This is possible, although hard, and is being done at a number of businesses. Most of my experience in this space revolves around working with this business in

This is possible, although hard, and is being done at a number of businesses. Most of my experience in this space revolves around working with this business in a consulting capacity a few years ago - https://truebearinginsights.com https://truebearinginsights.com. The short answer is that it gets easier when you focus on particular types and sizes of vessels. Ships are classified into size-based categories. For example, a "capesize" vessel is a massive dry bulk ship of 100,000+ ton (and often much bigger) carrying capacity. Since they are the largest ships, there are many fewer of them in the world, they are size-restricted on the ports that they can visit, it is only economical to carry particular types of cargo in these volumes, and because of the volumes, the ports often sit close to the source. Now, when you collect AIS data for capesize ships, you'll see trade lanes from Australia to China - these mostly carry Iron Ore from Australia's Pilbara region to steel/etc. factories in China (companies like Rio Tinto, BHP and FMG focus on this space). You'll see a similar trade lane from Brazil to China - this is also iron ore and led by a company called Vale. By analysing the trade lanes, cross referencing that with the raw materials that come out of each company, using Google Maps to investigate what the ships might be loading, etc., you can infer what the vessels carry and begin to extrapolate these routes. The same applies for many types of commodities, and is not limited to dry bulk. It can be easier in some cases to figure out the trading routes for ocean transportation of containers because the carriers often publish their routes in advance, but this obviously doesn't apply to the rail and trucking side of things, containers are often transported a fair distance before reaching a port, and containers will often be trans-shipped (i.e., transferred from one vessel to another at a hub port like Singapore), so it will be difficult to find the root nodes here. As you go down in vessel size, it gets harder. A small ship like a "handysize" could carry anything really - grain, potash, windmills, yachts (yachts often aren't insurable when crossing the open ocean so the owners typically have them shipped around the world instead). And there are tons of them. And their cargoes might be shipped long distances to the port. You can still find these nodes of course, but it will take a lot more work.