[HN Gopher] Average color of each country (using satellite imagery)
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       Average color of each country (using satellite imagery)
        
       Author : xk3
       Score  : 298 points
       Date   : 2021-12-24 03:51 UTC (19 hours ago)
        
 (HTM) web link (eox.at)
 (TXT) w3m dump (eox.at)
        
       | toastal wrote:
       | The country of Taiwan, a solid dark shade of green
        
       | noveltyaccount wrote:
       | Interesting (but not surprising) how the color matches camouflage
       | used in each region.
        
       | hliyan wrote:
       | Surprised that much of Europe is green, considering that a lot of
       | their forests have been cut down for centuries.
        
         | seanmcdirmid wrote:
         | Grass is also green, lots of agricultural land come up as green
         | as well. Actually, Europe is still fairly forested (45%) on
         | average, so I'm not sure what other color it could be seen as.
        
       | qinfen wrote:
       | Using region in the title is more correct.
        
       | Stevvo wrote:
       | A nature lover's tip for Google Maps; old growth primary forest
       | appears a far darker shade of green than secondary forest. I've
       | found this very useful for finding good hiking close to urban
       | areas.
        
         | magicroot75 wrote:
         | This is such a great tip. Do you have any others? I personally
         | use Strava to find places to walk when I go to new cities. And
         | when I'm looking for a neighborhood to stay in a new cities, I
         | plot out all moderately expensive restaurants to use as a
         | heuristic for safe but not touristy neighborhoods.
        
       | qinfen wrote:
       | using region in the title is more correct.
        
       | thriftwy wrote:
       | They take those images during high summer, so no white countries.
        
       | phinnaeus wrote:
       | What's going on with the "Sentinel 2" text in the subheading on
       | the US colours by state graphic?
        
       | enriquto wrote:
       | These images don't make any sense to me. This map looks all black
       | except for the sahara desert. But the world map before averaging
       | looks mostly greenish.
        
         | guerrilla wrote:
         | Try on a different screen. What you're seeing as black is
         | green; there is no black.
        
       | thathndude wrote:
       | Expected to see, essentially, Camo, and wasn't surprised. But I
       | was surprised by the emphasis of green versus the yellow or brown
       | element.
       | 
       | Was worried that US was going to be "baby poop" yellow/brown.
        
       | gavinmckenzie wrote:
       | Very cool, but as a Canadian, I am disappointed that a more
       | detailed view of North America as a whole (Canada+US+Mexico)
       | wasn't included.
        
         | ahdh8f4hf4h8 wrote:
         | Agreed - I think it would be interesting to see it by
         | state/province (or even better some kernel smoothing) instead
         | of country. Country size is kind of arbitrary, as some
         | countries are very large and others are relatively small.
        
       | mkj wrote:
       | Time of year for image capture would be worth checking - some
       | places vary a lot. Interesting idea anyway.
       | 
       | Reminds me how Google maps changed to a more blue-green (pine?)
       | for forests which seems jarring for Australian forests or
       | woodlands.
        
         | OccamsRazr wrote:
         | Even more fun would be the same graphic produced as an
         | animation in the time dimension.
        
         | kevin_thibedeau wrote:
         | The brown smudge in Indiana/Ohio is definitely a seasonal
         | thing.
        
         | not2b wrote:
         | Yes, much of California is green this time of year and yellow-
         | brown in the summer.
        
           | eyelidlessness wrote:
           | Heck, same is true of Washington (the Evergreen State). I
           | think our average color is probably greyish mud?
        
       | yesenadam wrote:
       | Average colours of Australian states would be interesting. ..and
       | seems about the only part of the world left out so far, besides
       | Antarctica.
        
         | gnabgib wrote:
         | I guess people only pay attention to what they want to find,
         | but Canada and Mexico are missing (=North America with the US)
         | https://news.ycombinator.com/item?id=29673305. And the Asian
         | part of Russia https://news.ycombinator.com/item?id=29672321
        
           | yesenadam wrote:
           | I was talking whole continents. I did notice some other bits
           | went missing. "I guess people only pay attention to what they
           | want to find" - not sure exactly what you're trying to say
           | there, but it didn't feel good.
        
