Tuesday, July 19, 2011

Global precipitation fails to obey theory of global warming

Alarmists frequently claim global warming causes increased atmospheric water vapor, and thus allegedly results in increased precipitation, floods, and even snow. However, a plot of all available worldwide data for the CPC Merged Analysis of Precipitation shows there has been a slight decrease in global precipitation over the past 30 years of global warming. In addition, there has been a decline in extremes of precipitation. Satellite and radiosonde data also show, contrary to the theory, that atmospheric water vapor, relative and specific humidity have all declined over the available instrumental records. Another basic tenet of global warming theory bites the dust?
Time series of all available worldwide data for the CPC Merged Analysis of Precipitation. Home site at NOAA for the CPC data.


  1. If the observed warming is caused by increased solar shortwave getting into the oceans then the equilibrium temperature for the entire system will rise (that temperature being set by the oceans and not by the air) and there will be a decline in rainfall and humidity during the process because warmer air holds more water vapour.

    If the observed warming is caused by more GHGs in the air then the extra downwelling IR fails to get into the oceans so the equilibrium temperature for the entire system does not rise (the oceans would hold the air temperature down) but instead evaporation, humidity, condensation and precipitation would rise.

    The graph is evidence that the recent warming was more likely solar induced than GHG induced.

    Stephen Wilde.

  2. Stephen Wilde,

    Appreciate your salient analyses which always make sense

  3. A global precipitation is much harder to calculate than a global temperature. That said, I would ague that the reason you are seeing the precipitation drop is because the temperature has been dropping since 1986. Perhaps not globally, but that has certainly been the case in the wet climates such as BC. It seems to that the precipitation follows about 4 years later. See link.

    1. Oops, I have forgotten the links...

      graph: http://forums.castanet.net/download/file.php?id=15698&mode=view

      thread: http://forums.castanet.net/viewtopic.php?f=22&t=51471

      ~ Glacier