Increase in concentration of atmospheric water vapour

Nature 
As the climate becomes warmer the concentration of water vapour in the atmosphere increases. Water vapour is at present the main factor contributing to the entrapment of infrared radiation from the Earth's surface. Increases in water vapour should therefore significantly enhance global warming. Such positive feedback could bring about a runaway increase in global warming.
Counter-claim 
Such a runaway effect would only be possible in a climate many ten's of degrees warmer than that prevailing.
Aggravates 
Strategy(ies) 
Type 
(E) Emanations of other problems