Journal of Advances in Modeling Earth Systems最新文献

{"title":"Interactive Stratospheric Aerosol Microphysics-Chemistry Simulations of the 1991 Pinatubo Volcanic Aerosols With Newly Coupled Sectional Aerosol and Stratosphere-Troposphere Chemistry Modules in the NASA GEOS Chemistry-Climate Model (CCM)","authors":"Parker Case,&nbsp;Peter R. Colarco,&nbsp;Brian Toon,&nbsp;Valentina Aquila,&nbsp;Christoph A. Keller","doi":"10.1029/2022MS003147","DOIUrl":"https://doi.org/10.1029/2022MS003147","url":null,"abstract":"<p>We have coupled the GEOS-Chem tropospheric-stratospheric chemistry mechanism and the Community Aerosol and Radiation Model for Atmospheres (CARMA), a sectional aerosol microphysics module, within the NASA Goddard Earth Observing System Chemistry-Climate Model (GEOS CCM) in order to simulate the interactions between stratospheric chemistry and aerosol microphysics. We use observations of the 1991 Mount Pinatubo volcanic cloud to evaluate this new version of the GEOS CCM. The GEOS-Chem chemistry module is used to simulate the oxidation of sulfur dioxide (SO₂) more realistically than assuming hydroxyl radical (OH) fields are constant, as OH concentrations in the plume decrease dramatically in the weeks following the eruption. CARMA simulates sulfate aerosols with dynamic microphysical and optical properties. The CARMA-calculated aerosol surface area is coupled to the chemistry module from GEOS-Chem for the calculation of heterogeneous chemistry. We use a set of observational and theoretical constraints for Pinatubo to evaluate the performance of this new version of the GEOS CCM. These simulations are specifically compared with satellite and in-situ observations and provide insights into the connections between the gas-phase chemistry and the aerosol microphysics of the early plume and how they impact the climatic and chemical changes following a large volcanic eruption. A second, smaller eruption is also included in these simulations, the 15 August 1991, eruption of Cerro Hudson in Chile, which we find essential in explaining the aerosol optical depth in the Southern Hemisphere in 1991.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 8","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2022MS003147","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6143694","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":"Toward Robust Parameterizations in Ecosystem-Level Photosynthesis Models","authors":"Shanning Bao,&nbsp;Lazaro Alonso,&nbsp;Siyuan Wang,&nbsp;Johannes Gensheimer,&nbsp;Ranit De,&nbsp;Nuno Carvalhais","doi":"10.1029/2022MS003464","DOIUrl":"https://doi.org/10.1029/2022MS003464","url":null,"abstract":"<p>In a model simulating dynamics of a system, parameters can represent system sensitivities and unresolved processes, therefore affecting model accuracy and uncertainty. Taking a light use efficiency (LUE) model as an example, which is a typical approach for estimating gross primary productivity (GPP), we propose a Simultaneous Parameter Inversion and Extrapolation approach (SPIE) to overcome issues stemming from plant-functional-type (PFT)-dependent parameterizations. SPIE refers to predicting model parameters using an artificial neural network based on collected variables, including PFT, climate types, bioclimatic variables, vegetation features, atmospheric nitrogen and phosphorus deposition, and soil properties. The neural network was optimized to minimize GPP errors and constrain LUE model sensitivity functions. We compared SPIE with 11 typical parameter extrapolating methods, including PFT- and climate-specific parameterizations, global and PFT-based parameter optimization, site-similarity, and regression approaches. All methods were assessed using Nash-Sutcliffe model efficiency (NSE), determination coefficient and normalized root mean squared error, and contrasted with site-specific calibrations. Ten-fold cross-validated results showed that SPIE had the best performance across sites, various temporal scales and assessing metrics. Taking site-level calibrations as a benchmark (NSE = 0.95), SPIE performed with an NSE of 0.68, while all the other investigated approaches showed negative NSE. The Shapley value, layer-wise relevance and partial dependence showed that vegetation features, bioclimatic variables, soil properties and some PFTs determine parameters. SPIE overcomes strong limitations observed in many standard parameterization methods. We argue that expanding SPIE to other models overcomes current limits and serves as an entry point to investigate the robustness and generalization of different models.