POLDER 2 - List of Parameters in POLDER "ERB, WV & CLOUDS"

The following geophysical parameters are computed from the level 1 product for each superpixel (3x3 pixels), by orbit segment.
For details about the calculation of these parameters, see POLDER2 advanced algorithms.

(a) Level 2 non-directional parameters

Parameter	Definition	Unit	Range
th tm	GMT time	h mm	0-23 0-59
Ni	Total number of viewing directions	-	0-14
Nr Np	Number of viewing directions used for the Rayleigh pressure derivation Number of elementary pixels	- -	0-14 0-12
MinGlitter MaxGlitter	No of the first / last viewing direction within the expected region of solar specular reflection	- -	0-14 0-14
µs	Cosine of solar zenith angle (defined for the central elementary pixel)	-	0-1
Avis	Mean albedo at 670 nm over land and 865 nm over ocean, result from an averaging over pixels and a weighting over directions	-	0-1
RSD(Avis)	Relative Spatial standard Deviation of the albedos derived by pixel and by direction at 670/865 nm	%	0-50
RAD(Avis)	Relative Angular standard Deviation of the albedos derived by pixel and by direction at 670/865 nm	%	0-50
QAvis	Quality index related to the ratio between the relative angular deviation RAD(Avis) and that derived under the Lambertian hypothesis. It ranges from 0 (default) to 1 (ideal case)	-	0-1
A*vis	Mean of the albedos calculated under the assumption of an homogeneous scene at 670/865 nm	-	0-1
RAD(A*vis)	Relative Angular standard Deviation of the albedos at 670/865 nm calculated under the assumption of an homogeneous scene	%	0-50
[Amodel(c=0)]vis	Modeled clear-sky albedo at 670/865 nm, that is independent of POLDER measurements	-	0-1
ASW	Shortwave albedo derived from the 443, 670 and 865 nm albedos	-	0-1
[Amodel(c=0)]SW	Modeled clear-sky shortwave albedo, that is independent of POLDER measurements	-	0-1
CC	Cloud Cover, defined as the number of cloudy pixels divided by the total number of pixels.	-	0-1
CC+ CC-	Uncertainty on cloud cover related to re-classification, i.e. number of pixels firstly classified as indeterminate and finally classified as clear (+) /cloudy (-) divided by the total number of pixels	- -	0-1 0-1
QCC	Quality index related to cloud detection. It ranges from 0 (very bad) to 1 (very good)	-	0-1
UH2O	Total column precipitable water vapor of the clear part of the superpixel	g cm-²	0-7.5
SD(UH2O)	Standard Deviation of water vapor estimates	g cm-²	0-2.5
Poxy	Mean cloud Oxygen pressure. It is expected to be close to the cloud middle pressure	hPa	0-1200
AD(Poxy)	Angular standard Deviation of the cloud Oxygen pressure derived by direction	hPa	0-625
Pray	Mean cloud Rayleigh pressure. It is expected to be close to the cloud top pressure	hPa	0-1200
AD(Pray)	Angular standard Deviation of the cloud Rayleigh pressure derived by direction	hPa	0-625
c	Linear mean cloud optical thickness at 670 nm over land and 865 nm over ocean, result from an averaging over cloudy pixels and a weighting over directions	-	0-500
RSD(c)	Relative Spatial standard Deviation of the cloud optical thickness at 670/865 nm	%	0-100
c* / (CC x c)	Ratio between the cloud optical thickness associated to the mean reflectance of the superpixel and the linear mean cloud optical thickness averaged over all the pixels. It is equal to 1 for a homogeneous scene.	-	0-2.5
Sc	Mean cloud spherical albedo (defined over black surface with no atmosphere) at 670/865 nm, result from an averaging over cloudy pixels and a weighting over directions	-	0-1
Phase	Cloud thermodynamic phase	-	0-250
Micro-index	Microphysical index calculated only for ice clouds (currently not available).	-	0-250
strato-aer	Stratospheric aerosol optical thickness (exogeneous data)	-	0-0.225
UO3	Total column ozone (exogeneous data)	cm-atm	0-0.6
Vwind	Meteorological surface wind intensity (exogeneous data)	m-¹	0-50
wind	Meteorological surface wind bearing (exogeneous data)	degrees	0-360
Psurface	Meteorological surface pressure (exogeneous data)	hPa	0-1100
T(k), k=1,10	Meteorological temperature profile reported at ten pressure levels : 1000, 925, 850, 700, 500, 400, 300, 250, 200 and 150 hPa (exogeneous data)	K	150-350
U(k), k=1,10	Meteorological integrated water vapor profile defined from surface level up to pressure levels: 1000, 925, 850, 700, 500, 400, 300, 250, 200 and 0 hPa (exogeneous data)	g cm-²	0-7.5

(b) Level 2 directional parameters

v(i)	Viewing zenith angle (defined for the central elementary pixel) in the given direction (i)	degrees	0-73
(i)	Relative azimutal angle (defined for the central elementary pixel) in the given direction (i)	degrees	-180 - 180
Rvis(i)	Mean of the reflectances corrected from gaseous absorption at 670 nm over land and 865 nm over ocean, result from an averaging over pixels in the given direction (i)	-	0-6.5
Avis(i)	Mean "directional" albedo at 670/865 nm, result from an averaging over pixels in the given direction (i)	-	0-1.0
RSW(i)	Mean shortwave reflectance estimated from narrowband reflectances	-	0-6.5
ASW(i)	Mean shortwave "directional" albedo estimated from narrowband "directional" albedos	-	0-1.0
LPSMOD865(i)	Modified polarized radiance at 865 nm	-	-0.05 - 0.15
Ncloud(i) Nclear(i)	Number of cloudy / clear pixels. Their sum is less than Np when some pixels are unclassified in the given direction	- -	0-12 0-12
CC(i)	Cloud Cover, defined as the number of cloudy (including "unclassified" relabeled as cloudy) pixels divided by the total number of pixels	-	0-1
Sc(i)	Mean cloud spherical albedo (defined over black surface with no atmosphere) at 670/865 nm, result from an averaging over cloudy pixels in the given direction (i)	-	0-1

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