Journal of Atmospheric and Solar-Terrestrial Physics最新文献_第2页

PAOFCDN: A novel method for predictive analysis of solar irradiance PAOFCDN：预测分析太阳辐照度的新方法

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-22 DOI: 10.1016/j.jastp.2024.106376

Sana Mujeeb

Solar photovoltaic power is the most feasible Renewable Energy Source (RES) for Pakistan, due to ample sunlight availability throughout the year. Since solar photovoltaic power is primarily dependent on solar irradiance, forecasting of solar irradiance is essential for reliable, secure and effective incorporation of solar photovoltaic power in power systems. Considering the importance of solar irradiance forecasting, in this study, predictive analysis of Islamabad’s solar irradiance is performed by using a novel proposed model named as Pelican Algorithm-based Optimized Fully-Connected Deep Network (PAOFCDN). The initial weights of Fully-Connected Deep Network (FCDN) are optimized through an effective optimization technique known as Pelican optimization. The accuracy of the optimized network PAOFCDN is enhanced many fold as compared to the FCDN network trained with randomly initialized weights. The inherent issue of poor generalization in FCDN is also resolved by optimization. The superior performance of PAOFCDN is evident from its comparative evaluation with existing benchmark methods, i.e., Long Short-Term Memory (LSTM), Support Vector Regression (SVR), Least Square Boosting (LSBoost) and standard FCDN. PAOFCDN achieves the least Normalized Root Mean Square Error (NRMSE) of 0.0503 as compared to 0.1179 of LSTM, 0.1256 of FCDN, and 0.2992 of SVR and LSBoost. The proposed model is applied to three real-world solar irradiance datasets having different resolutions of 10-minutes, hourly and daily. This study took the initiative of performing predictions on three datasets having multiple resolutions in perspective of south asia.

太阳能光伏发电是巴基斯坦最可行的可再生能源 (RES)，因为巴基斯坦全年都有充足的日照。由于太阳能光伏发电主要依赖于太阳辐照度，因此要将太阳能光伏发电可靠、安全、有效地纳入电力系统，就必须对太阳辐照度进行预测。考虑到太阳辐照度预测的重要性，在本研究中，通过使用一种名为 "基于鹈鹕算法的优化全连接深度网络（PAOFCDN）"的新模型，对伊斯兰堡的太阳辐照度进行了预测分析。全连接深度网络（FCDN）的初始权重是通过一种名为鹈鹕优化的有效优化技术进行优化的。与使用随机初始化权重训练的 FCDN 网络相比，经过优化的 PAOFCDN 网络的准确性提高了许多倍。FCDN 固有的泛化能力差的问题也通过优化得到了解决。PAOFCDN 与现有基准方法（即长短期记忆 (LSTM)、支持向量回归 (SVR)、最小平方提升 (LSBoost) 和标准 FCDN）的比较评估表明，PAOFCDN 性能优越。与 LSTM 的 0.1179、FCDN 的 0.1256 以及 SVR 和 LSBoost 的 0.2992 相比，PAOFCDN 的归一化均方根误差（NRMSE）最小，为 0.0503。提出的模型被应用于三个真实世界的太阳辐照度数据集，这些数据集的分辨率各不相同，分别为 10 分钟、每小时和每天。本研究以南亚地区为视角，对三个具有不同分辨率的数据集进行了预测。

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引用次数: 0

On the low-latitude ionospheric irregularities under geomagnetically active and quiet conditions using NavIC observables: A spectral analysis approach 利用 NavIC 观测数据研究地磁活跃和安静条件下的低纬度电离层不规则性：光谱分析方法

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-22 DOI: 10.1016/j.jastp.2024.106369

Sumanjit Chakraborty , Abhirup Datta

Ionospheric irregularities and associated scintillations under geomagnetically active/quiet conditions have detrimental effects on the reliability and performance of space- and ground-based navigation satellite systems, especially over the low-latitude region. The current work investigates the low-latitude ionospheric irregularities using the phase screen theory and the corresponding temporal Power Spectral Density (PSD) analysis to present an estimate of the outer irregularity scale sizes over these locations. The study uses simultaneous L5 signal C/N

_{o}

observations of NavIC (a set of GEO and GSO navigation satellite systems) near the northern crest of EIA (Indore: 22.52

