It's important to remember that there is no baseline state for our atmosphere; that is, there's no reason why storms and droughts and such could not be much, much more severe than they are currently. By throwing a bunch heat into the system, we could very well tip our atmosphere into a much more inimical mode....
I'm not sure what you mean by "baseline state," but you could say that the planet has evolved to draw CO2 out of the atmosphere and compound it underground as fossil fuel, along with the energy stored in it.
It has also evolved to spread tree/plant growth over dead rocks and sand wherever possible so that the abundant green light of the sun is reflected away while animals and soil get food to digest/compost and thus turn into oils and other sediments that build up over time to various ends.
If we keep allowing greenhouse gases to build up, ever smaller creatures will take over. Insects, molds, and bacteria might be the only living organisms at some point. Eventually the greenhouse gases will feed into the natural ecological cycles in some way and the climate will begin stabilizing.
New species will gradually evolve and diversify from those that survive the climate instability; though it may take many millions of years.