Meteo Observations at IGMK

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mfrsr [2020/08/30 19:53] – [Measurement examples] bpospichmfrsr [2021/03/01 11:16] (current) – [Link to current observations] bpospich
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 ===== Principle ===== ===== Principle =====
  
-The **Micro Rain Radar (MRR)** is a vertical pointing FM-CW (frequency modulated –continuous wave) Doppler radar operating at 24.1 GHz (K-band, 12.4 mm wavelength). The emitted radar signal (only 50 mW transmitting power) is backscattered by falling hydrometeors (rain, graupel, snow). From the Doppler spectra the radar reflectivity factor (Ze) and the terminal fall velocity distribution can be derived. +The **Multifilter Rotating Shadowband Radiometer (MFRSR)** is a passive instrument that measures global and diffuse components of solar irradiance at one broadband channel and at six narrowband channels, i. e. at 415, 500, 615, 673, 870, and 940 nm. Direct irradiance is subsequently calculated from the diffuse and global measured components. Each MFRSR measurement sequence includes measurements at four different shadowband positions: 1) at nadir (home position), 2) at the first side-band position, 3) sun-blocked, 4) at the second side-band position. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. From the MFRSR measurements, the aerosol optical depth at the wavelengths 415, 500, 615, 673 and 870 nm as well as the Angstrom exponent can be derived. For single-layer “horizontally homogeneous” liquid clouds, layer cloud optical depth and effective radius can also be retrieved. 
  
-In case of rain the Doppler spectra can be used to derive vertical profiles of microphysical rain properties like drop size distribution and rain rate.  
  
-The MRR system was also studied for its potential to observe snowfall ([[https://link.springer.com/article/10.1007/s00703-011-0142-z|Kneifel et al., 2011]]). Also, an improved MRR algorithm **IMProToo** most suitable for snowfall observations has been developed at IGMK ([[https://amt.copernicus.org/articles/5/2661/2012/amt-5-2661-2012.html|Maahn and Kollias, 2012]]). It is freely available on [[https://github.com/maahn/IMProToo|Github]]. 
-===== Measurement modes ===== 
- 
-  * Vertically pointing observations with integration times from 10 to 3600 seconds.   
-  * The range resolution can be varied from 10 to 200 m which determines together with the 30 range gates the system's maximum height range of 300 to 6000 m.  
  
  
 ===== JOYCE-CF Standard Operation Procedures ===== ===== JOYCE-CF Standard Operation Procedures =====
  
-  * Temporal resolution 10 seconds +  * Direct, diffuse, and total irradiance in 5 spectral bands 
-  * Vertical resolution 35 meters (max. range = 1085 m)+  * Temporal resolution 15 seconds 
 + 
 + ===== Calibration and data quality control ===== 
 + 
 +  * Absolute calibration
  
-===== Calibrations and data quality assurance procedures ===== 
-  * ImProToo features a noise removal based on recognition of the most significant peak and a dynamic dealiasing routine which allows observations even if the Nyquist velocity range is exceeded.  
  
 ===== Data availability ===== ===== Data availability =====
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 ^ Dataset     ^ Temporal resolution       ^ File size          ^ Filename   ^ Remarks   ^  ^ Dataset     ^ Temporal resolution       ^ File size          ^ Filename   ^ Remarks   ^ 
-| Raw data (ASCII)   | 10 seconds    | 1 file per day (~15 MB)     | //YYYYMMDD_jue_mrr_raw_txt.gz//  | METEK format (zipped)   | +| Radiances   | 15 seconds    | 1 file per day (~1.5 MB)     | //DayYYYYMMDD.txt//  |    |
-| IMProToo (NetCDF)   | 1 minute    | 1 file per day (20-30 MB)     | //YYYYMMDD_jue_mrr_improtoo_0-101.nc.gz//  | [[https://github.com/maahn/IMProToo|IMProToo]] product (zipped) | +
- +
-Both available datasets include Doppler spectra, drop spectra, radar reflectivity, rain rate, and fall velocity.+
  
  
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 ===== Link to current observations ===== ===== Link to current observations =====
  
-Data quicklooks can be found in the [[http://gop.meteo.uni-koeln.de/~Hatpro/dataBrowser/dataBrowser3.html?site=JOYCE&date=-1&UpperLeft=MRR_IMProToo&UpperRight=MRR_AveData&LowerRight=Parsivel-Pluvio-MRR_precipitation-rate|JOYCE quicklook browser]].+Data quicklooks can be found in the [[http://atmos.meteo.uni-koeln.de/~hatpro/dataBrowser/dataBrowser2.html?site=JOYCE&date=-1&UpperLeft=MFRSR_Narrowband&UpperRight=MFRSR_Broadband|JOYCE quicklook browser]].
  
 ===== Measurement examples ===== ===== Measurement examples =====
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 | Weight | 4.55 kg | | Weight | 4.55 kg |
 | Power Consumption | 110/220 VAC, 50/60 Hz (50 watts maximum) | | Power Consumption | 110/220 VAC, 50/60 Hz (50 watts maximum) |
-| Manufacturer | [[http://www.yesinc.com/|YES Inc.]]+| Manufacturer | [[http://www.yesinc.com/|YES Inc.]]  |
  
mfrsr.1598810012.txt.gz · Last modified: 2020/08/30 19:53 by bpospich