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Life hectic at #agu11 ? Tell yourself that when all is calm a diapychal of an isopycnal surface points straight up.

Scientifically an exciting afternoon for me but nothing concrete to report. I had some great conversations and discussions including a detailed tour of Karen Rosenlof’s ozone poster which was in a sense, about teleconnections. Teleconnections in atmospheric science concerns how changes at one height and location in the atmosphere can have significant affects on other atmospheric regions (in this case water vapor variations in the tropics affecting Arctic ozone via modification of large scale planetary (Rossby) waves). Way cool.

Michael McIntyre lecture on the DIapychal Mixing by Baroclinic Overturning (DIMBO)

I’m no oceanographer but that was OK because Michael eased us into in by using the more familiar (to me) atmospheric example of jets. The talk was broken down into


  1. tropospheric jets

  2. striations (ghost jets)

  3. Jovian jets (straight)

  4. Tokamak jets (apparently a similar phenomena occurs in these devices)


  1. vortex dynamics is in balance

  2. PV invertibility: when PV has a step-like change a jet must form

Anatomy: 2 extremes

  1. strong jets: Rossby waves well guided like in the stratosphere

  2. weak jets: PV close to background beta and Rossby waves are unguided

The Physics

  1. strong jets cause eddy-jet barriers. Example: the polar vortex in the stratosphere, which “traps” air inside it and can be associated with regions of significant ozone loss if the air is cold enough and the vortex stable enough (e.g. the Antarctic Ozone Hole).

  2. PV mixing on the equatorward side sharpens the jets

Michael showed several neat videos of these phenomena.

If you want reprints, preprints, this talk etc you can grab it off Michael’s website, google “lucidity principles” and it should be the first hit.

Haven’t spend much time at MW, I’m a South-side g I guess, so I have noticed I think for the first time that on the 3rd floor there is a large terrace you can walk out on and I just ran out and had a look and it is neat, check it out if like me you have been oblivious to it. BTW the Moon is full and I’m going out to howl at it.

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