
Level 2a Cloudnet product:Stratocumulus drizzle (radar/lidar method)Data Home  Overview of Cloudnet products  Product list  Quicklooks  Conditions of useSummary
Dataset contentsSample NetCDF file: 20030701_chilbolton_drizzle.nc The following is a description of the variables in this product, produced automatically from the metadata in the sample file (using the nc2html unix utility): Dataset title: Drizzle parameters from Chilbolton
Software version:1.2 Dimensions and coordinate variablestimeTime UTC
Type:singleprecision floatingpoint vector Height above mean sea level
Type:singleprecision floatingpoint vector VariableslatitudeLatitude of site
Type:singleprecision floatingpoint scalar Longitude of site
Type:singleprecision floatingpoint scalar Height of radar above mean sea level
Type:singleprecision floatingpoint scalar Radar frequency
Type:singleprecision floatingpoint scalar Drizzle median diameter This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:mType:singleprecision floatingpoint array Variable containing the random error in Do:Do_error Variable containing the bias in Do:Do_bias Drizzle number concentration This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:m^{4}Type:singleprecision floatingpoint array Variable containing the random error in N:N_error Drizzle DSD shape parameter This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:Type:singleprecision floatingpoint array Variable containing the random error in mu:mu_error Lidar backscattertoextinction ratio, S This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:srType:singleprecision floatingpoint array Variable containing the random error in S:S_error Drizzle liquid water content This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:kg m^{3}Type:singleprecision floatingpoint array Variable containing the random error in lwc:lwc_error Variable containing the bias in lwc:lwc_bias Drizzle liquid water flux This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:kg m^{2}s^{1}Type:singleprecision floatingpoint array Variable containing the random error in lwf:lwf_error Variable containing the bias in lwf:lwf_bias Drizzle terminal fall velocity This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:m s^{1}Type:singleprecision floatingpoint array Variable containing the random error in droplet_fall_velocity:droplet_fall_velocity_error Vertical air velocity This variable was calculated from the 94GHz radar reflectivity factor after correction for gaseous attenuation, the Doppler mean velocity, the Doppler spectral width after correction for turbulence using the 30s standard deviation of the (approximately) 1s mean radar Doppler velocities and the horizontal winds from a forecast model using the technique of Bouniol et al. (2003, Proc. 31st AMS Conf. on Radar Meteorology, Seattle), the lidar backscatter and temperature taken from a forecast model, using the technique of O'Connor et al. (2004) Units:m s^{1}Type:singleprecision floatingpoint array Variable containing the random error in w:w_error Possible bias in drizzle median diameter, one standard deviation This variable is an estimate of the possible systematic error (onestandarddeviation) in drizzle droplet median diameter due to the uncertainty in the calibration of the radar and lidar. Units:dBType:singleprecision floatingpoint scalar Random error in drizzle median diameter, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle droplet median diameter due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Random error in drizzle DSD shape parameter, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle shape parameter due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint scalar Random error in drizzle number concentration, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle number concentration due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Random error in lidar ratio, S, one standard deviation This variable is an estimate of the onestandarddeviation random error in the lidar ratio due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array This variable provides the attenuation correction applied to the lidar backscatter values calculated using the lidar backscattertoextinction ratio, S. Type:singleprecision floatingpoint arrayRandom error in drizzle liquid water content, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle liquid water content due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Random error in drizzle liquid water flux, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle liquid water flux due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Random error in drizzle terminal fall velocity, one standard deviation This variable is an estimate of the onestandarddeviation random error in drizzle terminal fall velocity due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Random error in vertical air velocity, one standard deviation This variable is an estimate of the onestandarddeviation random error in vertical air velocity due to the uncertainty of the retrieval, including the random error in the radar and lidar parameters. Units:dBType:singleprecision floatingpoint array Rain rate Converted to rainrate from raingauge c drop counts Original comment: Converted to rainrate from raingauge c drop counts Units:mm h^{1}Type:singleprecision floatingpoint vector Drizzle parameter retrieval status
This variable describes whether a retrieval was performed for each pixel, and its associated quality, in the form of 6 different classes. The classes are defined in the definition and long_definition attributes. The retrieval method is only performed for precipitation below cloud base and is not possible incloud due to the severe attenuation of the lidar signal. The most reliable retrieval is for precipitation arising from the warm rain process (drizzle), indicated by the value 1, but can also be performed for light precipitation that may have originated from ice clouds, diagnosed by the presence of a melting layer and indicated by the value 2. The retrieval method is not applicable for precipitation within cloud, indicated by the value 3, while a value 4 indicates the presence of liquid water cloud with no precipitation. No attempt is made to retrieve drizzle parameters when rain reaches the ground; this is indicated by the value 5. Type:byte arrayDefinition: These pages are maintained by . 