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Strange rainc and rainnc

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I am working and using the WRF model for long simulations (10 years) over the tropical area. However, the rainfall quantities from WRF are too small (when I compute precipitation from rainc+rainnc), the large area is 100-300 mm/year) but that is impossible for precipitation in the tropical area.

The WRF outputs were 3 hourly and 8 timesteps in a day.

I also do not have l_rainc and l_rainnc variable in my wrfoutput because I didn't add the bucket scheme in my namelist.output and made my bucket_mm=-1.

how can I solve this problem?

Many thanks,
Can you let us know which version of the model you are using, and attach your namelist.input file so that we can take a look? What input data are you using? Can you also attach a plot or 2 to show your unreasonable results?

I used WRF3.8.1.I attach my example results that are annual precipitation in 2013,2014 and 2015,respective.


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hi kwerner
can I send my namelist.input to you by email? can you give your email address to me?
Thanks for sending that.

One thing that this may be related to is a problem with this version and the tmn_update option with restarts. Take a look at this 'known problems' page that discusses the problem, and how it can be corrected:

I assume that if this is the case, you would also notice a cold bias, which could lead to lower precipitation over time. I'd suggest taking a look at that. Perhaps you could try running a shorter case (a few months) to see if you notice an improvement with the correction. If that doesn't seem to be the problem, then you should look at local soundings to compare, check your SST data to make sure those temps look okay, check your data's surface temperature, 10m temps, moistures, etc. to make sure they all look reasonable.

One more thing to note is that you said that you did not use the bucket_mm option; however, for longer runs like this, we typically recommend using it. Setting it to something like 100 would be a typical monthly value.
Hi kelly

Thanks you so much!
But sorry to ask again.

I already got the results for 10 years periode and I spent 1 year to finished my simulation. Do you have other suggestion to fix my result without re-run again?
This research is my thesis and I don't have much time.