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 8","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2022MS003464","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6098628","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":"Scale-Dependent Estimability of Turbulent Flux in the Unstable Surface Layer for Land Surface Modeling","authors":"Shaofeng Liu,&nbsp;Xubin Zeng,&nbsp;Yongjiu Dai,&nbsp;Hua Yuan,&nbsp;Nan Wei,&nbsp;Zhongwang Wei,&nbsp;Xingjie Lu,&nbsp;Shupeng Zhang,&nbsp;Xian-Xiang Li","doi":"10.1029/2022MS003567","DOIUrl":"https://doi.org/10.1029/2022MS003567","url":null,"abstract":"<p>Surface flux estimation is essential to land surface modeling in earth system models. In practice, parameterizations of surface turbulent fluxes are almost all based on the similarity theory. That is, the grid or subgrid mean surface-layer flow is assumed at equilibrium with the underlying earth surface, and therefore some empirical relations can be used to estimate surface fluxes. In this paper, scale-dependent estimability of turbulent flux in the unstable surface layer is systematically investigated based on high-resolution large-eddy simulation data over a flat and homogeneous domain, representing a typical land surface modeling grid. It is found that turbulent flow in the unstable surface layer inherently fluctuates over a wide range of scales. This kind of fluctuation affects the steady-state relations between mean atmospheric quantities and underlying earth surface, and hence affects the estimability of surface fluxes. Sensitivity tests show that the relative root mean square error of the estimated surface friction velocity for a subdomain generally increases as the subdomain becomes smaller. The error can be as high as 35% as the subdomain size decreases to the order of the surface layer height. To achieve an error of 10% for all cases, the subdomain size should be at least on the order of the boundary layer height. These findings imply that estimability-based strategies may be needed for representing subgrid heterogeneity for surface flux estimation in land surface modeling.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 8","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2022MS003567","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6143693","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":"Ensemble Spread Behavior in Coupled Climate Models: Insights From the Energy Exascale Earth System Model Version 1 Large Ensemble","authors":"Samantha Stevenson,&nbsp;Xingying Huang,&nbsp;Yingying Zhao,&nbsp;Emanuele Di Lorenzo,&nbsp;Matthew Newman,&nbsp;Luke van Roekel,&nbsp;Tongtong Xu,&nbsp;Antonietta Capotondi","doi":"10.1029/2023MS003653","DOIUrl":"https://doi.org/10.1029/2023MS003653","url":null,"abstract":"<p>Assessing uncertainty in future climate projections requires understanding both internal climate variability and external forcing. For this reason, single-model initial condition large ensembles (SMILEs) run with Earth System Models (ESMs) have recently become popular. Here we present a new 20-member SMILE with the Energy Exascale Earth System Model version 1 (E3SMv1-LE), which uses a “macro” initialization strategy choosing coupled atmosphere/ocean states based on inter-basin contrasts in ocean heat content (OHC). The E3SMv1-LE simulates tropical climate variability well, albeit with a muted warming trend over the twentieth century due to overly strong aerosol forcing. The E3SMv1-LE's initial climate spread is comparable to other (larger) SMILEs, suggesting that maximizing inter-basin ocean heat contrasts may be an efficient method of generating ensemble spread. We also compare different ensemble spread across multiple SMILEs, using surface air temperature and OHC. The Community Earth system Model version 1, the only ensemble which utilizes a “micro” initialization approach perturbing only atmospheric initial conditions, yields lower spread in the first ∼30 years. The E3SMv1-LE exhibits a relatively large spread, with some evidence for anthropogenic forcing influencing spread in the late twentieth century. However, systematic effects of differing “macro” initialization strategies are difficult to detect, possibly resulting from differing model physics or responses to external forcing. Notably, the method of standardizing results affects ensemble spread: control simulations for most models have either large background trends or multi-centennial variability in OHC. This spurious disequlibrium behavior is a substantial roadblock to understanding both internal climate variability and its response to forcing.