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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*
    :Dimensions: *scan\_angles*
    :Location: Included in all the Low Resolution SCC L1 Product files
    :Definition: ``double altitude_resolution(scan_angles)``
    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:
        
    .. math::
            
        H(\alpha, z)= \Delta h(\alpha)\left(z + \frac{1}{2}\right)
            
    where *z* is the altitude, :math:`\alpha` is the scan angle value and :math:`\Delta h` is the
    value reported by *altitude\_resolution* variable.

range\_resolution
    :Type: *double*
    :Dimensions: *scan\_angles*
    :Location: Included in all the Low Resolution SCC L1 Product files
    :Definition: ``double range_resolution(scan_angles)``
    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:

    .. math::
                
            R(\alpha, z)= \Delta r(\alpha)\left(r + \frac{1}{2}\right)
            
    where *r* is the range, :math:`\alpha` is the scan angle value and :math:`\Delta 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            |
+--------------------------------------------------------------+---------------------------------------------------+