       | aflag wrote:
       | It would be interesting to see something similar at a city level,
       | it may be even insightful for some cities.
        
       | eruci wrote:
       | Interesting how Turkey and Azerbaijan have the same brown color,
       | while Georgia and Armenia which are in the same geographical
       | location, have a very different deep green color.
        
       | [deleted]
        
       | igitur wrote:
       | The red-brown of South Africa (and I guess Argentina and
       | Australia too) are basically midway points of their lush green
       | regions and dry desert regions.
       | 
       | South Africa is as green as neighbouring Eswatini (formerly
       | Swaziland) in the east and south coast and almost as arid as the
       | Namib desert in the far north west.
       | 
       | I suppose that's stating the obvious but still interesting. And
       | could probably add some comment about how this shows the dangers
       | of averages of any heterogeneous data.
        
         | jcmontx wrote:
         | You're right, averages in mid-sized and large countries are
         | pretty much meaningless
        
         | mastazi wrote:
         | One interesting fact is that the arid regions of Australia look
         | much more red than most other deserts (which look more yellow,
         | look e.g. at the Sahara or the Arabian Peninsula), this is due
         | to the high concentration of iron oxide in the soil of many
         | inland areas of Australia - in other words our sand basically
         | contains a little bit of rust :-D
         | 
         | Edit: a more scientifically correct explanation can be found
         | here:
         | https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200...
        
           | igitur wrote:
           | Does that mean if you have acid rain, it reduces back to
           | iron?
        
             | catlikesshrimp wrote:
             | Acid rain oxydizes. Reduction is the oposite chemical
             | reaction.
        
               | igitur wrote:
               | Ah, thanks. Then I misremembered my high school chemistry
               | from 25y ago. I thought rust (the verb) is oxidation and
               | that when you add an acid, it would be reduction (to get
               | back the iron).
        
               | kazinator wrote:
               | "Acid" is from Latin _acidus_ (sour, sharp, tart) by way
               | of French.
               | 
               | "Oxygen" is a word invented in 1777 by Antoine Lavoisier,
               | from the Greek _oxys_ (sharp, acid): same thing!
               | 
               | Lavoisier also invented "oxide" from ox(ygene) + (ac)ide.
        
               | barrkel wrote:
               | Acid / base and oxidize / reduce are mostly orthogonal.
               | Acid / base is about moving around protons while oxidize
               | / reduce is about moving electrons.
               | 
               | There's a table here: https://www.vedantu.com/question-
               | answer/acid-base-reactions-...
        
         | LeifCarrotson wrote:
         | I think the mode (after coercion from millions of colors to a
         | smaller number of buckets) would be more meaningful than the
         | mean.
        
       | Jon_McLoone wrote:
       | You can acheive the same result in three lines of Wolfram
       | Language...
       | https://community.wolfram.com/groups/-/m/t/2431480?p_p_auth=...
        
         | idealmedtech wrote:
         | A lot of the complexity of the python code is hidden by the
         | Geo* methods you have here; a more representative comparison
         | would show how those methods are implemented (eg with the shape
         | files).
        
           | [deleted]
        
           | Jon_McLoone wrote:
           | But that is the point of the Wolfram Language. If you are
           | doing work with computation or data, it should be just built-
           | in.
        
             | Jon_McLoone wrote:
             | Actually, handling .shp files is also just built-in...
             | https://reference.wolfram.com/language/ref/format/SHP.html
        
           | aflag wrote:
           | There is a lot of complexity hidden in the R functions as
           | well. The reason of using higher level languages with
           | comprehensive standard libraries is exactly to abstract these
           | things away. So, I think it's fair to say that, for this
           | particular problem, wolfram language is better suited.
        
         | Enginerrrd wrote:
         | That's actually astonishingly impressive to me.
        
       | robga wrote:
       | I've always wondered what the average colour of the web is.
       | Probably close to light gray. Maybe Facebook gives it a blue
       | tinge. Dark modes have complicated the question.
        
         | OJFord wrote:
         | It'd be particularly fun to see that change over time -
         | probably very much light grey early on (black text on white or
         | near white or patterned whiteish as was popular) but
         | darker/more colour as 'webapps' became more prominent and took
         | over the whole screen more.
        
