Is a clear-air or mean-rain-rate radar twin right when rain comes in cells?

research/rain-twin

Clear-air or mean-rain-rate radar twin vs intermittent storm-cell attenuation: Jensen gap 1.52× in the rain-rate power law, Lambert-W mean-rate range reached by only 39% of real fields, mean-matching barely helps, a rain ensemble scores Brier 0.038 vs 0.101 clear air. Stylised.

9 tests

What it found

Radar detection range under intermittent rain attenuation. The power law in rain rate has a Jensen gap (1.52× the mean-rate attenuation), so a mean-rate twin (closed-form Lambert W range, 18.84 km) is reached by only 39% of real storm fields; matching the mean attenuation barely helps (Brier 0.054 vs 0.055). A rain ensemble scores 0.038 vs 0.101 for clear air, and long cells flip the mean-rate twin from optimistic to pessimistic. Stylised: simulated rain, illustrative coefficients, no radar data.

A figure from its own output

Figure produced by research/rain-twin: brier_vs_cell — rain-twin/experiments/brier_vs_cell.svg, written by the project's own experiment code.

Paper, code and results

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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.