" (...) Given the preliminary nature of these results, it’s too soon to rule out a negative cloud feedback. MIT’s Richard Lindzen, for example, has proposed a mechanism called the Iris Hypothesis that could in principle produce a cooling effect. The idea is that as the Earth warms, the increase in humidity leads to a change in the balance between heat-reflecting cumulus clouds and heat-trapping cirrus in the tropics, with the former increasing and the latter diminishing. The result would be a strong counterweight to greenhouse warming — not enough, perhaps, to overcome it, but enough to make the warming minimal.

The problem, says Clement, is that 'there’s no empirical evidence for it.' (...)"
BY MICHAEL LEMONICK • AUGUST 30, 2010
https://e360.yale.edu/features/the_effect_of_clouds_on_climate_a_key_mystery_for_researchers

The last sentence: That is generally the problem with climate science: the empirical proof. If 0,04% CO² can't be used to prove the INCREASING heat trapping effect, why should it be a problem that the number of cumulus clouds will increase as the humidity on earth will increase?

The heat trapping effect of CO² is limited:
Dipl.-Meteorologist and Physist Klaus-Eckart Puls:The Achilles' heel of the climate models(10. IKEK)
http://globalskywatch.com/chemtrails/ubbthreads.php?ubb=showflat&Number=19728#Post19728


Also about clouds:
Spotty coverage: Climate models underestimate cooling effect of daily cloud cycle
http://globalskywatch.com/chemtrails/ubbthreads.php?ubb=showflat&Number=19711#Post19711