首页 > 最新文献

Journal of Atmospheric and Solar-Terrestrial Physics最新文献

英文 中文
Analysis of LST, NDVI, and UHI patterns for urban climate using Landsat-9 satellite data in Delhi 利用 Landsat-9 卫星数据分析德里城市气候的 LST、NDVI 和 UHI 模式
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-28 DOI: 10.1016/j.jastp.2024.106359
Bilal Ahmad , Mohammad Bareeq Najar , Shamshad Ahmad
The present study is based on remote sensing techniques focusing on Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) to investigate their influence on land use and land cover dynamics, and the assessment of the Urban Heat Island (UHI) effect in Delhi, India. The objective of this study is to calculate LST, NDVI, and UHI values to understand the changes in LULC patterns, urbanization, and temperature increase within the city. Unlike previous studies conducted with Landsat-8, the present study employs Landsat-9 data, ensuring a higher level of authenticity in the results. Landsat-9, equipped with state-of-the-art sensors and instrumentation, provides superior data quality, enhanced image resolution, and advanced capabilities for precise monitoring and analysis. The methodology encompasses six steps for LST retrieval, enabling the calculation of UHI values and intensity. Ground data from 32 meteorological stations validate the LST results. Pearson correlation coefficients between LST and NDVI exhibit correlations ranging from −0.58 to −0.68 for three dates. On Dec 8, 2023, there is a weak negative correlation of −0.004. The analysis of changing land cover with variation in NDVI and LST unveils a diverse landscape, primarily characterised by green cover (47.34%), followed by built-up area (44.57%), barren land (7.57%), and water (0.52%). The study identifies the minimum value of UHI intensity for Delhi to be 8.13 °C on 26-Feb 2023 and the maximum value of UHI was estimated 10.29 °C on 2-June 2023. The study of Urban Heat Island (UHI) patterns revealed distinctive seasonal trends. The urban areas exhibited relatively cooler temperatures compared to surrounding rural regions on Dec 8, 2023. The conclusion drawn from this comprehensive analysis is that rapid urbanization in Delhi has significantly contributed to the increase in LST and UHI values. This rise can largely be attributed to the extensive use of concrete in construction activities, which exacerbates the UHI effect. Moreover, this analysis signifies the dynamic nature of UHI and emphasizes the urgency for strategic urban planning and climate-sensitive design approaches. Implementing such measures can create more sustainable and resilient urban environments.
本研究基于遥感技术,重点关注印度德里的地表温度(LST)和归一化植被指数(NDVI),以调查它们对土地利用和土地覆被动态的影响,并评估城市热岛(UHI)效应。本研究的目的是计算 LST、NDVI 和 UHI 值,以了解城市内 LULC 模式、城市化和气温上升的变化。与以往使用 Landsat-8 进行的研究不同,本研究使用了 Landsat-9 数据,以确保研究结果具有更高的真实性。Landsat-9 配备了最先进的传感器和仪器,数据质量上乘,图像分辨率更高,具有精确监测和分析的先进能力。该方法包括六个 LST 检索步骤,可计算出 UHI 值和强度。来自 32 个气象站的地面数据验证了 LST 结果。LST 与 NDVI 之间的皮尔逊相关系数在三个日期显示出 -0.58 至 -0.68 的相关性。在 2023 年 12 月 8 日,两者之间存在-0.004 的微弱负相关。通过对随 NDVI 和 LST 变化而变化的土地覆被进行分析,发现了一个多样化的地貌景观,其主要特征是绿色覆被(47.34%),其次是建筑区(44.57%)、贫瘠土地(7.57%)和水域(0.52%)。研究发现,2023 年 2 月 26 日德里的 UHI 强度最小值为 8.13 °C,2023 年 6 月 2 日的 UHI 最大值估计为 10.29 °C。城市热岛(UHI)模式研究揭示了独特的季节性趋势。与周边农村地区相比,2023 年 12 月 8 日城市地区的气温相对较低。综合分析得出的结论是,德里的快速城市化在很大程度上导致了 LST 和 UHI 值的上升。这种上升在很大程度上归因于建筑活动中大量使用混凝土,从而加剧了 UHI 效应。此外,这项分析表明了 UHI 的动态性质,并强调了战略性城市规划和气候敏感性设计方法的紧迫性。实施这些措施可以创造更可持续和更具弹性的城市环境。
{"title":"Analysis of LST, NDVI, and UHI patterns for urban climate using Landsat-9 satellite data in Delhi","authors":"Bilal Ahmad ,&nbsp;Mohammad Bareeq Najar ,&nbsp;Shamshad Ahmad","doi":"10.1016/j.jastp.2024.106359","DOIUrl":"10.1016/j.jastp.2024.106359","url":null,"abstract":"<div><div>The present study is based on remote sensing techniques focusing on Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) to investigate their influence on land use and land cover dynamics, and the assessment of the Urban Heat Island (UHI) effect in Delhi, India. The objective of this study is to calculate LST, NDVI, and UHI values to understand the changes in LULC patterns, urbanization, and temperature increase within the city. Unlike previous studies conducted with Landsat-8, the present study employs Landsat-9 data, ensuring a higher level of authenticity in the results. Landsat-9, equipped with state-of-the-art sensors and instrumentation, provides superior data quality, enhanced image resolution, and advanced capabilities for precise monitoring and analysis. The methodology encompasses six steps for LST retrieval, enabling the calculation of UHI values and intensity. Ground data from 32 meteorological stations validate the LST results. Pearson correlation coefficients between LST and NDVI exhibit correlations ranging from −0.58 to −0.68 for three dates. On Dec 8, 2023, there is a weak negative correlation of −0.004. The analysis of changing land cover with variation in NDVI and LST unveils a diverse landscape, primarily characterised by green cover (47.34%), followed by built-up area (44.57%), barren land (7.57%), and water (0.52%). The study identifies the minimum value of UHI intensity for Delhi to be 8.13 °C on 26-Feb 2023 and the maximum value of UHI was estimated 10.29 °C on 2-June 2023. The study of Urban Heat Island (UHI) patterns revealed distinctive seasonal trends. The urban areas exhibited relatively cooler temperatures compared to surrounding rural regions on Dec 8, 2023. The conclusion drawn from this comprehensive analysis is that rapid urbanization in Delhi has significantly contributed to the increase in LST and UHI values. This rise can largely be attributed to the extensive use of concrete in construction activities, which exacerbates the UHI effect. Moreover, this analysis signifies the dynamic nature of UHI and emphasizes the urgency for strategic urban planning and climate-sensitive design approaches. Implementing such measures can create more sustainable and resilient urban environments.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106359"},"PeriodicalIF":1.8,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417203","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
Unveiling the impact of cosmic rays and solar activities on climate through optimized boost algorithms 通过优化助推算法揭示宇宙射线和太阳活动对气候的影响
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-26 DOI: 10.1016/j.jastp.2024.106360
Ahmet Polatoğlu , Enes Gül
