What variables are needed to run this program?

[longbiao1993]

I want to use the code to do some research, and need to know 'what variables are needed to run this program from ecmwf?'.
If author can give some input files, and setting files for an example.

[jkeune]

Hi, and sorry for the late response!

You can run FLEXPART with any forcing (not only ECMWF reanalysis). To be able to run both moisture and heat tracking options with HAMSTER, you need to write the following variables from FLEXPART into the binary partposit* files:

Obligatory variables:

• parcel id
• longitude
• latitude
• height
• specific humidity
• density
• boundary layer height
• temperature

Optional:

• orography (not used in v1.2.0)
• potential vorticity (not used in v1.2.0)
• tropopause height (not used in v1.2.0)

In any case, you need to check if the order of all variables is consistent with the header of main_flex2traj in flex2traj.py.

For an example setup of FLEXPART with a reanalysis from ECMWF (ERA-Interim), see here: https://zenodo.org/records/6947524. This repository contains all namelists and settings that we used to download the forcing with flex_extract v7.0.4 and to run FLEXPART v10.4 with ERA-Interim. More details are listed in the accompanying paper Keune et al., 2022: A unified framework to estimate the origins of atmospheric moisture and heat using Lagrangian models.