| Jing YANG1,2, Ningyu LIU3, Mitsuteru SATO4, Gaopeng LU1,2, Yu Wang5, Guili FENG6
1Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029;
2 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing, 210044;
3Space Science Center, Department of Physics, University of New Hampshire, Durham, NH 03824, USA;
4 Hokkaido University, Department of Cosmosciences, Sapporo 060-0810, Japan;
5State Grid Electric Power Research Institute, Wuhan 430074, China;
6Shandong Research Institute of Meteorology, Jinan 250031, China
Corresponding author: Jing Yang (yangj@mail.iap.ac.cn)
Abstract: This paper reports observation of two negative sprites and three positive sprites over a mesoscale convective system in a 15 min window. The negative sprites occurred during strong convection, indicated by the increase of the area of the thundercloud with radar echo top of 8-11, 9-11 and 6-12 km. The strong convection and large wind shear in thunderstorm middle and upper region provide favorable conditions to produce the parent cloud-to-ground (CG) lightning discharges of negative sprites. The parent CGs for the two negative sprites are likely to be hybrid intracloud-negative cloud-to-ground lightning (IC-NCG). The peak current of the parent CG of one of the negative sprites is -106.6 kA, agreeing with the values reported previously; the parent flash of the other negative sprite may be a negative CG with two return strokes with peak currents of -39.7 kA and -40.9kA, suggesting that negative sprites can also be produced by –CGs with moderate peak currents. Finally, the two negative sprites were separated by 2.66 min in time but have similar spatial features, indicating that the effects of sprites on the mesosphere may last on the order of minutes.
Keywords: negative sprite; positive sprite; radar; lightning; magnetic field. |