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unrealistic values of temperature after ./real.exe

kgeorge

New member
Hello,

I was running the the ./real.exe after the metgrid program and was surprised to see the unrealistic range of values in the temperature,
Can any one please help me with this, my output files and input are by the name , " files_kgeo.tar " in the upload.
i have tried many things to fix it, but couldnt find the actual cause of this error, please help, the values of P and T are totally unrealistic.


thanking you in advance,
kgeorge
 

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Last edited:
In wrfinput. "T" is perturbation potential temperature. T+300 will give you the value of potential temperature.
There is no way you can determine whether the value is reasonable or not by only looking at "T".
 
In wrfinput. "T" is perturbation potential temperature. T+300 will give you the value of potential temperature.
There is no way you can determine whether the value is reasonable or not by only looking at "T".
Thank you very much Ming for your reply, may i please request that if T +300 ( if 300 is the base state temp) , then max value in the T in wrfinput which is 187+300 = 487 K is not reasonable even just by logic right? does we have to add this 300 before we run the wrf.exe?
also, may i please request if an reason for the value of P which is of the range -0.04 to 3355.15 is possible? i guess it is Pa values, so we adding a base state pressure of 100000 Pa to get 'P' values ?

I understand that we cannot determine it just by looking at T , but there should be an expected range of values for the T and P right ? Please correct me if im wrong !

(Please note that files of wrfinput and met file are uploaded in the nextcloud as files_kgeo.tar )
I am sorry that i am bit confused, if in any case ,can you please help me to understand this?

thanking you in advance,
kgeorge
 
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T + 300 gives you the potential temperature.
pressure should be calculated by P + PB, and its unit is pa.

You cannot determine whether the meteorological elements are reasonable or not solely base don P and T.
 
Thank you once again, that solves my issues with Pressure P ( the total pressure ),
but still the temperature T is confusing, i checked the wrfout too it is similar to the value i mentioned in the wrfinput, normally, also as per the met file, temperature has to decrease when going up, but in my case i think the first few layers are ok, but as i go higher in the altitude the T is ( for the top 3 layer , which is around 20km above the surface, has a value of 300 +187 = 487K, it is the same in the case of the wrfout as well, could you please comment on this?


In the met file, the temperature TT is correct .but in the wrfinput and wrfout it changes, instead of decreasing, it is increasing all the way up ..
Could you please help me once again , by checking what happened ?
 
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You can find T in wrfout, which is potential temperature perturbation. By (T+300), you will get potential temperature. By definition, potential temperature increases with height.
 
thank you very much for the response, as a last question may i please ask how can we find the actual temperature instead of the potential temperature?
 
This is the formula to calculate potential temperature from pressure and temperature :

Theta = T*(1000/p)**0.286
 
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