[RegCNET] divergence

[Michael Notaro]

Does anyone tried using NCL to compute divergence (e.g. 250hPa) from
RegCM4 output?  I tried converting the sigma data to pressure, interpolating the 
data to a regular grid, and then computing divergence, but the result is extremely
noisy even with a monthly average and seems to have computational issues.  
I already emailed ncl-talk with little success.  If there's a recommended method,
let me know.  

Thanks, Michael