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003653","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5789646","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":"Efficient Super-Resolution of Near-Surface Climate Modeling Using the Fourier Neural Operator","authors":"Peishi Jiang,&nbsp;Zhao Yang,&nbsp;Jiali Wang,&nbsp;Chenfu Huang,&nbsp;Pengfei Xue,&nbsp;T. C. Chakraborty,&nbsp;Xingyuan Chen,&nbsp;Yun Qian","doi":"10.1029/2023MS003800","DOIUrl":"https://doi.org/10.1029/2023MS003800","url":null,"abstract":"<p>Downscaling methods are critical in efficiently generating high-resolution atmospheric data. However, state-of-the-art statistical or dynamical downscaling techniques either suffer from the high computational cost of running a physical model or require high-resolution data to develop a downscaling tool. Here, we demonstrate a recently proposed <i>zero-shot super-resolution</i> method, the Fourier neural operator (FNO), to efficiently perform downscaling without the need for high-resolution data. Because the FNO learns dynamics in Fourier space, FNO is a resolution-invariant emulator; it can be trained at a coarse resolution and produces emulation at any high resolution. We applied FNO to downscale a 4-km resolution Weather Research and Forecasting (WRF) Model simulation of near-surface heat-related variables over the Great Lakes region. The FNO is driven by the atmospheric forcings and topographic features used in the WRF model at the same resolution. We incorporated a physics-constrained loss in FNO by using the Clausius–Clapeyron relation to better constrain the relations among the emulated states. Trained on merely 600 WRF snapshots at 4-km resolution, the FNO shows comparable performance with a widely-used convolutional network, U-Net, achieving averaged <i>modified Kling–Gupta Efficiency</i> of 0.88 and 0.94 on the test data set for temperature and pressure, respectively. We then employed the FNO to produce 1-km emulations to reproduce the fine climate features. Further, by taking the WRF simulation as ground truth, we show consistent performances at the two resolutions, suggesting the reliability of FNO in producing high-resolution dynamics. Our study demonstrates the potential of using FNO for zero-shot super-resolution in generating first-order estimation on atmospheric modeling.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003800","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5653011","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 Functionalized Monte Carlo 3D Radiative Transfer Model: Radiative Effects of Clouds Over Reflecting Surfaces","authors":"Najda Villefranque,&nbsp;Howard W. Barker,&nbsp;Jason N. S. Cole,&nbsp;Zhipeng Qu","doi":"10.1029/2023MS003674","DOIUrl":"https://doi.org/10.1029/2023MS003674","url":null,"abstract":"<p>In the Earth Sciences, the 3D radiative transfer equation is often solved for by Monte Carlo (MC) methods. They can, however, be computationally taxing, and that can narrow their range of application and limit their use in explorations of model parameter spaces. A novel family of MC algorithms is investigated here in which single simulations provide estimates of both radiative quantities A for a set of parameters , as usual, as well as the overarching functional (<i>x</i>) that can be evaluated, extremely efficiently, at any <i>x</i>. One such algorithm is developed and demonstrated for horizontally averaged broadband solar radiative fluxes as functions of surface albedo for uniform Lambertian surfaces beneath inhomogeneous cloudy atmospheres. Simulations for a high-resolution synthetic cloud field, at various solar zenith angles, illustrate the potential of the method to gain insights into the nature of 3D radiative effects for complicated atmosphere-surface conditions using information specially derived from the MC simulation. For simulations performed with a single surface albedo it is found that as surface albedo increases, 3D radiative effects increase, too, with maxima occurring at middling to large values, and then decrease. By utilizing the derived coefficients that describe it was established that these 3D effects stem from differences in fractions of radiation entrapped at successive orders of internal multiple reflections for 1D and 3D transfer.