Global warming

[Laser77]

Did anybody get the global warming to climax?
I just let pollution spread all over the world enjoying several terraform effects.

When you have a large population and sell all your recycling centers and mass transits pollution will start.
With the first dirt on your map, right, not on your screen, the red sun appears. If you do not clean the mess up, the sun symbol will change colors to pink, yellow and finally white. Now is your last chance to remove the dirt. If you keep on ignoring the warnings of your scientists your global warming begins to influence your map.

Several plains will change to desert
Some grassland will change to plains
Not very exciting so far

In the next cycle coastal plains, grasslands and even deserts turn to swamp - now it is getting interesting. Some forests may turn to plains and coastline forests turn to djungle

What I would have expected from a global warming would usually be the disappearing or changing of arctic fields to tundra and tundra to plains. I would have expected that the coastline would turn to water. But that did not happen.

At least not in 6 cycles of pollution based global warming including an ice cap melt down. I will now clean the mess up and see which places on the earth map take advantage from the effects.
I can already see that the whole coastline is swamped, which could be interesting when you play on dry small islands. Remember that coastal forest turn to jungle and even deserts turn to swamp sooner or later. I will try on polluting the Earth map. Have nice swampy Saudi Arabia and North Africa coast already and a moist Mexico. All Indonesia is wet and there’s swamp lining the silhouette of Australia. Sibirian forest on the coast turned to djungle even with gems.

Most disappointing there is ABSOLUTELY NO EFFECT on arctic and tundra fields by now.

 

[sjongejonge]

Global warming appears like a pattern, just like grassland with shields.

For grassland with shields it is a zig-zag pattern from north-east to south-west.
Pollution makes diagonal changes to the landscape from north-east to south-west.

More diagonal lines get added with every global warming until the whole world is swamped. Except for icy squares.

 

[Laser77]

Good to know. Anybody knows if there is an impact on mountains/hills? The most probable effect did not appear, meaning changing of arctic and tundra squares. Now what about the less probable case?

 

[sjongejonge]

Mountains/hills also don't get swamped.

 

[Valen]

I've only seen the first 1 or 2 rounds of global warming. Grassland turns to plains and plains to desert.
So you're saying I can wait it out and those deserts will turn to swamp? Awesome.

 

[tupi]

Thanks you for the algorithm, sjongejonge. I tested it and it's indeed this simple. Previously I thought it was impossible to guess it just from observation, so I didn't even tried. Only problem remains - which coastal squares are affected and why? So if a square has 1 ocean or swamp near (not diagonally), let's call it 1/4 etc. So I think in first warming some 4/4 and some 3/4 squares are affected, in second - much more squares are affected but still only 4/4 and 3/4, and in third and fourth warmings 2/4 affected too and in fifth even some 1/4 are affected.

I implemented it in civgen with some approximate swamp/jungle generation. Hope somebody will implement it in CivOne too.

So to clarify:
offset = (global_warming_count*3)%8;
(global_warming_count for the first warming is 0 and so on)

check every square on the map
and if (x%8 == (offset+y)%8) is true:
change grassland to plains
change plains to desert
change forests to plains

also some coastal grasslands, plains and deserts can transform to swamps and some coastal forests can transofm to jungle (NOT only in affected lines) but certain algo is not clear

 

[tupi]

I reverse engineered it today. There's no randomness in appearing of new swamps as I thought before. Let's see...

For first warming, number of global warmings used here is 0, for 2nd it's 1 and so on.

You got newspaper message "Global temperature rises! Icecaps melt.\nSevere Drought."
Then game loops through every square of world map (column after column, loop for X before loop for Y for some reason) and:

if terrain type is desert, plains, grassland or forest, then...
count number of adjacent ocean squares (including diagonals)
if (adjacent_ocean_squares >= 7-global_warmings)
then change forest to jungle and other terrains to swamp, delete mine and irrigation (only real, not visible) and redraw this square, if it's visible to the player
else...
if remainder of division (11*x+13*y) by 8 is equal to global warming counter, (i.e. if ((11*x+13*y)&7 == total_warmings))
then if terrain is desert or plains, change it to desert, else change it to plains; and redraw the square, if it's visible to the player

As you can see, during first warming a square needs at least 7 ocean squares near it for 'flooding' . During second one it needs 6 or more. In 8th warming, swamp/jungle will appear even if there's no ocean nearby, so it will cover almost entire planet.

X coordinate for warmings (for Y = 0): 1st: 0, 2nd: 3, 3rd: 6, 4th: 1 5th: 4 6th: 7 7th: 2 8th: 5 after that they will repeat themselves. Lines are going from NW to SE.

Current and absolute land values are NOT re-calculated after the event, so you can see some strange AI behaviour. Visible improvements also don't updated, so you can see, for example, irrigation on swamp (which actually was destroyed).