Global Distribution of Key Features of Streamer Corona Discharges in Thunderclouds.

We present nighttime worldwide distributions of key features of Blue LUminous Events (BLUEs) detected by the Modular Multispectral Imaging Array of the Atmosphere-Space Interaction Monitor. Around 10% of all detected BLUEs exhibit an impulsive single pulse shape. The rest of BLUEs are unclear (impulsive or not) single, multiple or with ambiguous pulse shapes.

Multi-Pulse Corona Discharges in Thunderclouds Observed in Optical and Radio Bands.

How lightning initiates inside thunderclouds remains a major puzzle of atmospheric electricity. By monitoring optical emissions from thunderstorms, the Atmosphere-Space Interactions Monitor (ASIM) onboard the International Space Station is providing new clues about lightning initiation by detecting Blue LUminous Events (BLUEs), which are manifestations of electrical corona discharges that sometimes precedes lightning. Here we combine optical and radio observations from a thunderstorm near Malaysia to uncover a new type of event containing multiple optical and radio pulses.

Analysis of Blue Corona Discharges at the Top of Tropical Thunderstorm Clouds in Different Phases of Convection.

We report on observations of corona discharges at the uppermost region of clouds characterized by emissions in a blue band of nitrogen molecules at 337 nm, with little activity in the red band of lightning leaders at 777.4 nm. Past work suggests that they are generated in cloud tops reaching the tropopause and above.

Spectral Observations of Optical Emissions Associated With Terrestrial Gamma-Ray Flashes.

The Atmosphere-Space Interactions Monitor measures Terrestrial Gamma-Ray Flashes (TGFs) simultaneously with optical emissions from associated lightning activity. We analyzed optical measurements at 180-230, 337, and 777.4 nm related to 69 TGFs observed between June 2018 and October 2019.