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Why it is misleading to claim that maps prove ships are stuck near China?


If you’re a regular consumer of shipping-related social media, you’ve probably recently seen a few maps showing the coast of China with a mass of small dots representing ships. Social media posters claim that the ships are stuck there because of the COVID lockdowns in China. They often also claim so that ships are being held up for more nefarious reasons. We won’t discuss these other reasons, they’re just nonsense as far as we can tell. We will focus on the shipping side of things.

Look, there are clearly supply chain issues caused by the COVID lockdowns. But there aren’t hordes and hordes and hordes of ships stuck on the Chinese coast. For a given definition of “normal,” the situation is, well, pretty normal.

What’s going on?

You’ve probably seen something like this. It’s a map of eastern Asia, and, specifically, what is floating on the seas around Asia.

All tracked vessel traffic on the seas around East Asia

a representation of various kinds of marine craft and assets off the Chinese coast. All of the graphics in this article are screen captures, that were captured within a few minutes of each other. Social media commentators claim that the are ships somehow allegedly “stuck” off China. Source:


What you’re looking at here is a graphical representation of various floating things (ships mostly) on the sea off east Asia. The positions of the floating objects were live and current at the time of writing.

Various social media commentators of various kinds incorrectly claim that these maps show ships somehow “stuck” off the Chinese coast, usually they claim it is because of Chinese COVID-control policies and / or there are allegations that some kind of nefarious activity is going on.

Let’s really think about what we’re looking at.

Everything that floats

Floating on the sea are a variety of things. These floating things include ships.

And also tugs. And yachts. And fishing vessels. And buoys. And a wide variety of other things that float.

A great many of these things have tracking devices on them, which anyone with a tracker can pick up. So what you’re looking at is the digital representation of a great many things that are afloat.

Let’s look at the geography. Well, clearly, we’re looking at the sea space around China, and South Korea, and Japan. North eastern Asia is the centre of world manufacturing. North east Asia is also a relatively prosperous part of the world and it has a huge population.

Manufacturing+population+income = high volumes of ships.

High volumes of ships = high volumes of other watercraft (tugs etc) and floating nav aids.

So what we’re looking at are huge volumes of tracked, floating watercraft in a region of the world that is known for, and quite logically would have, huge volumes of tracked, floating watercraft.

OK. So if we get rid of the non-freight carrying watercraft, the map looks like this:

Freight Carrying vessel traffic on the seas around East Asia

Graphic: sea-freight traffic on the seas of east Asia. Source:












Although it is a bit less intense, the map is still heavily marked. But that should be expected in a heavily trafficked sea area. It’s also a huge sea-area. From the top of North Korea (as pictured on the map above) south to Manila, the Philippines, is about 3,050 km (1,900 miles) or so.

Comparators: the Med and the Gulf

Let’s have a look at some comparators, namely the Mediterranean and the Gulf of Mexico.

Europe and East Atlantic

Comparator: Europe / Mediterranean. Portugal to Crete is about 3,000km. Graphic:













Gulf of Mexico

Pictured the Gulf of Mexico. From Matamoros (Mexico, on the Mexico / US border) to a point just east of Puerto Rico is about 3,000km. Graphic:

So both spaces have a lot less traffic than North Asia. But this is expected. And both graphics show that having large volumes of freight carrying ships in a given area isn’t exactly unusual.

We can see this better if we zoom in. We’ll now look at the space around the two top container ports by volume, namely, Shanghai and, for comparison purposes, Singapore.


Pictured: a close up of the traffic at Shanghai, China. Note the scale (10km or 5mi) bottom left. Graphic:


Pictured: a close up of the traffic in the seas around Singapore, south east Asia. Note the scale (10km or 5mi) bottom left. Graphic:

So, once again, what are we looking at?

Green shapes indicate cargo ships of various kinds that are not tankers. Red indicates tankers.

By now you have probably noticed that the icons representing ships have different shapes. A key thing to note is that, in all the maps above, the round circles represent ships that are not moving. The arrow-like shapes indicate ships that are moving and the direction that they are moving in. As you can see there’s a lot of stationary ships at both Shanghai and Singapore.

The fact that some ships are stationary and others are moving is another key reason why many of the maps you see on social media are misleading. One of the reasons we’re using the maps is that, unlike many of the maps you see on social media, this system distinguishes between stationary and moving ships. Many of the social media maps just show icons that, it is alleged, represent the positions of ships. Even if that claim is in fact true, it’s highly misleading if you don’t know whether the ships are moving or not.

