Dynamics of Atmospheres and Oceans最新文献

Application of Weibull distribution and stable energy concept for numerical solutions of random wave heights

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-20 DOI: 10.1016/j.dynatmoce.2025.101544

Nga Thanh Duong , Loc Xuan Luu , Linh Hoang Tran , Khiem Quang Tran

This study focuses on developing a new energy dissipation model and a corresponding solution for random wave height transformation based on stable energy theory and the Weibull distribution. Eight previously established breaking wave height formulas will be evaluated for compatibility with the new numerical solution in predicting wave height. A range of evaluation criteria (e.g., relative root-mean-square error (RRMSE), root-mean-square error (RMSE), mean absolute error (MAE), and standard deviation (ν)) will be applied to verify the reliability of the developed energy dissipation model alongside 13 existing models, using a large dataset of up to 6007 data points collected from 11 historical experiments. The results indicate that the NK1 solution for wave height transformation derived from the new energy dissipation model DB1 performs best in wave height prediction, with optimal shape and scale parameters of 1.53 and 0.83, respectively. The use of the DB1 model (or, equivalently, the NK1 solution) reduces errors compared to the 13 existing models by 8.1–69.4 % for RRMSE. For other evaluation criteria, DB1 also consistently outperforms the existing models. The findings further suggest that the stable energy concept is a feasible approach despite receiving limited attention from researchers. Additionally, the Weibull distribution is recommended for developing energy dissipation models or solutions for irregular wave height transformation. Therefore, the newly developed DB1 model and corresponding NK1 solution are strongly recommended for calculating random wave height transformation.

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引用次数: 0

Enhancing coastal wind simulation in the WRF model: Updates in sea surface temperature and roughness length through dynamic boundary conditions

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-17 DOI: 10.1016/j.dynatmoce.2025.101542

Chunlei Wu , Nina Wang , Yan Zhao , Xue Dong , Wei Huang

This study develops a dynamic lateral boundary condition for the Weather Research and Forecasting (WRF) model by integrating updates to sea surface temperature (SST) and roughness length (Z₀). By incorporating an ocean model and roughness schemes, time-varying SST and Z₀ were employed to enhance wind simulations over coastal areas. The results demonstrate significant improvements in the accuracy of wind speed and direction simulations, with consistent error reduction across observations. Statistical metrics, including correlation coefficients, mean bias, and root mean square error, highlight these improvements and underscore the need for continuous refinement of boundary conditions to ensure reliable meteorological forecasts. The impact of SST and Z₀ updates is particularly notable under stable atmospheric stratification, where they reduce wind speeds near the sea surface and exhibit spatial and temporal variability, with coastal regions responding more strongly than offshore areas. Additionally, the concurrent application of Z₀ updates mitigates anomalies that might arise from SST updates alone, emphasizing the importance of integrating both parameters for balanced and robust simulations. Overall, this work provides critical insights into the role of boundary condition updates in advancing offshore wind simulations, contributing to more informed decision-making and improved efficiency in wind energy generation.

本研究通过整合更新海面温度（SST）和粗糙度长度（Z₀），为天气研究和预报（WRF）模式开发了一种动态横向边界条件。通过整合海洋模式和粗糙度方案，采用时变海表温度和 Z₀ 来增强沿海地区的风模拟。结果表明，风速和风向模拟的准确性明显提高，观测误差持续减少。包括相关系数、平均偏差和均方根误差在内的统计指标突出表明了这些改进，并强调需要不断完善边界条件，以确保气象预报的可靠性。在大气分层稳定的情况下，SST 和 Z₀ 更新的影响尤为显著，它们会降低海面附近的风速，并表现出时空变异性，沿海地区比近海地区反应更强烈。此外，Z₀更新的同时应用减轻了仅靠 SST 更新可能产生的异常，强调了整合这两个参数对平衡和稳健模拟的重要性。总之，这项工作为边界条件更新在推进海上风力模拟中的作用提供了重要见解，有助于做出更明智的决策和提高风能发电的效率。

