changeset
Move format related files to new dir.
Mon, 06 Feb 2017 14:02:20 +0200
- author
- Iannis <ulalume3@yahoo.com>
- date
- Mon, 06 Feb 2017 14:02:20 +0200
- changeset 99
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- parent 98
- c782e3130fbc
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Move format related files to new dir.
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/docs/file_formats.rst Mon Feb 06 14:02:20 2017 +0200 @@ -0,0 +1,13 @@ +Input/Output file formats +========================= + +In this section of the documentation you can find information about the +input and output files formats of the SCC. + +.. toctree:: + :maxdepth: 2 + + file_formats/netcdf_file + file_formats/low_resolution + +
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/docs/file_formats/low_resolution.rst Mon Feb 06 14:02:20 2017 +0200 @@ -0,0 +1,1519 @@ +Low Resolution SCC L1 Products +============================== + +.. warning:: + This section is still under development. + + +Introduction +------------ + +The Single Calculus Chain (SCC) is the standard EARLINET tool to perform +automatic and quality nchecked analysis of raw lidar data. It is +composed by three different modules: + +- ELPP (EARLINET Lidar Pre-Processor) +- ELDA (EARLINET Lidar Data Analizer) +- ELDEC (EARLINET Lidar DEpolarization Calibrator) + +Whenever an input file containing raw lidar data has been submitted to +the SCC ELPP is automatically ran on it. The ELPP module pre-processes +the raw data performing all the corrections and data handling needed +before the optical retrieval algorithms can be applied by ELDA module. +The ELPP output files contain pre-processed range corrected signals +corrected for instrumental effects as well as atmospheric molecular +parameters calculated from standard model or radiosounding. Typically, +the vertical and temporal resolutions of the pre-processed signals +included in these files is lower than the raw vertical and temporal +resolution as in general time/vertical integration is performed by ELPP +to increase the SNR and allow the calculation of optical products with a +reduced uncertainties. As a consequence the ELPP output files are called +Low Resolution SCC L1 Products. Another SCC module (HiRELPP – High +Resolution EARLINET Lidar Pre-Processor) currently under development +will produce High Resolution SCC L1 Products in which both time and +vertical resolution are kept as higher as possible. + +This document provides a detailed description about the structure and +the format of Low Resolution SCC L1 Product as produced by the SCC v4.0. + +Low Resolution SCC L1 Product: File format +------------------------------------------ + +The Low Resolution SCC L1 Products are files in Network Common Data Form +(NetCDF) which is a well known self-describing, machine-independent data +format that support the creation, access, and sharing of array-oriented +scientific data. For more information about NetCDF format: +http://www.unidata.ucar.edu/software/netcdf/. + +The NetCDF is a binary format that allows the definition of +multi-dimensional variables of several types (integers, double, +character, etc). For each variable it is possible to define one or more +attributes where to specify variable properties like units, long name, +description, etc. + +It is possible to define global attributes which are not related to a +specific variable but to the whole file. + +A NetCDF file is composed by four different section: + +- dimensions + + this section contains all the dimensions used in the definition of + all the variables included in the NetCDF file + +- variables + + this section contains all the variables stored in the NetCDF file. + Each variable is defined as a multi-dimensional array of a specific + type and with all the dimensions defined in the dimensions section + + global attributes + + this section lists all the attributes referring to the whole file. As + the variable the attributes (global or the one attached to a specific + variable) can be of different type + +- data + + in this section the data contained in each variable defined in + variable section is stored. Attribute values (both global or related + to a specific variable) are not reported in data section but directly + in variable or global attribute sections. + +Each Low Resolution SCC L1 Product correspond to a single emission +wavelength. For example it is possible to find in the same file the +elastic and the Raman channel pre-processed time-series corresponding to +the same emission wavelength (but to a different detection wavelengths) +but not two elastic time-series referring to different emission +wavelengths. + +Low Resolution SCC L1 Product Format: dimensions +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The following dimensions are defined in the Low Resolution SCC L1 +Product: + +- time +- points +- channels +- scan\_angles + +The dimension *time* specifies the number of RCS (for each channel) +composing all the pre-processed time-series reported in the file. + +The dimension *points* represents the number of rangebins characterizing +the pre-processed RCS. In case RCSs corresponding to different channels +are characterized by different rangebins the dimension time is to the +the maximum value of rangebins. + +The dimension *channels* indicates the number channels at which the RCS +time-series included in the file refer to. + +The dimension *scan\_angles* takes into account how many zenith scan +angles have been used to measure the RCS time-series reported into the +file + + +Low Resolution SCC L1 Product Format: variables +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In this section all the possible Low Resolution SCC L1 Product variables +are reported. There are some variables that are mandatory and have to be +present in all the Low Resolution SCC L1 Product files while there are +others that have to be present only in specific cases. + +Technical Variables +################### + +altitude\_resolution + :Type: *double* + :Number of dimensions: 1 + :Dimensions: *scan\_angles* + :Location: Included in all the Low Resolution SCC L1 Product files + :NetCDF definition: *double altitude\_resolution(scan\_angles)* + :Description: this variable describes the altitude resolution + corresponding to the RCS time-series reported in the file. It is needed + to compute the vertical scale of the RCS corresponding to each scan + angle which should be calculated as it follow: + + where *z* is the altitude, ** is the scan angle value and *h* is the + value reported by *altitude\_resolution* variable. + +- Variable name: *range\_resolution* + +:Type: *double* +:Number of dimensions: 1 +:Dimensions: *scan\_angles* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double range\_resolution(scan\_angles)* +:Description: this variable describes the range resolution corresponding +to the RCS time-series reported in the file. It is needed to compute the +range scale of the RCS corresponding to each scan angle which should be +calculated as it follow: + +where *r* is the range, ** is the scan angle value and *r* is the +value reported by *range\_resolution* variable. Altitude and range +resolution are the same if the scan angle is zero (zenith acquisition). + +- Variable name: *laser\_pointing\_angle* + +:Type: *double* +:Number of dimensions: 1 +:Dimensions: *scan\_angles* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double laser\_pointing\_angle(scan\_angles)* +:Description: this variable provides the value of the zenith scan angles +used during the measurement. The value of angle are in degrees with +respect to the zenith direction. + +- Variable name: *emission\_wavelength* + +:Type: *double* +:Number of dimensions: 1 +:Dimensions: *channels* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double emission\_wavelength(channels)* +:Description: this variable provides the value of the emission wavelength +(in nm) corresponding to each RCS time-series. + +- Variable name: *detection\_wavelength* + +:Type: *double* +:Number of dimensions: 1 +:Dimensions: *channels* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double detection\_wavelength(channels)* +:Description: this variable provides the value of the detection +wavelength (in nm) corresponding to each RCS time-series. For elastic +channels the detection and emission wavelength are the same or slightly +different. + +- Variable name: *laser\_pointing\_angle\_of\_profiles* + +:Type: *integer* +:Number of dimensions: 1 +:Dimensions: *time* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int laser\_pointing\_angle\_of\_profiles(time)* +:Description: this variable allows to identify the zenith angle at which +each single RCS contained in the time-series refer to. In particular, +for a given time the variable +*laser\_pointing\_angle\_of\_profiles(time)* provides the scan angle +index at which all the RCS included in the file refer to at the same +time. To get the value of the scan angle the variable +*laser\_pointing\_angle* should be evaluated in correspondence of the +index returned by the variable +*laser\_pointing\_angle\_of\_profiles(time)*. + +- Variable name: *shots* + +:Type: *integer* +:Number of dimensions: 1 +:Dimensions: *time* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int shots(time)* +:Description: this variable report the number of laser shots that have +been integrated the all the RCS time-series at a given time. + +- Variable name: *start\_time* + +:Type: *integer* +:Number of dimensions: 1 +:Dimensions: *time* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int start\_time(time)* +:Description: Variable reporting the value of the start time of each RCS +within all the time-series in seconds since the start of measurement. + +- Variable name: *stop\_time* + +:Type: *integer* +:Number of dimensions: 1 +:Dimensions: *time* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int stop\_time(time)* +:Description:Variables reporting the value of the stop time of each RCS +within all the time-series in seconds since the start of the +measurement. + +- Variable name: *LR\_Input* + +:Type: *integer* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present only if the Low Resolution SCC L1 Product corresponds +to an elastic only