Obvious really!

"How do those subtropical anticyclones start?"
I'm sure this is a question that has vexed many of us of a Sunday afternoon.

Well help is at hand from the clever chaps at the Climate Diagnostics Center in Boulder Colorado. They used a linear quasigeostrophic model to show, as we all suspected, that they can be interpreted as a remote response of Rossby waves forced by the large scale heat sources over Asia. I pulled a couple of salient linear equation points and reworked them at home this evening for the kids.

As luck would have it, and not at all contrived like my usual WBC entries, this one fits in quite well with the theme of Linear this week, so will be my entry.

To give the guys their due here is the reference.
Ping Chen, Martin P. Hoerling, and Randall M. Dole, July 2001. "The Origin of the Subtropical Anticyclones" Journal of the Atmospheric Sciences