Climate ? probably you mean weather. It can be programmed as we wish, if we know how and when thermals form. On the website that lists the worldwide thermals
https://thermal.kk7.ch/ they give different maps for season and daytime, so this can be implemented by just copying the data from the site. Also they give "probability" of each thermal hotspot to occur for the given season and daytime. This is also easy to program..just switch it on and off (gradually) with that probability and for a time proportional to the probability. So if you're lucky you will find the thermal to be active with the probability given by the real world thermal database. Weather dependence ? It seems that gliders fly only with "nice" weather so if outerra weather gets rainy or too windy I will probably switch off all thermals, as you're not supposed to do glider flights under such weather conditions. .
..unless you want to fly in a Hurricane !! which is also some kind of thermal
So I can implement a range of windspeeds, turbulence, etc...for which thermals will be active.
Any other knowledge input or suggestions are welcome , as I am practically ignorant in this matter ,and just report what I have understood so far.