FRACTAL TERRAIN - GREENHOUSE VALUE
NeonKnight
Traveler
Trying to find an answer for this, and well - not having much luck.
Under World Settings -> Temperature I can adjust the Albedo (easy google search clarifies low albedo the more light absorbed vs a high albedo more light reflected)
Light pretty self explanatory as # of suns
And then there's Greenhouse. :(
if I'm trying to make a Tropical World is Greenhouse Higher than 1.1 or lower?
if a more Arid world, is Greenhouse Higher or Lower
Thanx for any input!
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The temperature model is pretty straightforward:
Light is amount of light coming in
Albedo is the amount of that light that's absorbed into the surface
Greenhouse is the amount the absorbed light that stays on the world (reflected back by the atmosphere from the surface)
Unfortunately, Greenhouse is a non-linear parameter, meaning that changing it by X amount more will not have a Y amount of change in temperature, but rather some exponential amount of X.
Those three parameters are a very simplistic model of temperature that doesn't take into account a whole lot of effects (atmospheric composition and density, for example, is mostly accounted for by the Greenhouse parameter and general world appearance [oceans, clouds, amount of surface ice] is mostly accounted for by the Albedo parameter).
Tropical and Arid are mostly functions of rainfall rather than temperature. FT's climate results are approximately a function of a lookup table according to average annual rainfall and average annual temperature. If you'd like to see the lookup table, use Map>>Show Image Climate to show the Alternate Climate Coloration dialog. Moving the mouse around the central area will get you an idea of what FT believes corresponds to "tropical" is roughly in the temperature range of 65F to 100F with the various types of "tropical" distinguished by rainfall.
A point of interest: FT uses something very close to the Whittaker climograph with the exception that it's extended to a full rectangular area in ways that don't occur here on Earth.
A critical part of a good climate model is heat transport by ocean and atmosphere currents as well as heat and moisture transport by atmospheric currents. FT doesn't model these at all, making it a Bad Climate Model. I always hoped that people would paint in things on the rainfall and temperature editing channels, but it hasn't happened much.
The short version is that the easiest way to raise the base temperature to tweak Light upwards to get the general amount of tropical that you want and then adjust rainfall base amount to get which kind of tropical you want.