Pielke Jnr takes aim at an absurd article in PNAS (the journal that famously published the upside-down Mann paper and Anderegg's blacklist paper too).
Princeton' professor Michael Oppenheimer predicts that climate change will cause between 1.4 and 6.7 million Mexicans to move to the US, a finding that Pielke lucidly describes as "guesswork piled on top of "what ifs" built on a foundation of tenuous assumptions".
Even more damningly, one of Pielke's commenters points out that there are only 6.3m agricultural workers in Mexico. For Oppenheimer to predict that they will all move north seems preposterous.