Search found 619 matches

by ariel.stein
September 6th, 2018, 3:16 pm
Forum: Developers
Topic: Uncertainty along trajectory endpoint
Replies: 3
Views: 444

Re: Uncertainty along trajectory endpoint

This "noise" function or dispersion/turbulent component is a function of time and ws stdev. The uncertainty, as you mentioned in your comment, increases as you go further back in time. In principle, the concentration mode is just a group of trajectories that have a turbulent component included in th...
by ariel.stein
September 6th, 2018, 2:52 pm
Forum: Users
Topic: Problem downloading meteorology data
Replies: 1
Views: 240

Re: Problem downloading meteorology data

How are you downloading the data? through a web browser?
by ariel.stein
August 31st, 2018, 1:27 pm
Forum: Developers
Topic: Uncertainty along trajectory endpoint
Replies: 3
Views: 444

Re: Uncertainty along trajectory endpoint

Conceptually it makes sense. However, your 2-D Gaussian noise should reflect the state of the atmosphere. Ideally, you should use the standard deviation of the horizontal wind speed as a measure for the with of your Gaussian distribution. HYSPLIT explicitly calculates the standard deviations in the ...
by ariel.stein
August 28th, 2018, 12:10 pm
Forum: Users
Topic: Problems with ERAInterim data
Replies: 1
Views: 299

Re: Problems with ERAInterim data

Please make sure you have all the required meteorological variables in the ARL meteorological file that you created. Use the utility program such as chk_file located in the exec directory to see if the variables exist.
by ariel.stein
July 30th, 2018, 4:36 pm
Forum: HYSPLIT for Mac OS X
Topic: ascii2shp conversion software for Mac?
Replies: 1
Views: 681

Re: ascii2shp conversion software for Mac?

Here is the program. Please delete the .txt extension.
by ariel.stein
July 30th, 2018, 4:31 pm
Forum: Dispersion Model
Topic: Changing random number generator seed
Replies: 2
Views: 549

Re: Changing random number generator seed

Unfortunately, the random number generator seed cannot be changed without recompiling the code.
by ariel.stein
May 16th, 2018, 3:34 am
Forum: Trajectory Model
Topic: Trajectory height does not ascend
Replies: 3
Views: 760

Re: Trajectory height does not ascend

The problem you are having is that your trajectories are hitting the ground.
Please take a look at the discussion about the that topic:
viewtopic.php?f=27&t=295&hilit=trajectory+hits+ground
by ariel.stein
May 9th, 2018, 10:17 am
Forum: General questions on meteorological data needed for HYSPLIT
Topic: USER ENTERED UPPER AIR DATA NO WORKING
Replies: 1
Views: 841

Re: USER ENTERED UPPER AIR DATA NO WORKING

Here you can find some information about the user entered meteorological data:
https://www.ready.noaa.gov/documents/Tu ... enter.html
by ariel.stein
May 8th, 2018, 1:18 pm
Forum: Dispersion Model
Topic: HYSPLIT error
Replies: 18
Views: 2187

Re: HYSPLIT error

Try replacing all the 0024 entries by 0001 and the 2400 by 0100. I assume you want to change your emissions hourly.
by ariel.stein
May 4th, 2018, 11:15 am
Forum: Trajectory Model
Topic: Equator
Replies: 1
Views: 678

Re: Equator

That will depend on the underlying meteorology. Evidently in your case there is a fair amount of vertical sheer at that location in the equator. HYSPLIT will only reflect what the meteorological data shows.