When are water vapor pressure and saturation vapor pressure the same?

Water vapor pressure in Amazon and Arizona areas?

• 1) Why does the Amazon have higher water vapor pressure of air than the Phoenix Arizona? -I was thinking because the amazon is a tropical region with lots of precipation with less seasonal rain variation, and phoenix arizona is because its inland area? 2) If there is lifting mechanisms involved, will the Amazon rainforest with relative humidity 83% or Arizona with relative humidity 27% produce clouds on this day? 3) Which of these places are experiencing saturation and why do you think so? Antarctic relative humidity 50% SF relative humidity 100% Phoenix relative humidity 27% Amazon basin 83%

• Answer:

  Jennifer, The amazon is warmer and wetter than Phoenix. therefore the vapor pressure is higher in the amazon than in Phoenix. More clouds are likely in the Amazon as the air will be more likely to reach the lifting condensation level in the Amazon than in Phoenix due to the stronger convection. Finally saturation occurs when the humidity is 100% and so the answer to 3) would be SF.