Normalized Water Leaving Radiance(NWLR)

Introduction

NWLR Define The upwelling radiance just above the sea surface.
Unit W/m2/str/um or 1/sr
ATBD Ver.1 (Jan. 2019)
Ver.2 (Jul. 2020)
TAUA Define Aerosol optical properties for the atmospheric correction over ocean.
Unit none
ATBD Ver.1 (Jan. 2019)
Ver.2 (Jul. 2020)
PAR Define Photon flux density within the visible wavelength range (400 to 700 nm) over ocean which is potencially available to plant for photosynthesis.
Unit Ein/m2/day or mol photons/m2/day
ATBD Ver.1 (Jan. 2019)
Ver.2 (Jul. 2020)

Update contents of Ver2

  • ・Improved LUT of aerosol
  • ・Improved sunglint correction
  • ・Improved in-water model
  • ・Modified QA flag
  • ・Applied the vicarious calibration results of ver 2.0

Stored Physical quantity

Ver1,2 Description
Line_tai93 TAI93 at each line
NWLR_380 Normalized Water Leaving Radiance(NWLR) at 380.0 nm
NWLR_412 Normalized Water Leaving Radiance(NWLR) at 412.0 nm
NWLR_443 Normalized Water Leaving Radiance(NWLR) at 443.0 nm
NWLR_490 Normalized Water Leaving Radiance(NWLR) at 490.0 nm
NWLR_530 Normalized Water Leaving Radiance(NWLR) at 530.0 nm
NWLR_565 Normalized Water Leaving Radiance(NWLR) at 565.0 nm
NWLR_670 Normalized Water Leaving Radiance(NWLR) at 673.5 nm
PAR Photosynthetically Available Radiation
QA_flag
TAUA_670 Aerosol Optical Thickness(TauA) at 673.5
TAUA_865 Aerosol Optical Thickness(TauA) at 868.5

QA_flag information

Ver.1 Ver.2 Ver.1(Sample Image) Ver.2(Sample Image)

Bit ver1 Description NWLR_380-670_L3_mask* PAR_L3_mask* TAUA_670,865_L3_mask*
0 DATAMISS No observation data in one or more band[s] 1 1 1
1 LAND Land pixel 1 0 1
2 ATMFAIL Atmospheric correction failure 1 0 1
3 CLDICE Apparent cloud/ice (high reflectance) 1 0 1
4 CLDAFFCTD Cloud-affected (near-cloud or thin/sub-pixel cloud) 1 0 1
5 STRAYLIGHT Stray light anticipated (ref. L1B stray light flags & image) 0 0 0
6 HIGLINT High sun glint predicted (atmospheric corr. abandoned) 1 0 1
7 MODGLINT Moderate sun glint predicted (correction applied) 1 0 1
8 HISOLZ Solar zenith larger than threshold 1 0 1
9 HITAUA Aerosol optical thickness larger than threshold 1 0 1
10 EPSOUT Atmospheric correction warning: Epsilon out-of-bounds 0 0 0
11 OVERITER Maximum iterations reached for NIR correction 0 0 0
12 NEGNLW Negative nLw in one or more bands 1 0 1
13 HIGHWS Surface wind speed higher than threshold 0 0 0
14 TURBIDW Turbid Case 2 water 0 0 0
15 reserved Spare 0 0 0

* Bits masked by statistical processing are indicated by 1.

Bit ver2 Description NWLR_380-670_L3_mask* PAR_L3_mask* TAUA_670,865_L3_mask*
0 DATAMISS No observation data in one or more band[s] 1 1 1
1 LAND Land pixel 1 0 1
2 ATMFAIL Atmospheric correction failure 1 0 1
3 CLDICE Apparent cloud/ice (high reflectance) 1 0 1
4 CLDAFFCTD Cloud-affected (near-cloud or thin/sub-pixel cloud) 1 0 1
5 STRAYLIGHT Stray light anticipated (ref. L1B stray light flags & image) 0 0 0
6 HIGLINT High sun glint predicted (atmospheric corr. abandoned) 1 0 1
7 MODGLINT Moderate sun glint predicted (correction applied) 1 0 1
8 HISOLZ Solar zenith larger than threshold 1 0 1
9 HITAUA Aerosol optical thickness larger than threshold 0 0 0
10 GAMMA-OUT Atmospheric correction warning: Gamma out-of-bounds 0 0 0
11 OVERITER Maximum iterations reached for NIR correction 0 0 0
12 NEGNLW Negative nLw in one or more bands 0 0 0
13 HIGHWS Surface wind speed higher than threshold 0 0 0
14 ATM-METHOD NIR atmospheric correction:0, SWIR atmospheric correction:1 0 0 0
15 reserved Spare 0 0 0

* Bits masked by statistical processing are indicated by 1.

