2024MS004259","DOIUrl":"https://doi.org/10.1029/2024MS004259","url":null,"abstract":"<p>Lagrangian trajectories are widely used as observations for recovering the underlying flow field via Lagrangian data assimilation (DA). However, the strong nonlinearity in the observational process and the high dimensionality of the problems often cause challenges in applying standard Lagrangian DA. In this paper, a Lagrangian-Eulerian multiscale DA (LEMDA) framework is developed. It starts with exploiting the Boltzmann kinetic description of the particle dynamics to derive a set of continuum equations, which characterize the statistical quantities of particle motions at fixed grids and serve as Eulerian observations. Despite the nonlinearity in the continuum equations and the processes of Lagrangian observations, the time evolution of the posterior distribution from LEMDA can be written down using closed analytic formulas after applying the stochastic surrogate model to describe the flow field. This offers an exact and efficient way of carrying out DA, which avoids using ensemble approximations and the associated tunings. The analytically solvable properties also facilitate the derivation of an effective reduced-order Lagrangian DA scheme that further enhances computational efficiency. The Lagrangian DA part within the framework has advantages when a moderate number of particles is used, while the Eulerian DA part can effectively save computational costs when the number of particle observations becomes large. The Eulerian DA part is also valuable when particles collide, such as using sea ice floe trajectories as observations. LEMDA naturally applies to multiscale turbulent flow fields, where the Eulerian DA part recovers the large-scale structures, and the Lagrangian DA part efficiently resolves the small-scale features in each grid cell via parallel computing. Numerical experiments demonstrate the skillful results of LEMDA and its two components.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 2","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004259","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Development of a Data-Driven Lightning Scheme for Implementation in Global Climate Models","authors":"Vincent Verjans,&nbsp;Christian L. E. Franzke","doi":"10.1029/2024MS004464","DOIUrl":"https://doi.org/10.1029/2024MS004464","url":null,"abstract":"&lt;p&gt;This study proposes a new lightning scheme applicable at the global scale, predicting lightning rates from climatic variables. Using satellite lightning records spanning a period of 29 years, we apply machine learning methods to derive a functional relationship between lightning and climate reanalysis data. In particular, we design a tree-based regression scheme, representing different lightning regimes with separate single hidden layer neural networks of low dimensionality. We apply multiple complexity constraints in the development stages, which makes our lightning scheme straightforward to implement within global climate models (GCMs). We demonstrate that, for years not used for training, our lightning scheme captures &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;71.8&lt;/mn&gt;\u0000 &lt;mi&gt;%&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $71.8%$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; of the daily global spatio-temporal lightning variability, which corresponds to a &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;&gt;&lt;/mo&gt;\u0000 &lt;mn&gt;43&lt;/mn&gt;\u0000 &lt;mi&gt;%&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${ &gt;} 43%$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; relative improvement compared to well-established lightning schemes. Similarly, the scheme correlates well with lightning observations for the monthly climatology &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;mo&gt;&gt;&lt;/mo&gt;\u0000 &lt;mn&gt;0.92&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(r &gt; 0.92)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, inter-annual variability &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;mo&gt;&gt;&lt;/mo&gt;\u0000 &lt;mn&gt;0.76&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(r &gt; 0.76)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, and latitudinal and longitudinal distributions &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;mo&gt;&gt;&lt;/mo&gt;\u0000 &lt;mn&gt;0.87&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(r &gt; 0.87)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;. Most notably, the lightning scheme brings a critical improvement in representing lightning magnitude and variability in the thre","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 2","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004464","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Energetically Consistent Eddy-Diffusivity Mass-Flux Convective Schemes: 1. Theory and Models","authors":"M. Perrot,&nbsp;F. Lemarié,&nbsp;T. Dubos","doi":"10.1029/2024MS004273","DOIUrl":"https://doi.org/10.1029/2024MS004273","url":null,"abstract":"<p>This paper presents a self-contained derivation, from first principles, of a convective vertical mixing scheme based on the Eddy-Diffusivity Mass-Flux (EDMF) approach. This type of closure separates vertical turbulent fluxes into two components: an eddy-diffusivity (ED) which accounts for local small-scale mixing in a nearly isotropic environment, and a mass-flux (MF) transport term, which represents the non-local transport driven by vertically coherent plumes. Using the multi-fluid averaging underlying the MF concept, we review consistent energy budgets between resolved and subgrid scales for seawater and dry atmosphere, in anelastic and Boussinesq frameworks. We demonstrate that when using an EDMF scheme, closed energy budgets can be recovered if: (a) bulk production terms of turbulent kinetic energy (TKE) by shear buoyancy include MF contributions; (b) boundary conditions are consistent with EDMF, to avoid spurious energy fluxes at the boundary. Furthermore, we show that lateral mixing, due to either entrainment or detrainment induces a net production of TKE via the shear term, with enhanced production under increased horizontal drag. We also provide constraints on boundary conditions to ensure mathematical consistency. Throughout the theoretical development, we maintain transparency regarding underlying assumptions. In a companion paper (Perrot and Lemarié (2024, https://hal.science/hal-04666049); hereafter Part II) we assess the validity of these hypotheses, and analyze the sensitivity of the scheme to modeling choices against Large Eddy Simulations (LES) and observational data on oceanic convection. Part II also details an energy-conserving discretization and quantifies energy biases in inconsistent formulations.