Journal of Advances in Modeling Earth Systems最新文献

{"title":"Modeling Thermal and Biogeochemical Dynamics in Two Ponds Within Alaska's Yukon–Kuskokwim Delta: Impacts of Climatic Variability on Greenhouse Gas Fluxes","authors":"A. L. Mullen,&nbsp;E. E. Jafarov,&nbsp;J. K. Y. Hung,&nbsp;K. Gurbanov,&nbsp;V. Stepanenko,&nbsp;B. M. Rogers,&nbsp;J. D. Watts,&nbsp;S. M. Natali,&nbsp;B. A. Poulin","doi":"10.1029/2024MS004441","DOIUrl":"https://doi.org/10.1029/2024MS004441","url":null,"abstract":"<p>Fluxes of carbon dioxide (CO₂) and methane (CH₄) from open water bodies are critical components of carbon-climate feedbacks in high latitudes. Processes governing the spatial and temporal variability of these aquatic greenhouse gas (GHG) fluxes are still highly uncertain due to limited observational data sets and lack of modeling studies incorporating comprehensive thermal and biochemical processes. This research investigates how slight variations in climate propagate through the biogeochemical cycles of ponds and resulting impacts on GHG emissions. We examine the thermal and biogeochemical dynamics of two ponds in the Yukon–Kuskokwim Delta, Alaska, under varying climatic conditions to study the impacts on CO₂, CH₄, and oxygen (O₂) concentrations and fluxes. We performed multiple numerical experiments, using the LAKE process-based model and field measurements, to analyze how these ponds respond to variations in air temperature, shortwave radiation, and snow cover. Our study demonstrates that ice cover duration and water temperature are primary climatic drivers of GHG fluxes. Climate experiments led to reductions in ice cover duration and increased water temperatures, which subsequently enhanced CH₄ and CO₂ gas emissions from two study ponds. On average, cumulative CH₄ and CO₂ emissions were 5% and 10% higher, respectively, under increases in air temperature and shortwave radiation. Additionally, we uncovered a need to incorporate groundwater influxes of dissolved gases and nutrients in order to fully represent processes governing aquatic biochemical activity. Our work highlights the importance of understanding local-scale processes in predicting future Arctic contributions to GHG emissions.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004441","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865681","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 Unified Framework to Reconcile Different Approaches of Modeling Transpiration Response to Water Stress: Plant Hydraulics, Supply Demand Balance, and Empirical Soil Water Stress Function","authors":"Yi Yang,&nbsp;Kaiyu Guan,&nbsp;Bin Peng,&nbsp;Xue Feng,&nbsp;Xiangtao Xu,&nbsp;Ming Pan,&nbsp;Brandon P. Sloan,&nbsp;Jingwen Zhang,&nbsp;Wang Zhou,&nbsp;Lingcheng Li,&nbsp;Murugesu Sivapalan,&nbsp;Elizabeth A. Ainsworth,&nbsp;Kimberly A. Novick,&nbsp;Zong-Liang Yang,&nbsp;Sheng Wang","doi":"10.1029/2023MS003911","DOIUrl":"https://doi.org/10.1029/2023MS003911","url":null,"abstract":"<p>Plant responses to water stress is a major uncertainty to predicting terrestrial ecosystem sensitivity to drought. Different approaches have been developed to represent plant water stress. Empirical approaches (the empirical soil water stress (or Beta) function and the supply-demand balance scheme) have been widely used for many decades; more mechanistic based approaches, that is, plant hydraulic models (PHMs), were increasingly adopted in the past decade. However, the relationships between them—and their underlying connections to physical processes—are not sufficiently understood. This limited understanding hinders informed decisions on the necessary complexities needed for different applications, with empirical approaches being mechanistically insufficient, and PHMs often being too complex to constrain. Here we introduce a unified framework for modeling transpiration responses to water stress, within which we demonstrate that empirical approaches are special cases of the full PHM, when the plant hydraulic parameters satisfy certain conditions. We further evaluate their response differences and identify the associated physical processes. Finally, we propose a methodology for assessing the necessity of added complexities of the PHM under various climatic conditions and ecosystem types, with case studies in three typical ecosystems: a humid Midwestern cropland, a semi-arid evergreen needleleaf forest, and an arid grassland. Notably, Beta function overestimates transpiration when VPD is high due to its lack of constraints from hydraulic transport and is therefore insufficient in high VPD environments. With the unified framework, we envision researchers can better understand the mechanistic bases of and the relationships between different approaches and make more informed choices.