William M Briggs: "What is – and what isn't – evidence of global warming"

Statistician to the stars

A very worthwhile read, cutting through the hyperbole of global warming reporting:

Remember when we heard that the icebergs were melting, that polar bears were decreasing in number, that some places were drier than usual and that others were wetter, that the ocean was growing saltier here and fresher there, and that hurricanes were becoming more terrifying? Remember the hundreds of reports on what happens when it gets hot outside?

All of those observations might have been true, but absolutely none of them were evidence of AGW.

Diminishing glaciers did not prove AGW; they were instead a verification that ice melts when it gets hot. Fewer polar bears did not count in favor of AGW; it instead perhaps meant that maybe adult bears prefer a chill to get in the mood. People sidling up to microphones and trumpeting “It’s bad out there, worse than we thought!” was not evidence of AGW; it was evidence of how easily certain people could work themselves into a lather.

No observation of what happened to any particular thing when the air was warm was direct evidence of AGW. None of it.

Every breathless report you heard did nothing more than state the obvious: Some creatures and some geophysical processes act or behave differently when it is hot than when it is cold. Only this, and nothing more.

Read it here.