>What about enacting a law that says "if you use cheating devices at all, you can't dock in our ports"?

When 99.9% of vessels are doing the cheating, the shipping companies would say you would really like your people to go on a diet don’t you?

You are making it harder than it is. You can't pump any oil overboard anywhere, well above about 1 ppm if I remember correctly. In the industry you hear all the time about magic pipes being found during port state control and other inspections leading to extremely high fines and prison time. For reference, a magic pipe bypasses the oil separator making you able to discharge anything.

Simply add another annex to MARPOL regarding discharge of sulfur and the industry will follow, penalties for breaking MARPOL are usually personal and not on the shipping company. Though, as always with the maritime industry the international manner makes any change slow.

https://en.wikipedia.org/wiki/MARPOL_73/78

MARPOL is utterly toothless and not enforced, and also only really covers 12 nautical miles from land.

12 nm is enough, as most inspections occur close to shore.

Cool.. let's enforce it.

That's not going to happen. For example London is basically setting cycling safety regs for lorries [1], or in the US, California is basically setting the emissions limits for vehicles.

All it takes is for the US/Europe/China to take a stand. No shipping company is going to ignore those markets.

[1] https://road.cc/content/news/142312-london-ban-hgvs-without-...

So give it a several year phase-in period, and provide mechanisms to remove/permanently disable the systems.

I feel like I’ve seen this basic plot line before, once or twice.

Ending 1: the deadline approaches and nothing has been done, so the deadline is extended, or additional clauses are written to grandfather in the non compliant offenders (who are of course too big to fail).

Ending 2: they find a port that is near the port they want to visit, in a jurisdiction that doesn’t care, and then ship the last mile to the actual destination via other means. More costly and more pollution but technically in compliance with every law.

Ending 3: they learn to game the tests, so they meet the letter of the regulation but not the spirit of it. Much cheaper than actually reducing emissions.

So countries need to pressure each other’s neighbors into agreements where all of them refuse business with ships that do not follow such regulations?

This was a good strategy, but the US used it up with its idiotic War on Drugs.

That’s what has been done in this case which lead to cheating devices to be installed in the first place.

It’s very hard to near impossible to do or enforce all it takes is a country just by you that is willing to accept them.

People aren’t going to take a huge price hike and countries that are dependent on imports won’t ever enforce such requirements which would leave these vessels out there.

At the end of the day unless you are willing to fund a fleet of 1000’s of new vessels and or pay to upgrade existing ones the shipping companies won’t budge and you won’t ever be able to push them into a corner since the economic fallout would be catastrophic for you but not much for them.

>It’s very hard to near impossible to do or enforce all it takes is a country just by you that is willing to accept them.

You can set up treaties with your neighbors to enforce the same regulations. Also, if your country is sufficiently large enough, it's not really a concern because any savings from not having to follow the regulations will be wiped out by the increased cost in transporting the goods across the border.

You could also impose a tariff/charge on goods that transit through a neighboring country for no apparent reason (eg. China -> Mexico -> LA rather than China -> LA).

>People aren’t going to take a huge price hike

Source on the huge price hike? According to http://www.worldshipping.org/benefits-of-liner-shipping/glob..., the shipping industry contributes 183.3B to global GDP, and transports more than 4T worth of goods. Based on that, shipping accounts for approximately 4.5% of the cost of goods. Therefore, a 50% increase in cost because of emissions controls (very generous estimate) would only cause a 2.2% increase in the price of goods.

>and countries that are dependent on imports won’t ever enforce such requirements which would leave these vessels out there.

If it's announced years in advance, either shipping companies would adapt and get the vessels ready before the regulations take effect, or local manufacturers come online now that they're more competitive. No ships is ever going to be "stuck".

I don't buy your defeatism at all. The US certainly has the economic clout to make progress, and there's certainly a middle ground between doing nothing and expecting that every attempt to regulate externalities must be 100% effective and 100% enforced on every economic actor. At some (usually reasonably achievable) point, compliance becomes cheaper, or substitution occurs.