Question regarding ATCF with Vortex Following

[ray96yelei]

Thank you for your reply. Could you please give me some detailed information about ATCF data after typing grep rsl.out.0000 with vortex_following?
there are several columns data including time，latitude，longitude，slp and vmax? and what is about the last column? is it max wind speed? what is its unit, m/s or n mile/h？what does it represent wind speed, 10 min averaged? can you tell me more detail so that i can compare it with the observation? or can you tell me where to get some information about ATCF? Thank you.

 

[kwerner]

Hi,
I've moved this question to a new post in this section (Special Running Options) because it's a different question than your original, and it's on the specific topic of Vortex Following, which is a special option.

Yes, the final value is the max wind speed, and I believe it's in m/s. You can see if that makes sense, based on the values.

 

[Ming Chen]

Please send me a sample ATCF from your simulations to take a look. Thanks.

 

[ray96yelei]

Hello professor,
Thank you for your reply. I use WRF V4.0 with vortex-following option, the ATCF information is as follows in picture.
through comparing the ATCF information with the best track data, and my question is that:
the max wind speed value in the ATCF is instantaneous value, but the max wind speed value in the best track data is 1 or 2 minutes averaged value or max sustained wind speed value, they cannot be directly compared together. What should I do if I want to compare simualtion max wind speed with the best track? What should I use with max sustained wind speed? Thank you.

 

[Ming Chen]

You should attach a full ATCF file. The information in the picture is not clear and not complete. Anyway please see the answers below to your question:
(1) the maximum wind in ATCF is instantaneous value, and can only be roughly compared with the best track data.
(2) the unit of the max wind speed is knot
(3) common section and fields 1-35 in ATCF are as follows:
BASIN,CY,YYYYMMDDHH,TECHNUM/MIN,TECH,TAU,LatN/S,LonE/W,VMAX,MSLP,TY,RAD,WINDCODE,RAD1,RAD2,RAD3,RAD4,RADP,RRP,MRD,GUSTS,EYE,SUBREGION,MAXSEAS,INITIALS,DIR,SPEED,STORMNAME,DEPTH,SEAS,SEASCODE,SEAS1,SEAS2,SEAS3,SEAS4,USERDEFINED,userdata
several important variables are:
TAU - forecast period: -24 through 240 hours, 0 for best-track, negative taus used for CARQ and WRNG records.
LatN/S - Latitude (tenths of degrees) for the DTG: 0 through 900, N/S is the hemispheric index.
LonE/W - Longitude (tenths of degrees) for the DTG: 0 through 1800, E/W is the hemispheric index.
VMAX - Maximum sustained wind speed in knots: 0 through 300.
MSLP - Minimum sea level pressure, 1 through 1100 MB.
TY - Level of tc development

 

[ray96yelei]

Thank you for your reply. Here is my atcf file with rsl.out.0000，but i find it only five fields there.

 

[Ming Chen]

The five columns in the ATCF correspond to the following variables:
Time, Xlat, Xlong, Minimum Sea level pressure (hpa), Maximum wind speed (in knot)

 

[ray96yelei]

Thank you for your reply. And I have another question that in the wrfout file, there are no turbulent exchange coefficient or boundary layer tuburlent flux. Could you please tell me how to output them in the wrfout file? Thank you.

 

[Ming Chen]

What PBL scheme did you use?

 

[ray96yelei]

Thank you for your reply. And I use some different PBL schemes for sensitivity experiment with WRF V4.0 , including YSU, MYJ, QNSE, MYNN2.5, MYNN3, ACM2, BouLac, BP/UW, TEMF, ShinHong, GBM, MRF, and so on. And reference with the WRF USER GUIDE, maybe not all PBL scheme output exch_m and exch-h, such as ACM2, TEMF, MRF. Could you please tell me how to output turbulent exchange coefficient and boundary layer flux for different PBL schemes in the wrfout file. Thank you.
Besides, I find there is no exch_h or exch_m or turbulent flux variables in Registry.EM file.
Could you please give me some clue or help for that? What should I modify and how to do that? Thanks.

 

[Ming Chen]

You asked such a big question that involves all the PBl schemes. I have to say that you need to do the homework yourself to figure out those variables in each individual PBL scheme. We have no sufficient time and human power to look at all the schemes to find the solution for you. Below is the key issues you need to know:
exch_h and exch_m are exchange coefficients for scalar and momentum variables for all the PBL schemes they apply. For ACM PBL, the coefficients are EDDYZ and EDDYZM, corresponding to eddy diffusivity for heat and momentum. The ACM PBL scheme is different to other PBL schemes in that its vertical mixing calculated from EDDYZM diffusivity only accounts for partial vertical mixing.

 

[ray96yelei]

Thank you so much for your reply. And I have another question.
(1) I find these two lines in Registry.EM_COMMON, and They are exchange coefficients for scalar and momentum variables in ALL the PBL schemes.
state real EXCH_H ikj misc 1 Z r "EXCH_H" "SCALAR EXCHANGE COEFFICIENTS " "m2 s-1"
state real EXCH_M ikj misc 1 Z r "EXCH_M" "EXCHANGE COEFFICIENTS " "m2 s-1"
but the annotation line above these line show is that # MYJ PBL variables; GBM PBL: EXCH_H, EXCH_M.
so are these exchange coefficient for all the PBL scheme or only for MYJ PBL？
(2) in the wrfout file, I konw that HFX is for surface sensible heat flux, LH is for surface latent heat flux and QFX is for surface vapor flux. What is for surface momentum flux? How could I output it?
What are for boundary layer flux, including sensible heat flux, latent heat flux and momentum flux? What should I do to output them?
I cannot find them in the Registry.EM_COMMON.
is there same boundary turbulent flux variables for all the PBL schemes they apply like ccoefficient exch_h and exch_m?
Thank you.