HMI Science Nugget #4 "New Challenge to Solar Meridional Circulation Theories"

New HMI Science Nuggets are available at http://hmi.stanford.edu/hminuggets, featuring the following topic

#4 "SDO/HMI Observations Create New Challenge to Solar Meridional Circulation Theories" contributed by Mausumi Dikpati

Solar meridional circulation, if mechanically driven and thermally braked, contains two cells in latitude; generating two cells in depth, recently observed by SDO/HMI, is a new challenge to theory.

We invite those who use HMI data for their research, or whose research is closely related to HMI science objectives, to contribute to the HMI science nuggets. -- SDO/HMI team