*Download:QA_flag(Ver1) Sample Image
*Download:QA_flag(Ver2) Sample Image

Attribute information

Ver.1 Ver.2

Data_name Attribute Remarks
Attribute of Image_data
Attribute of Image_data Number_of_lines 5980 Variable
Number_of_pixels 5000 Variable
Image_projection L1B reference grid
Grid_interval 250 250m or 1km
Grid_interval_unit meter
Line_tai93
Line_tai93
64-bit floating-point
Data_description TAI93 at each line
Unit second
Error_value -1
Maximum_valid_value 999999999
Minimum_valid_value 0
Dim0 L1B-lines
NWLR_380
NWLR_380
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.00000114454
Rrs_offset -0.00915631
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 380.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 380.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 380
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1129.58
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_412
NWLR_412
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000730075
Rrs_offset -0.0058406
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 412.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 412.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 412
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1770.84
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_443
NWLR_443
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000658477
Rrs_offset -0.00526782
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 443.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 443.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 443
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1963.39
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_490
NWLR_490
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000644842
Rrs_offset -0.00515873
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 490.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 490.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 490
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 2004.9
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_530
NWLR_530
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000675325
Rrs_offset -0.0054026
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 530.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 530.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 530
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1914.4
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_565
NWLR_565
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000695552
Rrs_offset -0.00556441
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 565.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 565.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 565
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1858.73
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_670
NWLR_670
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.00000083191
Rrs_offset -0.00665528
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 673.5 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 673.5 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 673.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1554.07
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
PAR
PAR
16-bit unsigned integer
Data_description Photosynthetically Available Radiation
Unit Ein/m^2/day
Slope 0.005
Offset 0
Minimum_valid_DN 0
Maximum_valid_DN 65534
Error_DN 65535
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Mask_for_statistics 1 詳細: QA_flag情報(~L3_mask)
TAUA_670
TAUA_670
16-bit unsigned integer
Offset 0
Slope 0.0001
Data_description Aerosol Optical Thickness(TauA) at 673.5 = DN * Slope + Offset
Unit NA
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 673.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
Dim0 Line grids
Dim1 Pixel grids
TAUA_865
TAUA_865
16-bit unsigned integer
Offset 0
Slope 0.0001
Data_description Aerosol Optical Thickness(TauA) at 868.5 = DN * Slope + Offset
Unit NA
Mask_for_statistics 5087 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 868.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
Dim0 Line grids
Dim1 Pixel grids
Ver2 Attribute Remarks
Attribute of Image_data
Attribute of Image_data Number_of_lines 5980 Variable
Number_of_pixels 5000 Variable
Image_projection L1B reference grid
Grid_interval 250 250m or 1km
Grid_interval_unit meter
Line_tai93
Line_tai93
64-bit floating-point
Data_description TAI93 at each line
Unit second
Error_value -1
Maximum_valid_value 999999999
Minimum_valid_value 0
Dim0 L1B-lines
NWLR_380
NWLR_380
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.00000114454
Rrs_offset -0.00915631
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 380.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 380.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 380
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1129.58
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_412
NWLR_412
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000730075
Rrs_offset -0.0058406
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 412.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 412.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 412
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1770.84
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_443
NWLR_443
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000658477
Rrs_offset -0.00526782
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 443.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 443.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 443
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 1963.39
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_490
NWLR_490
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000644842
Rrs_offset -0.00515873
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 490.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 490.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 490
Center_wavelength_unit nm
Band_width 10
Band_width_unit nm
F0 2004.9
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_530
NWLR_530
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000675325
Rrs_offset -0.0054026
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 530.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 530.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 530
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1914.4
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_565
NWLR_565
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.000000695552
Rrs_offset -0.00556441
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 565.0 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 565.0 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 565
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1858.73
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
NWLR_670
NWLR_670
16-bit unsigned integer
Offset -10
Slope 0.00125
Rrs_slope 0.00000083191
Rrs_offset -0.00665528
Rrs_unit sr^-1
Data_description Normalized Water Leaving Radiance(NWLR) at 673.5 nm [W/m^2/sr/um] = DN * Slope + Offset; Remote Sensing Reflectance(Rrs) at 673.5 nm [sr^-1] = DN * Rrs_slope + Rrs_offset
Unit W/m^2/sr/um
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 673.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
F0 1554.07
F0_unit W/m^2/um
Dim0 Line grids
Dim1 Pixel grids
PAR
PAR
16-bit unsigned integer
Data_description Photosynthetically Available Radiation
Unit Ein/m^2/day
Slope 0.005
Offset 0
Minimum_valid_DN 0
Maximum_valid_DN 65534
Error_DN 65535
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Mask_for_statistics 1 詳細: QA_flag情報(~L3_mask)
TAUA_670
TAUA_670
16-bit unsigned integer
Offset 0
Slope 0.0001
Data_description Aerosol Optical Thickness(TauA) at 673.5 = DN * Slope + Offset
Unit NA
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 673.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
Dim0 Line grids
Dim1 Pixel grids
TAUA_865
TAUA_865
16-bit unsigned integer
Offset 0
Slope 0.0001
Data_description Aerosol Optical Thickness(TauA) at 868.5 = DN * Slope + Offset
Unit NA
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Spatial_resolution 250 250m または 1km
Spatial_resolution_unit meter
Error_DN 65535
Maximum_valid_DN 65534
Minimum_valid_DN 0
Center_wavelength 868.5
Center_wavelength_unit nm
Band_width 20
Band_width_unit nm
Dim0 Line grids
Dim1 Pixel grids

How to use

  • Physical quantity=DN*slope+offset