Global Trade Shock Simulator

Inspiration

I chose the 2021 Suez Canal blockage to study how a physical interruption can affect shipping after the canal reopens. It also raised a question: what can the available evidence actually tell us about the wider economic effects?

What I built

The Global Trade Shock Simulator (GTSS) is a theoretical framework and retrospective case study, not a coded simulator. It traces a disruption through six stages: the shock, exposure and concentration, substitutability, interconnectedness, transmission, and outcomes.

I queried IMF PortWatch for daily Suez transit calls from 15–31 March 2021. The recorded calls fell to 2 on 25 March, compared with 47–61 per day from 15–21 March. I compared that series with official and carrier reports, satellite-AIS research, and published economic models. The Suez Canal Authority and Reuters reported a queue of 422 ships when the Ever Given was refloated; Maersk reported rerouting 15 vessels with partners.

What I learned

Transit-call counts show vessel activity, not cargo losses or GDP effects. The queue, carrier reports, and economic models describe different populations and outcomes, so their figures cannot be treated as interchangeable. The paper maps that evidence and its limits; it does not claim a new causal estimate of the blockage’s total cost.

Challenges

The main challenge was keeping sources with different definitions and scopes separate. I had to distinguish observed traffic from reported operational effects and modeled estimates, and avoid presenting model outputs as realized losses.