[ncl-talk] Fwd: Large differences in RH after using mixhum_ptrh and relhum

[yang yang]

Dear Sir/Madam:


I have a few data of air T, P, and RH. I used mixhum_ptrh and relhum to
recalculate RH again. Both the RH should be the same, however, large
differences were found.

Can you please tell me what is the reason? Thanks!

Regards
ED

The codes are:

;*******************************************
begin
;*******************************************
p = (/25132.156,27032.215,33876.102,39419.887/)  ;Pa
t = (/229.690,228.809,225.332,231.278/)         ;K
rh = (/2.008,1.884,62.117,103.124/)              ;%
q = mixhum_ptrh (todouble(p/100.), todouble(t), todouble(rh), 1)
rh1 = relhum (todouble(t),todouble(q),todouble(p))
print(rh1)
print(rh)
end

After run the codes:

 Copyright (C) 1995-2011 - All Rights Reserved
 University Corporation for Atmospheric Research
 NCAR Command Language Version 6.0.0
 The use of this software is governed by a License Agreement.
 See http://www.ncl.ucar.edu/ for more details.

Variable: rh1
Type: double
Total Size: 32 bytes
            4 values
Number of Dimensions: 1
Dimensions and sizes:   [4]
Coordinates:
(0)     2.960429399791643
(1)     2.796223142965527
(2)     94.57799164378163
(3)     150.3954363205561

Variable: rh
Type: float
Total Size: 16 bytes
            4 values
Number of Dimensions: 1
Dimensions and sizes:   [4]
Coordinates:
(0)     2.008
(1)     1.884
(2)     62.117
(3)     103.124
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