^{\circ}

N, 75.92

^{\circ}

E, dip: 32.23

^{\circ}

N) and in between the crest and the dip equator (Hyderabad: 17.42

^{\circ}

N, 78.55

^{\circ}

E, dip: 21.69

^{\circ}

N). The study period (2017–2018) covers disturbed and quiet-time conditions in the declining phase of the solar cycle 24. The PSD analysis brings forward the presence of irregularities, of the order of a few hundred meters during weak-to-moderate and quiet-time conditions and up to a few km during the strong event, over both locations. The ROTI values validate the presence of such structures in the Indian region. Furthermore, only for the strong event, a time delay of scintillation occurrence over Indore, with values of 36 min and 50 min for NavIC satellites (PRNs) 5 and 6, respectively, from scintillation occurrence at Hyderabad is observed, suggesting a poleward evolution of irregularity structures. Further observations show a westward propagation of these structures on this day. This study brings forward the advantage of utilizing continuous data from the GEO and GSO satellite systems in understanding the evolution and propagation of the ionospheric irregularities over the low-latitude region.

地磁活跃/安静条件下的电离层不规则现象和相关闪烁对空间和地面导航卫星系统的可靠性和性能有不利影响，特别是在低纬度地区。目前的工作利用相屏理论和相应的时间功率谱密度分析对低纬度电离层不规则现象进行了研究，提出了对这些地点外部不规则现象规模大小的估计。该研究使用了在 EIA 北部波峰附近（印多尔：22.52∘N，75.92∘E，倾角：32.23∘N）和波峰与倾角赤道之间（海得拉巴：17.42∘N，78.55∘E，倾角：21.69∘N）的 NavIC（一组地球同步轨道和地球同步轨道导航卫星系统）的 L5 信号 C/No 同步观测。研究时段（2017-2018 年）涵盖了太阳周期 24 递减阶段的扰动和静止状态。PSD 分析表明，这两个地点存在不规则现象，在弱至中等强度和静止期间为几百米，在强事件期间可达几千米。ROTI 值验证了印度地区存在此类结构。此外，仅在强事件中，NavIC 卫星（PRNs）5 号和 6 号在印多尔上空发生闪烁的时间与海德拉巴发生闪烁的时间分别延迟了 36 分钟和 50 分钟，这表明不规则结构是向极地演化的。进一步的观测表明，这些结构在这一天向西传播。这项研究提出了利用地球同步轨道和地球静止轨道卫星系统的连续数据来了解低纬度地区电离层不规则结构的演变和传播的优势。

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引用次数: 0

Impact of aerosols on atmospheric electrification over East and West Africa 气溶胶对东非和西非大气电气化的影响

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-22 DOI: 10.1016/j.jastp.2024.106375

B. Mmame , C. Ngongondo

Studies have shown that atmospheric aerosols can modify cloud microphysics. The influence of atmospheric aerosols on mechanisms that lead to generation of lightning is very complex and not fully understood. Recent studies have also revealed that, west Africa has high concentration of atmospheric aerosols due to localized wind which diverge from Sahara desert to this area. This study investigates the impact of atmospheric aerosols on lightning flash rate over east and west Africa by utilizing aerosol optical depth (AOD) from Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) reanalysis data, convective available potential energy (CAPE), potential temperature, surface relative humidity, clouds and lightning flash rate. Pearson correlation and partial correlation have been applied between lightning flash rate and AOD, humidity, clouds, CAPE as well as potential temperature. Quantitative results show that there is a strong positive correlation (

\sim

0.75) between lightning flash rate and aerosols under low concentration of aerosols (AOD

\leq

0.6) due to aerosol microphysics effect. In the presence of high aerosol concentration (AOD

>

0.6), the correlation coefficient between lightning flash rate and aerosols is somehow weak (

\sim

0.45) due to decrease in the number of ice particles as well as radiation effect of aerosols. However, the correlation coefficient between lightning flash rate and CAPE, clouds and potential temperature are all positive under both high and low concentration of atmospheric aerosols.

