A statistical analysis of medium-scale traveling ionospheric disturbances during 2014\u20132017 using the Hong Kong CORS network

Guanyi Chen,Xiang Wang,Chen Zhou,Zhengyu Zhao,Jiaqi Zhao,Yi Liu,Qiong Tang

doi:10.1186/s40623-019-1031-9

Abstract

We report a statistical study of medium-scale traveling ionospheric disturbances (MSTIDs) during 2014–2017 in the low-latitude China region using the Hong Kong Continuously Operating Reference Stations network with a baseline length of 10–15 km. Polynomial fitting and the multichannel maximum entropy method are utilized to derive MSTID parameters from global positioning system total electron content data. We find that MSTIDs can be sorted into three types in this region. One type is daytime MSTIDs, which are mainly distributed during 1000–1700 local time (LT) in spring, autumn and winter. The second type is nighttime MSTIDs, which mainly occur from 2200 to 0300 LT in spring and summer. The third type is morning MSTIDs, mainly occurring from 0500 to 0700 LT in spring and autumn. No clear difference in the MSTID parameters is distinguishable between the cyclone period and non-cyclone period, which may be due to the distance restriction for cyclone identification and different propagation distances of the primary gravity waves (GWs) and secondary GWs.

Highlights

Medium-scale traveling ionospheric disturbances (MSTIDs) are typical wavelike perturbations of ionospheric plasma with wavelengths of hundreds of kms, phase velocities of hundreds of m/s and periods of between 10 min and 1 h (Hunsucker 1982)
We analyzed total electron content (TEC) data obtained by continuous observations from the Hong Kong Continuously Operating Reference Stations (CORS) network from 2014 to 2017
To investigate the seasonal variation in the MSTID characteristics, the one-year interval is divided into four seasons: spring (February–April), summer (May–July), autumn (August–October), and winter a The statistical distribution of s2 b The statistical distribution of s3

Summary

Introduction

Medium-scale traveling ionospheric disturbances (MSTIDs) are typical wavelike perturbations of ionospheric plasma with wavelengths of hundreds of kms, phase velocities of hundreds of m/s and periods of between 10 min and 1 h (Hunsucker 1982). TIDs have been intuitively thought to be plasma manifestations of atmospheric gravity waves (AGWs) propagating in the thermosphere (Hines 1960; Hooke 1968; Hunsucker 1982; Kirchengast et al 1996). Based on the research of Hines, Klostermeyer (1972) supplied a full-wave solution of gravity wave propagation in a thermospheric model and compared it with the data observed from ionograms. Xiao et al (2007) suggested that during the existence of a typhoon, which is one of the important ground sources of wavelike disturbances in the troposphere, there are almost always MSTIDs in the ionosphere. Xu et al (2015) once used six all-sky imagers and satellite sensors from Fengyun-2 (FY-2) and reported obvious concentric gravity wave events in the China region, which is associated with strong

Results

Discussion

Conclusion