Dark Horse NY

I've been away for some time, as we've been working really hard on something quite exciting:

let me present to you the world's first ever global ocean drainage basin map that shows all permanent and temporary water flows on the planet.

This is quite big news, as far as I know this has never been done before. There are hundreds of hours of work in it (with the data + manual work as well) and it's quite a relief that they are all finished now.

But what is an ocean drainage basin map, I hear most of you asking? A couple of years ago I tried to find a map that shows which ocean does each of the world's rivers end up in. I was a bit surprised to see there is no map like that, so I just decided I'll make it myself - as usual :) Well, after realizing all the technical difficulties, I wasn't so surprised any more that it didn't exist. So yeah, it was quite a challenge but I am very happy with the result.

In addition to the global map I've created a set of 43 maps for different countries, states and continents, four versions for each: maps with white and black background, and a version for both with coloured oceans (aka polygons). Here's the global map with polygons:

I know from experience that maps can be great conversation starters, and I aim to make maps that are visually striking and can effectively deliver a message. With these ocean drainage basin maps the most important part was to make them easily understandable, so after you have seen one, the others all become effortless to interpret as well. Let me know how I did, I really appreciate any and all kinds of feedback.

Here are a few more from the set, I hope you too learn something new from them. I certainly did, and I am a geographer.

The greatest surprise with Europe is that its biggest river is all grey, as the Volga flows into the Caspian sea, therefore its basin counts as endorheic.

An endorheic basin is one which never reaches the ocean, mostly because it dries out in desert areas or ends up in lakes with no outflow. The biggest endorheic basin is the Caspian’s, but the area of the Great Basin in the US is also a good example of endorheic basins.

I love how the green of the Atlantic Ocean tangles together in the middle.

No, the dividing line is not at Cape Town, unfortunately.

I know these two colours weren’t the best choice for colourblind people and I sincerely apologize for that. I’ve been planning to make colourblind-friendly versions of my maps for ages now – still not sure when I get there, but I want you to know that it’s just moved up on my todo-list. A lot further up.

Minnesota is quite crazy with all that blue, right? Some other US states that are equally mind-blowing: North Dakota, New Mexico, Colorado, Wyoming. You can check them all out here.

Yes, most of the Peruvian waters drain into the Atlantic Ocean. Here are the maps of Peru, if you want to take a closer look.

Asia is amazingly colourful with lots of endorheic basins in the middle areas: deserts, the Himalayas and the Caspian sea are to blame. Also note how the Indonesian islands of Java and Sumatra are divided.

I mentioned earlier that I also made white versions of all maps. Here’s Australia with its vast deserts. If you're wondering about the weird lines in the middle: that’s the Simpson desert with its famous parallel sand dunes.

North America with white background and colourful oceans looks pretty neat, I think.

Finally, I made the drainage basin maps of the individual oceans: The Atlantic, the Arctic, the Indian and the Pacific. The Arctic is my favourite one.