Ionospheric Irregularities and Acoustic/Gravity Wave Activity Above Low‐Latitude Thunderstorms

• Published in: Geophysical research letters 2018-01, Vol.45 (1), p.90-97
• Main Author: Lay, Erin H.
• Format: Article
• Language: English
• Subjects: Acoustic gravity waves; Area; Bubbles; Diurnal variations; Equator; Equatorial regions; Fluctuations; Gravitational waves; Gravity; Gravity waves; Ionosphere; Ionospheric electron content; Ionospheric irregularities; Irregularities; Latitude; Lightning; Lightning location; Plasma bubbles; scintillation; Solar activity; Solar radiation; Space weather; Summer; Thunderstorm activity; Thunderstorms; Total Electron Content; Winter
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2017GL076058

Ionospheric irregularities due to plasma bubbles, scintillation, and acoustic/gravity waves are studied in the low‐latitude ionosphere in relation to thunderstorm activity. Ionospheric total electron content (TEC) measurements from the Low Latitude Ionospheric Sensor Network and lightning measurements from the World‐Wide Lightning Location Network are compared during two summer months and two winter months in 2013. Large amplitude fluctuations in TEC are found to have a strongly peaked diurnal pattern in the late evening and nighttime summer ionosphere. The maximum magnitude and coverage area of these fluctuations increases as thunderstorm area increases. Summertime midamplitude fluctuations do not exhibit the same diurnal variation but do increase in magnitude and coverage area as thunderstorm area increases. Wintertime ionospheric fluctuations do not appear to be related to thunderstorm activity. These findings show that thunderstorms have an observable effect on magnitude and coverage area of ionospheric fluctuations. Plain Language Summary The ionosphere is a part of the atmosphere that is ionized (made into a plasma) by incoming solar radiation. Waves and bubbles can be created in this plasma. It is thought that in regions of the ionosphere near the equator, the primary cause of these bubbles and waves is from above (solar activity and space weather). However, in regions farther from the equator, it is known that thunderstorms near the ground can cause the bubbles and waves. In this paper, we look at the ionosphere near the equator during times with thunderstorms and times without thunderstorms. We measure the area covered by bubbles and waves and the size of these bubbles and waves. We find that there are more bubbles and waves, and they are bigger in magnitude when there is more thunderstorm activity. Therefore, we conclude that thunderstorms have an observable effect on the ionosphere near the equator. Key Points Thunderstorm activity has an observable effect on the magnitude and coverage area of low‐latitude ionospheric irregularities Summertime large amplitude ionospheric irregularities exhibit diurnal variability, peaking in the early evening hours Summertime ionospheric fluctuations are enhanced in magnitude and coverage area in association with increased thunderstorm activity