Search found 140 matches

by Fantine
December 17th, 2020, 11:26 am
Forum: Trajectory Model
Topic: Getting Trajectory Data
Replies: 2
Views: 230

Re: Getting Trajectory Data

The trajectory output from HYSPLIT is in ASCII format. Here shows the file format: https://www.ready.noaa.gov/hysplitusersguide/S263.htm
The file name by default is "tdump" or whatever you put in the CONTROL file.
by Fantine
November 25th, 2020, 4:29 pm
Forum: General questions on meteorological data needed for HYSPLIT
Topic: WRF 27km meteorological fields
Replies: 2
Views: 570

Re: WRF 27km meteorological fields

The description of WRF variables used in HYSPLIT is available in https://ready.arl.noaa.gov/data/web/models/hysplit4/decoders/Note-arw2arl.pdf DIFR, DIFT, and DIFW are the difference fields for greater precision for rain, tke, and vertical velocity. Extra variables not listed in the technical note a...
by Fantine
October 2nd, 2020, 3:32 pm
Forum: Trajectory Model
Topic: Trajectory heights from WRF
Replies: 2
Views: 618

Re: Trajectory heights from WRF

HYSPLIT does the interpolation between layers. If you set the starting height of the trajectory at 2 m, HYSPLIT starts the trajectory calculation at 2 m above ground level (terrain height from WRF).
by Fantine
September 21st, 2020, 9:49 am
Forum: Dispersion Model
Topic: Deposition output analysis
Replies: 3
Views: 470

Re: Deposition output analysis

For hourly averaged concentration, you can set the sampling interval to "00 01 00" in the CONTROL file. More detail about setting up the CONTROL for the simulation grid can be found in the user guide: https://ready.arl.noaa.gov/hysplitusersguide/S313.htm (bullet 25 is for sampling interval). In addi...
by Fantine
September 18th, 2020, 9:34 am
Forum: Trajectory Model
Topic: Application Error - Initialization
Replies: 3
Views: 355

Re: Application Error - Initialization

The error message is about the trajecotry start time before the start time of the meteorological data.
Please check the CONTROL file. For computing trajectories for a month, you will need to provide meteorogical data covering the whole month.
by Fantine
September 18th, 2020, 9:27 am
Forum: Dispersion Model
Topic: Deposition output analysis
Replies: 3
Views: 470

Re: Deposition output analysis

HYSPLIT output average concentration. According to your set up, the model writes out 12-hr average concentration.
by Fantine
September 15th, 2020, 4:15 pm
Forum: HYSPLIT Workshop
Topic: Hello,
Replies: 10
Views: 1715

Re: Hello,

The online system is limited for running a large number of trajectories. But it can be done running the model on your own machine. We have a good online tutorial for users desiring to do that: https://www.ready.noaa.gov/documents/Tutorial/html/index.html Here is the instruction for the installation ...
by Fantine
September 15th, 2020, 4:15 pm
Forum: HYSPLIT Workshop
Topic: Hello,
Replies: 10
Views: 312

Re: Hello,

The online system is limited for running a large number of trajectories. But it can be done running the model on your own machine. We have a good online tutorial for users desiring to do that: https://www.ready.noaa.gov/documents/Tutorial/html/index.html Here is the instruction for the installation ...
by Fantine
August 25th, 2020, 4:11 pm
Forum: MeteoInfo Software
Topic: ARL Current & Forecast Meteorology
Replies: 1
Views: 1418

Re: ARL Current & Forecast Meteorology

The utility program in HYSPLIT to compute the Pasquill-Gifford categories is "vmixing.f". It uses diffusivity (m2/s) to obtain the stability classes. The reference paper is Draxler (1979) Atmospheric Environ., Vol 13., pp.1559-1564. Note that HYSPLIT has different options to estimate diffusivity. Th...
by Fantine
August 19th, 2020, 9:22 am
Forum: General questions on meteorological data needed for HYSPLIT
Topic: 2020 NARR data
Replies: 5
Views: 1841

Re: 2020 NARR data

The 27-km WRF archive dataset is now accessible from the web interface. It can be used to run trajectory and dispersion.
For the EDAS40 dataset, we are working on it and plan to resume converting it soon.