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引用次数: 0

Forecasting ionospheric VTEC in the Indian equatorial and low-latitude region amid geomagnetic storms using the VECM model

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-10 DOI: 10.1016/j.dynatmoce.2025.101541

Sumitra Padmanabhan , Daivik Padmanabhan , Yogesh Jadhav , Harsh Taneja

Geomagnetic storms are one of the major causes of irregular variations in the ionosphere. The effect of a geomagnetic storm on Vertical Total Electron Content (VTEC) variation, especially in the equatorial regions, is very complex and uncertain due to the Equatorial Ionization Anomaly (EIA). Thus, the VTEC exhibits large and complex spatio-temporal variations in the equatorial region. A deeper study of the relationship between the past values of geomagnetic storm variables and the present value of VTEC, and vice versa can help better understand the dynamics of the variables and processes’ long-term equilibrium between the variables. Causal dependence between the variables has been found helpful in determining the temporal dependencies in econometrics where parameters are uncertain, and variability patterns are complex. In this study, causality was used for investigating the impact of the highly complex geomagnetic processes on VTEC. Causality between the geomagnetic indices and deviation in VTEC was investigated to understand the interconnection between the dynamical variables, the nonlinear correlations between them, and the underlying physical processes to predict the deviation in VTEC. Based on causality, a Vector Error-Correction (VECM) forecast model was developed for a two-step ahead forecast of VTEC on geomagnetic storm days. The forecast results were compared with the actual values of GPS VTEC and the International Reference Ionosphere (IRI) model. Two metrics, namely RMSE and the correlation coefficient, were used to test the performance. The forecasted values were compared with the actual values, and the RMSE and correlation coefficients were calculated. The model’s performance was also compared with the reference model IRI 2016. For most of the days, the model could predict with low RMSE for two-step-ahead prediction (1 h).

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引用次数: 0

On the connection between large-scale climate indices and rainfall variability in Iraq

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-08 DOI: 10.1016/j.dynatmoce.2025.101540

Sherien Fadhel , Dawei Han

This study investigates the teleconnection between climate indices and rainfall variability in Iraq to identify the factors influencing rainfall variability. The correlation between seven climate indices and rainfall variability across eight Iraqi cities was analyzed for the period 1951–2020, with a focus on January, the month with the highest amount of rainfall for most cities in the country. Bivariate wavelet coherence (WTC) and improved partial wavelet coherence (IPWC) methods were adopted for the analysis, and the significance of the correlations was quantified by the percentage of significant coherence (PoSC). The study aimed to determine whether specific climate indices have major connection with rainfall variability in Iraq, and whether this connection is identified through integration with other indices (i.e. using WTC), or by removing the mutual dependence of these climate indices (i.e. using IPWC). Results indicated that IPWC generally yielded a higher PoSC than WTC. The highest PoSC for the IPWC was achieved not by eliminating all climate indices but by selectively removing certain indices while retaining others. For instance, each of the three indices (PDO, AMO, DMI) produced the highest PoSC by removing four climate indices and keeping both the SOI and the NAO. In addition, the correlation between the reconstructed rainfall and the seven climate indices on different frequency bands explains and confirms the results of deleting some indices and keeping others to gain the greatest revelation on rainfall variability since no single dominant index can fully explain such rainfall variation. In addition, the combined NAO & SOI indices found to be the main connection with rainfall variability over Iraq, especially when this combination is linked to any SST indices. However, the second driver of rainfall variability over Iraq was revealed by the combined WeMO & SOI indices when they are linked to any climate indices. The above findings were found to be helpful and improved the accuracy of rainfall prediction. This study on searching for the drivers that affect the rainfall variation through multiple Large-Scale Climate Oscillation (LSCO) indices is the first in Iraq, and it has importance for other studies such as rainfall prediction, flooding analysis, and flooding mitigation.