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003911","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865849","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":"Langmuir Mixing Schemes Based on a Modified K-Profile Parameterization","authors":"Peng Wang,&nbsp;James C. McWilliams,&nbsp;Jianguo Yuan,&nbsp;Jun-Hong Liang","doi":"10.1029/2024MS004729","DOIUrl":"https://doi.org/10.1029/2024MS004729","url":null,"abstract":"<p>Langmuir turbulence, a dominant process in the ocean surface boundary layer, drives substantial vertical mixing that influences temperature, salinity, mixed layer depth, and biogeochemical tracer distributions. While direct resolution of Langmuir turbulence in ocean and climate models remains computationally prohibitive, its effects are commonly parameterized, frequently within established turbulent mixing frameworks like the K-profile parameterization (KPP). This study utilizes a modified KPP that determines boundary layer depth through an integral criterion, diverging from the conventional KPP's dependence on the bulk Richardson number. The modified KPP demonstrates markedly lower sensitivity to model vertical resolution than its conventional counterpart. Building upon this modified KPP framework, we introduce an innovative parameterization scheme for Langmuir mixing effects. We evaluate the performance of this new scheme against existing approaches using a one-dimensional (1D) column model across four different scenarios, incorporating validation against both large eddy simulation (LES) results and field measurements. Our analysis reveals that the new Langmuir mixing scheme, explicitly designed for the modified KPP framework, performs competitively while maintaining reduced sensitivity to vertical resolution.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004729","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143866020","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":"Whole-Profile Soil Carbon Responses to Climate Change Modulated by Vertical Carbon Transport and Priming Effect Gradients","authors":"Mingming Wang,&nbsp;Shuai Zhang,&nbsp;Lingzao Zeng,&nbsp;Zhongkui Luo","doi":"10.1029/2024MS004670","DOIUrl":"https://doi.org/10.1029/2024MS004670","url":null,"abstract":"<p>The vertical transport (VT) of soil organic carbon (SOC) mixes carbon pools of varying depth-origin and decomposability, regulating whole-profile SOC dynamics through altered carbon pool interactions, such as the priming effect (PE). However, quantifying this process in situ is challenging. Using global data sets on SOC stocks and carbon inputs, we trained a depth-resolved SOC model incorporating VT and PE to assess the vertical gradient of VT and PE, and explore their roles in regulating whole-profile SOC dynamics in response to climate change. The results indicate that VT-induced redistribution of SOC is essential for capturing observed profile distribution of SOC stocks. Transported carbon from neighboring layers accounted for 8%–27% of total layer-specific carbon inputs, varying by depth and ecosystem type, and regulated SOC turnover behavior via the PE, especially in deeper layers. Precipitation emerged as the most important factor influencing layer-specific VT. While the PE was higher in upper layers, it was far from its maximum potential in deeper layers, making SOC dynamics in these layers more sensitive to carbon input changes. If VT and PE gradients are not considered, the sensitivity of whole-profile SOC to warming will be underestimated, and the impact of carbon input changes will be overestimated, particularly in deeper layers. Our findings highlight the critical role of VT and PE in controlling whole-profile SOC dynamics, underscoring the need to explicitly include these processes in Earth system models for reliable whole-profile SOC predictions under climate change.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004670","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856824","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":"Implementation of Sub-Grid Scale Temperature Perturbations Induced by Non-Orographic Gravity Waves in WACCM6","authors":"Simchan Yook,&nbsp;Susan Solomon,&nbsp;Michael Weimer,&nbsp;Douglas E. Kinnison,&nbsp;Rolando Garcia,&nbsp;Kane Stone","doi":"10.1029/2024MS004625","DOIUrl":"https://doi.org/10.1029/2024MS004625","url":null,"abstract":"<p>Atmospheric gravity waves can play a significant role on atmospheric chemistry through temperature fluctuations. A recent modeling study introduced a method to implement subgrid-scale <i>orographic</i> gravity-wave-induced temperature perturbations in the Whole Atmosphere Community Climate Model (WACCM). The model with a wave-induced temperature parameterization was able to reproduce for example, the influence of mountain wave events on atmospheric chemistry, as highlighted in previous literature. Here we extend the subgrid-scale wave-induced temperature parameterization to also include <i>non-orographic</i> gravity waves arising from frontal activity and convection. We explore the impact of these waves on middle atmosphere chemistry, particularly focusing on reactions that are strongly sensitive to temperature. The non-orographic gravity waves increase the variability of chemical reaction rates, especially in the lower mesosphere. As an example, we show that this, in turn, leads to increases in the daytime ozone variability. To demonstrate another impact, we briefly investigate the role of non-orographic gravity waves in cirrus cloud formation in this model. Consistent with findings from the previous study focusing on orographic gravity waves, non-orographic waves also enhance homogeneous nucleation and increase cirrus clouds. The updated method used enables the global chemistry-climate model to account for both orographic and non-orographic gravity-wave-induced subgrid-scale dynamical perturbations in a consistent manner.