Have you noticed the amount of maps with black or dark backgrounds that you see online these days!? It is a common trend to use light-on-dark to create a striking visual hierarchy and most of the maps that go viral tend to have adopted this style. I’m sure that has something to do with the aesthetic appeal and the initial impact of these maps. Using a dark background leaves room for many light colours which can create great contrast for any overlays that immediately become the maps focal feature as they often appear to glow.
Here are some examples:
The majority of traditional maps use white (or similar) as the background colour and this can be largely attributed to the distribution mechanism which would usually be paper. The majority of paper is white and it also brings cost savings with regard to ink usage – it wouldn’t be wise to smother a sheet of white paper with dark ink!
With modern mapping technologies and the internet as the main method for sharing maps, any print concerns that restricted design decisions in the past are no longer an issue. Many maps these days will never be printed, just pored over on PC screens and mobile devices.
There is something cool, aesthetically pleasing and eye-catching about dark maps.
It may just be that this bold technique portrays a certain element of rebellion – a refreshing break from tradition.
cartoblography 
Ok, trending & aesthetic apeal, initial impact… I’ve got your point. But are the maps effective also… You dit not write about that. If one uses black as background, remember that 1) the (PC/Laptop) screen contrasts very much with the surrouding. To operators (decission makers) that is less nice to view, because no-data pixels (=the backgound) should NOT have to much contrast for happy viewing. 2) (and more important). Using black at the backgound changes the direction of how to achieve visual hierarchie with color. To my opinion / experience, the cartographer has to use much bigger point, en much whiter points than he’s used to. The range of effective colors that he can choose, is diminished, to my opinion. Differences in color between serveral diverent (light) points on black are more difficulte to distinguish than diverences between colors that are (relativly) dark points on a white background. Maybe for simple maps, there’s no problem, but, the more complex the data or the legend, the less effective a black background will be. I Think. 3) IF one uses a black background, the dark pixels of the map also must NOT contrasts with the background of the rest of the website/computerscreen. That’s because the background must appear as an non-data-pixel, otherwise, the outline of the map (instead of the data) wil automattically get to much attention of our brains. So if using it in a website, and it is not a full-page: use it whithin a black website (section). If effectiveness of readablility of the map is not the goal (which should be very rare), then, maybe, there is no problem of using those black maps. I guess, marketing (for the map, cartographer or a product or website) goals will be the only valid reason for choosing black, saying loud: “Look at me! Look at this funny map…”.
Hi Tjeerd,
Thank you very much for your thoughts on this subject.
My intention for this blog is not to critique as such but to highlight different aspects of cartography and showcase some great maps.
I would agree that using a dark background is not relevant for every type of map and in some cases would be a bad design choice. I don’t agree though that marketing goals are the only valid reason to choose this approach. Part of a cartographers (and data visualisers) job is to make their maps engaging (without grabbing the viewers attention the message won’t be delivered successfully) so although using a dark background does add a slight gimmicky edge I think it is still valid and justified. I also believe that the ‘gimmick’ value will wear off as more maps like this are made and dark maps will become ‘the norm’.
Charley