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引用次数: 0

Projected changes in wind speed and wind energy resources over the Persian Gulf based on bias corrected CMIP6 models

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-06 DOI: 10.1016/j.dynatmoce.2025.101539

Amirmahdi Gohari , Adem Akpınar

This study investigates future wind speed and wind energy changes in the Persian Gulf using a multi-model ensemble mean (MMM) derived from 20 CMIP6 models under the SSP5–8.5 scenario. ERA5 reanalysis wind speed data for the historical period (1995–2015) is compared to projections for the mid-future (2040–2059) and far-future (2080–2099). Quantile mapping based on Weibull distribution as a bias correction technique applied to the raw future data to obtain more reliable projections. Results show suitable wind conditions for power generation are expected to increase slightly, by 1.16 % in the mid-future and 0.75 % in the far-future. However, average annual wind speed and wind power density are projected to decrease by up to 2 % and 7 % respectively. The winter season is consistently shown to have the highest average wind speed, projected to increase over 5–7 % in the future. Spatial analysis identifies current and future wind energy hot spots, with a northward shift by the far-future. Assessments of variability over time highlight potential future alterations. The future change analysis reveals irregular regional shifts, indicating decreases in wind strength nearshore in the northern Gulf, while the southern part may experience increases, suggesting a promising trend for wind energy potential there.

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引用次数: 0

Future projections of climate variables and meteorological drought: Insight from CMIP6 models in Southeast Ethiopia

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-02-05 DOI: 10.1016/j.dynatmoce.2025.101538

Amanuel Tsegaye Tadase , Andinet Kebede Tekile

Climate change has profound effects on precipitation, temperature, and meteorological drought patterns. This study addressed the knowledge gap regarding the future impacts of climate change on these variables in the Arsi Zone, Southeast Ethiopia. By utilizing data simulation from the Coupled Model Intercomparison Phase six (CMIP6) under two shared socioeconomic pathways (SSP2–4.5 and SSP5–8.5), future climatic conditions were projected. The quantile mapping (QM) bias correction technique was implemented in R to improve reliability. The nonparametric Mann–Kendall method and the standardized precipitation index (SPI-3) were employed for the climate variables trend analysis and to estimate drought characteristics, respectively. The findings of this study indicated an increasing trend in future precipitation and maximum temperature across both socioeconomic pathway scenarios from 2020 to 2100, with a more pronounced increase under the SSP5–8.5 scenario. The drought duration, severity, and intensity were also projected to increase from 1985–2014–2020–2049 under both scenarios. The intensity increased by 0.26 and 0.15 under SSP2–4.5 and SSP5–8.5, respectively; however, these values exhibited different trends in the two scenarios from 2020 to 2049–2080–2100. The SSP2–4.5 scenario suggested more frequent drought events, requiring specific strategies for water resource management. However, the SSP5–8.5 scenario exhibited variability in drought projections. As conclusion, there is a need for specific strategies to address the more frequent drought events projected under the SSP2–4.5 scenario, whereas the SSP5–8.5 scenario requires adaptable strategies due to the variable frequencies and it underlines the urgent need for comprehensive adaptation and mitigation strategies.

