Abstract To improve our understanding of the role electromagnetic ion cyclotron (EMIC) waves in radiation belt electron dynamics, we perform a comprehensive analysis EMIC wave‐induced resonant scattering outer zone relativistic (>0.5 MeV) electrons and resultant loss time scales with respect to wave band, L shell, normal angle model. The results demonstrate that while H + ‐band dominate losses ~1–4 MeV electrons, it is He O prevail over pitch diffusion ultrarelativistic at higher...

Abstract This is a companion study to Liang et al. (2014) which reported “reversed” energy‐latitude dispersion pattern of ion precipitation in that the lower energy extends latitudes than higher‐energy precipitation. Electromagnetic cyclotron (EMIC) waves central plasma sheet (CPS) have been suggested account for this reversed‐type To further investigate association, we perform comprehensive pitch angle diffusion rates induced by EMIC wave and resultant proton loss timescales at L = 8–12...

Abstract A statistical analysis of sporadic E layer recorded from September 2011 to 2015 at four Chinese ionospheric sounding stations Mohe (122.37°E, 53.50°N), Beijing (116.25°E, 40.25°N), Wuhan (114.61°E, 30.53°N), and Hainan (109.13°E, 19.52°N) is presented investigate the characteristics middle latitudes over China. The occurrence in midlatitude China region shows strong dependence on local time season, consistent with previous studies. prominent daytime summer season. results also...

We report a statistical study of medium-scale traveling ionospheric disturbances (MSTIDs) during 2014–2017 in the low-latitude China region using Hong Kong Continuously Operating Reference Stations network with baseline length 10–15 km. Polynomial fitting and multichannel maximum entropy method are utilized to derive MSTID parameters from global positioning system total electron content data. find that MSTIDs can be sorted into three types this region. One type is daytime MSTIDs, which...

Knowledge of the radio channel in urban environments is key importance many critical applications, such as wireless communication and autonomous driving. This study proposes a promising wave propagation model for complex scenarios. First, electrical parameters different object classes are estimated by utilizing deep-learning-based semantic segmentation applied to point cloud. Second, highly accurate 3-D geometrical electromagnetic (EM) environment obtained surface reconstruction. Finally,...

Effective monitoring and management of potato late blight (PLB) is essential for sustainable agriculture. This study describes a methodology to improve PLB identification on large scale. The method combines unsupervised supervised machine learning algorithms. To the accuracy regression model, used K-Means algorithm in conjunction with morphological operations identify growth areas. Input data consisted monthly NDVI from Sentinel-2 VH bands Sentinel-1 (covering year 2021). results were...

Abstract Recent advances in computing technologies have renewed interest the intelligent systems for automatic interpretation of ionograms, images obtained by remote sensing ionospheric plasma. The ionogram “autoscaling” techniques based on template matching method, previously rendered unrealistic their complexity, now become feasible. This work presents an scaling technique extracting main features F 1 and 2 layers ionosphere, such as critical frequency virtual height, from vertical...

Abstract Spread F on ionograms has been considered to be a phenomenon mainly occurred at nighttime. This study presented case of daytime spread observed by the ionosonde installed Puer (PUR; 22.7°N, 101.05°E; dip latitude 12.9°N), where that lasted for more than 2 h (about 08:30 LT~10:45 LT) was 14 November 2015. To investigate possible mechanism, recorded PUR and Chiang Mai (18.76°N, 98.93°E; 9.04°N) were used in this study. We found traveling ionospheric disturbances before occurrence ....

Abstract Coupling of ionospheric E and F regions in the midlatitude region has been studied for a couple years. In this study, we investigate nighttime disturbances China by using Wuhan ionosonde, very high frequency coherent scatter radar, Mengcheng airglow imager. We present two case studies simultaneous observations diffuse sporadic ( s) layers, quasiperiodic echoes irregularities, spread , medium‐scale traveling disturbances. Results indicate that s layers irregularities can be...

This study presents observations of nighttime spread F/ionospheric irregularities and Es at low middle latitudes in the South East Asia longitude China sectors during recovery phase 7–9 September 2017 geomagnetic storm. In this study, multiple observations, including a chain three ionosondes located about 100°E, Swarm satellites, Global Navigation Satellite System (GNSS) ROTI maps, were used to development process evolution characteristics latitudes. Interestingly, F intense simultaneously...

A new high-frequency backscatter radar (Wuhan Ionospheric Oblique Backscattering Sounding System) for ionospheric sensing and study has been developed. With the system design, oblique sounding can be achieved in this just through simply loading appropriate software. Furthermore, due to alternate transmission reception equal interval, detect state range of a few thousand kilometers achieve largest gain applied pseudorandom sequences. In addition, usually obtains 27-dB from phase coded pulse...

Abstract Motivated by the observations and linear theory analysis of ionospheric irregularities at Mars, we performed numerical simulations nonlinear evolution electromagnetic gradient drift instability in Martian dynamo region. The seeding source is perturbation zonal neutral wind. We found that electric fields induced can convect lower density plasma into higher altitudes. Then, associated magnetic field cause velocity shear plasma, which Kelvin–Helmholtz altitude. instabilities...

Wuhan Ionospheric Oblique Backscattering Sounding System (WIOBSS) is a high‐frequency (HF) sky wave over‐the‐horizon radar developed for ionospheric research and HF channel management. This radar, located in (30.35°N, 114.33°E) has been under construction by the Ionosphere Lab of University since 2002. WIOBSS uses long coded pulses pulse compression to achieve good sensitivity measures bitemporal response, scattering function, phase echoes simultaneously then displays processed data as...

Abstract. The total solar eclipse of 22 July 2009, was visible from some regions China and the intense sporadic-E (Es) that broke out during period over eastern provided a unique chance to study effects on Es-layer. ground based high-frequency (HF) vertical-incidence oblique-incidence backscatter radio systems in Wuhan an HF oblique receivers located Suzhou were operated detect vertical, ionograms 23 recorded, processed analyzed. analyzing results show critical frequency Es, hop number power...

Abstract The driving mechanism of the midlatitude field‐aligned irregularities (FAIs) has been in dispute for many years. experimental observations were carried out during solar eclipse 22 July 2009 Wuhan, China, to study possibility wave‐driven irregularities. A high‐frequency coherent scatter radar was used detect E region An ionosonde applied record trace gravity waves ionosphere. FAIs occurred at end with fluctuant Doppler. At same time, oscillations on fE s (maximum reflecting frequency...