While you cannot put the blame on climate change onto iran alone (all of humanity has a part in it), the regime wants to deflect the blame conveniently onto climate change so as to absolve themselves of being responsible for their current water crisis.
So it's not really delusion, but irresponsibility and selfishness.
I’m only putting 2-3% of the global climate change as directly attributable to Iran. And their explicit attempts at preventing progress in stopping it.