This investigation explores the enhancement of climate anomaly predictions by incorporating Solar Sunspot Number (SSN) and Cosmic Ray (CR) data into climate models. Leveraging XGBoost and CatBoost regression methodologies enhanced by Atom Search Optimization (ASO) and Nuclear Reaction Optimization (NRO) for predictive analysis. Utilizing a dataset spanning from 1965 to 2020, comprising 672 data points per climate parameter, the study delves into the dynamics between CR flux, SSN variability, and climate parameters. The models aimed to forecast variations in total precipitation anomaly (TPA), total cloud cover anomaly (TCCA), and sea surface temperature anomaly (SSTA) based on decadal solar cycle activities and CR data. Our findings reveal the significant impact of integrating SSN and CR data into environmental prediction models for TCCA, TPA, and SSTA, employing CatBoost and XGBoost machine learning (ML) algorithms. Performance evaluation, centered on root mean square error (RMSE), mean absolute error (MAE), coefficient of determination (R2), and Nash-Sutcliffe efficiency (NSE), illuminated the efficacy of ASO and NRO in model optimization, particularly under scenarios with and without SSN/CR data inclusion. The analytical outcomes underscore the enhanced prediction accuracy for TCCA, TPA, and SSTA when incorporating SSN and CR data, with ASO generally outperforming NRO in optimizing model parameters. Our regression models, optimized using ASO and NRO, showed a marked improvement in SSTA forecasts, with an increase in the R2 value from 0.73 to 0.76 when SSN/CR data were not included. The CatBoost was superior the XGBoost models with results of four error metrics. These results underscore the critical role of solar activity data and optimized algorithms in enhancing the accuracy and reliability of climate modeling. This study underscores the utility of advanced ML techniques and the importance of strategic variable selection in environmental modeling, offering new insights into the complex interactions between solar activity, CR, and climate dynamics.
这项研究探讨了通过将太阳黑子数(SSN)和宇宙射线(CR)数据纳入气候模型来增强气候异常预测的问题。利用原子搜索优化(ASO)和核反应优化(NRO)增强的 XGBoost 和 CatBoost 回归方法进行预测分析。该研究利用从 1965 年到 2020 年的数据集,每个气候参数包含 672 个数据点,深入研究了 CR 通量、SSN 变率和气候参数之间的动态关系。模型旨在根据十年太阳周期活动和CR数据预测总降水异常(TPA)、总云量异常(TCCA)和海面温度异常(SSTA)的变化。我们的研究结果表明,采用 CatBoost 和 XGBoost 机器学习(ML)算法,将 SSN 和 CR 数据整合到 TCCA、TPA 和 SSTA 的环境预测模型中会产生重大影响。以均方根误差 (RMSE)、平均绝对误差 (MAE)、判定系数 (R2) 和纳什-苏特克利夫效率 (NSE) 为核心的性能评估表明了 ASO 和 NRO 在模型优化方面的功效,尤其是在包含和不包含 SSN/CR 数据的情况下。分析结果表明,在纳入 SSN 和 CR 数据时,TCCA、TPA 和 SSTA 的预测准确性得到了提高,ASO 在优化模型参数方面普遍优于 NRO。我们使用 ASO 和 NRO 对回归模型进行了优化,结果表明 SSTA 预测有明显改善,当不包含 SSN/CR 数据时,R2 值从 0.73 增加到 0.76。在四个误差指标上,CatBoost 模型优于 XGBoost 模型。这些结果强调了太阳活动数据和优化算法在提高气候建模的准确性和可靠性方面的关键作用。这项研究强调了先进的 ML 技术的实用性以及在环境建模中战略性变量选择的重要性,为太阳活动、CR 和气候动力学之间复杂的相互作用提供了新的见解。
{"title":"Unveiling the impact of cosmic rays and solar activities on climate through optimized boost algorithms","authors":"Ahmet Polatoğlu ,&nbsp;Enes Gül","doi":"10.1016/j.jastp.2024.106360","DOIUrl":"10.1016/j.jastp.2024.106360","url":null,"abstract":"<div><div>This investigation explores the enhancement of climate anomaly predictions by incorporating Solar Sunspot Number (SSN) and Cosmic Ray (CR) data into climate models. Leveraging XGBoost and CatBoost regression methodologies enhanced by Atom Search Optimization (ASO) and Nuclear Reaction Optimization (NRO) for predictive analysis. Utilizing a dataset spanning from 1965 to 2020, comprising 672 data points per climate parameter, the study delves into the dynamics between CR flux, SSN variability, and climate parameters. The models aimed to forecast variations in total precipitation anomaly (TPA), total cloud cover anomaly (TCCA), and sea surface temperature anomaly (SSTA) based on decadal solar cycle activities and CR data. Our findings reveal the significant impact of integrating SSN and CR data into environmental prediction models for TCCA, TPA, and SSTA, employing CatBoost and XGBoost machine learning (ML) algorithms. Performance evaluation, centered on root mean square error (RMSE), mean absolute error (MAE), coefficient of determination (R<sup>2</sup>), and Nash-Sutcliffe efficiency (NSE), illuminated the efficacy of ASO and NRO in model optimization, particularly under scenarios with and without SSN/CR data inclusion. The analytical outcomes underscore the enhanced prediction accuracy for TCCA, TPA, and SSTA when incorporating SSN and CR data, with ASO generally outperforming NRO in optimizing model parameters. Our regression models, optimized using ASO and NRO, showed a marked improvement in SSTA forecasts, with an increase in the R<sup>2</sup> value from 0.73 to 0.76 when SSN/CR data were not included. The CatBoost was superior the XGBoost models with results of four error metrics. These results underscore the critical role of solar activity data and optimized algorithms in enhancing the accuracy and reliability of climate modeling. This study underscores the utility of advanced ML techniques and the importance of strategic variable selection in environmental modeling, offering new insights into the complex interactions between solar activity, CR, and climate dynamics.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106360"},"PeriodicalIF":1.8,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416990","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
Analysis of the scintillation characteristics on the different satellite links derived from GPS observations and SCINDA data over Mbarara 根据姆巴拉拉上空的全球定位系统观测数据和 SCINDA 数据得出的不同卫星链路上的闪烁特性分析
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-24 DOI: 10.1016/j.jastp.2024.106353
Edward Jurua , Geoffrey Andima , Paschal Oleni , Emirant B. Amabayo
Ionospheric scintillation is a frequent phenomenon over the low latitude regions. However, the severity of the scintillation on the various satellite-receiver links is a function of space and time. Therefore in satellite applications such as positioning, messages on satellite to ground links that are not affected by scintillation should be used. In this paper we present the statistics of scintillation on the accessible satellite links over Mbarara for the period 2011 to 2017. We used scintillation indices from the Scintillation Network Decision Aid (SCINDA) at Mbarara (Geographic coordinate -0.62°N, 30.66°E, and dip latitude -9.3°N) together with a proxy for amplitude scintillation derived from the carrier-to-noise ratio observable on the L1 frequency of the multi-frequency GPS receiver at Mbarara (Geographic coordinate -0.60°N, 30.74°E, and dip latitude -10.2°N) to characterise scintillation on different satellite links. The results showed that the proxy closely relate to amplitude scintillation index S4. Based on the proxy and the scintillation indices, both amplitude and phase scintillation over Mbarara peaks from 20:00–22:00 LT. Scintillation climatology shows equinoctial asymmetry with more frequent scintillation during autumnal equinox than vernal equinox. The spatial scintillation characteristics show that scintillation over Mbarara is directional with the most active regions in the azimuth range of 150° to 210°. The most affected links were for GPS satellites designated by the Pseudo Random Noise (PRN) number as PRN 31 and PRN 25 for amplitude and phase scintillation respectively, and the least affected by both phase and amplitude scintillation were PRN 5 and PRN 17. Based on these observations, we suggest that data from PRN 31 and PRN 25 be used with caution for satellite applications over Mbarara especially during times of scintillation.