研究表明，大气气溶胶可以改变云的微物理学。大气气溶胶对导致闪电产生的机制的影响非常复杂，尚未完全清楚。最近的研究还表明，由于从撒哈拉沙漠分流到该地区的局部风，西非的大气气溶胶浓度很高。本研究利用现代研究和应用回顾分析第 2 版（MERRA-2）再分析数据中的气溶胶光学深度（AOD）、对流可用势能（CAPE）、势温、表面相对湿度、云层和闪电率，研究了大气气溶胶对非洲东部和西部闪电率的影响。雷闪率与 AOD、湿度、云、CAPE 和位势温度之间采用了皮尔逊相关性和部分相关性分析。定量结果表明，由于气溶胶微物理效应，在气溶胶浓度较低（AOD ≤ 0.6）的情况下，雷闪率与气溶胶之间存在较强的正相关性（∼0.75）。在气溶胶浓度较高（AOD > 0.6）的情况下，由于冰颗粒数量的减少以及气溶胶的辐射效应，闪电闪烁率与气溶胶之间的相关系数较弱（∼0.45）。然而，在大气气溶胶浓度较高和较低的情况下，雷闪率与 CAPE、云和势温之间的相关系数均为正值。

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引用次数: 0

Changes in turbulent processes caused by atmospheric gravity waves from troposphere 对流层大气重力波引起的湍流过程变化

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-22 DOI: 10.1016/j.jastp.2024.106364

Liudmyla Kozak , Istvan Ballai , Viktor Fedun , Elena A. Kronberg , Aljona Bloecker , Bohdan Petrenko

We have determined that changes in temperature and wind speed recorded in the Earth‘s upper atmosphere above tropospheric sources (hurricanes) can be explained by the propagation of atmospheric gravity waves (AGW). We carried out modeling of the propagation of AGW with a period of 65 min and

k_{x} = 1 0^{- 5}

m⁻¹ using multi-layer methods in a non-homogeneous, non-isothermal atmosphere, taking into account viscosity and thermal conductivity. We obtained that disturbances in the horizontal component of the velocity are five times greater than the increase in the vertical component of the velocity, and temperature changes can reach 30 K. We should note that the disturbances of temperature and pressure as a result of AGW spreading are superimposed onto the usual view of changes of pressure and temperature with the altitude and reach the maximum amplitude in the range from 90 to 100 km. The obtained changes in the temperature of the upper atmosphere and the velocity with height as a result of the presence of AGW made it possible to estimate the values of the coefficients of turbulent viscosity and thermal conductivity in the upper atmosphere of the Earth above tropospheric energy sources. Intensification of turbulent processes was recorded in the range of altitudes from 75 to 100 km.

我们已经确定，在对流层源（飓风）上方的地球高层大气中记录到的温度和风速变化可以用大气重力波（AGW）的传播来解释。我们使用多层方法在非均质、非等温大气中对周期为 65 分钟、kx=10-5 m-1 的 AGW 传播进行了建模，并考虑了粘度和导热性。我们得到的结果是，速度水平分量的扰动比速度垂直分量的增加大五倍，温度变化可达 30 K。我们应该注意到，AGW 传播导致的温度和压力扰动与压力和温度随高度变化的通常观点相叠加，并在 90 至 100 千米范围内达到最大振幅。由于存在 AGW，高层大气温度和速度随高度的变化得以估算对流层能量源上方地球高层大气的湍流粘度和热传导系数的值。在 75 至 100 公里的高度范围内记录到湍流过程的加剧。

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引用次数: 0

Dynamical complexity and multifractal analysis of geomagnetic activities at high temporal scales over three solar cycles 三个太阳周期高时间尺度地磁活动的动态复杂性和多分形分析

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-21 DOI: 10.1016/j.jastp.2024.106380

Samuel Ogunjo , Joshua Akinsusi , Babatunde Rabiu , Ibiyinka Fuwape

Activities in geospace occur at different time scales. Understanding geomagnetic activity at high temporal scales will give insight into fast dynamics in geospace. This study aims to investigate dynamical complexities in geomagnetic activities at a high temporal scale across three solar cycles. Geomagnetic activities, as represented by 5-min SYM-H data, were considered in this study over three solar cycles (22–24) from 1986 to 2019. Chaos analysis using sample entropy, Lyapunov exponent, and correlation dimension indicates that the geomagnetic activities are driven by intrinsic complex and chaotic processes. Positive Lyapunov exponent values between 0.13 and 0.18, 0.15–0.18, and 0.16–0.19 were obtained for solar cycles 22, 23, and 24 respectively. Furthermore, geomagnetic activities were also found to have multifractal structures driven by high fractal exponents with fine structures. A positive relationship was obtained between the annual mean values of SYM-H and the degree of complexity. It is concluded that geomagnetic activities have a short prediction horizon.