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004625","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853016","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 Two-Dimensional Model for Eddy Saturation and Frictional Control in the Southern Ocean","authors":"J. R. Maddison,&nbsp;D. P. Marshall,&nbsp;J. Mak,&nbsp;K. Maurer-Song","doi":"10.1029/2024MS004682","DOIUrl":"https://doi.org/10.1029/2024MS004682","url":null,"abstract":"<p>The reduced sensitivity of mean Southern Ocean zonal transport with respect to surface wind stress magnitude changes, known as eddy saturation, is studied in an idealized analytical model. The model is based on the assumption of a balance between surface wind stress forcing and bottom dissipation in the planetary geostrophic limit, coupled to the GEOMETRIC form of the Gent–McWilliams eddy parameterization. The assumption of a linear stratification, together with an equation for the parameterized domain integrated total eddy energy, enables the formulation of a two component dynamical system, which reduces to the non-linear oscillator of Ambaum and Novak (2014, https://doi.org/10.1002/qj.2352) in a Hamiltonian limit. The model suggests an intrinsic oscillatory time scale for the Southern Ocean, associated with a combination of mean shear erosion by eddies and eddy energy generation by the mean shear. For Southern Ocean parameters the model suggests that perturbing the system via stochastic wind forcing may lead to relatively large excursions in eddy energy.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004682","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853017","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":"Future Trends of Global Agricultural Emissions of Ammonia in a Changing Climate","authors":"M. Beaudor,&nbsp;N. Vuichard,&nbsp;J. Lathière,&nbsp;D. A. Hauglustaine","doi":"10.1029/2023MS004186","DOIUrl":"https://doi.org/10.1029/2023MS004186","url":null,"abstract":"&lt;p&gt;Because of human population growth and changes in diet, global livestock and associated ammonia &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mfenced&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;H&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mfenced&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $left(mathrm{N}{mathrm{H}}_{mathrm{3}}right)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, emissions are projected to increase through the end of the century, with possible impacts on atmospheric chemistry and climate. In this study, we propose a methodology to project global gridded livestock densities and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;H&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $mathrm{N}{mathrm{H}}_{mathrm{3}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; emissions from agriculture until 2100. Based on a downscaling method, future livestock distribution has been estimated until 2100 for three Shared Socio-economic Pathways (SSP2-4.5, SSP4-3.4, and SSP5-8.5) and used in a global process-based model (Calculation of AMmonia Emissions in ORCHIDEE, CAMEO) to estimate agricultural ammonia emissions during the 21st century. Emissions under SSP4-3.4 and SSP5-8.5 calculated by CAMEO compare well with the range estimated by the Integrated Assessment Models (IAM; 50 to 66 &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;mi&gt;g&lt;/mi&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;mo&gt;.&lt;/mo&gt;\u0000 &lt;mi&gt;y&lt;/mi&gt;\u0000 &lt;msup&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $mathrm{T}mathrm{g}mathrm{N}.mathrm{y}{mathrm{r}}^{-mathrm{1}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) in the framework of the Phase 6 of the Coupled Model Intercomparison Project (CMIP6). Some opposite trends arise under SSP2.4-5 where CAMEO emissions increase consistently in response to the increasing trends in synthetic fertilizer use under this scenario. Africa is identified as the most emitting region worldwide, with &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;H&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $mathrm{N}{ma","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS004186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852657","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":"Exploring Baroclinic Instability of the Computational Kind (BICK) in Numerical Simulations of the Ocean","authors":"Claire Ménesguen,&nbsp;Nicolas Ducousso,&nbsp;Clément Vic,&nbsp;Sylvie Le Gentil","doi":"10.1029/2024MS004600","DOIUrl":"https://doi.org/10.1029/2024MS004600","url":null,"abstract":"&lt;p&gt;Primitive-equation models are essential tools for studying ocean dynamics and their ever-increasing resolution uncovers ever finer scales. At mesoscales and submesoscales, baroclinic instability is one of the main drivers of turbulence, but spurious numerical instabilities can also arise, leading to nonphysical dynamics. This study investigates a spurious instability termed Baroclinic Instability of Computational Kind (BICK), discovered in Arakawa and Moorthi (1988, https://doi.org/10.1175/1520-0469(1988)045&lt;1688:BIIVDS&gt;2.0.CO;2) and Bell and White (2017, https://doi.org/10.1016/j.ocemod.2017.08.001), through idealized configurations using a vertical (Modified) Lorenz grid. Here, we explore the growth of BICK within quasi-geostrophic (QG) and hydrostatic primitive-equation (HPE) frameworks for different setups: the canonical Eady configuration, stratification-modified Eady configurations, and a surface-intensified jet configuration. Our results confirm that the emergence of BICK is specific to the vertical staggering of the (Modified) Lorenz grids. Its growth is consistent with linear QG theory, and BICK