电离层闪烁是低纬度地区经常出现的现象。然而,各种卫星-接收器链路上闪烁的严重程度是空间和时间的函数。因此,在定位等卫星应用中,应使用不受闪烁影响的卫星到地面链路上的信息。在本文中,我们介绍了 2011 年至 2017 年期间姆巴拉拉上空可访问卫星链路的闪烁统计数据。我们使用了姆巴拉拉(地理坐标-0.62°N,30.66°E,倾角纬度-9.在此基础上,研究人员利用姆巴拉拉(地理坐标为北纬-0.62°,东经 30.66°,倾角纬度为北纬-9°)的闪烁网络决策辅助系统(SCINDA)以及从姆巴拉拉多频 GPS 接收机 L1 频率(地理坐标为北纬-0.60°,东经 30.74°,倾角纬度为北纬-10.2°)上观测到的载噪比得出的振幅闪烁替代值,对不同卫星链路上的闪烁进行了定性。结果表明,代用指标与振幅闪烁指数 S4 密切相关。根据代用指标和闪烁指数,姆巴拉拉上空的振幅闪烁和相位闪烁都在 20:00-22:00 LT 时段达到峰值。闪烁气候学显示出赤道不对称,秋分比春分闪烁更频繁。闪烁的空间特征表明,姆巴拉拉上空的闪烁具有方向性,最活跃的区域在方位角 ∼150°至 ∼210°之间。受影响最严重的链路是 GPS 卫星,其伪随机噪声(PRN)编号分别为 PRN 31 和 PRN 25(振幅闪烁和相位闪烁),受相位闪烁和振幅闪烁影响最小的是 PRN 5 和 PRN 17。基于这些观察结果,我们建议在姆巴拉拉上空的卫星应用中谨慎使用 PRN 31 和 PRN 25 的数据,尤其是在闪烁期间。
{"title":"Analysis of the scintillation characteristics on the different satellite links derived from GPS observations and SCINDA data over Mbarara","authors":"Edward Jurua ,&nbsp;Geoffrey Andima ,&nbsp;Paschal Oleni ,&nbsp;Emirant B. Amabayo","doi":"10.1016/j.jastp.2024.106353","DOIUrl":"10.1016/j.jastp.2024.106353","url":null,"abstract":"<div><div>Ionospheric scintillation is a frequent phenomenon over the low latitude regions. However, the severity of the scintillation on the various satellite-receiver links is a function of space and time. Therefore in satellite applications such as positioning, messages on satellite to ground links that are not affected by scintillation should be used. In this paper we present the statistics of scintillation on the accessible satellite links over Mbarara for the period 2011 to 2017. We used scintillation indices from the Scintillation Network Decision Aid (SCINDA) at Mbarara (Geographic coordinate -0.62°N, 30.66°E, and dip latitude -9.3°N) together with a proxy for amplitude scintillation derived from the carrier-to-noise ratio observable on the L1 frequency of the multi-frequency GPS receiver at Mbarara (Geographic coordinate -0.60°N, 30.74°E, and dip latitude -10.2°N) to characterise scintillation on different satellite links. The results showed that the proxy closely relate to amplitude scintillation index S4. Based on the proxy and the scintillation indices, both amplitude and phase scintillation over Mbarara peaks from 20:00–22:00 LT. Scintillation climatology shows equinoctial asymmetry with more frequent scintillation during autumnal equinox than vernal equinox. The spatial scintillation characteristics show that scintillation over Mbarara is directional with the most active regions in the azimuth range of <span><math><mo>∼</mo></math></span>150° to <span><math><mo>∼</mo></math></span>210°. The most affected links were for GPS satellites designated by the Pseudo Random Noise (PRN) number as PRN 31 and PRN 25 for amplitude and phase scintillation respectively, and the least affected by both phase and amplitude scintillation were PRN 5 and PRN 17. Based on these observations, we suggest that data from PRN 31 and PRN 25 be used with caution for satellite applications over Mbarara especially during times of scintillation.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106353"},"PeriodicalIF":1.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357582","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
Vertical Profiles of Black Carbon and Associated Radiative Properties over India: Inter-comparison of Measured and Reanalysis Data 印度上空的黑碳垂直剖面及相关辐射特性:测量数据与再分析数据的相互比较
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-24 DOI: 10.1016/j.jastp.2024.106358
Ashish Soni, Pawan S. Soyam, Mahen Konwar, Neelam Malap, Pramod Safai, Thara Prabhakaran
The significant uncertainties of Black Carbon (BC) radiative forcing are becoming an obstacle to the evaluation of their impacts and mitigation measures. One of the crucial reasons for this uncertainty could be the poorly constrained BC vertical profile. The BC has a lifetime of a few days to weeks and there is a clear pointer that it can be vertically transported through convection besides the horizontal advection. The present study aims for the intercomparison between the BC mass concentrations obtained through the aircraft-based observations and that derived from the selected Copernicus Atmosphere Monitoring Service (CAMS) reanalysis data over the three different locations of India, which is one of the largest emitters of BC aerosols. The aircraft-based BC observations were conducted from 0.5 to 7 km altitudes using Aethalometer during CAIPEEX (Cloud Aerosol Interaction and Precipitation Enhancement Experiment) Phase I campaigns from June to September 2009. The output of the present study suggests the CAMS reanalysis data significantly underestimated BC mass throughout the vertical profile with an average mass normalized mean bias of greater than −70% at all three locations. Furthermore, the vertical radiative forcing and heating rates of BC were also calculated for both observation and reanalysis data. The output depicts the net forcing due to CAMS simulated BC in all the layers were 1–12 folds lower over all the study regions compared with observed BC aerosols. Likewise, the estimated mean biases in heating rate were in the range of −0.001 to −0.190 K day−1 for all the vertical layers over the study locations. The possible reasons for these disparities could be poorly constrained emissions, especially aircraft emissions and/or their transformation schemes in aerosol modules. The present study emphasized that the validation of the vertical profile is also an essential factor for better constraints of the BC aerosols in climate models.
