The average
atmospheric water vapour content has increased since at least the 1980s over land and ocean as well as in the upper troposphere.
The annual peak in
atmospheric water vapour content occur usually around August - September, when northern hemisphere vegetation is at maximum transpiration.
To claim that the entire system of atmospheric temperature moderation has been described by the fluctuations of atmospheric CO2 content while excluding the other obvious factors such as
atmospheric water vapour content, solar flux and orbital mechanics is just nonsense.
«The far north has indeed been behaving bizarrely in Nov / Dec 2016, setting many new records for temperature, sea ice extent,
atmospheric water vapour content, and Arctic amplification (the difference in temperature between the Arctic and northern mid-latitudes)»
In a warming world,
atmospheric water vapour content is expected to rise due to an increase in saturation water vapour pressure with air temperature.
Not exact matches
When the atmosphere cools again
water vapour content declines and the
atmospheric greenhouse effect weakens.
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Water Vapour (WV) does not mix evenly in with the other gases and
atmospheric WV
content varies from location to location but I believe it is estimated to be around 4 to 5 %.