Here are two similar articles/blogs by the same OP who proposes that agricultural irrigation is the gorilla in the room with respect to Global warming.
We have damned(sic) thousands of rivers and pump billions of gallons of water from aquifers, most of which ends up in the atmosphere in the form of water vapor through transpiration and evaporation.
Water vapor is the primary warming agent in the atmosphere.
According to the OP's calculations we are adding 12 cubic kilometers of water per day (more than the average flow of the mighty Amazon) to the atmosphere which translates to 314 tera watts or approximately 21 times as much energy as we currently use globally from all energy sources combined.
http://gwhunta.gnn.tv/blogs/22032/Agriculture_and_Agricultural_Irrigation_is_the_Cause_of_Anthropogenic_Warming_of_Earth_s_Climate_Systemhttp://gwhunta.gnn.tv/blogs/22104/Global_Warming_Think_Again_or_For_the_First_Time_Think?r=5