scholarly journals The Simultaneous Observations of Nighttime Ionospheric E Region Irregularities and F Region Medium-Scale Traveling Ionospheric Disturbances in Midlatitude China

2018 ◽  
Vol 123 (6) ◽  
pp. 5195-5209 ◽  
Author(s):  
Chen Zhou ◽  
Qiong Tang ◽  
Fuqing Huang ◽  
Yi Liu ◽  
Xudong Gu ◽  
...  
Keyword(s):  
Ionospheric Disturbances ◽  
Medium Scale ◽  
Traveling Ionospheric Disturbances ◽  
F Region ◽  
E Region

scholarly journals Observational evidence of coupling between quasi-periodic echoes and medium scale traveling ionospheric disturbances

2007 ◽  
Vol 25 (10) ◽  
pp. 2185-2194 ◽  
Author(s):  
S. Saito ◽  
M. Yamamoto ◽  
H. Hashiguchi ◽  
A. Maegawa ◽  
A. Saito
Keyword(s):  
Observational Evidence ◽  
Ionospheric Disturbances ◽  
Gps Receiver ◽  
Interferometric Imaging ◽  
Geomagnetic Field Line ◽  
Medium Scale ◽  
Traveling Ionospheric Disturbances ◽  
F Region ◽  
Mu Radar ◽  
E Region

Abstract. We have found that quasi-periodic (QP) echoes in the E region were well defined when medium scale traveling ionospheric disturbances (MSTIDs) in the F region were present. The appearance and disappearance of the MSTIDs observed with the dense GPS receiver network are well correlated with the development and decay of QP echoes observed with the Middle-and-Upper atmosphere (MU) radar. Interferometric imaging of the QP echoes obtained using the MU radar shows that bands of echoing regions aligned northwest to southeast drift southwestward, and their wavefront and propagation direction are the same as those of MSTIDs. This result confirms the expectation of Hysell et al. (2002) who observed band structures in QP echoes by using the MU radar and suggested their relation to MSTIDs. We found observational evidence that the midlatitude E- and F regions are coupled through the geomagnetic field line, although we could not clearly ascertain which of the two regions is the source.

scholarly journals Probing of medium-scale traveling ionospheric disturbances using HF-induced scatter targets

2006 ◽  
Vol 24 (9) ◽  
pp. 2333-2345 ◽  
Author(s):  
N. F. Blagoveshchenskaya ◽  
T. D. Borisova ◽  
V. A. Kornienko ◽  
I. V. Moskvin ◽  
M. T. Rietveld ◽  
...  
Keyword(s):  
Pump Wave ◽  
Computational Technique ◽  
Ionospheric Disturbances ◽  
Ionospheric Layer ◽  
Medium Scale ◽  
Traveling Ionospheric Disturbances ◽  
North East ◽  
The North ◽  
E Region ◽  
The Waves

Abstract. Experimental results from the Tromsø and Sura heating experiments at high and mid-latitudes are examined. It is shown that the combination of HF-induced target and bi-static HF Doppler radio scatter observations is a profitable method for probing medium-scale traveling ionospheric disturbances (TIDs) at high and mid-latitudes. HF ionospheric modification experiments provide a way of producing the HF-induced scatter target in a controlled manner at altitudes where the sensitivity to TIDs is highest. Bi-static HF Doppler radio scatter observations were carried out on the London-Tromsø-St. Petersburg path in the course of a Tromsø heating experiment on 16 November 2004 when the pump wave was reflected from an auroral Es-layer. During Sura heating experiments on 19 and 20 August 2004, when the HF pump wave was reflected from the F2 ionospheric layer, multi-position bi-static HF Doppler radio scatter observations were simultaneously performed at three reception points including St. Petersburg, Kharkov, and Rostov-on-Don. Ray tracing and Doppler shift simulations were made for all experiments. A computational technique has been developed allowing the reconstruction of the TID phase velocities from multi-position bi-static HF Doppler scatters. Parameters of medium-scale TIDs were found. In all experiments they were observed in the evening and pre-midnight hours. TIDs in the auroral E-region with periods of about 23 min were traveling southward at speeds of 210 m/s. TIDs in the mid-latitudinal F-region with periods from 20 to 45 min travelled at speeds between 40 and 150 m/s. During quiet magnetic conditions the waves were traveling in the north-east direction. In disturbed conditions the waves were moving in the south-west direction with higher speeds as compared with quiet conditions. Possible sources for the atmospheric gravity waves at middle and high latitudes are discussed.

scholarly journals Statistical study of medium-scale traveling ionospheric disturbances in low-latitude ionosphere using an automatic algorithm

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Pin-Hsuan Cheng ◽  
Charles Lin ◽  
Yuichi Otsuka ◽  
Hanli Liu ◽  
Panthalingal Krishanunni Rajesh ◽  
...  
Keyword(s):  
Climate Model ◽  
Geomagnetic Latitude ◽  
Detection Algorithm ◽  
Support Vector ◽  
Electron Content ◽  
Ionospheric Disturbances ◽  
Low Latitude ◽  
Total Electron ◽  
Medium Scale ◽  
Traveling Ionospheric Disturbances

AbstractThis study investigates the medium-scale traveling ionospheric disturbances (MSTIDs) statistically at the low-latitude equatorial ionization anomaly (EIA) region in the northern hemisphere. We apply the automatic detection algorithm including the three-dimensional fast Fourier transform (3-D FFT) and support vector machine (SVM) on total electron content (TEC) observations, derived from a network of ground-based global navigation satellite system (GNSS) receivers in Taiwan (14.5° N geomagnetic latitude; 32.5° inclination), to identify MSTID from other waves or irregularity features. The obtained results are analyzed statistically to examine the behavior of low-latitude MSTIDs. Statistical results indicate the following characteristics. First, the southward (equatorward) MSTIDs are observed almost every day during 0800–2100 LT in Spring and Winter. At midnight, southward MSTIDs are more discernible in Summer and majority of them are propagating from Japan to Taiwan. Second, northward (poleward) MSTIDs are more frequently detected during 1200–2100 LT in Spring and Summer with the secondary peak of occurrence between day of year (DOY) 100–140 during 0000–0300 LT. The characteristics of the MSTIDs are interpreted with additional observations from radio occultation (RO) soundings of FORMOSAT-3/COSMIC as well as modeled atmospheric waves from the high-resolution Whole Atmosphere Community Climate Model (WACCM) suggesting that the nighttime MSTIDs in Summer is likely connected to the atmospheric gravity waves (AGWs).

Sign in / Sign up

Export Citation Format

Share Document