{"title":"Future projections of climate variables and meteorological drought: Insight from CMIP6 models in Southeast Ethiopia","authors":"Amanuel Tsegaye Tadase , Andinet Kebede Tekile","doi":"10.1016/j.dynatmoce.2025.101538","DOIUrl":"10.1016/j.dynatmoce.2025.101538","url":null,"abstract":"<div><div>Climate change has profound effects on precipitation, temperature, and meteorological drought patterns. This study addressed the knowledge gap regarding the future impacts of climate change on these variables in the Arsi Zone, Southeast Ethiopia. By utilizing data simulation from the Coupled Model Intercomparison Phase six (CMIP6) under two shared socioeconomic pathways (SSP2–4.5 and SSP5–8.5), future climatic conditions were projected. The quantile mapping (QM) bias correction technique was implemented in R to improve reliability. The nonparametric Mann–Kendall method and the standardized precipitation index (SPI-3) were employed for the climate variables trend analysis and to estimate drought characteristics, respectively. The findings of this study indicated an increasing trend in future precipitation and maximum temperature across both socioeconomic pathway scenarios from 2020 to 2100, with a more pronounced increase under the SSP5–8.5 scenario. The drought duration, severity, and intensity were also projected to increase from 1985–2014–2020–2049 under both scenarios. The intensity increased by 0.26 and 0.15 under SSP2–4.5 and SSP5–8.5, respectively; however, these values exhibited different trends in the two scenarios from 2020 to 2049–2080–2100. The SSP2–4.5 scenario suggested more frequent drought events, requiring specific strategies for water resource management. However, the SSP5–8.5 scenario exhibited variability in drought projections. As conclusion, there is a need for specific strategies to address the more frequent drought events projected under the SSP2–4.5 scenario, whereas the SSP5–8.5 scenario requires adaptable strategies due to the variable frequencies and it underlines the urgent need for comprehensive adaptation and mitigation strategies.</div></div>","PeriodicalId":50563,"journal":{"name":"Dynamics of Atmospheres and Oceans","volume":"110 ","pages":"Article 101538"},"PeriodicalIF":1.9,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143350865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Climate variability and heat wave dynamics in India: Insights from land- atmospheric interactions

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-01-30 DOI: 10.1016/j.dynatmoce.2025.101537

C.S. Neethu, B. Abish

Heat waves have emerged as one of the most severe and destructive meteorological phenomena, significantly threatening human health, agricultural productivity, and ecosystems due to their increasing frequency, duration, and intensity. In India, these extreme events predominantly occur during the pre-monsoon months (March to mid-June), with recent years (2016, 2019, 2022, and 2023) showing a clear intensification in their occurrence. This study aims to explore the dynamics of heat waves, synoptic conditions, surface land-atmosphere interactions, and regional variations in recent years across India, utilizing maximum temperature data from the India Meteorological Department (IMD) and heat wave indices to evaluate their intensity and impact. Analysis of maximum temperature data and heatwave indices highlights a notable rise in heatwave frequency and duration, particularly in northern and central India. The 2-meter (2 m) temperature anomaly in north, central, and southern India exceeded 2.5°C, while the 925hPa temperature showed significant warming trends in north and northwest India. The analysis of the spatial distribution of the planetary boundary layer (PBL) and total cloud cover (TCC) indicates reduced cloud cover and an increased PBL, intensifying heat wave conditions across north and central regions. The warm air advection and sinking air in the descending limb of the Walker circulation ensured a stable and drier atmosphere, favoring heatwave conditions. Moreover, a persistent anticyclonic circulation and its associated high-pressure system enabled heat-trapping within the atmosphere, leading to prolonged and intensified heat wave conditions. The study indicates a shift in the position and strength of the subtropical jet stream (STJ) during these years, highlighting its significant role in developing and intensifying heat waves.

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引用次数: 0

Satellite-derived ocean color data for monitoring pCO2 dynamics in the North Indian Ocean

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-01-22 DOI: 10.1016/j.dynatmoce.2025.101534

Ibrahim Shaik , M.P. Fida Fathima , P.V. Nagamani , Sandesh Yadav , Sibu Behera , Yash Manmode , G. Srinivasa Rao

