Abstract: This data set contains time series of the regional-scale sensible and latent heat fluxes derived from measurements with an optical-microwave scintillometer over a path length of 4.85 km between the Falkenberg boundary layer field site (GM Falkenberg) and the Lindenberg observatory site during the Field Experiment on Sub-mesoscale Spatio-Temporal Variability in Lindenberg (FESSTVaL) from May 18 to August 31, 2021. The Lindenberg Meteorological Observatory – Richard-Aßmann-Observatory and the GM Falkenberg supersites are operated by the German national meteorological service (Deutscher Wetterdienst, DWD). Data are level-2 data as 10-minute averages.

TableOfContents: Surface Upward Sensible Heat Flux; Surface Upward Sensible Heat Flux Quality Flag; Surface Upward Latent Heat Flux; Surface Upward Latent Heat Flux Quality Flag

Technical Info: dimension: 144 x 1; temporalExtent_startDate: 2021-05-01 00:00:00; temporalExtent_endDate: 2021-08-31 23:59:59; temporalResolution: 10; temporalResolutionUnit: minutes; spatialResolution: none; spatialResolutionUnit: none; horizontalResolutionXdirection: none; horizontalResolutionXdirectionUnit: none; horizontalResolutionYdirection: none; horizontalResolutionYdirectionUnit: none; verticalResolution: none; verticalResolutionUnit: meters; horizontalStart: 0; horizontalStartUnit: meters; horizontalEnd: 0; horizontalEndUnit: meters; instrumentNames: BLS-900 optical large aperture scintillometer, MWSC-160 microwave scintillometer; instrumentType: Scintillometer; instrumentLocation: Grenzschichtmessfeld Falkenberg, Lindenberg; instrumentProvider: Scintec AG, Radiometer Physics GmbH

Methods: The fluxes have been derived from simultaneous operation of a BLS-900 large-aperture optical scintillometer and a MWSC-160 microwave scintillometer. Data acquisition, data analysis and flux calculations were performed with the mwsc.exe software package. Structure parameters and the temperature-humidity correlation coefficient (rTq) for each 10min time interval have been calculated twice based on different settings, i.e. using the methods described in Hill (1997, https://doi.org/10.1175/1520-0426(1997)014<0456:AFOASL>2.0.CO;2) which assumes a constant rTq = -0.6 at night and rTq = 0.8 during daytime and in Lüdi et al. (2003, https://doi.org/10.1007/s10546-005-1751-1) which calculates rTq from the cross-correlation of the optical and microwave signals. The similarity model proposed by Koijmans and Hartogensis (2016, https://doi.org/10.1007/s10546-016-0152-y) was then used to derive the heat fluxes from the structure parameters.

Using temperature and humidity profile measurements at the Falkenberg tower and measurements of the radiation budget, the deduced fluxes have been checked for sign consistency with the mean gradients of temperature and humidity and for a violation of the energy budget. In the end “most plausible” fluxes from the two methods (Hill, Lüdi et al. – see above) have been merged to a composite to ensure a better availability / quality of the fluxes especially around sunrise and sunset when the assumptions of the Hill approach typically fail. Quality flags have been assigned to each flux value, where G = good, D = dubious, B = bad, M = missing.

Units: Units for all variables (see TableOfContents): W/m²;1;W/m²;1

geoLocations:

BoundingBox:  westBoundLongitude: 14.1199 degrees East; eastBoundLongitude: 14.1222 degrees East; southBoundLatidude: 52.1665 degrees North; northBoundLatitude: 52.2096 degrees North; geoLocationPlace: Germany, UTM zone 33U
Locations:

    Transmitters: 52.1665 °N, 14.1222 °E, 124 m above mean sea level, 51 m above ground
    Receivers: 52.2096 °N, 14.1199 °E, 129 m above mean sea level, 26 m above ground

Size: Data (level 2 only) are packed into one packed tar-archive. Its size is roughly 400 Kbyte.

Format: netCDF

DataSources: Single site ground-based remote sensing, see "Technical Info" for instruments

Contact: eileen.paeschke (at) dwd.de

Web page: https://www.cen.uni-hamburg.de/en/icdc/data/atmosphere/samd-st-datasets/samd-st-fesstval/sups-rao-oms-l2-turb.html

see also: https://www.cen.uni-hamburg.de/en/icdc/research/samd/observational-data/short-term-observations/fesstval.html

Funding: FESSTVaL is funded by the Deutscher Wetterdienst within the Hans-Ertel Centre for Weather Research.