product +:NetCDF definition: *int LR\_Input* +:Description: this variable is only used by ELDA module in the elastic +only retrieval to know which value of particle lidar ratio assume in the +retrieval. A value of 1 means to use a fixed value stored in the SCC +database for each product. A value of 0 means to use a profile of lidar +ratio provided by the user as external file. + +- Variable name: *overlap\_correction* + +:Type: *integer* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int overlap\_correction* +:Description: this variable provides information on the overlap +correction of all the RCS time-series included in the file. If it is set +to 1 the overlap correction has been applied if it is set to null value +the overlap correction has not been applied. + +- Variable name: *cloud\_flag* + +:Type: *integer* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *int cloud\_flag(time, points)* +:Description: variable reporting the cloud mask on the RCS time-series +included in the file. A value of 1 means no cloud any other values +different from 1 correspond to the presence of cloud. + +Atmospheric Molecular Variables +############################### + +- Variable name: *Elastic\_Mol\_Extinction* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *scan\_angles, points* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double Elastic\_Mol\_Extinction(scan\_angles, +points)* +:Description: this variable provides the value of molecular extinction +coefficient at elastic wavelength in m\ :sup:`-1` at a given scan angle +and altitude (points). The values are calculated from standard models or +from radiosounding (submitted to the SCC as external input files) + +- Variable name: *LR\_Mol* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double LR\_Mol* +:Description: The value of calculated molecular lidar ratio in sr. + +- Variable name: *Emission\_Wave\_Mol\_Trasmissivity* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *scan\_angles, points* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double +Emission\_Wave\_Mol\_Trasmissivity(scan\_angles, points)* +:Description: this variable provides the value of molecular trasmissitivy +at emission wavelength at a given scan angle and altitude (*points*). + +- Variable name: *Detection\_Wave\_Mol\_Trasmissivity* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *scan\_angles, points* +:Location: Included in all the Low Resolution SCC L1 Product files +:NetCDF definition: *double +Detection\_Wave\_Mol\_Trasmissivity(scan\_angles, points)* +:Description: this variable provides the value of molecular trasmissitivy +at detection wavelength at a given scan angle and altitude (*points*). + +Aerosol Related Variables +######################### + +- Variable name: *elT* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves one +single elastic channel not split in near and far range +:NetCDF definition: *double elT(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to an elastic channel. The RCS may correspond to a single +physical lidar channel or to two physical channels (one optimized for +the near range and the other for the far range) that have been glued by +ELPP module. + +- Variable name: *elT\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves one +single elastic channel not split in near and far range +:NetCDF definition: *double elT\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elT*. + +- elTnr +:Variable name: *elTnr* +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a near + range elastic channel +:NetCDF definition: *double elTnr(time, points)* +:Description: this variable contains the time-series of the RCS + corresponding to a near range elastic channel. If this variable is + present also the corresponding *elTfr* variable should be present in + the file. + +- Variable name: *elTnr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a near +range elastic channel +:NetCDF definition: *double elTnr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elTnr*. + +- Variable name: *elTfr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a far +range elastic channel +:NetCDF definition: *double elTfr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to a far range elastic channel. If this variable is +present also the corresponding *elTnr *\ variable should be present in +the file. + +- Variable name: *elTfr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a far +range elastic channel +:NetCDF definition: *double elTfr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elTfr*. + +- Variable name: *vrRN2* + +:Type:\ * double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves one +vibro-rotational N2 Raman channel not split in near and far range +:NetCDF definition: d\ *ouble vrRN2(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to a vibro-rotational N2 Raman channel. The RCS may +correspond to a single physical lidar channel or to two physical +channels (one optimized for the near range and the other for the far +range) that have been glued by ELPP module. + +- Variable name: *vrRN2\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves one +vibro-rotational N2 Raman channel not split in near and far range +:NetCDF definition: *double vrRN2\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *vrRN2*. + +- Variable name: *vrRN2nr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a near +range vibro-rotational N2 Raman channel +:NetCDF definition: *double vrRN2nr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to a near range vibro-rotationl N2 Raman. If this variable +is present also the corresponding *vrRN2fr *\ variable should be present +in the file. + +- Variable name: *vrRN2nr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a near +range vibro-rotational N2 Raman channel +:NetCDF definition: *double vrRN2nr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *vrRN2nr*. + +- Variable name: *vrRN2fr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a far +range vibro-rotational N2 Raman channel +:NetCDF definition: *double vrRN2fr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to a far range vibro-rotationl N2 Raman. If this variable +is present also the corresponding *vrRN2nr *\ variable should be present +in the file. + +- Variable name: *vrRN2fr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves a far +range vibro-rotational N2 Raman channel +:NetCDF definition: *double vrRN2fr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *vrRN2fr*. + +Polarization related variables +############################## + +- Variable name: *elPT* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels not split in near and far range +:NetCDF definition: *double elPT(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the elastic polarization component which is transmitted +by the polarization sensitive optical subsystem. This component may +correspond to a total, cross or parallel polarization component +depending on the particular system configuration. Moreover the RCS may +correspond to a single physical lidar channel or to two physical +channels (one optimized for the near range and the other for the far +range) that have been glued by ELPP module. + +- Variable name: *elPT\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves +spolarization sensitive elastic channels not split in near and far range +:NetCDF definition: *double elPT\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPT*. + +- Variable name: *elPTnr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double elPTnr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the near range elastic polarization component which is +transmitted by the polarization sensitive optical subsystem. This +component may correspond to a total, cross or parallel polarization +component depending on the particular system configuration. If this +variable is present also the corresponding *elPTfr* variable should be +present in the file. + +- Variable name: *elPTnr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double elPTnr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPTnr*. + +- Variable name: *elPTfr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double elTfr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the far range elastic polarization component which is +transmitted by the polarization sensitive optical subsystem. This +component may correspond to a total, cross or parallel polarization +component depending on the particular system configuration. If this +variable is present also the corresponding elPTnr variable should be +present in the file. + +- Variable name: *elPTfr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double elPTfr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPTfr*. + +- Variable name: *elPR* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels not split in near and far range +:NetCDF definition: *double elPR(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the elastic polarization component which is reflected +by the polarization sensitive optical subsystem. This component may +correspond to a total, cross or parallel polarization component +depending on the particular system configuration. Moreover the RCS may +correspond to a single physical lidar channel or to two physical +channels (one optimized for the near range and the other for the far +range) that have been glued by ELPP module. + +- Variable name: *elPR\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels not split in near and far range +:NetCDF definition: *double elPR\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPR*. + +- Variable name: *elPRnr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: * time, points* +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double elPTnr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the near range elastic polarization component which is +reflected by the polarization sensitive optical subsystem. This +component may correspond to a total, cross or parallel polarization +component depending on the particular system configuration. If this +variable is present also the corresponding *elPRfr* variable should be +present in the file. + +- Variable name: *elPRnr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: * double