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Electric current in the ground after a nearby lightning discharge. A person can bridge points of different electric potential, creating indirect exposure without the main channel striking the body.

At fixed precursor emissions, more tropospheric water vapor in a warmer climate promotes the ozone-photolysis/O(${}^{1}D$)-water loss route, especially in clean tropical lower air. Warmer conditions also accelerate some precursor chemistry; lightning nitrogen oxides, stagnation and stronger stratosphere-to-troposphere ozone transport can increase ozone elsewhere. Thus near-surface regional ozone and the integrated tropospheric burden can respond differently. There is no universal decrease of the global burden from the humidity effect alone; competing chemistry and transport must be evaluated consistently.

For the chemical sink, ${\tau }_{\mathrm{C}{\mathrm{H}}_4}\sim 1/(k[\mathrm{OH}])$. Warming increases the methane–hydroxyl radical rate constant and, with increased water vapor, often increases hydroxyl radical production, tending to shorten the chemical lifetime. Changes in ozone photodissociation, radical recycling, lightning and competing carbon monoxide/VOC/methane consumption can reinforce or oppose that trend. Increasing methane itself consumes hydroxyl radicals and lengthens its methane perturbation lifetime. The physical/chemical warming tendency should therefore be separated from scenarios with changed emissions; shorter chemical lifetime at fixed precursor conditions is a tendency, not an unconditional prediction for the future atmosphere.^[ref]

A direct lightning strike is unnecessary. A nearby strike can produce a ground current, putting the feet at different electric potentials and driving current through the body by a step voltage. A side flash from a struck object or conduction along a contacted conductor also provides an indirect current path.^[ref]

Rapid air heating by a nearby lightning discharge also produces an expanding pressure disturbance. Its blast can impart a mechanical impulse, causing a fall or blunt injury without current passing through the person.^[ref]

The absence of a direct strike therefore does not distinguish electrical incapacity from mechanical displacement. Observations would be needed to identify the mechanism in a particular event.