地球空间的活动发生在不同的时间尺度上。了解高时间尺度的地磁活动将有助于深入了解地球空间的快速动力学。本研究旨在研究三个太阳周期中高时间尺度地磁活动的动态复杂性。本研究考虑了从 1986 年到 2019 年三个太阳周期（22-24）中以 5 分钟 SYM-H 数据为代表的地磁活动。利用样本熵、Lyapunov 指数和相关维度进行的混沌分析表明，地磁活动是由内在的复杂混沌过程驱动的。太阳周期 22、23 和 24 的李亚普诺夫指数分别为 0.13 至 0.18、0.15 至 0.18 和 0.16 至 0.19。此外，研究还发现地磁活动具有多分形结构，由具有精细结构的高分形指数驱动。SYM-H 的年平均值与复杂程度之间存在正相关关系。结论是地磁活动的预测范围较短。

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引用次数: 0

Aspect sensitivity measurement of backscattering radar echoes from 205 MHz Stratosphere–Troposphere radar at a tropical coastal station 在热带海岸站测量 205 MHz 平流层-对流层雷达反向散射雷达回波的高宽比灵敏度

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-19 DOI: 10.1016/j.jastp.2024.106367

Dhanya R. , Anju Pradeep , Rakesh V. , Abhilash S. , K. Mohankumar , Sivan C. , Rejoy Rebello , Prabhath H. Kurup

Aspect sensitivity in VHF radar refers to the extent to which the power and spectrum width of echoes vary with changes in the zenith angle, which is related to the backscattering process. The scattering of clear air signals is primarily caused by Fresnel reflection, anisotropic scattering, and isotropic scattering. The aspect sensitivity and accuracy of moment and wind estimation in clear air radars are influenced by the beam width, beam pointing angle from zenith, and atmospheric conditions. This study proposes a method to determine the sensitivity of the recently developed Stratosphere–Troposphere (ST) wind profile Radar in Cochin, India (10.04°N, 76.33°E). The radar operates at a distinct frequency of 205 MHz in the far VHF band. The experiment is conducted at an altitude of 5 to 20 km above the ground by adjusting the beam’s orientation with a resolution of 2°in both the east–west and north-south directions. The estimation of wind components is subject to uncertainty due to the varying aspect angles caused by the distinct dispersion properties in this height range. The study found that power variance is lowest between 6 and 12 km in both north-south and east–west directions, while daily fluctuations in aspect-sensitive echoes complicate wind component estimation. Correlation length (

ζ

) ranges from 0.5 to 15 m, indicating various air scattering processes. Notably,

θ_{s}

is smaller near the zenith and increases with tilt angles, exceeding 20°up to 14 km before declining at higher altitudes, indicating significant anisotropy at elevated levels. The wide range of R factor values (0.1 to 0.9) across different heights causes significant ambiguity in wind estimation. In this study, the impact of various aspect sensitivity parameters on wind estimation on days with clear air has been analyzed.

甚高频雷达的频谱灵敏度是指回波的功率和频谱宽度随天顶角变化而变化的程度，这与后向散射过程有关。晴空信号的散射主要由菲涅尔反射、各向异性散射和各向同性散射引起。晴空雷达的方位灵敏度和时刻及风估算精度受波束宽度、波束与天顶的指向角和大气条件的影响。本研究提出了一种方法来确定最近在印度科钦（北纬 10.04°，东经 76.33°）开发的平流层-对流层（ST）风廓线雷达的灵敏度。该雷达的工作频率为 205 兆赫，属于远甚高频波段。实验在离地面 5 至 20 千米的高度进行，通过调整波束的方向，东西和南北方向的分辨率均为 2°。在这一高度范围内，由于不同的频散特性造成了不同的纵横角，因此对风分量的估算存在不确定性。研究发现，南北向和东西向 6 至 12 千米范围内的功率方差最小，而纵横向敏感回波的日波动使风分量估算复杂化。相关长度（ζ）从 0.5 米到 15 米不等，表明存在各种空气散射过程。值得注意的是，θs 在天顶附近较小，并随倾斜角的增大而增大，在 14 千米以内超过 20°，然后在更高的高度下降，这表明在高空有明显的各向异性。不同高度的 R 因子值范围很广（0.1 至 0.9），导致风力估算非常模糊。在这项研究中，分析了各种高程灵敏度参数对晴朗天气风力估算的影响。