elPRnr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPRnr*. + +- Variable name: *elPRfr* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double elPRfr(time, points)* +:Description: this variable contains the time-series of the RCS +corresponding to the far range elastic polarization component which is +reflected by the polarization sensitive optical subsystem. This +component may correspond to a total, cross or parallel polarization +component depending on the particular system configuration. If this +variable is present also the corresponding *elPRnr* variable should be +present in the file. + +- Variable name: *elPRfr\_err* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *time, points* +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double elPRfr\_err(time, points)* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *elPRfr*. + +- Variable name: *G\_T* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double G\_T* +:Description: G polarization cross-talk factor value corresponding to the +polarization transmitted channel. + +- Variable name: *G\_T\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_T*. + +- Variable name: *G\_T\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_T*. + +- Variable name: *H\_T* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_T* +:Description: H polarization cross-talk factor value corresponding to the +polarization transmitted channel. + +- Variable name: *H\_T\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_T*. + +- Variable name: *H\_T\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_T*. + +- Variable name: *G\_R* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double G\_R* +:Description: G polarization cross-talk factor value corresponding to the +polarization reflected channel. + +- Variable name: *G\_R\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_R*. + +- Variable name: *G\_R\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: * double G\_R\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_R*. + +- Variable name: *H\_R* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_R* +:Description: H polarization cross-talk factor value corresponding to the +polarization reflected channel. + +- Variable name: *H\_R\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_R*. + +- Variable name: *H\_R\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_R*. + +- Variable name: *Polarization\_Channel\_Gain\_Factor* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double Polarization\_Channel\_Gain\_Factor* +:Description: this variable reports the value of the gain ratio of the +reflected and transmitted polarization channels. + +- Variable name: *Polarization\_Channel\_Gain\_Factor\_Statistical\_Err + * + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *Polarization\_Channel\_Gain\_Factor*. + +- Variable name: *Polarization\_Channel\_Gain\_Factor\_Systematic\_Err + * + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *Polarization\_Channel\_Gain\_Factor*. + +- Variable name: *Polarization\_Channel\_Gain\_Factor\_Correction* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Correction* +:Description: this variable reports the value of the correction to the +gain ratio of the reflected and transmitted polarization channels. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: * double +Polarization\_Channel\_Gain\_Factor\_Correction\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Correction\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction*. + +- Variable name: *G\_T\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Near\_Range* +:Description: G polarization cross-talk factor value corresponding to the +near range polarization transmitted channel. + +- Variable name: *G\_T\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Near\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_T\_Near\_Range*. + +- Variable name: *G\_T\_Near\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Near\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_T\_Near\_Range*. + +- Variable name: *H\_T\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Near\_Range* +:Description: H polarization cross-talk factor value corresponding to the +near range polarization transmitted channel. + +- Variable name: *H\_T\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Near\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_T\_Near\_Range*. + +- Variable name: *H\_T\_Near\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Near\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_T\_Near\_Range*. + +- Variable name: *G\_R\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Near\_Range* +:Description: G polarization cross-talk factor value corresponding to the +near range polarization reflected channel. + +- Variable name: *G\_R\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Near\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_R\_Near\_Range*. + +- Variable name: *G\_R\_Near\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Near\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_R\_Near\_Range*. + +- Variable name: *H\_R\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Near\_Range* +:Description: H polarization cross-talk factor value corresponding to the +near range polarization reflected channel. + +- Variable name: *H\_R\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: * double H\_R\_Near\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_R\_Near\_Range*. + +- Variable name: *H\_R\_Near\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Near\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_R\_Near\_Range*. + +- Variable name: *Polarization\_Channel\_Gain\_Factor\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Near\_Range* +:Description: this variable reports the value of the gain ratio of the +near range reflected and transmitted polarization channels. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Near\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Near\_Range\_Factor*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Near\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Near\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Near\_Range*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range* +:Description: this variable reports the value of the correction to the +near range gain ratio of the reflected and transmitted polarization +channels. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition:\ ** + +*double +Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range\_Statistical\_Err +* +:Description: this variable describes the statistical uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range\_Systematic\_Err + * + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves near +range polarization sensitive elastic channels +:NetCDF definition: + + *double +Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range\_Systematic\_Err +* +:Description: this variable describes the systematic uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction\_Near\_Range*. + +- Variable name: *G\_T\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Far\_Range* +:Description: G polarization cross-talk factor value corresponding to the +far range polarization transmitted channel. + +- Variable name: *G\_T\_Far\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Far\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_T\_Far\_Range*. + +- Variable name: *G\_T\_Far\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_T\_Far\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_T\_Far\_Range*. + +- Variable name: *H\_T\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Far\_Range* +:Description: H polarization cross-talk factor value corresponding to the +far range polarization transmitted channel. + +- Variable name: *H\_T\_Far\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double H\_T\_Far\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_T\_Far\_Range*. + +- Variable name: *H\_T\_Far\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: d\ *ouble H\_T\_Far\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_T\_Far\_Range*. + +- Variable name: *G\_R\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Far\_Range* +:Description: G polarization cross-talk factor value corresponding to the +far range polarization reflected channel. + +- Variable name: *G\_R\_Far\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Far\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *G\_R\_Far\_Range*. + +- Variable name: *G\_R\_Far\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double G\_R\_Far\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *G\_R\_Far\_Range*. + +- Variable name: *H\_R\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Far\_Range* +:Description: H polarization cross-talk factor value corresponding to the +far range polarization reflected channel. + +- Variable name: *H\_R\_Far\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Far\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable *H\_R\_Far\_Range*. + +- Variable name: *H\_R\_Far\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double H\_R\_Far\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable *H\_R\_Far\_Range*. + +- Variable name: *Polarization\_Channel\_Gain\_Factor\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Far\_Range* +:Description: this variable reports the value of the gain ratio of the +far range reflected and transmitted polarization channels. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Far\_Range\_Statistical\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Far\_Range\_Statistical\_Err* +:Description: this variable describes the statistical uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Far\_Range\_Factor*. + +- Variable name: + P\ *olarization\_Channel\_Gain\_Factor\_Far\_Range\_Systematic\_Err* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: *double +Polarization\_Channel\_Gain\_Factor\_Far\_Range\_Systematic\_Err* +:Description: this variable describes the systematic uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Far\_Range*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range* + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: d\ *ouble +Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range* +:Description: this variable reports the value of the correction to the +far range gain ratio of the reflected and transmitted polarization +channels. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range\_Statistical\_Err + * + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: + +d\ *ouble +Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range\_Statistical\_Err +* +:Description: this variable describes the statistical uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range*. + +- Variable name: + *Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range\_Systematic\_Err + * + +:Type: *double* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves far +range polarization sensitive elastic channels +:NetCDF definition: + +*double +Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range\_Systematic\_Err +* +:Description: this variable describes the systematic uncertainties +corresponding to the variable +*Polarization\_Channel\_Gain\_Factor\_Correction\_Far\_Range*. + +- Variable name: *Depolarization\_Calibration\_Type* + +:Type: *integer* +:Number of dimensions: 0 +:Dimensions: N/A +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: * int Depolarization\_Calibration\_Type* +:Description: this variable describes the type of depolarization +calibration that has been performed. A value of 1 means automatic +calibration made the the SCC, a value of 2 means manual calibration +inserted into the SCC database. + +- Variable name: *Molecular\_Linear\_Depolarization\_Ratio* + +:Type: *double* +:Number of dimensions: 2 +:Dimensions: *scan\_angles,points* +:Location: Present if the Low Resolution SCC L1 Product involves +polarization sensitive elastic channels +:NetCDF definition: *double +Molecular\_Linear\_Depolarization\_Ratio(scan\_angles, points)* +:Description: this variable report the value of molecular linear +depolarization ration for at given scan angles and at given altitude +(*points*). This profile is calculated on the base of the atmospheric +data from standard models or radiosonding submitted by the user as +separate file. + +The altitude scale at which each RCS within the time-series reported by +the variables *elT, elTnr, elTfr, vrRN2, vrRN2nr, vrRN2fr, elPT, elPTnr, +elPTfr, elPR, elPRnr, elPRfr*, refer to can be obtained as: + +H(laser\_pointing\_angle\_of\_profiles(time),points) + +The total signal (*I*\ :sub:`*total*`) and the volume depolarization +ratio (**) can be calculated out of reflected (*I*\ :sub:`*R*`) and +transmitted (*I*\ :sub:`*T*`) polarization component intensities using +the following equations: + +where *\** is the gain ratio of the reflected and transmitted +polarization channels (variable *Polarization\_Channel\_Gain\_Factor*); +*K* is the correction to the gain ratio of the reflected and transmitted +polarization channels (variable +*Polarization\_Channel\_Gain\_Factor\_Correction*); *I*\ :sub:`*R*` is +the intensity of the reflected polarization component (variable *elPR*); +*I*\ :sub:`*T*` is the intensity of the transmitted polarization +component (variable *elPT*); and *G*\ :sub:`*T*`, *H*\ :sub:`*T*`, +*G*\ :sub:`*R*` and *H*\ :sub:`*R*` are the polarization cross-talk +parameters (variables *G\_T, H\_T, G\_R* and *H\_R*). + +Low Resolution SCC L1 Product Format: global attributes +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +In this section all the possible Low Resolution SCC L1 Product global +attributes are reported. There are some global attributes that are +mandatory and have to be present in all the Low Resolution SCC L1 +Product files while there are others that have to be present only in +specific cases. + +1. Attribute name: *Location* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the name of site where the measurements have been performed + +1. Attribute name: *System* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the name of the lidar system used to perform the +measurements + +1. Attribute name: *Latitude\_degrees\_north* + +:Type: *double* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the latitude (in degrees North) of the measurement site + +1. Attribute name: *Longitude\_degrees\_east* + +:Type: *double* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the longitude (in degrees East) of the measurement site + +1. Attribute name: *Altitude\_meter\_asl* + +:Type: *double* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the altitude (in m above see level) of the measurement site + +1. Attribute name: *Measurement\_ID* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: within the SCC all the measurement sessions is identified +by a string called *Measurement\_ID* uniquely. This gobal attributes +provides this string. + +1. Attribute name: *Measurement\_Start\_Date* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the start date of the measurements. The format in which +this date is written is specified in the gobal attribute +*Measurement\_Date\_Format*. + +1. Attribute name: *Measurement\_Date\_Format* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the format in which the global attribute +*Measurement\_Start\_Date* is given. + +1. Attribute name: *Measurement\_Start\_Time\_UT* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the start time (UT) of the measurements. The format in +which this time is written is specified in the global attribute +*Measurement\_Time\_Format*. + +1. Attribute name: *Measurement\_Time\_Format* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the format in which the global attribute +*Measurement\_Start\_Time\_U*\ T is given. + +1. Attribute name: *Comments* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: this string can contain comments of the measurement session + +1. Attribute name: *Overlap\_File\_Name* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files for +which an overlap file has been submitted by the data originator. +:Description: The name of the overlap file to use for overlap correction. + +1. Attribute name: *LR\_File\_Name* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +corresponding to elastic only retrieval and for which an lidar ratio +profile file has been submitted by the data originator. +:Description: The name of the lidar ratio file containing the profile of +particle lidar ratio values to use as input in the elastic only +retrieval. + +1. Attribute name: *SCCPreprocessingVersion* + +:Type: *string* +:Location: Included in all the Low Resolution SCC L1 Product files +:Description: the version of SCC used to produce the current Low +Resolution SCC L1 Product + +Low Resolution SCC L1 Product Filename +-------------------------------------- + +The filename of the Low Resolution SCC L1 Products has the following +format: + +measurementid\_prodid.nc + +The *measurementid* is a 12 characters alphanumeric string identifying +the measurement session at which the product refers to. The +*measurementid* (which is unique for a given measurement session) allows +to fully trance the SCC analysis performed on the current product. This +can be done because each measurement session is recorded in a SCC +database using the same string. In the same database the measurement +session is linked to the lidar configuration used to analyze the data +(which is recorded and fully characterized in the SCC database providing +all the channel details) and to a set of optical products to calculate. + +The *prodid* is a numeric string identifying the optical product that +has to be calculated by SCC (in particular ELDA module) by applying the +optical retrieval algorithm on the current pre-processed L1 product. + +Different product types are defined within the SCC. The contents of a +Low Resolution SCC L1 product depends on the type of the product +specified in the its filename by prodid string. In particular only the +**Aerosol Related Variables **\ and\ ** Polarization related variables** +specified in the section 2.2 can change depending on product type. In +Tab. 3.1 are reported the product-type related variables for each +optical product type. + +To link the *prodid* string with the corresponding product type the SCC +database a proper query to the SCC database should be addressed. + +**Table 3.1:** Possible variables that can be found in the SCC L1 +Products for each optical product type + ++--------------------------------------------------------------+---------------------------------------------------+ +| Product type | Possible variables in Low Resolution L1 Product | ++--------------------------------------------------------------+---------------------------------------------------+ +| Extinction only | vrRN2, vrRN2nr, vrRN2fr | +| | | +| | vrRN2\_err, vrRN2nr\_err, vrRN2fr\_err | ++--------------------------------------------------------------+---------------------------------------------------+ +| Elastic Backscatter | elT, elTnr, elTfr | +| | | +| Elastic Backscatter + Particle Linear Depolarization Ratio | elT\_err, elTnr\_err, elTfr\_err | +| | | +| | elPR, elPRnr, elPRfr | +| | | +| | elPR\_err, elPRnr\_err, elPRfr\_err | +| | | +| | elPT, elPTnr, elPTfr | +| | | +| | elPT\_err, elPTnr\_err, elPTfr\_err | ++--------------------------------------------------------------+---------------------------------------------------+ +| Raman Backscatter | elT, elTnr, elTfr | +| | | +| Raman Backscatter + Particle Linear Depolarization Ratio | elT\_err, elTnr\_err, elTfr\_err | +| | | +| Lidar Ratio | elPR, elPRnr, elPRfr | +| | | +| | elPR\_err, elPRnr\_err, elPRfr\_err | +| | | +| | elPT, elPTnr, elPTfr | +| | | +| | elPT\_err, elPTnr\_err, elPTfr\_err | +| | | +| | vrRN2, vrRN2nr, vrRN2fr | +| | | +| | vrRN2\_err, vrRN2nr\_err, vrRN2fr\_err | ++--------------------------------------------------------------+---------------------------------------------------+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/docs/file_formats/netcdf_file.rst Mon Feb 06 14:02:20 2017 +0200 @@ -0,0 +1,1250 @@ +.. _netcdf_file: + +The SCC input netCDF file format +================================ + +A more detailed version of this document can be found in this :download:`pdf file <../files/NetCDF_input_file_v3.pdf>`. + +.. note:: + + You can check the format of the files you create using the linked `script <https://bitbucket.org/iannis_b/scc-netcdf-checker>`_ . + + +Rationale +--------- + +The Single Calculus Chain (SCC) is composed by three different modules: + +- pre-processing module (*ELPP*) + +- optical processing module (*ELDA*) + +- depolarization calibrator module (*ELDEC*) + +To perfom aerosol optical retrievals the SCC needs not only the raw +lidar data but also a certain number of parameters to use in both +pre-processing and optical processing stages. The SCC gets these +parameters looking at two different locations: + +- Single Calculus Chain relational database (SCC\_DB) + +- Input files + +There are some paramenters that can be found only in the input files +(those ones changing from measurement to measurement), others that can +be found only in the SCC\_DB and other ones that can be found in both +these locations. In the last case, if a particular parameter is needed, +the SCC will search first in the input files and then in SCC\_DB. If the +parameter is found in the input files, the SCC will keep it without +looking into SCC\_DB. + +The input files have to be submitted to the SCC in NetCDF format. At +present the SCC can handle four different types of input files: + +1. Raw Lidar Data + +2. Sounding Data + +3. Overlap + +4. Lidar Ratio + +As already mentioned, the *Raw lidar data* file contains not only the +raw lidar data but also other parameters to use to perform the +pre-processing and optical processing. The *Sounding Data* file contains +the data coming from a correlative radiosounding and it is used by the +SCC for molecular density calculation. The *Overlap* file contains the +measured overlap function. The *Lidar Ratio* file contains a lidar ratio +profile to use in elastic backscatter retrievals. The *Raw Lidar Data* +file is of course mandatory and the *Sounding Data*, *Overlap* and +*Lidar Ratio* files are optional. If *Sounding Data* file is not +submitted by the user, the molecular density will be calculated by the +SCC using the "US Standard Atmosphere 1976". If the *Overlap* file is +not submitted by the user, the SCC will get the full overlap height from +SCC\_DB and it will produce optical results starting from this height. +If *Lidar Ratio* file is not submitted by the user, the SCC will +consider a fixed value for lidar ratio got from SCC\_DB. + +The user can decide to submit all these files or any number of them (of +course the file *Raw Lidar Data* is mandatory). For example the user can +submit together with the *Raw Lidar Data* file only the *Sounding Data* +file or only the *Overlap* file. + +This document provides a detailed example about the structure of +the NetCDF input files to use for SCC data submission. All Earlinet +groups should read it carefully because they have to produce such kind +of input files if they want to use the SCC for their standard lidar +retrievals. + +Additionaly, the linked :download:`pdf file <../files/NetCDF_input_file_v3.pdf>` contains +tables with all mandatory and optional variables for the netcdf files +accepted by the SCC. Table 1 contains a list of dimensions, variables and +global attributes that can be used in the NetCDF *Raw Lidar Data* +input file. For each of them it is indicated: + +- The name. For the multidimensional variables also the corresponding + dimensions are reported + +- A description explaining the meaning + +- The type + +- If it is mandatory or optional + +As already mentioned, the SCC can get some parameters looking first in +the *Raw Lidar Data* input file and then into SCC\_DB. This means that +to use the parameters stored in SCC\_DB the optional variables or +optional global attributes must not appear within *Raw Lidar Data* file. +This is the suggested and recommended way to use the SCC. Please include +optional parameters in the *Raw Lidar Data* only as an exception. + +Tables 2, 3, and 4 report all the +information about the structure of *Sounding Data*, *Overlap* and *Lidar +Ratio* input files respectively. + + +Example +------- + +Let's now consider an example of *Raw Lidar Data* input file. Suppose +we want to generate NetCDF input file corresponding to a measurement +with the following properties: + ++----------------------+-------------------------------------------+ +| Start Date | 30\ :sup:`th` January 2009 | ++----------------------+-------------------------------------------+ +| Start Time UT | 00:00:01 | ++----------------------+-------------------------------------------+ +| Stop Time UT | 00:05:01 | ++----------------------+-------------------------------------------+ +| Station Name | Dummy station | ++----------------------+-------------------------------------------+ +| Earlinet call-sign | cc | ++----------------------+-------------------------------------------+ +| Pointing angle | 5 degrees with respect to the zenith | ++----------------------+-------------------------------------------+ + + +Moreover suppose that this measurement is composed by the following +lidar channels: + +#. 1064 lidar channel + + +------------------------------+-------------------------------+ + | Emission wavelength=1064nm | Detection wavelength=1064nm | + +------------------------------+-------------------------------+ + | Time resolution=30s | Number of laser shots=1500 | + +------------------------------+-------------------------------+ + | Number of bins=3000 | Detection mode=analog | + +------------------------------+-------------------------------+ + | Range resolution=7.5m | Polarization state=total | + +------------------------------+-------------------------------+ + +#. 532 cross lidar channel + + +-----------------------------+------------------------------------------+ + | Emission wavelength=532nm | Detection wavelength=532nm | + +-----------------------------+------------------------------------------+ + | Time resolution=60s | Number of laser shots=3000 | + +-----------------------------+------------------------------------------+ + | Number of bins=5000 | Detection mode=photoncounting | + +-----------------------------+------------------------------------------+ + | Range resolution=15m | Polarization state=cross (transmitted) | + +-----------------------------+------------------------------------------+ + +#. 532 parallel lidar channel + + +-----------------------------+-------------------------------------------+ + | Emission wavelength=532nm | Detection wavelength=532nm | + +-----------------------------+-------------------------------------------+ + | Time resolution=60s | Number of laser shots=3000 | + +-----------------------------+-------------------------------------------+ + | Number of bins=5000 | Detection mode=photoncounting | + +-----------------------------+-------------------------------------------+ + | Range resolution=15m | Polarization state=parallel (reflected) | + +-----------------------------+-------------------------------------------+ + +#. | 607 :math:`N_2` vibrational Raman channel + + +-----------------------------+---------------------------------+ + | Emission wavelength=532nm | Detection wavelength=607nm | + +-----------------------------+---------------------------------+ + | Time resolution=60s | Number of laser shots=3000 | + +-----------------------------+---------------------------------+ + | Number of bins=5000 | Detection mode=photoncounting | + +-----------------------------+---------------------------------+ + | Range resolution=15m | | + +-----------------------------+---------------------------------+ + +Finally let's assume we have also performed dark measurements before the +lidar measurements from the 23:50:01 UT up to 23:53:01 UT of +29\ :sup:`th` January 2009. + + +Dimensions +~~~~~~~~~~ + +Looking at table 1 of the pdf file we have to fix the following dimensions: + +:: + + points + channels + time + nb_of_time_scales + scan_angles + time_bck + +The dimension ``time`` is unlimited so we don’t have to fix it. +We have 4 lidar channels so: + +:: + + channels=4 + +Regarding the dimension ``points`` we have only one channel with a +number of vertical bins equal to 3000 (the 1064nm) and all other +channels with 5000 vertical bins. In cases like this the dimension +``points`` has to be fixed to the maximum number of vertical bins so: + +:: + + points=5000 + +Moreover only one channel (1064nm) is acquired with a time resolution of +30 seconds, all the other channels have a time resolution of 60 seconds. +This means that we have to define two different time scales. We have to +set: + +:: + + nb_of_time_scales=2 + +The measurement is performed only at one scan angle (5 degrees with +respect to the zenith) so: + +:: + + scan_angles=1 + +We have 3 minutes of dark measurements and two different time scales one +with 60 seconds time resolution and the other one with 30 seconds time +resolution. So we will have 3 different dark profiles for the channels +acquired with the first time scale and 6 for the lidar channels acquired +with the second time scale. We have to fix the dimension ``time_bck`` as +the maximum between these values: + +:: + + time_bck=6 + + +Variables +~~~~~~~~~ + +In this section it will be explained how to fill all the possible +variables either mandatory or optional of *Raw Lidar Data* input file. + +- | ``Raw_Data_Start_Time(time, nb_of_time_scales)`` + | This 2 dimensional mandatory array has to contain the acquisition + start time (in seconds from the time given by the global attribute + ``RawData_Start_Time_UT``) of each lidar profile. In this example + we have two different time scales: one is characterized by steps of + 30 seconds (the 1064nm is acquired with this time scale) the other + by steps of 60 seconds (532cross, 532parallel and 607nm). Moreover + the measurement start time is 00:00:01 UT and the measurement stop + time is 00:05:01 UT. In this case we have to define: + + :: + + Raw_Data_Start_Time = + 0, 0, + 60, 30, + 120, 60, + 180, 90, + 240, 120, + _, 150, + _, 180, + _, 210, + _, 240, + _, 270 ; + + The order used to fill this array defines the correspondence between + the different time scales and the time scale index. In this example + we have a time scale index of 0 for the time scale with steps of 60 + seconds and a time scale index of 1 for the other one. + +- | ``Raw_Data_Stop_Time(time, nb_of_time_scales)`` + | The same as previous item but for the data acquisition stop