       | code123456789 wrote:
       | Author forgot the Asian part of Russia, it's included neither to
       | Europe, nor to Asia. But it's still on the general map of the
       | world. Anyway it would be green.
        
       | kzrdude wrote:
       | One can see the same thing as in regular satellite maps: for
       | example that Spain is the odd color out in Europe. Much more
       | arid, even if it's not a desert.
        
       | SideburnsOfDoom wrote:
       | So the "Emerald Isle" of Ireland is basically the same green
       | colour as the UK.
        
         | anotherhue wrote:
         | Pretty much. Remember how close they are geographically. IANAG
         | but the gulf stream is probably the only significant
         | difference. Also, they probably should say GB not UK.
         | 
         | https://www.bbc.co.uk/staticarchive/faa977f45fd35ea2f898aaf8...
        
       | moontear wrote:
       | Very nice and beautiful! Would print and put on my wall
       | 
       | Is the ,,A" from Average in the poster set apart a bit more
       | (letter-spacing) or am I seeing things?
        
         | gpvos wrote:
         | That can happen if you have an A and a v next to each other and
         | no kerning. Although "from" in the (cursive) line below does
         | seem kerned.
        
       | divbzero wrote:
       | It would also be cool to see the average color of each body of
       | water (ocean, sea, lake...)
        
       | silexia wrote:
       | Note that China is gray with pollution. They claim to be reducing
       | pollution, but as a dictatorship it's probably just lies.
        
       | obblekk wrote:
       | The map design itself is really beautiful. I wonder if there's a
       | mobile app that lets me skin google maps in this kind of
       | aesthetic?
        
       | Gatsky wrote:
       | Surpsied at how red Australia is... although we are trying to
       | lighten our complexion by exporting all that iron ore to China.
        
         | jaza wrote:
         | It ain't called The Red Centre for nothing.
        
         | tomxor wrote:
         | I think it's fitting, feels like the right colour for it's
         | uniquely ancient geology.
        
       | doctorhandshake wrote:
       | It seems FTA that the 'average' color is found by resizing the
       | color information within the bounds in question to 1:1 and then
       | using that color to fill the bounds. I'm not sure but that seems
       | to be an important algorithmic element of this process that is
       | almost completely delegated to a side effect of an image library
       | and not really discussed in the context of this write up.
        
         | lgeorget wrote:
         | I also routinely make visualizations of geographic and weather
         | data (including satellite imagery) as part of my job and it
         | doesn't surprise me. Once you've 1) acquired the data you need
         | (in this case, we're talking about images of countries without
         | clouds and corrected for exposure across the Earth) and 2)
         | fixed your data (because it's never in the shape you want, or
         | the map projection you need), the core of the algorithm can
         | seem pretty trivial sometimes, especially because R and GDAL
         | come with a very large set of ready-to-use algorithms (and I'll
         | never thank the creators of their respective libs enough for
         | that).
        
         | aardvark179 wrote:
         | There will be a considerable amount of averaging and re
         | sampling before the final resize. Depending on shape of the
         | region and how samples outside it are handled you may see
         | considerable variation in the results.
         | 
         | What I would be interested in is how much the colour would
         | differ if another colour space were used. I wouldn't expect a
         | huge change in the imital re projection as adjacent samples are
         | likely to be close in whatever colour space is used, but I
         | think it might change some of the average colours.
        
         | maxerickson wrote:
         | The color is seasonal also. Michigan is green in the summer,
         | loses that in the fall, gets whiter in the winter.
        
           | tomsmeding wrote:
           | I think that most places on Earth get whiter in winter. ;)
        
         | pieterhg wrote:
         | FTA?
        
           | taejo wrote:
           | From The Article
        
       | esemor wrote:
       | I always knew my home country was dark but, geez...
       | 
       | / Greetings from Sweden.
        
       | shrx wrote:
       | I don't see it mentioned in the article, but I suppose one of the
       | equal-area projections [0] should be used for calculating the
       | average color data.
       | 
       | [0] https://en.wikipedia.org/wiki/Equal-area_map
        
       | authed wrote:
       | I'm surprised that the US is that green with all the desertic
       | areas...
        
       | Enginerrrd wrote:
       | Not unexpected per se, but I love how closely this tracks with
       | various camouflage colors in active use.
        
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