May 18, 2022 Dataset Open Access

Thermodynamic retrieved profiles from the ASSIST infrared spectrometer, FESSTVaL campaign

Turner, Dave; Rochette, Luc

This dataset contains thermodynamic profiles retrieved from the ground-based infrared spectrometer called the ASSIST.  The ASSIST was located at the "MOLRAO" location at the DWD's Lindenberg site.  The primary retrieved variables are T(z), q(z), liquid water path, and effective radius.  The uncertainties of these variables are provided, as well as a full error covariance matrix.  Most of the information from the ASSIST observation is in the lowest 2 km; the "cumulative degrees of freedom" fields (cdfs_temperature and cdfs_watervapor) provide a quantitative description of this information with height.  The data structure follows the standard DOE Atmospheric Radiation Measurement (ARM) program's data format.  To get the time for the samples, add "base_time" to "time_offset" to get the number of seconds since 1 Jan 1970 at 00:00:00 UTC.

Quality: There are uncertainty profiles for all of the retrieved variables in the netCDF files.  However, the information content in the ASSIST observations decreases rapidly with height; profile quantifies above 3 km should be used with care.  Also, if the retrieved LWP > 10 g/m2, then there will be very little-to-no information on the temperature and humidity profile above the cloud base height.  I also recommend only using retrievals wherein the RMSr field is less than 8 and gamma field is less than 5. All of these variables are in the netCDF file.

Parameters: temperature, waterVapor, LWP, ReffL

Funding: LRtech provided the instrument to FESSTVaL free of charge.  The retrievals were performed under the auspices of the NOAA Atmospheric Science for Renewable Energy program