there is not such a direct correlation between clouds and average humidity in the atmosphere. on one hand air could be oversaturated with humidity and you still may not see a cloud, because there are no starting clusters for kondensation/crystallisation. you could on the other hand have cloudformation with relatively little humidity if there are starters around (the german word is Kondensations-/Kristallisationskeime, i dont know what that is in english). such starters could be dust (St. Helen) or allready crystallised water or ions. a way to manipulate the weather is to ionize airmolecules in the upper layers of the atmosphere to cause cloudformation. it is also possible, that the atmosphere carries overall less water, but there are more clouds, because the water is accumulated in cold regions of the atmosphere, while the lower, warmer regions are relatively dry.i dispute, that there is more watervapor in the atmosphere. the earth it not warming, it is getting colder by the day. ever since it came into existence as a ball of melted rock billions of years ago it has been emitting more energy than it absorbed from the sun, leading to a more or less solid crust, that is still emitting energy into space, which makes a net loss of heat. the thin layer we live on is fluctuating in temperature all the time, the reason for which is mainly changing solar activity and sometimes in the history of our planet due to geological activity, as the earth's volcanoes produce a lot more CO2 than the puny human civilisation of today.