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003674","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5745734","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":"Insights on Simulating Summer Warming of the Great Lakes: Understanding the Behavior of a Newly Developed Coupled Lake-Atmosphere Modeling System","authors":"Miraj B. Kayastha,&nbsp;Chenfu Huang,&nbsp;Jiali Wang,&nbsp;William J. Pringle,&nbsp;TC Chakraborty,&nbsp;Zhao Yang,&nbsp;Robert D. Hetland,&nbsp;Yun Qian,&nbsp;Pengfei Xue","doi":"10.1029/2023MS003620","DOIUrl":"https://doi.org/10.1029/2023MS003620","url":null,"abstract":"<p>The Laurentian Great Lakes are the world's largest freshwater system and regulate the climate of the Great Lakes region, which has been increasingly experiencing climatic, hydrological, and ecological changes. An accurate mechanistic representation of the Great Lakes thermal structure in Regional Climate Models (RCMs) is paramount to studying the climate of this region. Currently, RCMs have primarily represented the Great Lakes through coupled one-dimensional (1D) column lake models; this approach works well for small inland lakes but is unable to resolve the realistic hydrodynamics of the Great Lakes and leads to inaccurate representations of lake surface temperature (LST) that influence regional climate and weather patterns. This work overcomes this limitation by developing a fully two-way coupled modeling system using the Weather Research and Forecasting model and a three-dimensional (3D) hydrodynamic model. The coupled model system resolves the interactive physical processes between the atmosphere, lake, and surrounding watersheds; and validated against a range of observational data. The model is then used to investigate the potential impacts of lake-atmosphere coupling on the simulated summer LST of Lake Superior. By evaluating the difference between our two-way coupled modeling system and our observation-driven modeling system, we find that coupled-lake atmosphere dynamics can lead to a higher LST during June-September through higher net surface heat flux entering the lake in June and July and a lower net surface heat flux entering the lake in August and September. The unstratified water in June distributes the entering surface heat flux throughout the water column leading to a minor LST increase, while the stratified waters of July create a conducive thermal structure for the water surface to warm rapidly under the higher incoming surface heat flux. This research provides insight into the coupled modeling system behavior, which is critical for enhancing our predictive understanding of the Great Lakes climate system.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003620","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6184070","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":"How Well do We Understand the Planck Feedback?","authors":"Timothy W. Cronin,&nbsp;Ishir Dutta","doi":"10.1029/2023MS003729","DOIUrl":"https://doi.org/10.1029/2023MS003729","url":null,"abstract":"<p>A reference or “no-feedback” radiative response to warming is fundamental to understanding how much global warming will occur for a given change in greenhouse gases or solar radiation incident on the Earth. The simplest estimate of this radiative response is given by the Stefan-Boltzmann law as  W m⁻² K⁻¹ for Earth's present climate, where is a global effective emission temperature. The comparable radiative response in climate models, widely called the “Planck feedback,” averages −3.3 W m⁻² K⁻¹. This difference of 0.5 W m⁻² K⁻¹ is large compared to the uncertainty in the net climate feedback, yet it has not been studied carefully. We use radiative transfer models to analyze these two radiative feedbacks to warming, and find that the difference arises primarily from the lack of stratospheric warming assumed in calculations of the Planck feedback (traditionally justified by differing constraints on and time scales of stratospheric adjustment relative to surface and tropospheric warming). The Planck feedback is thus masked for wavelengths with non-negligible stratospheric opacity, and this effect implicitly acts to amplify warming in current feedback analysis of climate change. Other differences between Planck and Stefan-Boltzmann feedbacks arise from temperature-dependent gas opacities, and several artifacts of nonlinear averaging across wavelengths, heights, and different locations; these effects partly cancel but as a whole slightly destabilize the Planck feedback. Our results point to an important role played by stratospheric opacity in Earth's climate sensitivity, and clarify a long-overlooked but notable gap in our understanding of Earth's reference radiative response to warming.