# Accumulated tendency in version 4.4

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#### cyh082

##### New member
Hi Ming,

I just compiled WRF version 4.4 and tested a new capability of "accumulated physics tendency".

I think I worked! Thanks!

I have two questions.

1) Now, accumulated physics tendency variable has unit of K.
If I set output interval of one hour, then does accumulated tendency mean "accumulated for one hour"?

2) There are a total of 6 variables for theta.
Isn't there accumulated tendency from horizontal/vertical advection?

Thank you for your kind help.

Yonghan

Hi Yonghan,
1) Now, accumulated physics tendency variable has unit of K.
If I set output interval of one hour, then does accumulated tendency mean "accumulated for one hour"?

You are right. The accumulated tendency is over the history output time interval.

2) There are a total of 6 variables for theta.
Isn't there accumulated tendency from horizontal/vertical advection?

No. We didn't separate horizontal from vertical advection.

Hi Ming,

I have an additional question. Could you answer the following question?

There are a total of six "accumulated theta tendency" variables: ATHMPTEN, ATHCUTEN, ATHSHTEN, ATHBLTEN, ATHRATENLW, ATHRATENSW (version 4.4).
And correspondingly, six "theta tendency" variables: H_DIABATIC, RTHCUTEN, RTHSHTEN, RTHBLTEN, RTHRATLW, RTHRATSW (prior to version 4.4).

There is also a variable, RTHFTEN, which denotes total advective potential temperature tendency.
I think that the above variable represents theta tendency from a sum of horizontal and vertical advections.

My question is that
how can I output a variable, which is accumulated version of "RTHFTEN"?

Thanks!

Yonghan

Yonghan,

RTHFTEN is the total advective temperature tendency, including both horizontal and vertical advection terms.it only gets set with a few cumulus schemes, Grell and the new Tiedtke, I think.
You can copy it from the a term in the dynamics called t_tend. This is mu times the advection tendency. Please see related codes in in module_em.F

We didn't output the accumulation of this term because it is small compared to other terms. If you need this term, please manage to get it following the same approach used for other terms.

Hi Ming,

Thank you so much for your kind answers!

Yonghan