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004273","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143120154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Rapid Emulation of Spatially Resolved Temperature Response to Effective Radiative Forcing","authors":"Christopher B. Womack,&nbsp;Paolo Giani,&nbsp;Sebastian D. Eastham,&nbsp;Noelle E. Selin","doi":"10.1029/2024MS004523","DOIUrl":"https://doi.org/10.1029/2024MS004523","url":null,"abstract":"<p>Effective assessment of potential climate impacts requires the ability to rapidly predict the time-varying response of climate variables. This prediction must be able to consider different combinations of forcing agents at high resolution. Full-scale ESMs are too computationally intensive to run large scenario ensembles due to their long lead times and high costs. Faster approaches such as intermediate complexity modeling and pattern scaling are limited by low resolution and invariant response patterns, respectively. We propose a generalizable framework for emulating climate variables to overcome these issues, representing the climate system through spatially resolved impulse response functions. We derive impulse response functions by directly deconvolving effective radiative forcing and near-surface air temperature time series. This enables rapid emulation of new scenarios through convolution and derivation of other impulse response functions from any forcing to its response. We present results from an application to near-surface air temperature based on CMIP6 data. We evaluate emulator performance across 5 CMIP6 experiments including the SSPs, demonstrating accurate emulation of global mean and spatially resolved temperature change with respect to CMIP6 ensemble outputs. Global mean relative error in emulated temperature averages 1.49% in mid-century and 1.25% by end-of-century. These errors are likely driven by state-dependent climate feedbacks, such as the non-linear effects of Arctic sea ice melt. We additionally show an illustrative example of our emulator for policy evaluation and impact analysis, emulating spatially resolved temperature change for a 1,000 member scenario ensemble in less than a second.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004523","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143118657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Optimized Gross Primary Productivity Over the Croplands Within the BEPS Particle Filtering Data Assimilation System (BEPS_PF v1.0)","authors":"Xiuli Xing,&nbsp;Mousong Wu,&nbsp;Huajie Zhu,&nbsp;Wenzhuo Duan,&nbsp;Weimin Ju,&nbsp;Xiaorong Wang,&nbsp;Youhua Ran,&nbsp;Yongguang Zhang,&nbsp;Fei Jiang","doi":"10.1029/2024MS004412","DOIUrl":"https://doi.org/10.1029/2024MS004412","url":null,"abstract":"<p>Agricultural ecosystems play an important role in modulating the global carbon balance by taking up atmospheric carbon dioxide, while large differences and uncertainties exist in the estimated crop gross primary productivity (GPP) by terrestrial ecosystem models (TEMs). With the aim of reducing the parameter uncertainty in TEMs for crop GPP simulation, we developed a particle filtering data assimilation (DA) system based on the ecosystem model BEPS (Biosphere Exchange Process Simulator), that is, the BEPS_PF (v1.0). We investigated the feasibility of BEPS_PF on the multiple parameters optimization across typical crops (wheat, rice, soybean and corn) and on reducing the uncertainty of GPP over 32 cropland eddy covariance sites globally. With BEPS_PF DA, the average R² between GPP and observed data at the hourly scale has been efficiently improved by 0.36 and root mean square error reduced by 0.18 gC m⁻² hr⁻¹. The DA system has successfully corrected the GPP from the irrigated croplands which was severely underestimated by the model's prior parameters. We found that the maximum carboxylation rate at 25°C (<i>V</i>_cmax25) as well as the leaf nitrogen content (<i>N</i>_leaf) were co-varied with strong seasonal variations. The optimized <i>V</i>_cmax25 showed large differences among different crop types with ranges 27.07–62.95, 42.17–93.32, 31.89–105.81, and 38.34–89.29 μmol m⁻² s⁻¹ for corn, soybean, wheat, and rice respectively. We demonstrated that the BEPS_PF is an efficient tool for optimizing different processes in the ecosystems, and with the satellite data it can be extended to regional and global scales for more accurate estimation of carbon fluxes.