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023MS003729","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5896146","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":"Climate Model Code Genealogy and Its Relation to Climate Feedbacks and Sensitivity","authors":"Peter Kuma,&nbsp;Frida A.-M. Bender,&nbsp;Aiden R. J?nsson","doi":"10.1029/2022MS003588","DOIUrl":"https://doi.org/10.1029/2022MS003588","url":null,"abstract":"<p>Contemporary general circulation models (GCMs) and Earth system models (ESMs) are developed by a large number of modeling groups globally. They use a wide range of representations of physical processes, allowing for structural (code) uncertainty to be partially quantified with multi-model ensembles (MMEs). Many models in the MMEs of the Coupled Model Intercomparison Project (CMIP) have a common development history due to sharing of code and schemes. This makes their projections statistically dependent and introduces biases in MME statistics. Previous research has focused on model output and code dependence, and model code genealogy of CMIP models has not been fully analyzed. We present a full reconstruction of CMIP3, CMIP5, and CMIP6 code genealogy of 167 atmospheric models, GCMs, and ESMs (of which 114 participated in CMIP) based on the available literature, with a focus on the atmospheric component and atmospheric physics. We identify 12 main model families. We propose family and ancestry weighting methods designed to reduce the effect of model structural dependence in MMEs. We analyze weighted effective climate sensitivity (ECS), climate feedbacks, forcing, and global mean near-surface air temperature, and how they differ by model family. Models in the same family often have similar climate properties. We show that weighting can partially reconcile differences in ECS and cloud feedbacks between CMIP5 and CMIP6. The results can help in understanding structural dependence between CMIP models, and the proposed ancestry and family weighting methods can be used in MME assessments to ameliorate model structural sampling biases.</p>","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2022MS003588","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6104656","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":"Novel Geometric Parameters for Assessing Flow Over Realistic Versus Idealized Urban Arrays","authors":"Jiachen Lu,&nbsp;Negin Nazarian,&nbsp;Melissa Anne Hart,&nbsp;E. Scott Krayenhoff,&nbsp;Alberto Martilli","doi":"10.1029/2022MS003287","DOIUrl":"https://doi.org/10.1029/2022MS003287","url":null,"abstract":"Urban heterogeneity, such as the variation of street layouts, building shapes, and building heights, cannot be fully represented by density parameters commonly used in idealized urban environmental analyses. To address this shortcoming and better model flow fields over complex urban neighborhoods, we propose two novel descriptive geometric parameters, alignedness and building facet entropy, which quantify the connectivity of inter‐building spaces along the prevailing wind direction and the variation of building facet orientations, respectively. We then conducted large eddy simulations over 101 urban layouts, including realistic urban configurations with uniform building height as well as idealized building arrays with variable heights, and evaluated the resulting bulk flow properties. Urban canopy flow over realistic neighborhoods resembles staggered building arrays for low urban densities but becomes similar to aligned configurations beyond λp ∼ 0.25 where the realistic flow is less sensitive to changes in density. We further show that compared to traditional density parameters (such as plan and frontal area densities), the mean alignedness, a measure of connectivity of flow paths in street canyons, better predicts canopy‐averaged flow properties. Furthermore, for realistic urban flow, the dispersive momentum flux shows a clear increasing trend with building density, and a decreasing trend with alignedness, which is in contrast with idealized cases that exhibit no clear trend. This distinct behavior further highlights the necessity of evaluating flow over realistic urban layouts for flow parameterization. This study provides an improved method of describing urban layouts for flow characterization that can be applied in neighborhood‐scale urban canopy parameterization.","PeriodicalId":14881,"journal":{"name":"Journal of Advances in Modeling Earth Systems","volume":"15 7","pages":""},"PeriodicalIF":6.8,"publicationDate":"2023-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2022MS003287","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6091652","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}