黑碳(BC)辐射强迫的重大不确定性正在成为评估其影响和减缓措施的障碍。造成这种不确定性的关键原因之一可能是对黑碳垂直剖面的约束不足。黑碳(BC)的寿命为几天到几周不等,除了水平平流之外,它还可以通过对流进行垂直传输。本研究旨在比较通过飞机观测获得的 BC 质量浓度和从选定的哥白尼大气监测服务(CAMS)再分析数据中得出的印度三个不同地点的 BC 质量浓度,印度是 BC 气溶胶的最大排放国之一。在 2009 年 6 月至 9 月的 CAIPEEX(云雾气溶胶相互作用和降水增强实验)第一阶段活动期间,使用 Aethalometer 在 0.5 至 7 千米高度进行了基于飞机的 BC 观测。本研究的结果表明,CAMS 再分析数据在整个垂直剖面上严重低估了 BC 质量,在所有三个地点的平均质量归一化平均偏差大于 -70%。此外,还计算了观测数据和再分析数据对 BC 的垂直辐射强迫和加热率。结果表明,与观测到的 BC 气溶胶相比,CAMS 模拟的 BC 气溶胶在所有研究区域各层的净强迫均低 1-12 倍。同样,在研究地点的所有垂直层中,加热率的估计平均偏差范围为-0.001 至-0.190 K 日-1。造成这些差异的可能原因是对排放物,尤其是飞机排放物和/或气溶胶模块中的转化方案的约束性较差。本研究强调,垂直剖面的验证也是气候模式中更好地约束 BC 气溶胶的一个重要因素。
{"title":"Vertical Profiles of Black Carbon and Associated Radiative Properties over India: Inter-comparison of Measured and Reanalysis Data","authors":"Ashish Soni,&nbsp;Pawan S. Soyam,&nbsp;Mahen Konwar,&nbsp;Neelam Malap,&nbsp;Pramod Safai,&nbsp;Thara Prabhakaran","doi":"10.1016/j.jastp.2024.106358","DOIUrl":"10.1016/j.jastp.2024.106358","url":null,"abstract":"<div><div>The significant uncertainties of Black Carbon (BC) radiative forcing are becoming an obstacle to the evaluation of their impacts and mitigation measures. One of the crucial reasons for this uncertainty could be the poorly constrained BC vertical profile. The BC has a lifetime of a few days to weeks and there is a clear pointer that it can be vertically transported through convection besides the horizontal advection. The present study aims for the intercomparison between the BC mass concentrations obtained through the aircraft-based observations and that derived from the selected Copernicus Atmosphere Monitoring Service (CAMS) reanalysis data over the three different locations of India, which is one of the largest emitters of BC aerosols. The aircraft-based BC observations were conducted from 0.5 to 7 km altitudes using Aethalometer during CAIPEEX (Cloud Aerosol Interaction and Precipitation Enhancement Experiment) Phase I campaigns from June to September 2009. The output of the present study suggests the CAMS reanalysis data significantly underestimated BC mass throughout the vertical profile with an average mass normalized mean bias of greater than −70% at all three locations. Furthermore, the vertical radiative forcing and heating rates of BC were also calculated for both observation and reanalysis data. The output depicts the net forcing due to CAMS simulated BC in all the layers were 1–12 folds lower over all the study regions compared with observed BC aerosols. Likewise, the estimated mean biases in heating rate were in the range of −0.001 to −0.190 K day<sup>−1</sup> for all the vertical layers over the study locations. The possible reasons for these disparities could be poorly constrained emissions, especially aircraft emissions and/or their transformation schemes in aerosol modules. The present study emphasized that the validation of the vertical profile is also an essential factor for better constraints of the BC aerosols in climate models.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106358"},"PeriodicalIF":1.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327102","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
The influence of the solar wind electric and magnetic fields on the latitude and temporal variations of the current density, JZ, of the global electric circuit, with relevance to weather and climate 太阳风电场和磁场对全球电路电流密度 JZ 的纬度和时间变化的影响,以及与天气和气候的关系
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-21 DOI: 10.1016/j.jastp.2024.106355
Brian A. Tinsley
Observations have shown small day-to-day stratiform cloud opacity and atmospheric dynamical responses to variations in the ionosphere-earth current density (JZ). We model the day-to-day and seasonal/bi-decadal changes in the area-integrals of ionospheric potential (Vi) near the magnetic poles due to solar wind electric field inputs. The overhead value of Vi, divided by the local column resistance (R) determines JZ, where the conductivity of the column is the result of ionization by galactic cosmic rays (GCRs) and solar and magnetospheric energetic particle precipitation. These vary with time, due to varying solar wind magnetic field inputs, not only on the day-to-day timescale (e.g., Forbush decreases) but also on the decadal and bi-decadal and century timescales. The GCR and energetic particle inputs vary with latitude, due to filtering of particle energies in the geomagnetic field. We compare area-integrals of the amplitude of the JZ variations due to Vi changes to those due to the R changes, for evaluating their global effectiveness in affecting cloud microphysics and weather and climate changes. The day-to-day and bi-decadal correlated weather and climate variations indicate JZ rather than other solar forcings as mainly responsible for the correlations. The decadal and longer climate responses to space weather are not large; however, understanding them could help improve predictions of future climate change due to greenhouse gases.
