[RegCNET] Vertical profile of parameters in RegCM3 output

[Dilip Ganguly]

Hi,

I need help regarding the interpretation of vertical profile of any 
parameter in RegCM output. RegCM output provides values of various 
parameters as a function of sigma pressure levels. So, my question is, how 
to get the values of any parameter as a function of altitude from the 
surface.

When I did sigma to pressure level conversion using the routine SIGMAtoP.f 
for an atmosphere file in the RegCM output, I am getting a parameter 'h' 
(p-level height) in the output file. I wanted to know whether 'h' 
represents the height of vertical levels in sigma coordinate system or 
pressure coordinate system. I have run the model over a domain and I am 
getting the following values of h over a particular grid point in that 
domain.
 
-72.9515 12.3138 141.57 360.507 674.409 1092.6 1629.3 -118524 4107.36 
5180.75 6394.32 7796.92 9453.17 11332.8 13355.6 15561.1 18488.3 inf

I am not able to understand why some of the 'h' values are negative, eg. 
the first one and also another one with value -118524. What is the 
interpretation of negative values of h over any grid point and what about 
the significance of other parameters at those negative heights.

I shall be thankful if someone can explain me these things and help 
me in getting the altitude levels of various parameters in RegCM output.

Thanks in advance,

Dilip. 
  
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Dr. Dilip Ganguly                               
Space And Atmospheric Sciences Division      
Physical Research Laboratory                
Ahmedabad 380009
Gujarat, India
Phone: +91 79 26314558    
Fax:   +91 79 26314659
Alternate Email: ganguly.dilip at gmail.com          
URL: http://www.prl.res.in/~dganguly
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