TSV-003 · Rainfall Provenance Drift

HYPOTHESIS

Has the synoptic pathway associated with major Townsville rainfall events changed?

HYPOTHESIS / RESEARCH · confidence Insufficient evidence

Townsville major-rainfall provenance may have shifted among northern-tropical, Coral Sea, eastern maritime, western/inland and mixed pathways. This is a hypothesis, not a finding.

What exists now

141

days ≥ 100 mm at Townsville Aero

87

non-overlapping 3-day totals ≥ 200 mm

Threshold catalogue only. Classification pipeline is not implemented in v0.1.

Candidate classes — unused

  • · northern tropical
  • · north-eastern / Coral Sea
  • · eastern maritime
  • · western / inland
  • · north-western
  • · mixed

Pathway and moisture source are different questions. Neither is classified in v0.1.

Evidence

  • · 141 calendar days with ≥100 mm at Townsville Aero are catalogued from the GHCN daily series.
  • · 87 non-overlapping 3-day totals ≥200 mm are catalogued.
  • · No reproducible synoptic or moisture-source classification has been validated, so no decade-to-decade provenance trend is reported as fact.

Counter-evidence

  • · Event counts can rise or fall with observing practice, cyclone classification and a single landfalling system.
  • · Pathway and moisture source are different questions and must not be collapsed.

What would falsify the hypothesis

  • · No statistically meaningful change in classified event pathways across eras.
  • · Apparent shift disappears under reasonable event thresholds.
  • · Shift explained by observational or reanalysis artefacts.
  • · Moisture-source analysis contradicts the pathway interpretation.
  • · Result is not robust across classification methods.

Recent ≥100 mm days — catalogue only

DateRainfall
2025-02-01284 mm
2025-02-02260.6 mm
2025-02-03165.2 mm
2025-02-07101.2 mm
2025-03-19301.4 mm
2025-03-20110.6 mm
2025-03-24119.8 mm
2025-03-26115 mm
2025-12-30142.2 mm
2026-01-01223 mm
2026-01-05129.8 mm
2026-01-27119.8 mm