Monday, July 18, 2011

Rising CO2 causes unprecedented decrease in worldwide drought

Update: a commenter below has noted that the Palmer Drought Severity Index uses an inverse scale, with more negative numbers reflecting an increase, not decrease in drought. The commenter appears to be correct and I apologize for the misinterpretation. Still unexplained, however, is why the claimed increase in atmospheric water vapor due to global warming would cause increasing drought; see comments below.

A plot of the worldwide data for the Palmer Drought Severity Index shows that there has been an unprecedented decrease in world drought severity over the past 30 years.

[The title of this post is facetious about CO2 being the cause of the decreased drought - see comments below]


  1. It is somewhat provocative of you to say that the rise in atmospheric CO2 caused the decrease in droughts; but, I have no doubt that you wished to be provactive. That being said, this is an extremely interesting post, everyone should read it. It certainly refutes the idea that increase in atmospheric CO2 is likely to be accompanied by an increase in the number of droughts

  2. Just to be clear, the title is facetious play on the tendency to blame every change in climate and weather on rising CO2, without any supporting evidence.

  3. "The title of this post is facetious about CO2 being the cause of the decreased drought"

    Haha! I came to this site just to yell at you for your title because I thought it was serious :). It's the kind of thing I'd expect to hear from James Hansen. Well, the opposite, but of the same quality.

  4. It would have been more in keeping with Skeptic integrity to have said "correlates with" in the title. We have the science on our side - there is no need to stoop to warmist tactics

  5. CO2 correlates with anal retentive... oh never mind.

  6. In the Palmer drought severity index a negative number means more drought. A positive number means more than average wetness.

  7. Scott S,

    Thanks for that correction - you are in fact correct, my interpretation was wrong, I apologize and have added the correction to the body of the post.

    However, I await an explanation as to why the warmist refrain that a warmer atmosphere holds more water vapor and causes more precipitation could be compatible with an increase in drought.

    1. don't know if you will receive this but it appears that the hadley overturning cell that moves cold dry air from the troposphere and deposits it over land masses around 30 degrees latitude is supposed to grow. Studies have shown that it is now depositing drier air around 31.5 degrees latitude and models show it will be increasing.

  8. They will attribute any change to global warming. That is why they changed the name to climate change. They are actually very clever in switching the name as soon as it became obvious that temperatures were not climbing like they predicted.

  9. So the IPCC was originally called the Intergovernmental Panel on Global Warming when it was first established back in 1988?