No one has doubted that there is heating at great heights. Question is where the bulk of the nanoflares occur. As you know I think there are good reasons (the bulk of magnetic field does not rise high into the corona, except perhaps in coronal holes) to believe they occur in the vicinity of the transition region (including the upper chromosphere).
V.

On Jul 31, 2012, at 17:14 , Klimchuk, James A. (GSFC-6710) wrote:


Last point: why can't type-Ii spicules be the manifestation of nanoflares in a stratified inhomogeneous plasma?
 
Depends on where the nanoflares occur.  Nanoflares that occur in the transition region or corona (in plasma that is originally hotter than 10^4 K) will not produce ejections of cold material.  I have a discussion of this in the paper.  Nanoflares that occur deep in the chromosphere, below the eventual spicule, can produce cold ejections.
 

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Viggo H. Hansteen                                   http://www.astro.uio.no/~viggoh
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