Quote"If shipping was a country, it would be the sixth-largest polluter in the world," says Nerijus Poskus of the shipping technology company Flexport. "About 3% of global emissions are released by ocean freight shipping."

One solution: hydrogen.

https://www.npr.org/2019/07/16/716693006/the-dawn-of-low-carbon-shipping?utm_source=twitter.com&utm_campaign=npr&utm_term=nprnews&utm_medium=social

For every day THE SHIP is in the harbor, the ship's smokestacks may be spewing as much nitrogen oxide into the city's air as 12,500 cars, as much as an oil refinery.

https://www.seattlepi.com/local/article/Air-pollution-from-cargo-ships-stirs-growing-1134930.php

My boys helped design this system in the Port of L.A.
http://advancedemissioncontrol.com/