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The known effects of thermodynamics and aerosols can well explain the thunderstorm activity over land, but fail over oceans. Here, tracking the full lifecycle of tropical deep convective cloud clusters shows that adding fine aerosols significantly increases the lightning density for a given rainfall amount over both ocean and land. In contrast, adding coarse sea salt (dry radius > 1 μm), known as sea spray, weakens the cloud vigor and lightning by producing fewer but larger cloud drops, which accelerate warm rain at the expense of mixed-phase precipitation. Adding coarse sea spray can reduce the lightning by 90% regardless of fine aerosol loading. These findings reconcile long outstanding questions about the differences between continental and marine thunderstorms, and help to understand lightning and underlying aerosol-cloud-precipitation interaction mechanisms and their climatic effects.

The Communication/Navigation Outage Forecast System (C/NOFS) satellite's VEFI payload performed frequent recordings of the vector electric field in the band 0–16 kHz during the epoch 2008–2014. The Vector Electric Field Instrument (VEFI) was supported by ion‐composition data from the Coupled Ion Neutral Dynamics Investigation (CINDI) instrument. We focus here on statistics of these “burst‐mode” recordings, of which 6,890 (mostly ~12‐s duration) records meet stringent quality‐control criteria, allowing inference of the wave vectorkand its orientation relative to the Earth's magnetic fieldB₀. The 6,890 records occur between ±13° (geographic) latitude and between ~ 400‐ and 850‐km altitude, mostly in the topside ionosphere. The wave activity is dominated by terrestrial lightning. We analyze the whistler‐wave intensity and polarization for each pixel in the time‐frequency spectrogram for each record. We then gather weighted statistics on wave polarization, naturally weighted by wave intensity. In this manner we arrive at statistical results that represent the bulk of the energy flow due to whistler waves. Despite rather nonstationary statistics, we can reach three empirical results.

We see no evidence of a low‐latitude suppression of whistler‐wave activity, in contrast to the predictions of models of transmission through a laminar ionosphere.