Port congestion and shipping delays are increasingly the product of geopolitical risk layered on top of extreme weather, rather than either shock acting alone, according to analysis published by insurance broker Marsh.

The report, titled "Port congestion and shipping delays: The impact of geopolitical risks and extreme weather on the marine market," frames a market in which two categories of disruption that freight planners once treated as separate are now arriving together — and doing compounding damage to schedules, asset availability and insurance exposure.

Marsh does not lead with a rate number. That absence is itself worth noting. What the analysis offers instead is a structural argument: the marine market's exposure profile has shifted, and shippers, carriers and forwarders should reprice their assumptions accordingly.

What is driving the congestion?

The report identifies two converging pressure points:

• Geopolitical risk — conflict-driven re-routings, chokepoint instability and sanctions-related friction that force tonnage onto longer, less efficient paths.
• Extreme weather — events that close terminals, slow port operations and stack up vessel arrivals faster than yards can clear them.

The compounding effect matters more than either input alone. A re-routed service absorbing extra transit days has no schedule buffer left when a storm shuts a berth for 72 hours. Congestion in that scenario is not an operational nuisance; it is a structural outcome.

For carriers, the commercial consequence is capacity absorption — vessels tied up in queues are vessels not earning on the next rotation. For shippers, it is reliability: quoted transit times become optimistic, and buffer stock or premium freight becomes a recurring cost rather than an exception. For forwarders, it is a margin squeeze between carrier schedule slippage and customer commitments.

What does this mean for marine insurance buyers?

Marsh, as one of the world's largest insurance brokers, writes from the exposure-management side of the ledger. The marine market has spent several years repricing risk after a run of high-loss years, and the report's core warning is that congestion itself changes the risk profile of cargo and hull cover.

Vessels waiting at anchor face elevated exposure — collision, grounding and weather damage while stationary. Cargo sitting in congested ports faces extended dwell time, which raises theft, damage and delay-related claim potential. Neither risk is new. What is new, in Marsh's framing, is the frequency with which both now occur simultaneously.

The report's implicit message to cargo owners: review policy wordings on delay, spoilage and storage extensions before the next disruption, not during it.

What Marsh does not say

A skeptical reading of the analysis is warranted. The report's title promises an assessment of "impact," but as presented it is a risk-framing document rather than a quantified loss study. There is no tonnage figure, no TEU count of delayed boxes, no dollar estimate of congestion-driven claims in the material as circulated.

That is a familiar pattern in broker-published thought leadership: the direction of risk is clearly flagged, the magnitude is left to the reader's actuary. Buyers should treat it as a prompt for internal exposure modelling, not as a dataset.

The forward view

The trajectory Marsh points to is one of persistent, overlapping disruption — geopolitical tension showing no sign of easing and weather volatility trending upward — which suggests port congestion will remain a recurring feature of ocean freight planning rather than an episodic one, and that schedule buffers, longer contractual transit allowances and tighter insurance reviews will stay on shippers' agendas through 2025.