time. + Following a similar procedure we have to define: + + :: + + Raw_Data_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + 240, 120, + 300, 150, + _, 180, + _, 210, + _, 240, + _, 270, + _, 300 ; + +- | ``Raw_Lidar_Data(time, channels, points)`` + | This 3 dimensional mandatory array has to be filled with the + time-series of raw lidar data. The photoncounting profiles have to + submitted in counts (so as integers) while the analog ones in mV. + The order the user chooses to fill this array defines the + correspondence between channel index and lidar data. + | For example if we fill this array in such way that: + + +-------------------------------------+---------------------------------------+ + | ``Raw_Lidar_Data(time,0,points)`` | is the time-series of 1064 nm | + +-------------------------------------+---------------------------------------+ + | ``Raw_Lidar_Data(time,1,points)`` | is the time-series of 532 cross | + +-------------------------------------+---------------------------------------+ + | ``Raw_Lidar_Data(time,2,points)`` | is the time-series of 532 parallel | + +-------------------------------------+---------------------------------------+ + | ``Raw_Lidar_Data(time,3,points)`` | is the time-series of 607 nm | + +-------------------------------------+---------------------------------------+ + + | + | from now on the channel index 0 is associated to the 1064 channel, + 1 to the 532 cross, 2 to the 532 parallel and 3 to the 607nm. + +- | ``Raw_Bck_Start_Time(time_bck, nb_of_time_scales)`` + | This 2 dimensional optional array has to contain the acquisition + start time (in seconds from the time given by the global attribute + ``RawBck_Start_Time_UT``) of each dark measurements profile. + Following the same procedure used for the variable + ``Raw_Data_Start_Time`` we have to define: + + :: + + Raw_Bck_Start_Time = + 0, 0, + 60, 30, + 120, 60, + _, 90, + _, 120, + _, 150; + +- | ``Raw_Bck_Stop_Time(time_bck, nb_of_time_scales)`` + | The same as previous item but for the dark acquisition stop time. + Following a similar procedure we have to define: + + :: + + Raw_Bck_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + _, 120, + _, 150, + _, 180 ; + +- | ``Background_Profile(time_bck, channels, points)`` + | This 3 dimensional optional array has to be filled with the + time-series of the dark measurements data. The photoncounting + profiles have to submitted in counts (so as integers) while the + analog ones in mV. The user has to fill this array following the + same order used in filling the array ``Raw_Lidar_Data``: + + +---------------------------------------------+-------------------------------------+ + | ``Background_Profile(time_bck,0,points)`` | dark time-series at 1064 nm | + +---------------------------------------------+-------------------------------------+ + | ``Background_Profile(time_bck,1,points)`` | dark time-series at 532 cross | + +---------------------------------------------+-------------------------------------+ + | ``Background_Profile(time_bck,2,points)`` | dark time-series at 532 parallel | + +---------------------------------------------+-------------------------------------+ + | ``Background_Profile(time_bck,3,points)`` | dark time-series at 607 nm | + +---------------------------------------------+-------------------------------------+ + + | + +- | ``channel_ID(channels)`` + | This mandatory array provides the link between the channel index + within the *Raw Lidar Data* input file and the channel ID in + SCC\_DB. To fill this variable the user has to know which channel + IDs in SCC\_DB correspond to his lidar channels. For this purpose + the SCC, in its final version will provide to the user a special + tool to get these channel IDs through a Web interface. At the + moment this interface is not yet available and these channel IDs + will be communicated directly to the user by the NA5 people. + | Anyway to continue the example let’s suppose that the four lidar + channels taken into account are mapped into SCC\_DB with the + following channel IDs: + + +----------------+-----------------+ + | 1064 nm | channel ID=7 | + +----------------+-----------------+ + | 532 cross | channel ID=5 | + +----------------+-----------------+ + | 532 parallel | channel ID=6 | + +----------------+-----------------+ + | 607 nm | channel ID=8 | + +----------------+-----------------+ + + | + | In this case we have to define: + + :: + + channel_ID = 7, 5, 6, 8 ; + +- | ``id_timescale(channels)`` + | This mandatory array is introduced to determine which time scale is + used for the acquisition of each lidar channel. In particular this + array defines the link between the channel index and the time scale + index. In our example we have two different time scales. Filling + the arrays ``Raw_Data_Start_Time`` and ``Raw_Data_Stop_Time`` we + have defined a time scale index of 0 for the time scale with steps + of 60 seconds and a time scale index of 1 for the other one with + steps of 30 seconds. In this way this array has to be set as: + + :: + + id_timescale = 1, 0, 0, 0 ; + +- | ``Laser_Pointing_Angle(scan_angles)`` + | This mandatory array contains all the scan angles used in the + measurement. In our example we have only one scan angle of 5 + degrees with respect to the zenith, so we have to define: + + :: + + Laser_Pointing_Angle = 5 ; + +- | ``Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales)`` + | This mandatory array is introduced to determine which scan angle is + used for the acquisition of each lidar profile. In particular this + array defines the link between the time and time scales indexes and + the scan angle index. In our example we have a single scan angle + that has to correspond to the scan angle index 0. So this array has + to be defined as: + + :: + + Laser_Pointing_Angle_of_Profiles = + 0, 0, + 0, 0, + 0, 0, + 0, 0, + 0, 0, + _, 0, + _, 0, + _, 0, + _, 0, + _, 0 ; + +- | ``Laser_Shots(time, channels)`` + | This mandatory array stores the laser shots accumulated at each + time for each channel. In our example the number of laser shots + accumulated is 1500 for the 1064nm channels and 3000 for all the + other channels. Moreover the laser shots do not change with the + time. So we have to define this array as: + + :: + + Laser_Shots = + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _ ; + +- | ``Emitted_Wavelength(channels)`` + | This optional array defines the link between the channel index and + the emission wavelength for each lidar channel. The wavelength has + to be expressed in nm. This information can be also taken from + SCC\_DB. In our example we have: + + :: + + Emitted_Wavelength = 1064, 532, 532, 532 ; + +- | ``Detected_Wavelength(channels)`` + | This optional array defines the link between the channel index and + the detected wavelength for each lidar channel. Here detected + wavelength means the value of center of interferential filter + expressed in nm. This information can be also taken from SCC\_DB. + In our example we have: + + :: + + Detected_Wavelength = 1064, 532, 532, 607 ; + +- | ``Raw_Data_Range_Resolution(channels)`` + | This optional array defines the link between the channel index and + the raw range resolution for each channel. If the scan angle is + different from zero this quantity is different from the vertical + resolution. More precisely if :math:`\alpha` is the scan angle used + and :math:`\Delta z` is the range resolution the vertical + resolution is calculated as :math:`\Delta + z'=\Delta z \cos\alpha`. This array has to be filled with + :math:`\Delta z` and not with :math:`\Delta z'`. The unit is + meters. This information can be also taken from SCC\_DB. In our + example we have: + + :: + + Raw_Data_Range_Resolution = 7.5, 15.0, 15.0, 15.0 ; + +- | ``Scattering_Mechanism(channels)`` + | This optional array defines the scattering mechanism involved in + each lidar channel. In particular the following values are adopted: + + +-----+---------------------------------------------------+ + | 0 | Total elastic backscatter | + +-----+---------------------------------------------------+ + | 1 | N\ :math:`_2` vibrational Raman backscatter | + +-----+---------------------------------------------------+ + | 2 | Cross polarization elastic backscatter | + +-----+---------------------------------------------------+ + | 3 | Parallel polarization elastic backscatter | + +-----+---------------------------------------------------+ + | 4 | H\ :math:`_2`\ O vibrational Raman backscatter | + +-----+---------------------------------------------------+ + | 5 | Rotational Raman low quantum number | + +-----+---------------------------------------------------+ + | 6 | Rotational Raman high quantum number | + +-----+---------------------------------------------------+ + + | + | This information can be also taken from SCC\_DB. In our example we + have: + + :: + + Scattering_Mechanism = 0, 2, 3, 1 ; + +- | ``Signal_Type(channels)`` + | This optional array defines the type of signal involved in each + lidar channel. In particular the following values are adopted: + + +------+--------------------------------------------------------------+ + | 0 | Total elastic | + +------+--------------------------------------------------------------+ + | 1 | Total elastic near range | + +------+--------------------------------------------------------------+ + | 2 | Total elastic far range | + +------+--------------------------------------------------------------+ + | 3 | N\ :math:`_2` vibrational Raman | + +------+--------------------------------------------------------------+ + | 4 | N\ :math:`_2` vibrational Raman near range | + +------+--------------------------------------------------------------+ + | 5 | N\ :math:`_2` vibrational Raman far range | + +------+--------------------------------------------------------------+ + | 6 | Elastic polarization reflected | + +------+--------------------------------------------------------------+ + | 7 | Elastic polarization transmitted | + +------+--------------------------------------------------------------+ + | 8 | Rotational Raman line close to elastic line | + +------+--------------------------------------------------------------+ + | 9 | Rotational Raman line far from elastic line | + +------+--------------------------------------------------------------+ + | 10 | Elastic polarization reflected near range | + +------+--------------------------------------------------------------+ + | 11 | Elastic polarization reflected far range | + +------+--------------------------------------------------------------+ + | 12 | Elastic polarization transmitted near range | + +------+--------------------------------------------------------------+ + | 13 | Elastic polarization transmitted far range | + +------+--------------------------------------------------------------+ + | 14 | H\ :math:`_2`\ O vibrational Raman backscatter | + +------+--------------------------------------------------------------+ + | 15 | Rotational Raman line far from elastic line near range | + +------+--------------------------------------------------------------+ + | 16 | Rotational Raman line far from elastic line far range | + +------+--------------------------------------------------------------+ + | 17 | Rotational Raman line close to elastic line near range | + +------+--------------------------------------------------------------+ + | 18 | Rotational Raman line close to elastic line far range | + +------+--------------------------------------------------------------+ + | 19 | H\ :math:`_2`\ O vibrational Raman backscatter near range | + +------+--------------------------------------------------------------+ + | 20 | H\ :math:`_2`\ O vibrational Raman backscatter far range | + +------+--------------------------------------------------------------+ + | 21 | Total elastic ultra near range | + +------+--------------------------------------------------------------+ + | 22 | +45 rotated elastic polarization transmitted | + +------+--------------------------------------------------------------+ + | 23 | +45 rotated elastic polarization reflected | + +------+--------------------------------------------------------------+ + | 24 | -45 rotated elastic polarization transmitted | + +------+--------------------------------------------------------------+ + | 25 | -45 rotated elastic polarization reflected | + +------+--------------------------------------------------------------+ + | 26 | +45 rotated elastic polarization transmitted near range | + +------+--------------------------------------------------------------+ + | 27 | +45 rotated elastic polarization transmitted far range | + +------+--------------------------------------------------------------+ + | 28 | +45 rotated elastic polarization reflected near range | + +------+--------------------------------------------------------------+ + | 29 | +45 rotated elastic polarization reflected far range | + +------+--------------------------------------------------------------+ + | 30 | -45 rotated elastic polarization transmitted near range | + +------+--------------------------------------------------------------+ + | 31 | -45 rotated elastic polarization transmitted far range | + +------+--------------------------------------------------------------+ + | 32 | -45 rotated elastic polarization reflected near range | + +------+--------------------------------------------------------------+ + | 33 | -45 rotated elastic polarization reflected far range | + +------+--------------------------------------------------------------+ + + | + | This information can be also taken from SCC\_DB. In our example we + have: + + :: + + Signal_Type = 0, 7, 6, 3 ; + +- | ``Acquisition_Mode(channels)`` + | This optional array defines the acquisition mode (analog or + photoncounting) involved in each lidar channel. In particular a + value of 0 means analog mode and 1 photoncounting mode. This + information can be also taken from SCC\_DB. In our example we have: + + :: + + Acquisition_Mode = 0, 1, 1, 1 ; + +- | ``Laser_Repetition_Rate(channels)`` + | This optional array defines the repetition rate in Hz used to + acquire each lidar channel. This information can be also taken from + SCC\_DB. In our example we are supposing we have only one laser + with a repetition rate of 50 Hz so we have to set: + + :: + + Laser_Repetition_Rate = 50, 50, 50, 50 ; + +- | ``Dead_Time(channels)`` + | This optional array defines the dead time in ns associated to each + lidar channel. The SCC will use the values given by this array to + correct the photoncounting signals for dead time. Of course for + analog signals no dead time correction will be applied (for analog + channels the corresponding dead time values have to be set to + undefined value). This information can be also taken from SCC\_DB. + In our example the 1064 nm channel is acquired in analog mode so + the corresponding dead time value has to be undefined. If we + suppose a dead time of 10 ns for all other channels we have to set: + + :: + + Dead_Time = _, 10, 10, 10 ; + +- | ``Dead_Time_Corr_Type(channels)`` + | This optional array defines which kind of dead time correction has + to be applied on each photoncounting channel. The SCC will correct + the data supposing a not-paralyzable channel if a value of 0 is + found while a paralyzable channel is supposed if a value of 1 is + found. Of course for analog signals no dead time correction will be + applied and so the corresponding values have to be set to undefined + value. This information can be also taken from SCC\_DB. In our + example the 1064 nm channel is acquired in analog mode so the + corresponding has to be undefined. If we want to consider all the + photoncounting signals as not-paralyzable ones: we have to set: + + :: + + Dead_Time_Corr_Type = _, 0, 0, 0 ; + +- | ``Trigger_Delay(channels)`` + | This optional array defines the delay (in ns) of the middle of the + first rangebin with respect to the output laser pulse for each + lidar channel. The SCC will use the values given by this array to + correct for trigger delay. This information can be also taken from + SCC\_DB. Let’s suppose that in our example all the photoncounting + channels are not affected by this delay and only the analog channel + at 1064nm is acquired with a delay of 50ns. In this case we have to + set: + + :: + + Trigger_Delay = 50, 0, 0, 0 ; + +- | ``Background_Mode(channels)`` + | This optional array defines how the atmospheric background has to + be subtracted from the lidar channel. Two options are available for + the calculation of atmospheric background: + + #. Average in the far field of lidar channel. In this case the value + of this variable has to be 1 + + #. Average within pre-trigger bins. In this case the value of this + variable has to be 0 + + This information can be also taken from SCC\_DB. Let’s suppose in our + example we use the pre-trigger for the 1064nm channel and the far + field for all other channels. In this case we have to set: + + :: + + Background_Mode = 0, 1, 1, 1 ; + +- | ``Background_Low(channels)`` + | This mandatory array defines the minimum altitude (in meters) to + consider in calculating the atmospheric background for each + channel. In case pre-trigger mode is used the corresponding value + has to be set to the rangebin to be used as lower limit (within + pre-trigger region) for background calculation. In our example, if + we want to calculate the background between 30000 and 50000 meters + for all photoncounting channels and we want to use the first 500 + pre-trigger bins for the background calculation for the 1064nm + channel we have to set: + + :: + + Background_Low= 0, 30000, 30000, 30000 ; + +- | ``Background_High(channels)`` + | This mandatory array defines the maximum altitude (in meters) to + consider in calculating the atmospheric background for each + channel. In case pre-trigger mode is used the corresponding value + has to be set to the rangebin to be used as upper limit (within + pre-trigger region) for background calculation. In our example, if + we want to calculate the background between 30000 and 50000 meters + for all photoncounting channels and we want to use the first 500 + pre-trigger bins for the background calculation for the 1064nm + channel we have to set: + + :: + + Background_High = 500, 50000, 50000, 50000 ; + +- | ``Molecular_Calc`` + | This mandatory variable defines the way used by SCC to calculate + the molecular density profile. At the moment two options are + available: + + #. US Standard Atmosphere 1976. In this case the value of this + variable has to be 0 + + #. Radiosounding. In this case the value of this variable has to be 1 + + If we decide to use the option 1. we have to provide also the + measured pressure and temperature at lidar station level. Indeed if + we decide to use the option 2. a radiosounding file has to be + submitted separately in NetCDF format (the structure of this file is + summarized in table 2 of the pdf file). Let’s suppose we want to use the + option 1. so: + + :: + + Molecular_Calc = 0 ; + +- | ``Pressure_at_Lidar_Station`` + | Because we have chosen the US Standard Atmosphere for calculation + of the molecular density profile we have to give the pressure in + hPa at lidar station level: + + :: + + Pressure_at_Lidar_Station = 1010 ; + +- | ``Temperature_at_Lidar_Station`` + | Because we have chosen the US Standard Atmosphere for calculation + of the molecular density profile we have to give the temperature in + C at lidar station level: + + :: + + Temperature_at_Lidar_Station = 19.8 ; + +- | ``LR_Input(channels)`` + | This array is required only for lidar channels for which elastic + backscatter retrieval has to be performed. It defines the lidar + ratio to be used within this retrieval. Two options are available: + + #. The user can submit a lidar ratio profile. In this case the value + of this variable has to be 0. + + #. A fixed value of lidar ratio can be used. In this case the value + of this variable has to be 1. + + If we decide to use the option 1. a lidar ratio file has to be + submitted separately in NetCDF format (the structure of this file is + summarized in table ). If we decide to use the option 2. the + fixed value of lidar ratio will be taken from SCC\_DB. In our example + we have to give a value of this array only for the 1064nm lidar + channel because for the 532nm we will be able to retrieve a Raman + backscatter coefficient. In case we want to use the fixed value + stored in SCC\_DB we have to set: + + :: + + LR_Input = 1,_,_,_ ; + +- | ``DAQ_Range(channels)`` + | This