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004412","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143117974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"A Novel Back-Calculation Approach to Estimate Ocean Anthropogenic Carbon Using Carbon-Based Data and a Total Matrix Intercomparison Method","authors":"M. López-Mozos,&nbsp;F. F. Pérez,&nbsp;L. I. Carracedo,&nbsp;G. Gebbie,&nbsp;A. Velo","doi":"10.1029/2024MS004330","DOIUrl":"https://doi.org/10.1029/2024MS004330","url":null,"abstract":"<p>Over the last decades, back-calculation (BC) techniques for ocean anthropogenic carbon (C_ant) estimation have improved and evolved into different methodologies that are not exempt from various assumptions and limitations. No single optimal BC method exists to date for computing C_ant; therefore, it is necessary to continue advancing the broad range of approaches. Here, we present a novel method based on the BC fundamentals that combines marine-carbonate-system (MCS) data and the Total Matrix Intercomparison (TMI) framework. This MCS-TMI approach differs from other BC methods by using the TMI to reconstruct deep-ocean biogeochemical properties and their preformed conditions. It also incorporates a global sea-air oxygen disequilibrium term, and a dynamic stoichiometric carbon-to-oxygen ratio that depends on the water-mass ideal time. The MCS-TMI yields a total C_ant inventory of 124 ± 7 Pg C (referred to 1995), in good agreement with previous global C_ant climatologies. The MCS-TMI method uncertainty (±5.6 μmol kg⁻¹) is controlled by input-data errors that, nonetheless, have a minimal impact on the total C_ant inventory. In contrast, our total C_ant inventory uncertainty is governed by methodological errors, specifically those related to the TMI's boundary conditions. Our study demonstrates the effectiveness of MCS data-based climatologies in reconstructing a 3D gridded C_ant climatology, and the validity of ocean circulation transport operators for obtaining BC preformed conditions.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004330","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143117726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Development and Application of a New Convective Entrainment Rate Parameterization for Improving Precipitation Simulation Over the Tibetan Plateau and Its Surrounding Areas","authors":"Junjun Li,&nbsp;Chunsong Lu,&nbsp;Jinghua Chen,&nbsp;Jian Li,&nbsp;Jing Yang,&nbsp;Xiaoqi Xu,&nbsp;Lei Zhu,&nbsp;Xin He,&nbsp;Shiying Wu","doi":"10.1029/2024MS004543","DOIUrl":"https://doi.org/10.1029/2024MS004543","url":null,"abstract":"<p>The Tibetan Plateau (TP) significantly impacts the global climate. TP's unique geographical conditions make it one of the areas with the largest precipitation biases in numerical models. The overestimation and distribution biases of precipitation in models are closely related to the parameterization of convection processes over the TP. In light of this, a new deep convective entrainment rate parameterization suitable for the region is developed based on convection observational data and is applied to the Grell-Freitas Ensemble Scheme of the Weather Research and Forecasting Model. The new scheme significantly reduces the overestimation of simulated precipitation over the TP, decreasing the overestimation from 29.4% in the default scheme to 11.8%. The physical mechanism behind the improved simulation results is as follows: first, the entrainment rate of convection in the new scheme is closer to the observed results. Second, in terms of cloud macrophysics, the new scheme increases the convective entrainment rate, reduces the cloud top height and depth of convective clouds, and decreases the number of grids with updrafts in the vertical layers and grids with convective precipitation on the surface. Third, in terms of cloud microphysics, the increased entrainment rate reduces the cloud water content and weakens the intensity of convective precipitation. All of these mechanisms ultimately reduce the accumulated convective precipitation amount, providing an optimized modeling tool for weather and climate research over TP, which also aids in better assessing the water cycle and water resource reserves of the “Asian Water Tower.”</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004543","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143116272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 Influence of Vertical Resolution on Internal Tide Energetics and Subsequent Effects on Underwater Acoustic Propagation","authors":"L. Hiron,&nbsp;M. C. Schönau,&nbsp;K. J. Raja,&nbsp;E. P. Chassignet,&nbsp;M. C. Buijsman,&nbsp;B. K. Arbic,&nbsp;A. Bozec,&nbsp;E. F. Coelho,&nbsp;M. S. Solano","doi":"10.1029/2024MS004389","DOIUrl":"https://doi.org/10.1029/2024MS004389","url":null,"abstract":"<p>Internal tide generation and breaking play a primary role in the vertical transport and mixing of heat and other properties in the ocean interior, thereby influencing climate regulation. Additionally, internal tides increase sound speed variability in the ocean, consequently impacting underwater acoustic propagation. With advancements in large-scale ocean modeling capabilities, it is essential to assess the impact of higher model resolutions (horizontal and vertical) in representing internal tides. This study investigates the influence of vertical resolution on internal tide energetics and its subsequent effects on underwater acoustic propagation in the HYbrid Coordinate Ocean Model (HYCOM). An idealized configuration with a ridge, forced only by semidiurnal tides and having 1-km horizontal grid-spacing, is used to test two different vertical-grid discretizations, defined based on the zero-crossings of horizontal velocity eigenfunctions and the merging of consecutive layers, with seven distinct numbers of isopycnal layers, ranging from 8 to 128. Analyses reveal that increasing the number of layers up to 48 increases barotropic-to-baroclinic tidal conversion, available potential energy, and vertical kinetic energy, converging with higher layer counts. Vertical shear exhibits a similar pattern but converges at 96 layers. Increasing the number of isopycnal layers, up to 48, increases the available potential energy contained in high (third-to-eighth) tidal baroclinic modes. Finally, sound speed variability and acoustic parameters differ for simulations with less than 48 layers. Therefore, the study concludes that a minimum vertical resolution (48 layers in this case) is required in isopycnal models to accurately represent internal tide properties and associated underwater acoustic propagation.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004389","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143115718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}