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引用次数: 0

Differential responses of total ozone content to solar activity parameters at two Saudi Arabian locations 沙特阿拉伯两地臭氧总量对太阳活动参数的不同反应

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-18 DOI: 10.1016/j.jastp.2024.106379

Abdullrahman Maghrabi, Mayson Alghamdi

This study examines the correlations between Total Ozone Content (TOC) at two locations in Saudi Arabia—Abha and Jeddah—and various solar activity indicators (sunspot numbers, solar radio flux) and cosmic rays, using data spanning from 1979 to 2023. The research employs correlation analyses and spectral techniques, such as Fast Fourier Transform and wavelet analysis, to explore these relationships.

The results reveal significant non-zero correlations between changes in TOC at both Saudi sites and the studied solar activity indicators and cosmic rays, with these correlations varying in strength and significance across different solar cycles and seasons.

Spectral analysis suggests the presence of several periodicities in the TOC data from both sites, including cycles of 3.9 years, 2.63 years, 1.65 years, 1.1–1.2 years, 325 days (∼0.88 years), 285–293 days (∼0.78–0.80 years), 273 days (∼0.75 years), 249-232 days (∼0.68 years), and 202-188 days (∼0.52 years). Notable shared periodicities between TOC and solar activity and cosmic rays data include ∼2.6 years, 3.8–3.9 years, 1.56 years, 325 days, 273 days, and 166 days.

The findings from both correlation and spectral analyses suggest a potential connection between variations in TOC and solar activity at the specific locations studied. This aligns with previous research indicating that increased UV radiation during periods of high solar activity enhances ozone production, particularly at lower latitudes, and that increased magnetic activity reduces the influx of cosmic rays into the heliosphere, impacting atmospheric ionization.

本研究利用从 1979 年到 2023 年的数据，研究了沙特阿拉伯两个地点--阿布哈和吉达--的臭氧总含量（TOC）与各种太阳活动指标（太阳黑子数、太阳射电通量）和宇宙射线之间的相关性。研究采用了相关性分析和光谱技术（如快速傅立叶变换和小波分析）来探索这些关系。研究结果表明，沙特两个站点的总有机碳变化与所研究的太阳活动指标和宇宙射线之间存在显著的非零相关性，这些相关性在不同太阳周期和季节的强度和重要性各不相同。频谱分析表明，两个观测点的 TOC 数据存在若干周期性变化，包括 3.9 年、2.63 年、1.65 年、1.1-1.2年、325天（∼0.88年）、285-293天（∼0.78-0.80年）、273天（∼0.75年）、249-232天（∼0.68年）和202-188天（∼0.52年）。TOC与太阳活动和宇宙射线数据之间显著的共同周期包括：2.6年、3.8-3.9年、1.56年、325天、273天和166天。这与之前的研究结果一致，即太阳活动频繁时紫外线辐射增加会促进臭氧生成，尤其是在低纬度地区；磁活动增加会减少宇宙射线流入日光层，从而影响大气电离。

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引用次数: 0

Electron-ion model of ball and bead lightning 球状和珠状闪电的电子-离子模型

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-17 DOI: 10.1016/j.jastp.2024.106374

Sergey G. Fedosin

Based on the electron-ion model, parameters of ball and bead lightning are calculated. The model allows us to estimate maximum size of ball lightning, its energy content, electric charge and magnetic field, to determine equilibrium conditions between positively charged ions located inside and outer shell containing rapidly moving electrons. An explanation is given to the fact that shells are observed inside ball lightning that differ from each other in color of glow. The model describes structure of not only ball lightning, but also bead lightning. The long-term stability of bead lightning is associated with the balance of neighboring beads under action of magnetic force of their attraction and electric force of repulsion, which exceed in magnitude the force of wind pressure.