array is required only if one or more lidar signals are + acquired in analog mode. It gives the analog scale in mV used to + acquire the analog signals. In our example we have only the 1064nm + channel acquired in analog mode. If we have used a 100mV analog + scale to acquire this channel we have to set: + + :: + + DAQ_Range = 100,_,_,_ ; + + +Global attributes +~~~~~~~~~~~~~~~~~ + +- | ``Measurement_ID`` + | This mandatory global attribute defines the measurement ID + corresponding to the actual lidar measurement. It is a string + composed by 12 characters. The first 8 characters give the start + date of measurement in the format YYYYMMDD. The next 2 characters + give the Earlinet call-sign of the station. The last 2 characters + are used to distinguish between different time-series within the + same date. In our example we have to set: + + :: + + Measurement_ID= "20090130cc00" ; + +- | ``RawData_Start_Date`` + | This mandatory global attribute defines the start date of lidar + measurements in the format YYYYMMDD. In our case we have: + + :: + + RawData_Start_Date = "20090130" ; + +- | ``RawData_Start_Time_UT`` + | This mandatory global attribute defines the UT start time of lidar + measurements in the format HHMMSS. In our case we have: + + :: + + RawData_Start_Time_UT = "000001" ; + +- | ``RawData_Stop_Time_UT`` + | This mandatory global attribute defines the UT stop time of lidar + measurements in the format HHMMSS. In our case we have: + + :: + + RawData_Stop_Time_UT = "000501" ; + +- | ``RawBck_Start_Date`` + | This optional global attribute defines the start date of dark + measurements in the format YYYYMMDD. In our case we have: + + :: + + RawBck_Start_Date = "20090129" ; + +- | ``RawBck_Start_Time_UT`` + | This optional global attribute defines the UT start time of dark + measurements in the format HHMMSS. In our case we have: + + :: + + RawBck_Start_Time_UT = "235001" ; + +- | ``RawBck_Stop_Time_UT`` + | This optional global attribute defines the UT stop time of dark + measurements in the format HHMMSS. In our case we have: + + :: + + RawBck_Stop_Time_UT = "235301" ; + + +Example of file (CDL format) +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +To summarize we have the following NetCDF *Raw Lidar Data* file (in CDL +format): + +:: + + dimensions: + points = 5000 ; + channels = 4 ; + time = UNLIMITED ; // (10 currently) + nb_of_time_scales = 2 ; + scan_angles = 1 ; + time_bck = 6 ; + variables: + int channel_ID(channels) ; + int Laser_Repetition_Rate(channels) ; + double Laser_Pointing_Angle(scan_angles) ; + int Signal_Type(channels); + double Emitted_Wavelength(channels) ; + double Detected_Wavelength(channels) ; + double Raw_Data_Range_Resolution(channels) ; + int Background_Mode(channels) ; + double Background_Low(channels) ; + double Background_High(channels) ; + int Molecular_Calc ; + double Pressure_at_Lidar_Station ; + double Temperature_at_Lidar_Station ; + int id_timescale(channels) ; + double Dead_Time(channels) ; + int Dead_Time_Corr_Type(channels) ; + int Acquisition_Mode(channels) ; + double Trigger_Delay(channels) ; + int LR_Input(channels) ; + int Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales) ; + int Raw_Data_Start_Time(time, nb_of_time_scales) ; + int Raw_Data_Stop_Time(time, nb_of_time_scales) ; + int Raw_Bck_Start_Time(time_bck, nb_of_time_scales) ; + int Raw_Bck_Stop_Time(time_bck, nb_of_time_scales) ; + int Laser_Shots(time, channels) ; + double Raw_Lidar_Data(time, channels, points) ; + double Background_Profile(time_bck, channels, points) ; + double DAQ_Range(channels) ; + + // global attributes: + :Measurement_ID = "20090130cc00" ; + :RawData_Start_Date = "20090130" ; + :RawData_Start_Time_UT = "000001" ; + :RawData_Stop_Time_UT = "000501" ; + :RawBck_Start_Date = "20090129" ; + :RawBck_Start_Time_UT = "235001" ; + :RawBck_Stop_Time_UT = "235301" ; + + data: + + channel_ID = 7, 5, 6, 8 ; + + Laser_Repetition_Rate = 50, 50, 50, 50 ; + + Laser_Pointing_Angle = 5 ; + + Signal_Type = 0, 7, 6, 3 ; + + Emitted_Wavelength = 1064, 532, 532, 532 ; + + Detected_Wavelength = 1064, 532, 532, 607 ; + + Raw_Data_Range_Resolution = 7.5, 15, 15, 15 ; + + Background_Mode = 0, 1, 1, 1 ; + + Background_Low = 0, 30000, 30000, 30000 ; + + Background_High = 500, 50000, 50000, 50000 ; + + Molecular_Calc = 0 ; + + Pressure_at_Lidar_Station = 1010 ; + + Temperature_at_Lidar_Station = 19.8 ; + + id_timescale = 1, 0, 0, 0 ; + + Dead_Time = _, 10, 10, 10 ; + + Dead_Time_Corr_Type = _, 0, 0, 0 ; + + Acquisition_Mode = 0, 1, 1, 1 ; + + Trigger_Delay = 50, 0, 0, 0 ; + + LR_Input = 1,_,_,_ ; + + DAQ_Range = 100,_,_,_ ; + + Laser_Pointing_Angle_of_Profiles = + 0, 0, + 0, 0, + 0, 0, + 0, 0, + 0, 0, + _, 0, + _, 0, + _, 0, + _, 0, + _, 0 ; + + + Raw_Data_Start_Time = + 0, 0, + 60, 30, + 120, 60, + 180, 90, + 240, 120, + _, 150, + _, 180, + _, 210, + _, 240, + _, 270 ; + + Raw_Data_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + 240, 120, + 300, 150, + _, 180, + _, 210, + _, 240, + _, 270, + _, 300 ; + + + Raw_Bck_Start_Time = + 0, 0, + 60, 30, + 120, 60, + _, 90, + _, 120, + _, 150; + + + Raw_Bck_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + _, 120, + _, 150, + _, 180 ; + + + Laser_Shots = + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _ ; + + + Raw_Lidar_Data = ... + + Background_Profile = ... + +The name of the input file should have the following format: + +:: + + Measurement_ID.nc + +| so in the example the filename should be 20090130cc00.nc. + +Please keep in mind that in case you submit a file like the previous +one all the parameters present in it will be used by the SCC even if +you have different values for the same parameters within the SCC\_DB. +If you want to use the values already stored in SCC\_DB (this should +be the usual way to use SCC) the *Raw Lidar Data* input file has to be +modified as follows: + +:: + + dimensions: + points = 5000 ; + channels = 4 ; + time = UNLIMITED ; // (10 currently) + nb_of_time_scales = 2 ; + scan_angles = 1 ; + time_bck = 6 ; + variables: + int channel_ID(channels) ; + double Laser_Pointing_Angle(scan_angles) ; + double Background_Low(channels) ; + double Background_High(channels) ; + int Molecular_Calc ; + double Pressure_at_Lidar_Station ; + double Temperature_at_Lidar_Station ; + int id_timescale(channels) ; + int Laser_Pointing_Angle_of_Profiles(time, nb_of_time_scales) ; + int Raw_Data_Start_Time(time, nb_of_time_scales) ; + int Raw_Data_Stop_Time(time, nb_of_time_scales) ; + int Raw_Bck_Start_Time(time_bck, nb_of_time_scales) ; + int Raw_Bck_Stop_Time(time_bck, nb_of_time_scales) ; + int LR_Input(channels) ; + int Laser_Shots(time, channels) ; + double Raw_Lidar_Data(time, channels, points) ; + double Background_Profile(time_bck, channels, points) ; + double DAQ_Range(channels) ; + + // global attributes: + :Measurement_ID = "20090130cc00" ; + :RawData_Start_Date = "20090130" ; + :RawData_Start_Time_UT = "000001" ; + :RawData_Stop_Time_UT = "000501" ; + :RawBck_Start_Date = "20090129" ; + :RawBck_Start_Time_UT = "235001" ; + :RawBck_Stop_Time_UT = "235301" ; + + data: + + channel_ID = 7, 5, 6, 8 ; + + Laser_Pointing_Angle = 5 ; + + Background_Low = 0, 30000, 30000, 30000 ; + + Background_High = 500, 50000, 50000, 50000 ; + + Molecular_Calc = 0 ; + + Pressure_at_Lidar_Station = 1010 ; + + Temperature_at_Lidar_Station = 19.8 ; + + id_timescale = 1, 0, 0, 0 ; + + LR_Input = 1,_,_,_ ; + + DAQ_Range = 100,_,_,_ ; + + Laser_Pointing_Angle_of_Profiles = + 0, 0, + 0, 0, + 0, 0, + 0, 0, + 0, 0, + _, 0, + _, 0, + _, 0, + _, 0, + _, 0 ; + + + Raw_Data_Start_Time = + 0, 0, + 60, 30, + 120, 60, + 180, 90, + 240, 120, + _, 150, + _, 180, + _, 210, + _, 240, + _, 270 ; + + Raw_Data_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + 240, 120, + 300, 150, + _, 180, + _, 210, + _, 240, + _, 270, + _, 300 ; + + + Raw_Bck_Start_Time = + 0, 0, + 60, 30, + 120, 60, + _, 90, + _, 120, + _, 150; + + + Raw_Bck_Stop_Time = + 60, 30, + 120, 60, + 180, 90, + _, 120, + _, 150, + _, 180 ; + + + Laser_Shots = + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, 3000, 3000, 3000, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _, + 1500, _, _, _ ; + + + Raw_Lidar_Data = ... + + Background_Profile = ... + +This example file contains the minimum collection of mandatory +information that has to be found within the *Raw Lidar Data* input file. +If it is really necessary, the user can decide to add to these mandatory +parameters any number of additional parameters considered in the +previous example. + +Finally, suppose we want to make the following changes with respect to +the previous example: + +#. use a sounding file for molecular density calculation instead of “US + Standar Atmosphere 1976” + +#. supply a lidar ratio profile to use in elastic backscatter retrieval + instead of a fixed value + +#. provide a overlap function for overlap correction + +In this case we have to generate the following NetCDF additional files: + +- | ``rs_20090130cc00.nc`` + | The name of *Sounding Data* file has to be computed as follows: + | ``"rs_"``\ +\ ``Measurement_ID`` + | The structure of this file is summarized in table 2 of the pdf. + +- | ``ov_20090130cc00.nc`` + | The name of *Overlap* file has to be computed as follows: + | ``"ov_"``\ +\ ``Measurement_ID`` + | The structure of this file is summarized in table 3 of the pdf. + +- | ``lr_20090130cc00.nc`` + | The name of *Lidar Ratio* file has to be computed as follows: + | ``"lr_"``\ +\ ``Measurement_ID`` + | The structure of this file is summarized in table 4 of the pdf. + +Moreover we need to apply the following changes to the *Raw Lidar Data* +input file: + +#. Change the value of the variable ``Molecular_Calc`` as follows: + + :: + + Molecular_Calc = 1 ; + + Of course the variables ``Pressure_at_Lidar_Station`` and + ``Temperature_at_Lidar_Station`` are not necessary anymore. + +#. Change the values of the array ``LR_Input`` as follows: + + :: + + LR_Input = 0,_,_,_ ; + +#. Add the global attribute ``Sounding_File_Name`` + + :: + + Sounding_File_Name = "rs_20090130cc00.nc" ; + +#. Add the global attribute ``LR_File_Name`` + + :: + + LR_File_Name = "lr_20090130cc00.nc" ; + +#. Add the global attribute ``Overlap_File_Name`` + + :: + + Overlap_File_Name = "ov_20090130cc00.nc" ; +