is confined near the surface and bottom boundaries. In HPE simulations, the nonlinear evolution of BICK generates small-scale spurious eddies and reduces frontal sharpness. Increasing the number of levels reduces BICK's horizontal scale down to below the model's effective resolution. We illustrate this property using regional HPE simulations with a varying number of levels. BICK is found to significantly affect the vertically under-resolved simulations by introducing small-scale noise from both the bottom and surface boundaries. Our recommendation is to keep the ratio between the model horizontal &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;δ&lt;/mi&gt;\u0000 &lt;mi&gt;x&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(delta x)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and vertical &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;δ&lt;/mi&gt;\u0000 &lt;mi&gt;z&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(delta z)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; resolution greater than &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;mi&gt;f&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $2N/f$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, where &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004600","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853014","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":"Neural Data Assimilation for Regime Shift Monitoring of an Idealized AMOC Chaotic Model","authors":"Perrine Bauchot,&nbsp;Angélique Drémeau,&nbsp;Florian Sévellec,&nbsp;Ronan Fablet","doi":"10.1029/2024MS004462","DOIUrl":"https://doi.org/10.1029/2024MS004462","url":null,"abstract":"<p>Data assimilation (DA) reconstructs and forecasts the dynamics of geophysical processes using available observations and physical a priori. Recently, the hybridization of DA and deep learning has opened new perspectives to address model-data interactions. This paper explores its potential contribution to the analysis of a chaotic oceanic phenomenon: the centennial to millennial variability of the North Atlantic ocean circulation during the last glacial period. The implemented neural approach—4DVarNet—yields meaningful improvements over a classical variational DA method in reconstructing regime shifts of the Atlantic Meridional Overturning Circulation (AMOC), especially when fewer observations are available. Interestingly, results exhibit that exploiting explicitly the a priori dynamical model does not lead to better performances compared to a data-driven model. Additionally, we compare four sampling strategies to assess how observation patterns influence the capture of unstable AMOC phases. We highlight the gain of regular over random sampling strategies, with reconstruction errors dropping below 2% for a 100-year sampling period. We find that monitoring the AMOC with regular clusters of three consecutive observation points can reduce errors by a factor of five. Eventually, we assess 4DVarNet's robustness in reconstructing a partially-observed system and in generalizing to different dynamical regimes. We also investigate on the maximum sampling periods that 4DVarNet can assimilate without compromising reconstruction quality. This study, based on an idealized yet complex physical model, suggests that neural approaches trained on observations wisely acquired could improve the monitoring of regime shifts in the context of climate change.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853018","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":"Intensity Oscillations of Tropical Cyclones: Surface Versus Mid and Upper Tropospheric Processes","authors":"Andrea Polesello,&nbsp;Giousef Alexandros Charinti,&nbsp;Agostino Niyonkuru Meroni,&nbsp;Caroline Jane Muller,&nbsp;Claudia Pasquero","doi":"10.1029/2024MS004613","DOIUrl":"https://doi.org/10.1029/2024MS004613","url":null,"abstract":"<p>Some of the classical models of tropical cyclone intensification predict tropical cyclones to intensify up to a steady intensity, which depends on surface fluxes only, without any relevant role played by convective motions in the troposphere, typically assumed to have a moist adiabatic lapse rate. Simulations performed using the non-hydrostatic, high-resolution model System for Atmosphere Modeling in idealized settings (rotating radiative-convective equilibrium on a doubly periodic domain) show early intensification consistent with these theoretical expectations, but different intensity evolution, with the cyclone undergoing an oscillation in wind speed. This oscillation can be linked to feedbacks between the cyclone intensity and air buoyancy: convective heating, radiative heating, and mixing with warm low stratospheric air warm the mid and upper troposphere of the cyclone stabilizing the air column and thus reducing its intensity. After the intensity decay phase, mid and upper tropospheric cooling, mostly through cold advection from the surroundings, cooled by radiation, rebuilds Convective Available Potential Energy, that peaks just before a new intensification phase. These idealized simulations thus highlight the potentially important interactions between a tropical cyclone, its environment and radiation.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"17 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024MS004613","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852658","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}