The partial pressure of carbon dioxide (pCO₂) in the North Indian Ocean (NIO) undergoes significant variations due to factors such as biological activity, ocean circulation patterns, and atmospheric influences. Understanding these variations is crucial for assessing the ocean role in the global carbon cycle and their impact on climate change. Estimating pCO₂ through in-situ platforms is challenging due to the time-consuming, expensive, and complex nature of water sample collection, particularly under rough oceanic conditions. Conversely, remote sensing technology offers high spatiotemporal resolution data over extensive synoptic scales, making it a valuable tool for pCO₂ estimation. Current models for estimating pCO₂ in the NIO region are limited due to the improper selection of model parameters and the scarcity of in-situ measurements, highlighting the need for a more accurate approach. This study develops a Multiparametric Linear Regression (MLR) method, integrating satellite and in-situ observations of sea surface temperature (SST), sea surface salinity (SSS), and chlorophyll-a (Chla) concentration. To develop and validate this model, in-situ data were sourced from the Global Ocean Data Analysis Project (GLODAP). Validation results showed that the proposed MLR approach outperformed existing global models, achieving low mean relative error (MRE = 0.08), mean normalized bias (MNB = 0.013), and root mean square error (RMSE = 7.26 μatm), with a high correlation coefficient (R² = 0.96). This study has the potential to improve understanding of carbon dynamics in the NIO region and its contribution to the global carbon cycle. The pCO₂ maps generated in this study improve climate modeling and monitoring, supporting predictions and mitigation efforts. This accurate model also aids policy-making, environmental management, and ecological assessments.

{"title":"Satellite-derived ocean color data for monitoring pCO2 dynamics in the North Indian Ocean","authors":"Ibrahim Shaik , M.P. Fida Fathima , P.V. Nagamani , Sandesh Yadav , Sibu Behera , Yash Manmode , G. Srinivasa Rao","doi":"10.1016/j.dynatmoce.2025.101534","DOIUrl":"10.1016/j.dynatmoce.2025.101534","url":null,"abstract":"<div><div>The partial pressure of carbon dioxide (<em>p</em>CO<sub>2</sub>) in the North Indian Ocean (NIO) undergoes significant variations due to factors such as biological activity, ocean circulation patterns, and atmospheric influences. Understanding these variations is crucial for assessing the ocean role in the global carbon cycle and their impact on climate change. Estimating <em>p</em>CO<sub>2</sub> through in-situ platforms is challenging due to the time-consuming, expensive, and complex nature of water sample collection, particularly under rough oceanic conditions. Conversely, remote sensing technology offers high spatiotemporal resolution data over extensive synoptic scales, making it a valuable tool for <em>p</em>CO<sub>2</sub> estimation. Current models for estimating <em>p</em>CO<sub>2</sub> in the NIO region are limited due to the improper selection of model parameters and the scarcity of in-situ measurements, highlighting the need for a more accurate approach. This study develops a Multiparametric Linear Regression (MLR) method, integrating satellite and in-situ observations of sea surface temperature (SST), sea surface salinity (SSS), and chlorophyll-a (Chla) concentration. To develop and validate this model, in-situ data were sourced from the Global Ocean Data Analysis Project (GLODAP). Validation results showed that the proposed MLR approach outperformed existing global models, achieving low mean relative error (MRE = 0.08), mean normalized bias (MNB = 0.013), and root mean square error (RMSE = 7.26 μatm), with a high correlation coefficient (R<sup>2</sup> = 0.96). This study has the potential to improve understanding of carbon dynamics in the NIO region and its contribution to the global carbon cycle. The <em>p</em>CO<sub>2</sub> maps generated in this study improve climate modeling and monitoring, supporting predictions and mitigation efforts. This accurate model also aids policy-making, environmental management, and ecological assessments.</div></div>","PeriodicalId":50563,"journal":{"name":"Dynamics of Atmospheres and Oceans","volume":"110 ","pages":"Article 101534"},"PeriodicalIF":1.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characteristics and potential drivers of extreme high-temperature event frequency in Eurasia

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-01-22 DOI: 10.1016/j.dynatmoce.2025.101536

Xiangqin Xie , Run Liu , Ruyuan Xiao , Sijia Hu , Caixian Huang , Yongze Bi , Yifan Xu