A superficial eyeballing of the two graphics would tend to suggest that there are maybe about as many stationary ships at Shanghai as moving ships and that possibly, in Singapore, the stationary ships outnumber the moving ships. Maybe.

Regardless of the exact count, it is clear that stationary ships do not massively outnumber the moving ships at Shanghai and that there is a similar situation at Singapore. If ships were getting “stuck” off China because of a lockdown in China then we would expect to see a massive number of stationary ships compared to ships underway at Shanghai. In contrast, Singapore would likely show what it does now: large numbers of stationary and moving ships.

But we see more or less the same situation at both ports. That would tend to indicate that ships are not getting stuck off the coast of China. The comparator, Singapore, would also tend to show that having large numbers of ships stationary off the coast is not something that is confined to China. It could be argued that the Singapore situation suggests (depending on port) that having large numbers of ships stationary off the coast can be regarded as “normal”.

So the various social media commentators’ general allegations that there is a supply chain crisis because ships are somehow getting stuck off the coast of China would be appear to be unfounded by evidence.

Details are lost… or revealed… depending upon scale

A final problem with the graphics presented by many of the social media commentators is that you can’t really see what’s going on because the graphics cover such a huge sea area. A lot of the detail is obscured. In the first graphic presented at the top of this article, the scale is about 500km and we can’t even see Shanghai, which has disappeared under horde of icons. Even at the 10km scale there are icons-on-top-of-icons.

Let’s (metaphorically) squint a bit and see what we can see at the 1km scale. Once again, green represents freight ships (not tankers) while red icons represent tankers.














Pictured: freight traffic at Singapore, near the airport, 1km scale. Source:

As can be seen, close to one, specific, part of Shanghai, there are are lot of vessels that are underway (arrow-shaped markers). So, on maps that don’t distinguish between stationary ships and moving ships, it will simply look like there’s a lot of ships nearby a port. But it would be completely wrong for a viewer of the map to jump to the conclusion that there are ships stuck by the port merely because there are lots of ship-icons there. The 1km-image showing (above) showing the space off Shanghai airport is a good example. There are about 54 ships underway, of which about six are stationary.

Meanwhile, in the second of the 1km-image maps, which show an area close to one, specific, part of Singapore, there are a lot of vessels that are stationary. It is impossible to see this level of detail unless you really zoom in, which is yet another reason why the maps you may see on social media are misleading.

The two close-up maps are also misleading by themselves. Different close up maps of different parts of the areas around Shanghai and Singapore will show different situations. With a bit of searching it would be easy to find lots of stationary ships around Shanghai and lots of ships underway around Singapore. The fact is, ports may well have a lot of ships nearby that are underway and a lot of ships that are stationary.

There’s a few reasons for this. The first is because of the fundamental nature of ports: they’re places where ships go to load and unload cargo so, logically, some ships will be stationary and some underway.

Ports also have “anchorage” areas around them where ships go and wait for various reasons. Waiting to go into their turn at berth is one reason. Another, is that in places like Singapore, it may be a physically sheltered area with little adverse weather at the equator. Ships can safely wait there until they’re needed to carry cargo.

What type of cargo ship, exactly?

Another point to note is that, if you click on the icons, it may tell you what type of vessel it is. A lot of the icons around Shanghai represent river-shipping cargo ships. China has massive (long, wide and deep) navigable rivers, particularly the Huang He (Yellow River) in the north, the Yangtze River in the centre, and the Zhu Jiang (Pearl River) in the south. These rivers enable vast movements of river cargo ships, so many of the icons that will be seen in the rivers, the river mouths and near the coast of China on ship tracking systems are river cargo vessels. They may be small but there are so many of them.

The two close-up images also show that there’s a lot of detail that can be missed as the icons pile on top of each other when you are looking at a bigger scale / from further out.


Anyone trying to interpret meaning from graphics like these above needs to know a little bit about shipping, operational matters, patterns of trade, and patterns of ship movements around ports to understand why a set of ships may be stationary, or underway, and to draw reasonable inferences from the graphics.

So there is a two-fold conclusion:

  1. be sceptical of maps with lots of dots that purport to show some kind of supply chain crisis;
  2. you really can’t believe everything you see or read on social media!

This article is shared by courtesy of Shipping Australia Limited – –  The major focus of Shipping Australia, as a peak industry body, is both to promote and advance the interests of shipowners and shipping agents in all matters of shipping policy, environmentally sustainable practices and safe ship operations.

For more articles about shipping traffic, click here


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