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Low temperature in coastal areas

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mohouwa

New member
HI~
I am dong a simulation in China from 2017.10.21 to 2017.10.27 , the results show that the average temperature at 2 m near the coastline is seriously underestimated ( picture 1 attched below,the east coast around China and other regions are dramatically decreased ),and it should be around 15 ~ 20 degree C in normal circumstances.
For comparsion , I do the simulation at the same time from 2016.10.21 to 2016.10.27, and the reslult is much more reasonable ( picture 2 attached below ), and I dont know where the problem is , Is it due to the difference in weather conditions?
I use the same namelist.input file in the two simulations except for the simulation year, and my namelist.input is attached below.
Could someone help me to find the reason?
 

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Hi,
Have you taken a look at the raw input data to see what the 2m temps were? If the input data has abnormally low temperatures, or has some "bad" or missing data, that could lead to the difference. I assume you are using the same version of the WRF model, and other than the input dates, nothing is different?
 
kwerner said:
Hi,
Have you taken a look at the raw input data to see what the 2m temps were? If the input data has abnormally low temperatures, or has some "bad" or missing data, that could lead to the difference. I assume you are using the same version of the WRF model, and other than the input dates, nothing is different?

Thanks for your advice! I have checked my met_em* file and the variable T is normal which seems that the input data is not wrong , but when I check the QCLOUD in wrfout_d01* files, it's obviously much higher in the costal areas and be in consistent with T2 (piecture 3 below), The version I used was WRF3.8.1.
However, now I change to WRF4.1.2 with the same namelist settings and the problems seems to be solved,the result of T2 is shown in picture 4 below.
SO is this the result of the difference in the calculation process of physical process in the two versions?
 

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Hi,
Yes, I would think that it has to do with some physics updates that have been made between version 3.8.1 and v4.1.2. I am glad that you were able to resolve the problem. Thank you for letting us know.
 
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