Effect of wind power on the global climate by decreasing kinetic energy of air Assume the hypothetical situation that all global energy is produced by wind power and instead of fossil fuel power etc.
Since every wind turbine decreases the kinetic energy of the air a bit, I am wondering if in this scenario there might be a global effect of this which may change the global climate considerabely. 
I.e. are there climate models which take this effect into account and what are the results?
 A: We don't yet know.
There is significant disagreement in the literature about how much wind energy we can harness without causing significant issues. Those disagreements are based on different assumptions, and different modelling approaches. Those differences occur because we don't have enough observations to be able to determine which are the better assumptions, and which are the better models.
The safely-harnessable amounts are thought to be in the range of terawatts (TW) to tens of terawatts. For context: global electricity consumption in 2016 was about 3 TW, and global primary energy consumption was about 20 TW, meaning global energy demand is probably somewhere around 12 TW (because so much primary energy is wasted in discarded low-grade heat, for example from power-station cooling towers). And, if we electrify everything, then the energy-efficiency savings of doing so would mean that even with ongoing global economic growth, global electricity demand probably wouldn't get much above 20 TW for many decades.
If you want to read about the disagreement, then two of the main protagonists are Mark Z Jacobson and David W Keith. I touched on it a bit in this related question over on skeptics.SE about global-scale wind power
Remember, when we do harness wind power, there are several other things that happen as a consequence, which have local, regional and/or global implications. Most importantly, we burn less fossil fuels, meaning less global warming and less consequential climate change. We have a huge amount of evidence to tell us that even if harnessing wind power at significant scale were to cause some climate change, it would be much less harmful than the damage that would be caused if we burnt fossil fuels instead.
(Note that this site also has a sister site dedicated to Earth Science, where you'll find one or two expert climatologists providing answers.)