观测结果表明,电离层-地球电流密度(JZ)的变化对层状云不透明度和大气动态响应的日变化很小。我们模拟了太阳风电场输入引起的磁极附近电离层电势(Vi)区域积分的逐日和季节/双十年变化。Vi 的开销值除以本地电离层柱电阻(R)决定了 JZ,其中电离层柱的电导率是银河宇宙射线(GCR)以及太阳和磁层高能粒子沉淀电离的结果。由于太阳风磁场输入的变化,这些因素随时间而变化,不仅在逐日时间尺度上(如福布什下降),而且在十年、双十年和世纪时间尺度上也是如此。由于地磁场对粒子能量的过滤作用,全球核磁共振和高能粒子输入量随纬度而变化。我们比较了 Vi 变化和 R 变化引起的 JZ 变幅的面积积分,以评估它们在影响云微观物理和天气及气候变化方面的全球效力。逐日和双十年相关天气和气候变迁表明,JZ 而不是其他太阳作用力是造成相关性的主要原因。对空间天气的十年期和更长气候响应并不大;但是,了解这些响应有助于改进对温室气体导致的未来气候变化的预测。
{"title":"The influence of the solar wind electric and magnetic fields on the latitude and temporal variations of the current density, JZ, of the global electric circuit, with relevance to weather and climate","authors":"Brian A. Tinsley","doi":"10.1016/j.jastp.2024.106355","DOIUrl":"10.1016/j.jastp.2024.106355","url":null,"abstract":"<div><div>Observations have shown small day-to-day stratiform cloud opacity and atmospheric dynamical responses to variations in the ionosphere-earth current density (<em>J</em><sub><em>Z</em></sub><em>).</em> We model the day-to-day and seasonal/bi-decadal changes in the area-integrals of ionospheric potential (<em>V</em><sub><em>i</em></sub>) near the magnetic poles due to solar wind electric field inputs. The overhead value of <em>V</em><sub><em>i</em></sub>, divided by the local column resistance (<em>R</em>) determines <em>J</em><sub><em>Z</em></sub>, where the conductivity of the column is the result of ionization by galactic cosmic rays (GCRs) and solar and magnetospheric energetic particle precipitation. These vary with time, due to varying solar wind magnetic field inputs, not only on the day-to-day timescale (e.g., Forbush decreases) but also on the decadal and bi-decadal and century timescales. The GCR and energetic particle inputs vary with latitude, due to filtering of particle energies in the geomagnetic field. We compare area-integrals of the amplitude of the <em>J</em><sub><em>Z</em></sub> variations due to <em>V</em><sub><em>i</em></sub> changes to those due to the <em>R</em> changes, for evaluating their global effectiveness in affecting cloud microphysics and weather and climate changes. The day-to-day and bi-decadal correlated weather and climate variations indicate <em>J</em><sub><em>Z</em></sub> rather than other solar forcings as mainly responsible for the correlations. The decadal and longer climate responses to space weather are not large; however, understanding them could help improve predictions of future climate change due to greenhouse gases.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106355"},"PeriodicalIF":1.8,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322749","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
Analyzing trend and forecasting of temperature and rainfall in Shimla district of Himachal Pradesh, India using non-parametric and bagging REPTree machine learning approaches 使用非参数和袋式 REPTree 机器学习方法分析和预测印度喜马偕尔邦西姆拉地区的气温和降雨趋势
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-19 DOI: 10.1016/j.jastp.2024.106352
Aastha Sharma, Haroon Sajjad, Tamal Kanti Saha, Md Masroor, Yatendra Sharma, Geeta Kumari
The changing pattern of climate variables has caused extreme weather events and severe disasters, especially in mountainous regions. Such events have a detrimental impact on resources, environment and society. Thus, it has become imperative to examine the trends and forecasts of meteorological variables using a scientific modelling approach. This study investigates temperature and rainfall trends using the modified Mann-Kendall test and Sen's slope estimator between 1980 and 2021. A Bagging-REPTree machine learning model was utilized for forecasting temperature and rainfall trends for the next 30 years (2022–2051) to understand the temporal dynamics in Shimla district of the Indian Himalayan state. The mean absolute percentage error, mean absolute error, root mean squared error and correlation coefficient were determined to assess the effectiveness and precision of the model. The findings revealed that the frequency of intense rainfall in the district has increased during the monsoon season (June–September) from 1980 to 2021. Significant trends were found in annual rainfall, maximum, minimum and mean temperatures while rainfall during the winter, summer and post-monsoon seasons has shown a declining trend. The forecast analysis revealed a significant trend for rainfall during the monsoon season and an increasing trend in the maximum temperature has been observed during the winter and summer seasons. The analysis has provided sufficient evidence of variability and uncertainty in the behavior of meteorological variables. The outcome of the study may help in devising suitable adaptation and mitigation strategies to combat climate change in hilly regions. The methodology adopted in the study may help in the future progression of the research in different geographical regions for trend and climate forecasting.
