What if a grounded ship shuts the Bosphorus to exports?
A grounding that shuts the Bosphorus traps Black Sea wheat and Russian Urals crude, lifting CBOT/Matif wheat and a Brent premium as ~3M bbl/day and major grain flows back up. Rhymes with the 2022-23 Black Sea grain-corridor disruptions that whipsawed wheat. Russia/Ukraine/Kazakhstan are the trapped exporters; Turkey is the gatekeeper. The forward angle is the climate_supply root is the wrong driver - this is a chokepoint/geopolitical-logistics event, so wheat belongs in the cascade more than it currently appears.
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The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (electric blue) over time vs the market's (Polymarket, amber), from the past toward the 0–6 months horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. Loading the probability audit trail…
What it would mean
If this plays out, it is a risk-off shock. A grounded grain vessel shuts the Bosphorus, trapping Black Sea wheat and Russian crude exports for weeks. The trigger decomposes into signed root‑shocks — Geopolitical risk ▲ · Oil supply risk ▲ · Food inflation ▲ · Inflation surprise ▲ — which propagate through our causal graph to the markets below.