Assessment of Unusual Gigantic Jets observed during the Monsoon season: First observations from Indian Subcontinent

Area of Science:

• Atmospheric science
• Electromagnetism
• Geophysics

Background:

• Gigantic Jets are rare electrical phenomena connecting thunderstorm cloud tops to the ionosphere (~90 km altitude).
• Sporadic observations have been reported globally since 2002, but not previously from the Indian subcontinent.

Purpose of the Study:

• To report the first observations of Gigantic Jets in the Indian subcontinent.
• To document novel characteristics of these electrical discharges during the monsoon season.

Main Methods:

• Ground-based observations of electrical discharges over the Indo-Gangetic plains.
• Analysis of electromagnetic signatures and high-speed propagation characteristics.
• Cloud-top altitude and charge distribution analysis.

Main Results:

• Two storms produced four Gigantic Jets with unprecedented characteristics.
• Jets propagated ~37 km upwards in ~5 ms at ~7.4 × 10^6 ms^-1, disappearing within 40-80 ms.
• Negative polarity jets transported ~17-23 C of charge; one exhibited unusual horizontal displacement (~10 km).

Conclusions:

• Gigantic Jets exhibit diverse characteristics, including rapid propagation and horizontal displacement.
• Observations suggest Gigantic Jets may bend when initiated at cloud edges with charge imbalances.
• These findings expand the understanding of high-altitude electrical discharges in the Earth's atmosphere.