气候变量模式的变化造成了极端天气事件和严重灾害,尤其是在山区。这些事件对资源、环境和社会产生了有害影响。因此,利用科学建模方法研究气象变量的趋势和预测已成为当务之急。本研究利用改进的 Mann-Kendall 检验法和 Sen's 坡度估计法研究了 1980 年至 2021 年的气温和降雨趋势。利用 Bagging-REPTree 机器学习模型预测了未来 30 年(2022-2051 年)的气温和降雨趋势,以了解印度喜马拉雅邦西姆拉地区的时间动态。确定了平均绝对百分比误差、平均绝对误差、均方根误差和相关系数,以评估模型的有效性和精确性。研究结果表明,从 1980 年到 2021 年,该地区季风季节(6 月至 9 月)的强降雨频率有所增加。年降雨量、最高气温、最低气温和平均气温均呈显著变化趋势,而冬季、夏季和季风后季节的降雨量则呈下降趋势。预测分析表明,季风季节的降雨量呈显著趋势,冬季和夏季的最高气温呈上升趋势。分析充分证明了气象变量行为的可变性和不确定性。研究结果有助于制定适当的适应和减缓战略,以应对丘陵地区的气候变化。研究中采用的方法可能有助于今后在不同地理区域开展趋势和气候预测研究。
{"title":"Analyzing trend and forecasting of temperature and rainfall in Shimla district of Himachal Pradesh, India using non-parametric and bagging REPTree machine learning approaches","authors":"Aastha Sharma,&nbsp;Haroon Sajjad,&nbsp;Tamal Kanti Saha,&nbsp;Md Masroor,&nbsp;Yatendra Sharma,&nbsp;Geeta Kumari","doi":"10.1016/j.jastp.2024.106352","DOIUrl":"10.1016/j.jastp.2024.106352","url":null,"abstract":"<div><div>The changing pattern of climate variables has caused extreme weather events and severe disasters, especially in mountainous regions. Such events have a detrimental impact on resources, environment and society. Thus, it has become imperative to examine the trends and forecasts of meteorological variables using a scientific modelling approach. This study investigates temperature and rainfall trends using the modified Mann-Kendall test and Sen's slope estimator between 1980 and 2021. A Bagging-REPTree machine learning model was utilized for forecasting temperature and rainfall trends for the next 30 years (2022–2051) to understand the temporal dynamics in Shimla district of the Indian Himalayan state. The mean absolute percentage error, mean absolute error, root mean squared error and correlation coefficient were determined to assess the effectiveness and precision of the model. The findings revealed that the frequency of intense rainfall in the district has increased during the monsoon season (June–September) from 1980 to 2021. Significant trends were found in annual rainfall, maximum, minimum and mean temperatures while rainfall during the winter, summer and post-monsoon seasons has shown a declining trend. The forecast analysis revealed a significant trend for rainfall during the monsoon season and an increasing trend in the maximum temperature has been observed during the winter and summer seasons. The analysis has provided sufficient evidence of variability and uncertainty in the behavior of meteorological variables. The outcome of the study may help in devising suitable adaptation and mitigation strategies to combat climate change in hilly regions. The methodology adopted in the study may help in the future progression of the research in different geographical regions for trend and climate forecasting.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106352"},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142318997","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
Main features of the geomagnetic effect of the October 14, 2023 annular solar eclipse in the Americas 2023 年 10 月 14 日美洲日环食地磁效应的主要特征
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-18 DOI: 10.1016/j.jastp.2024.106354
Leonid F. Chernogor, Mariia Yu. Holub, Victor T. Rozumenko

The purpose of this paper is to investigate temporal variations in the northward, X, eastward, Y, and downward, Z, components of the geomagnetic field recorded during the October 14, 2023 annular solar eclipse, which main features include its annularity, the eclipse occurrence from local dawn to local dusk, its magnitude variation from 0.30 to 0.86, and the longest ever-observed path across the mainland of the Americas, covering latitudes from ∼65°N to 12°S. The analysis was made possible due to the data on temporal variations in the northward, X, eastward, Y, and downward, Z, components of the geomagnetic field collected at thirteen International Real-time Magnetic Observatory Network magnetometer stations (https://imag-data.bgs.ac.uk/GIN_V1/GINForms2). The solar eclipse acted to cause non-sinusoidal and quasi-sinusoidal perturbations having temporal durations of 180–240 min in all geomagnetic field components on a global scale (∼8000 km). The X-component experienced the largest perturbations attaining 10–20 nT, and the Z-component underwent the smallest disturbances. The quasi-sinusoidal perturbation amplitude did not exceed 5–6 nT, and the period most often showed variations within 15–40 min. The magnetic effect exhibited a tendency to increase with solar eclipse magnitude, while the magnitude of the effect has been shown to be significantly dependent on geographic coordinates, local time, ionospheric state, and the patterns of ionospheric currents as well. During the solar eclipse, the electron density depletion was estimated to be ∼0.10 to ∼0.40–0.60 when the eclipse obscuration Amax varied from 19% to 82%. The movement of the lunar shadow was accompanied by the generation of atmospheric gravity waves with period of ∼10–80 min and by electron density perturbations with amplitudes of the order of 0.01–0.03. The estimates made on the assumption that the magnetic effect is due to the ionospheric current disruptions show good agreement with the observations.

本文旨在研究 2023 年 10 月 14 日日环食期间记录到的地磁场向北、X、向东、Y 和向下 Z 分量的时间变化,其主要特征包括日环食、日食发生时间为当地黎明至当地黄昏、食甚变化范围为 0.30 至 0.86,以及有史以来观测到的穿越美洲大陆的最长路径,覆盖纬度为北纬 65°至南纬 12°。13 个国际实时磁场观测网络磁强计站 (https://imag-data.bgs.ac.uk/GIN_V1/GINForms2) 收集到的地磁场向北分量 X、向东分量 Y 和向下分量 Z 的时间变化数据使分析成为可能。日食对全球范围内(∼8000 公里)的所有地磁场分量都产生了非正弦和准正弦扰动,时间持续 180-240 分钟。X 分量的扰动最大,达到 10-20 nT,Z 分量的扰动最小。准正弦扰动振幅不超过 5-6 nT,周期多在 15-40 分钟内变化。磁效应随着日食幅度的增大而增强,而效应的大小则与地理坐标、当地时间、电离层状态以及电离层电流模式有很大关系。日食期间,当日食遮蔽率 Amax 在 19% 至 82% 之间变化时,电子密度损耗估计为 ∼0.10 至 ∼0.40-0.60。月影的移动伴随着周期为 10-80 分钟的大气重力波和振幅为 0.01-0.03 的电子密度扰动。假定磁效应是由电离层电流扰动引起的,所做的估计与观测结果十分吻合。
{"title":"Main features of the geomagnetic effect of the October 14, 2023 annular solar eclipse in the Americas","authors":"Leonid F. Chernogor,&nbsp;Mariia Yu. Holub,&nbsp;Victor T. Rozumenko","doi":"10.1016/j.jastp.2024.106354","DOIUrl":"10.1016/j.jastp.2024.106354","url":null,"abstract":"<div><p>The purpose of this paper is to investigate temporal variations in the northward, <em>X</em>, eastward, <em>Y</em>, and downward, Z, components of the geomagnetic field recorded during the October 14, 2023 annular solar eclipse, which main features include its annularity, the eclipse occurrence from local dawn to local dusk, its magnitude variation from 0.30 to 0.86, and the longest ever-observed path across the mainland of the Americas, covering latitudes from ∼65°N to 12°S. The analysis was made possible due to the data on temporal variations in the northward, <em>X</em>, eastward, <em>Y</em>, and downward, Z, components of the geomagnetic field collected at thirteen International Real-time Magnetic Observatory Network magnetometer stations (<span><span>https://imag-data.bgs.ac.uk/GIN_V1/GINForms2</span><svg><path></path></svg></span>). The solar eclipse acted to cause non-sinusoidal and quasi-sinusoidal perturbations having temporal