This study investigates decadal variations in the frequency and intensity of extreme high temperature events (EHEs) during the summer months of July and August across the Northern Hemisphere from 1979 to 2023. Research results indicate that the frequency and intensity of EHEs on the Eurasian continent have increased more rapidly than in other Northern Hemisphere landmasses over time. By applying Empirical Orthogonal Function analysis, two dominant modes of EHEs were identified: a spatial consistency pattern and a quadrupole anomaly pattern. The spatial consistency pattern shows significant anomalies centered around the Caspian Sea and East Asia, with a notable upward trend in intensity. This pattern is strongly associated with atmospheric warming and increased sea surface temperatures in the tropical North Atlantic, which amplifies the North Atlantic-Eurasian wave train. The eastward propagation of wave activity flux, driven by the shifting positive geopotential height anomaly, further enhances the frequency and intensity of EHEs. The quadrupole anomaly pattern is characterized by four centers located in the mid-latitude region (30°N-50°N, 25°E-150°E), West Asia-South Asia-Southeast Asia, Central Europe-Northern Europe, and East Asia-Eastern West Asia. The EHEs in these regions exhibit anti-phase characteristics, meaning that while one region experiences higher-than-average frequency of EHEs, others simultaneously show lower-than-average frequency of EHEs. The formation of this quadrupole anomaly pattern is closely associated with the negative phase of the North Atlantic Oscillation (NAO). NAO influences regional temperatures by modulating the jet stream and geopotential height, forming anticyclones or cyclones that, in turn, increase or decrease EHEs. Under NAO influence, a double jet state is formed, and a blocking anticyclone emerges in the weak wind zone between the two zonal wind maxima, thus increasing the EHEs in local areas. This study underscores the importance of understanding these distinct patterns and their underlying mechanisms to better predict and manage the regional impacts of extreme heat in a changing climate.

{"title":"Characteristics and potential drivers of extreme high-temperature event frequency in Eurasia","authors":"Xiangqin Xie , Run Liu , Ruyuan Xiao , Sijia Hu , Caixian Huang , Yongze Bi , Yifan Xu","doi":"10.1016/j.dynatmoce.2025.101536","DOIUrl":"10.1016/j.dynatmoce.2025.101536","url":null,"abstract":"<div><div>This study investigates decadal variations in the frequency and intensity of extreme high temperature events (EHEs) during the summer months of July and August across the Northern Hemisphere from 1979 to 2023. Research results indicate that the frequency and intensity of EHEs on the Eurasian continent have increased more rapidly than in other Northern Hemisphere landmasses over time. By applying Empirical Orthogonal Function analysis, two dominant modes of EHEs were identified: a spatial consistency pattern and a quadrupole anomaly pattern. The spatial consistency pattern shows significant anomalies centered around the Caspian Sea and East Asia, with a notable upward trend in intensity. This pattern is strongly associated with atmospheric warming and increased sea surface temperatures in the tropical North Atlantic, which amplifies the North Atlantic-Eurasian wave train. The eastward propagation of wave activity flux, driven by the shifting positive geopotential height anomaly, further enhances the frequency and intensity of EHEs. The quadrupole anomaly pattern is characterized by four centers located in the mid-latitude region (30°N-50°N, 25°E-150°E), West Asia-South Asia-Southeast Asia, Central Europe-Northern Europe, and East Asia-Eastern West Asia. The EHEs in these regions exhibit anti-phase characteristics, meaning that while one region experiences higher-than-average frequency of EHEs, others simultaneously show lower-than-average frequency of EHEs. The formation of this quadrupole anomaly pattern is closely associated with the negative phase of the North Atlantic Oscillation (NAO). NAO influences regional temperatures by modulating the jet stream and geopotential height, forming anticyclones or cyclones that, in turn, increase or decrease EHEs. Under NAO influence, a double jet state is formed, and a blocking anticyclone emerges in the weak wind zone between the two zonal wind maxima, thus increasing the EHEs in local areas. This study underscores the importance of understanding these distinct patterns and their underlying mechanisms to better predict and manage the regional impacts of extreme heat in a changing climate.</div></div>","PeriodicalId":50563,"journal":{"name":"Dynamics of Atmospheres and Oceans","volume":"110 ","pages":"Article 101536"},"PeriodicalIF":1.9,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quasi-homogeneous regions of climatic distributions of wind wave parameters in the Black Sea

