File Descriptions of Model Data

Files within the LASSO-ENA data set consist of model inputs and outputs from the SAM model. A standardized filename convention is used to uniquely identify these files to assist with their retreival and scripting. This section describes that convention and the different available file types.

Filename Convention

The LASSO-ENA filename convention combines details specific to LASSO modeling with ARM’s naming convention. The approach is similar to the filenames used for LASSO-CACTI, with the primary difference being an adaptation to using the SAM model. For example, SAM does not use nested domains like WRF, so domain numbers are replaced by a more descriptive label. LASSO-ENA also uses more physics-based ensemble members than LASSO-CACTI, which is reflected in the more expressive configuration labels.

The filename convention is as follows, with the first line showing the specific portions of the name and the second line showing a specific example:

sssIIII_FFFFFF_YYYYmmddHHEEEEdWWxXXX_aaaaFn.dl.YYYYmmdd.HHMMSS.ext
enalasso_sam3d_20180630merra2d25x100_sbmwrm-aer2-flxsstC1.m1.20180630.174500.nc

Table 8 describes the various pieces of the filename.

Table 8 Information Contained in LASSO-ENA Filenames.

Category

Description

sss

ARM site identifier, “ena” for the ENA atmospheric observatory

IIII

Instrument name, “lasso” for LASSO

FFFFFF

File type, i.e., the file type abbreviations for the various LASSO-ENA data types, e.g., samin, samrest, and sam3d

YYYYmmddHH

Case date, i.e., model start time

EEEE

Ensemble member data source (ERA5 or MERRA-2), scale of the input sampling rectangle (blank or “s5” = 5 degrees, “s1” = 1 degree), and nudging option (blank or “n0” = no nudging, “n1” = nudging up to boundary layer top, “n2” = nudging up to 2 km; e.g., “merra2s1n0”)

dWWxXXX

Domain setting indicating the domain width (WW) and horizontal grid spacing in meters (XXX); if tall is included, e.g, d25x100tall, the domain extends up to 13 km, otherwise, the default domain top is 9 km, e.g., d25x100

aaaa

Configuration label to identify model configuration settings, typically related to the physics

Fn

ARM facility designation, always C1 for LASSO-ENA

dl

Data level, either m0 (raw model data) or m1 (post-processed model data) for LASSO

YYYYmmdd.HHMMSS

Time of data in the file

ext

Filename extension, “nc” for netCDF files and “tar” for a grouping of files held within a tar file

Note that Table 7 lists the available configuration labels. These labels typically follow the format [microphysics]-[aerosol concentration]-[surface flux option]. However, additional details can be added to uniquely identify a particular configuration that could differ in other aspects.

Also, the filename complexity evolved as additional simulations were produced. The initial smulations used forcing data sampled from a 5-degree rectangle centered on ENA and did not use nudging. Later, simulations using a 1-degree sampling region and different nudging options were added. The initial simulations do not include this information in their filenames, so if no s or n is present, then the default values are s5 and n0, respectively. If either of these are non-default for a given simulation, then both are included in the name, e.g., s1n0 or s1n1.

File Types

The LASSO-ENA simulation data is effectively raw model output from the SAM model with the exception of minor post-processing to convert binary output into netCDF format. The different file types are: