Session H10 Solar Cycle

1
Session H10Solar Cycle Dynamo

• Friday, 1030- Noon
• Feb. 17, 2006
• Komm Hoeksema

2
H10 Solar Cycle Dynamo

• Introduction by Rudi outlining purpose
• Rachel on long-term global helioseismology
  results, challenges and opportunities. QA
  Unclear how hard high-l will be. Longer time
  series and increased continuity are the main
  contributions of HMI.

3
H10 Solar Cycle Dynamo

• Tom Duvall on local seismology results,
  challenges and opportunities. Some from Giles
  thesis. Return flow hard put in as continuity
  constraint by Giles. Toms relook still shows
  some anomalies. May be a feature of MDI. This
  topic is something that seems to fall between the
  cracks. Meridional flows are key to progress.

4
H10 Solar Cycle Dynamo

• Mark Miesch about dynamos and how helioseismology
  can help constrain them. He described eight
  specific questions.
• QA How to determine whether helicity is
  conserved? Magnetic data may provide a path to
  answer. Where does dynamo reside? Still not
  certain controversial suggestion that it
  operates throughout CZ. Is there a global scale
  flow associated with tipped bands in Q4 model?
  Yes some, mostly on 2D shells, largely zonal.
  Tom quotes some results suggesting a signal in
  mgt1 (non-zonal) modes. Aimee reports similar in
  sunspot records (with Gilman). What is scale of
  shears and such? Can HS resolve it? E.g.
  downflows are important and more intense in giant
  cells, but small. Larger scale may be more
  possible to see.
• How to get dynamo and HS folks working together?
  No immediate volunteers, but a true working group
  might be useful. Maybe in association with
  another meeting.

5
H10 Solar Cycle Dynamo

• Contributed Sarbani on tachocline temporal and
  spatial dependence. Question about how effects
  at the surface are handled or other systematics
  recognized. Current results are mostly done
  without much accommodation the expectation is
  that to first order they come out in differencing
  during the analysis.
• Contributed Aaron Birch on deep focus
  Time-Distance seismology. Coming back to some
  older work with Tom and Sasha. What is time
  horizon for more progress? Charlie Doug
  working on new spherical code may not solve all
  problems though. Probably long-term project.
• Rachel invite some theorists to next LoHCo
  meeting but Boulder would be good. General
  support. Mark M, Juri, Rudi. Laurent? Theres
  a meeting in Potsdam next April 2007 on dynamos.
  Report some results at LWS-1 next spring. Maybe
  something this fall in Boulder. Organizers will
  propose a date or two.