Understanding the day‐to‐day variability of equatorial plasma bubble (EPB) irregularities has been a major challenge for many decades that makes the deterministic prediction of EPBs remain elusive. In the present study, we report a case of intense and periodic EPBs observed during 8 and 9 April 2013 by the 47‐MHz Equatorial Atmosphere Radar at Kototabang, Indonesia. The periodic EPBs separated by about 200–250 km were initiated before sunset. The presunset onset and development of these periodic EPBs were discussed in light of the gravity waves (GWs) excited in connection with the deep convection due to the tropical cyclone (TC) Victoria. The outgoing long‐wave radiation measurement by very high‐resolution radiometer (VHRR) onboard Indian meteorological satellite Kalpana‐1 shows the occurrence of deep convective activity during these days. The presence of upward propagating GWs from the deep convective region associated with TC Victoria was confirmed using the GPS radio occultation (GPS‐RO) observations in the troposphere and stratosphere. The GW signatures at ionospheric altitudes were also observed from the Ionosonde observations over magnetic equator, and medium‐scale (~300 km) GWs were observed from the GPS‐TEC (Total Electron Content) data near to the magnetic equator and cyclone center. From the GW parameters observed from GPS‐TEC and GPS‐RO, we surmise that the secondary GWs generated by the dissipation of primary GWs associated with TC Victoria could have served as a seeding source on the generation of periodic EPBs during these two consecutive days.

中文翻译：

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重力波与热带气旋相关的周期性赤道等离子气泡的播种：案例研究

几十年来，了解赤道血浆气泡（EPB）不规则性的日常变化一直是一项重大挑战，这使得对EPB的确定性预测仍然遥不可及。在本研究中，我们报告了印度尼西亚科托邦47-MHz赤道大气雷达在2013年4月8日至9日观测到的强烈周期性EPB的情况。间隔约200-250 km的周期性EPB在日落之前启动。鉴于与热带气旋维多利亚（TC）引起的深对流有关的重力波（GW）激发，讨论了这些周期性EPB的日落前发作和发展。印度气象卫星Kalpana-1上的超高分辨率辐射计（VHRR）进行的出射长波辐射测量表明，在这几天发生了深对流活动。利用对流层和平流层中的GPS无线电掩星（GPS-RO）观测结果，证实了与维多利亚维多利亚相关的深对流区域中向上传播的GWs的存在。电离层高度的GW特征也从磁赤道上的离子探空仪观测中观察到，并且从磁赤道和旋风中心附近的GPS-TEC（总电子含量）数据中观察到了中尺度（〜300 km）GWs。从GPS‐TEC和GPS‐RO观测到的GW参数中，我们推测由与TC Victoria相关的主要GW的消散而产生的次要GW可能已连续两天成为定期EPB生成的种子源。