根据电子-离子模型，计算了球状闪电和珠状闪电的参数。通过该模型，我们可以估算球状闪电的最大尺寸、能量含量、电荷和磁场，确定位于内部的带正电离子与包含快速移动电子的外壳之间的平衡条件。该模型解释了为什么在球状闪电内部会观察到不同颜色的外壳。该模型不仅描述了球状闪电的结构，还描述了珠状闪电的结构。珠状闪电的长期稳定性与相邻珠子在磁力吸引和电力排斥作用下的平衡有关，而磁力和电力排斥的大小超过了风压的力量。

引用次数: 0

Construction of global IGS-3D electron density (Ne) model by deep learning 通过深度学习构建全球 IGS-3D 电子密度（Ne）模型

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-16 DOI: 10.1016/j.jastp.2024.106370

Eun-Young Ji , Yong-Jae Moon , Young-Sil Kwak , Kangwoo Yi , Jeong-Heon Kim

In this study, we construct a global IGS-3D N_e model that generates global 3-D electron density (N_e) from International Global Navigation Satellite Systems (GNSS) Service (IGS) total electron content (TEC) data through deep learning. As a first step towards this, we make a model to generate a vertical electron density profile from a TEC value using Multi-Layer Perceptron (MLP). In this process, we use the vertical electron density profiles and the corresponding TEC values of the IRI-2016 model from 2001 to 2008 for training, 2009 and 2014 for validation, and 2010 to 2013 for a test. The next step is to generate global IGS electron density profiles using the global IGS TECs as input data for the model, which is called the global IGS-3D N_e model. We evaluate the IGS-3D N_e model by comparing the electron density profiles from the incoherent scatter radars (ISRs) at three stations with the IGS-3D N_e model from 2010 to 2013. The evaluation shows that the electron density profiles from the IGS-3D N_e model are closer to the ISR data than those of the IRI model, especially at high latitudes. The IGS-3D N_e model shows that the averaged root mean square error (RMSE) values between IGS and ISR electron density profiles are 0.37 log(m⁻³), 0.22 log(m⁻³), and 0.34 log(m⁻³) for all test datasets at Jicamarca, Millstone Hill, and EISCAT stations, respectively. These results suggest that our method has sufficient potential to enhance the ability to predict global electron density profiles.

在本研究中，我们构建了一个全球 IGS-3D Ne 模型，通过深度学习从国际全球导航卫星系统（GNSS）服务（IGS）总电子含量（TEC）数据生成全球三维电子密度（Ne）。作为实现这一目标的第一步，我们利用多层感知器（MLP）建立了一个模型，从 TEC 值生成垂直电子密度剖面。在此过程中，我们使用 2001 年至 2008 年 IRI-2016 模型的垂直电子密度剖面和相应的 TEC 值作为训练，2009 年和 2014 年作为验证，2010 年至 2013 年作为测试。下一步是利用全球IGS TEC值作为模型的输入数据，生成全球IGS电子密度剖面，这就是全球IGS-3D Ne模型。我们通过比较2010年至2013年三个站点非相干散射雷达（ISR）的电子密度剖面与IGS-3D Ne模型，对IGS-3D Ne模型进行了评估。评估结果表明，IGS-3D Ne模式的电子密度剖面比IRI模式更接近ISR数据，尤其是在高纬度地区。IGS-3D Ne模型显示，在Jicamarca、Millstone Hill和EISCAT站点的所有测试数据集上，IGS和ISR电子密度剖面的平均均方根误差（RMSE）值分别为0.37 log(m-3)、0.22 log(m-3)和0.34 log(m-3)。这些结果表明，我们的方法有足够的潜力来提高预测全球电子密度剖面的能力。

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引用次数: 0

Mediaeval Korean aurora and flood records and solar activity cycle of ∼200 yr 韩国中世纪的极光和洪水记录与 200 年的太阳活动周期

IF 1.8 4区地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS

Journal of Atmospheric and Solar-Terrestrial Physics

Pub Date : 2024-10-16 DOI: 10.1016/j.jastp.2024.106373

Kim Jik Su , Kim Chol Jun , Kim Jong Myong

Previous investigation of mediaeval Korean naked-eye sunspot observations has shown the existence of the solar activity cycle of ∼200yr. We examined other mediaeval Korean records of auroral phenomena and floods, and reconfirm the long-term periodicity of ∼200yr. This finding, together with the result of naked-eye sunspot records investigation allows us to confirm again the evidence of the long-term cycle ∼200yr in solar activity.

以前对韩国中世纪裸眼太阳黑子观测的研究表明，太阳活动周期为 200 年。我们研究了韩国中世纪有关极光现象和洪水的其他记录，再次确认了 200 年的长期周期性。这一发现，加上裸眼太阳黑子记录的调查结果，使我们能够再次确认太阳活动的长期周期为 ∼200 年。

引用次数: 0