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS

Dynamics of Atmospheres and Oceans

Pub Date : 2025-01-20 DOI: 10.1016/j.dynatmoce.2025.101535

Boris V. Divinsky, Yana V. Saprykina

The main aim of the study is to identify in the Black Sea quasi-homogeneous spatial areas and corresponding relevant features, the climatic statistical characteristics of which will determine these areas. Numerical modeling and discriminant analysis were applied. As a result of modeling an array of wind wave parameters for the period of 45 years (1979–2023) was obtained. The values of the main parameters (significant wave heights, spectrum peak periods, propagation directions) for this period at 92 points uniformly distributed over the Black Sea were analyzed. The main features, by which the zoning of the Black Sea was carried out, were climatic repeatabilities of the following parameters: significant wave heights in the ranges of h_s< 1 m, 1 <h_s< 3 m, 3 <h_s< 5 m, h_s> 5 m; and spectrum peak periods in the ranges t_p< 3 s, 3 <t_p< 6 s, 6 <t_p< 9 s, t_p> 9 s. According discriminant analysis six quasi-homogeneous areas (clusters) in the Black Sea were identified. The main zoning parameters are wave heights in the ranges 3 <h_s< 5 m and h_s> 5 m and periods 6 <t_p< 9 s. The identified clusters are quite homogeneous in the repeatability of wave action of the north-eastern and north-western directions. The obtained quasi-homogeneous areas of the Black Sea significantly refine the zoning obtained earlier and can be used to study and forecast sea climate change.

{"title":"Quasi-homogeneous regions of climatic distributions of wind wave parameters in the Black Sea","authors":"Boris V. Divinsky, Yana V. Saprykina","doi":"10.1016/j.dynatmoce.2025.101535","DOIUrl":"10.1016/j.dynatmoce.2025.101535","url":null,"abstract":"<div><div>The main aim of the study is to identify in the Black Sea quasi-homogeneous spatial areas and corresponding relevant features, the climatic statistical characteristics of which will determine these areas. Numerical modeling and discriminant analysis were applied. As a result of modeling an array of wind wave parameters for the period of 45 years (1979–2023) was obtained. The values of the main parameters (significant wave heights, spectrum peak periods, propagation directions) for this period at 92 points uniformly distributed over the Black Sea were analyzed. The main features, by which the zoning of the Black Sea was carried out, were climatic repeatabilities of the following parameters: significant wave heights in the ranges of <em>h</em><sub>s</sub>< 1 m, 1 <<em>h</em><sub>s</sub>< 3 m, 3 <<em>h</em><sub>s</sub>< 5 m, <em>h</em><sub>s</sub>> 5 m; and spectrum peak periods in the ranges <em>t</em><sub>p</sub>< 3 s, 3 <<em>t</em><sub>p</sub>< 6 s, 6 <<em>t</em><sub>p</sub>< 9 s, <em>t</em><sub>p</sub>> 9 s. According discriminant analysis six quasi-homogeneous areas (clusters) in the Black Sea were identified. The main zoning parameters are wave heights in the ranges 3 <<em>h</em><sub>s</sub>< 5 m and <em>h</em><sub>s</sub>> 5 m and periods 6 <<em>t</em><sub>p</sub>< 9 s. The identified clusters are quite homogeneous in the repeatability of wave action of the north-eastern and north-western directions. The obtained quasi-homogeneous areas of the Black Sea significantly refine the zoning obtained earlier and can be used to study and forecast sea climate change.</div></div>","PeriodicalId":50563,"journal":{"name":"Dynamics of Atmospheres and Oceans","volume":"110 ","pages":"Article 101535"},"PeriodicalIF":1.9,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143177319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0