Select two or more hazards to assess together — independent of
what's shown on the map. Method & references →
1. Select hazards
Select at least 2 hazards to continue.
2. Assessment type
Weights
Each selected hazard's risk contributes
to one composite by weight — default equal, adjust if one hazard should
dominate for this area.
Total: 100%
(must equal 100% to run)
Multi-hazard composite risk — Analamanga
40% Low · 25% Moderate · 35% High, at the weights
above — every selected hazard's risk combined into one district-wide
composite, not separate ratings to mentally merge.
Cyclone → Flood
| Primary risk | High |
| Secondary risk (independent) | Elevated |
| Combined / compound risk | High |
Escalated from Elevated
to High: triggering probability ≥50% and time lag ≤24h both hold (short-window
cascade, De Ruiter et al. 2020), so the secondary hazard's independent risk is not
treated as a separate event.
Worked example (same chain recorded on Impact → Historical Events): Cyclone
Severe → cascading rainfall → Flood
threshold breach Warning → localized
landslide risk elevated — a 3-hazard chain, built by running this workspace
twice (Cyclone→Flood, then Flood→Landslide).
Full hazard-chain catalog →