durations of 180–240 min in all geomagnetic field components on a global scale (∼8000 km). The <em>X</em>-component experienced the largest perturbations attaining 10–20 nT, and the <em>Z</em>-component underwent the smallest disturbances. The quasi-sinusoidal perturbation amplitude did not exceed 5–6 nT, and the period most often showed variations within 15–40 min. The magnetic effect exhibited a tendency to increase with solar eclipse magnitude, while the magnitude of the effect has been shown to be significantly dependent on geographic coordinates, local time, ionospheric state, and the patterns of ionospheric currents as well. During the solar eclipse, the electron density depletion was estimated to be ∼0.10 to ∼0.40–0.60 when the eclipse obscuration <em>A</em><sub><em>max</em></sub> varied from 19% to 82%. The movement of the lunar shadow was accompanied by the generation of atmospheric gravity waves with period of ∼10–80 min and by electron density perturbations with amplitudes of the order of 0.01–0.03. The estimates made on the assumption that the magnetic effect is due to the ionospheric current disruptions show good agreement with the observations.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106354"},"PeriodicalIF":1.8,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142273890","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
A comprehensive evaluation of lightning location accuracy using a weighted gridding method 使用加权网格法全面评估闪电定位精度
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-17 DOI: 10.1016/j.jastp.2024.106342
Lin Song , Qingda Li , Jun Yang , Qilin Zhang , Jie Li , Shudong Wang , Yuqing Zhong , Zhiren Zhou , Meng Zheng
For the newly built very low-frequency long-range lightning location network (VLF-LLN) in China based on the equivalent propagation velocity method, we have evaluated the probability of deviation distance between the locations results and the reference points by using a weighted gridding method, and have drawn some conclusions. (1) By analyzing the effects of different numbers and configurations of stations on the location deviations, it is found that when the number of participating stations increase, the location deviation relatively decreases, and the numbers and configurations of participating stations has much more effect on the probability of location deviation of the lightning flashes outside the network than those in the network; (2) We statistically analyzed the location deviation for each grid of the network by using a weighted gridding method. The deviation probability using 11-station synchronization as a reference is similar to that for 13-station synchronization per grid. Assuming that the deviation distance is less than 3–5 km, the average location results are almost unchanged when the station number exceeds 7 or 8; (3) Comparing with the Advanced Direction and Time-of-Arrival Detecting network (ADTD), our VLF-LLN has an average deviation value of 3.47 km and a median value of 1.81 km for 63767 lightning flashes, and 90% samples have the location deviation less than 8 km and 54% have the location deviation less than 2 km.
针对我国新建的基于等效传播速度法的甚低频长距离雷电定位网(VLF-LLN),采用加权网格法对定位结果与参考点之间的偏差距离概率进行了评估,并得出了一些结论。(1)通过分析不同台站数量和配置对位置偏差的影响,发现当参与台站数量增加时,位置偏差相对减小,且参与台站数量和配置对网外雷闪位置偏差概率的影响远大于网内雷闪位置偏差概率;(2)采用加权网格法统计分析了网内各网格的位置偏差。以 11 站同步为参考的偏差概率与每个网格 13 站同步的偏差概率相似。假设偏差距离小于 3-5 千米,当站点数量超过 7 或 8 个时,平均定位结果几乎没有变化;(3)与高级方向和到达时间检测网络(ADTD)相比,我们的 VLF-LLN 对 63767 次闪电的平均偏差值为 3.47 千米,中值为 1.81 千米,90% 的样本的定位偏差小于 8 千米,54% 的样本的定位偏差小于 2 千米。
{"title":"A comprehensive evaluation of lightning location accuracy using a weighted gridding method","authors":"Lin Song ,&nbsp;Qingda Li ,&nbsp;Jun Yang ,&nbsp;Qilin Zhang ,&nbsp;Jie Li ,&nbsp;Shudong Wang ,&nbsp;Yuqing Zhong ,&nbsp;Zhiren Zhou ,&nbsp;Meng Zheng","doi":"10.1016/j.jastp.2024.106342","DOIUrl":"10.1016/j.jastp.2024.106342","url":null,"abstract":"<div><div>For the newly built very low-frequency long-range lightning location network (VLF-LLN) in China based on the equivalent propagation velocity method, we have evaluated the probability of deviation distance between the locations results and the reference points by using a weighted gridding method, and have drawn some conclusions. (1) By analyzing the effects of different numbers and configurations of stations on the location deviations, it is found that when the number of participating stations increase, the location deviation relatively decreases, and the numbers and configurations of participating stations has much more effect on the probability of location deviation of the lightning flashes outside the network than those in the network; (2) We statistically analyzed the location deviation for each grid of the network by using a weighted gridding method. The deviation probability using 11-station synchronization as a reference is similar to that for 13-station synchronization per grid. Assuming that the deviation distance is less than 3–5 km, the average location results are almost unchanged when the station number exceeds 7 or 8; (3) Comparing with the Advanced Direction and Time-of-Arrival Detecting network (ADTD), our VLF-LLN has an average deviation value of 3.47 km and a median value of 1.81 km for 63767 lightning flashes, and 90% samples have the location deviation less than 8 km and 54% have the location deviation less than 2 km.</div></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"265 ","pages":"Article 106342"},"PeriodicalIF":1.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142326365","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
A case study on the dust storm that occurred on March 13–18, 2022, over the Algerian Sahara, using satellite remote sensing 利用卫星遥感技术对 2022 年 3 月 13-18 日发生在阿尔及利亚撒哈拉沙漠上空的沙尘暴进行案例研究
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-14 DOI: 10.1016/j.jastp.2024.106345
Riad Guehaz , Venkataraman Sivakumar , Nkanyiso Mbatha

This study investigates the dynamics of a significant dust storm that occurred in Algeria in March 2022, employing data derived from the Sentinel-5P and CALIPSO satellite instruments. We examine the Aerosol Absorbing Index (AAI) to detect n absorbing aerosols, with a focus on desert dust, and analyze the attenuation coefficient. Additionally, we employ the HYSPLIT trajectory analyze to study dust transport and MERRA-2 to examine wind patterns wind. The key findings unveil a detailed trajectory of a prominent dust storm in Algeria in March 2022. The Aerosol Absorbing Index (AAI) effectively identifies absorbing aerosols, particularly desert dust, through thorough analyses of dust trajectory and wind patterns; augmenting these findings, CALIPSO satellite data has provided a detailed vertical profile of aerosols within the dust plume, emphasizing spatial and altitudinal extents. This research significantly contributes to advancing scientific discussions on atmospheric dynamics in arid regions and enhances our understanding and forecasting capabilities related to Saharan dust storm initiation and trajectory.

