This data set contains level1 (brightness temperatures) and level2 (retrieved meteorological variables) of the four ground-based microwave radiometers (MWR) measuring during FESSTVaL 2021 (May-August) at Lindenberg (2 MWR, dwd and uzk), Falkenberg (1 MWR, uzk) and Birkholz (1 MWR, uhh).

For each MWR you find up to seven data file types.

Up to two level1 data file types: arbritrary viewing direction (e.g. *mwr00_l1_tb_*) and boundary layer scans (e.g. *mwrBL00_l1_tb_*)
Up to five level2 data file types: path integrated liquid water path (e.g. *_mwr00_l2_clwvi_*),  path integrated water vapor (e.g. *_mwr00_l2_prw_*), coarse vertical resolution water vapor profiles (e.g. *_mwr00_l2_hua_*), coarse vertical resolution temperature profiles (*_mwr00_l2_ta_*), ABL temperature profiles (e.g. *_mwrBL00_l2_ta_*)

mwr00 (mwr01) file types are on a typical temporal resolution of 1-2 seconds, whereas mwrBL00 (mwrBL01) are on a temporal resolution on the order of minutes (3-15), depending on the instrument.

The level2 data sets have been derived by means of multi-variate regression. They rely on long-term radiosonde data sets for training. Note, that ocasionally liquid water path values can be slightly negative due to statistical error.

Please reach out Ulrich Löhnert the contact person in case you detect inconsistencies in the data.

Quality:

All data files are provided with quality flags that are described in the netcdf file headers. Exclude flagged data from automatic analyses, for case studies, use flagged data with care and contact the responsible person named in the file header in case of any doubt.

Integrated liquid water and water vapor from ground-based MWR are amongst the most accurate methods available. Temperature and humidity profiles are only coarsly resolved in the vertical, are, however, continuously available. Temperature vertical resolution decrease quickly with height from tens of meters close to the surface to hundreds of meters at the top of the ABL.  Use mwrBL00_l2_ta profiles for the most accurate temperature profile in the ABL. Humidity profiles contain only roughly two independent pieces of information throughout the whole troposhere.

All level2 data products are delivered with an uncertainty specification.

Project: FESSTVaL (Field Experiment on submesoscale spatio-temporal variability in Lindenberg), a measurement campaign initiated by the Hans-Ertel-Center for Weather Research.

{"references": ["L\u00f6hnert, U., and S. Crewell, 2003: Accuraccy of cloud liquid water path from ground-based microwave radiometry. Part I. Dependency on Cloud model statistics. Radio Science, 38(3), 8041, 2003, doi:10.1029/2002RS002654.", "Crewell, S., and U. L\u00f6hnert, 2003: Accuraccy of cloud liquid water path from ground-based microwave radiometry. Part II. Sensor accuracy and synergy. Radio Science, 38(3), 8042, 2003, doi:10.1029/2002RS002634.", "Crewell, S., and U. L\u00f6hnert, 2007: Accuracy of boundary layer temperature profiles retrieved with multi-frequency, multi-angle microwave radiometry. IEEE Transactions on Geoscience and Remote Sensing, 45(7), 2195-2201, doi:10.1109/TGRS.2006.888434.", "L\u00f6hnert, U. and Maier, O.: Operational profiling of temperature using ground-based microwave radiometry at Payerne: prospects and challenges, Atmos. Meas. Tech., 5, 1121-1134, doi:10.5194/amt-5-1121-2012.", "Steinke, S., S. Eikenberg, U. L\u00f6hnert, G. Dick, D. Klocke, P. Di Girolamo, and S. Crewell, 2015: Assessment of Small-Scale Integrated Water Vapour Variability During HOPE, Atmospheric Chemistry and Physics, Atmos. Chem. Phys., 15, 2675-2692, doi:10.5194/acp-15-2675-2015."]}