本研究利用 Sentinel-5P 和 CALIPSO 卫星仪器获得的数据,对 2022 年 3 月在阿尔及利亚发生的重大沙尘暴的动态进行了调查。我们研究了气溶胶吸收指数(AAI),以探测 n 种吸收气溶胶,重点是沙漠尘埃,并分析了衰减系数。此外,我们还利用 HYSPLIT 轨迹分析来研究沙尘的传输,并利用 MERRA-2 来研究风的模式。主要研究结果揭示了 2022 年 3 月阿尔及利亚一场突出沙尘暴的详细轨迹。气溶胶吸收指数(AAI)通过对沙尘轨迹和风型的全面分析,有效地识别了吸收性气溶胶,尤其是沙漠沙尘;CALIPSO卫星数据提供了沙尘羽流中气溶胶的详细垂直剖面图,强调了空间和高度范围,从而进一步丰富了这些发现。这项研究极大地促进了对干旱地区大气动力学的科学讨论,并增强了我们对撒哈拉沙尘暴的起因和轨迹的了解和预测能力。
{"title":"A case study on the dust storm that occurred on March 13–18, 2022, over the Algerian Sahara, using satellite remote sensing","authors":"Riad Guehaz ,&nbsp;Venkataraman Sivakumar ,&nbsp;Nkanyiso Mbatha","doi":"10.1016/j.jastp.2024.106345","DOIUrl":"10.1016/j.jastp.2024.106345","url":null,"abstract":"<div><p>This study investigates the dynamics of a significant dust storm that occurred in Algeria in March 2022, employing data derived from the Sentinel-5P and CALIPSO satellite instruments. We examine the Aerosol Absorbing Index (AAI) to detect n absorbing aerosols, with a focus on desert dust, and analyze the attenuation coefficient. Additionally, we employ the HYSPLIT trajectory analyze to study dust transport and MERRA-2 to examine wind patterns wind. The key findings unveil a detailed trajectory of a prominent dust storm in Algeria in March 2022. The Aerosol Absorbing Index (AAI) effectively identifies absorbing aerosols, particularly desert dust, through thorough analyses of dust trajectory and wind patterns; augmenting these findings, CALIPSO satellite data has provided a detailed vertical profile of aerosols within the dust plume, emphasizing spatial and altitudinal extents. This research significantly contributes to advancing scientific discussions on atmospheric dynamics in arid regions and enhances our understanding and forecasting capabilities related to Saharan dust storm initiation and trajectory.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"264 ","pages":"Article 106345"},"PeriodicalIF":1.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142242335","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
Consistency of climatic changes at different time scales in Central England and Greenland 英格兰中部和格陵兰岛不同时间尺度气候变化的一致性
IF 1.8 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Pub Date : 2024-09-13 DOI: 10.1016/j.jastp.2024.106343
Rodion Stepanov , Dmitry Sokoloff , Peter Frick

Characteristic variations in the Greenland isotope temperature data over the last 1000 years and in the meteorological temperature measurements collected from Central England during the past four centuries have been analyzed. We take advantage of the continuous wavelet transform to analyze the simultaneous occurrence of temperature variations of different time scales. We assess the extent to which these phenomena can be compared when examining two different northern hemisphere locations at different time scales. Among the long-term variations, we focus on the cooling at the turn of the 18th century, which occurred slightly later in Greenland than in central England, and the warming observed at present. On the short time scale, the range under study is limited to times of the order of 5-10 years. It has been found that it is on these scales that temperature variations in the two locations are relatively consistent, with a cross-correlation coefficient as high as 0.6 for timescales of the order of 9 years. The main solar activity cycle also falls within the interval of significant correlations. It is shown that despite the absence of direct correlation between temperature and solar activity, the time dependence of the wavelet cross-correlation coefficient of the two temperature series on the scale of 11 years reproduces the long-term variations of solar activity.

我们分析了过去 1000 年格陵兰岛同位素温度数据和过去四个世纪英格兰中部气象温度测量数据的特征变化。我们利用连续小波变换分析了不同时间尺度上同时出现的温度变化。在研究北半球两个不同地点不同时间尺度的气温变化时,我们评估了这些现象的可比较程度。在长期变化中,我们重点关注 18 世纪之交的降温(格陵兰岛的降温比英格兰中部稍晚)和目前观测到的升温。在短时间尺度上,研究范围仅限于 5-10 年左右。研究发现,正是在这些时间尺度上,两地的气温变化相对一致,在 9 年左右的时间尺度上,交叉相关系数高达 0.6。主要太阳活动周期也在显著相关区间内。研究表明,尽管气温与太阳活动之间没有直接的相关性,但两个气温序列的小波交叉相关系数在 11 年尺度上的时间依赖性再现了太阳活动的长期变化。
{"title":"Consistency of climatic changes at different time scales in Central England and Greenland","authors":"Rodion Stepanov ,&nbsp;Dmitry Sokoloff ,&nbsp;Peter Frick","doi":"10.1016/j.jastp.2024.106343","DOIUrl":"10.1016/j.jastp.2024.106343","url":null,"abstract":"<div><p>Characteristic variations in the Greenland isotope temperature data over the last 1000 years and in the meteorological temperature measurements collected from Central England during the past four centuries have been analyzed. We take advantage of the continuous wavelet transform to analyze the simultaneous occurrence of temperature variations of different time scales. We assess the extent to which these phenomena can be compared when examining two different northern hemisphere locations at different time scales. Among the long-term variations, we focus on the cooling at the turn of the 18th century, which occurred slightly later in Greenland than in central England, and the warming observed at present. On the short time scale, the range under study is limited to times of the order of 5-10 years. It has been found that it is on these scales that temperature variations in the two locations are relatively consistent, with a cross-correlation coefficient as high as 0.6 for timescales of the order of 9 years. The main solar activity cycle also falls within the interval of significant correlations. It is shown that despite the absence of direct correlation between temperature and solar activity, the time dependence of the wavelet cross-correlation coefficient of the two temperature series on the scale of 11 years reproduces the long-term variations of solar activity.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":"264 ","pages":"Article 106343"},"PeriodicalIF":1.8,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142242336","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
期刊
Journal of Atmospheric and Solar-Terrestrial Physics
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1