In-water properties (IWPR)

Introduction

CHLA Define Define: Concentration of the green pigment in phytoplankton in sea surface layer.
Unit mg/m3
ATBD(Update date) Ver1(Oct.2018)
Ver2(Jan.2020)
TSM Define Dry weight of suspended matter in a unit volume of surface water which is the sum of organics such as phytoplankton and inorganics such as soil.
Uni g/m3
ATBD(Update date) Ver1(Oct.2011)
Ver.2 (May. 2020)
CDOM Define Light absoption coefficient of organics dissolved in surface water at 412nm.
Uni 1/m
ATBD(Update date) Ver1(Mar.2019)
Ver1_IOP(Mar.2019)
Ver2(Mar.2020)
Ver2_IOP(Mar.2019)

Update contents of Ver2

  • ・Improved the algorithm of CDOM and TSM
  • ・Modified QA flag

Stored Physical quantity

Ver1,2 Description
CDOM Colored dissolved organic matter
CHLA Chllorophyll-a concentration
Line_tai93 TAI93 at each line
QA_flag
TSM Total suspended matter

QA_flag information

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

Bit ver1 Description CDOM_L3_mask* CHLA_L3_mask* TSM_L3_mask*
0 DATAMISS No observation data in one or more band[s] 1 1 1
1 LAND Land pixel 1 1 1
2 ATMFAIL Atmospheric correction failure 1 1 1
3 CLDICE Apparent cloud/ice (high reflectance) 1 1 1
4 CLDAFFCTD Cloud-affected (near-cloud or thin/sub-pixel cloud) 1 1 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 1 1
7 MODGLINT Moderate glint predicted (correction applied) 1 1 1
8 HISOLZ Solar zenith larger than threshold 1 1 1
9 HITAUA Aerosol optical thickness larger than threshold 1 1 1
10 NEGNLW Negative nLw in one or more bands 1 1 1
11 TURBIDW Turbid Case 2 water 0 0 0
12 SHALLOW Shallow water than threshold 0 0 0
13 ITERFAILCDOM Iteration failure for CDOM algorithm 1 0 0
14 CHLWARN Chlorophyll a estimate out of range 0 1 0
15 reserved SPARE - - -

* Bits masked by statistical processing are indicated by 1.

Bit ver2 Description CDOM_L3_mask* CHLA_L3_mask* TSM_L3_mask*
0 DATAMISS No observation data in one or more band[s] 1 1 1
1 LAND Land pixel 1 1 1
2 ATMFAIL Atmospheric correction failure 1 1 1
3 CLDICE Apparent cloud/ice (high reflectance) 1 1 1
4 CLDAFFCTD Cloud-affected (near-cloud or thin/sub-pixel cloud) 1 1 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 1 1
7 MODGLINT Moderate glint predicted (correction applied) 1 1 1
8 HISOLZ Solar zenith larger than threshold 1 1 1
9 HITAUA Aerosol optical thickness larger than threshold 0 0 0
10 NEGNLW Negative nLw in one or more bands 0 0 0
11 ATM-METHOD NIR atmospheric correction:0, SWIR atmospheric correction:1 0 0 0
12 SHALLOW Shallow water than threshold 0 0 0
13 ITERFAILCDOM Iteration failure for CDOM algorithm 0 0 0
14 CHLWARN Chlorophyll a estimate out of range 0 0 0
15 reserved SPARE - - -

* 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
CDOM
CDOM
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Data_description Colored dissolved organic matter (CDOM) at 412nm = DN * Slope + Offset [m^-1]
Unit m^-1
Mask_for_statistics 10207 Detail: QA_flag_information(~L3_mask)
Slope 0.0001
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534
CHLA
CHLA
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Data_description Chllorophyll-a concentration (CHLA) = DN * Slope + Offset [mg m^-3]
Unit mg m^-3
Mask_for_statistics 18399 Detail: QA_flag_information(~L3_mask)
Slope 0.0016
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534
Line_tai93
Line_tai93
64-bit floating-point
Unit second
Data_description TAI93 at each line
Error_value -1
Maximum_valid_value 999999999
Minimum_valid_value 0
Dim0 L1B-lines
TSM
TSM
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Data_description Total suspended matter
Unit Total suspended matter (TSM) = DN * Slope + Offset [g m^-3]
Mask_for_statistics 2015 Detail: QA_flag_information(~L3_mask)
Slope 0.001
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534
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
CDOM
CDOM
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Data_description Colored dissolved organic matter (CDOM) at 412nm = DN * Slope + Offset [m^-1]
Unit m^-1
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Slope 0.0001
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534
CHLA
CHLA
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Data_description Chllorophyll-a concentration (CHLA) = DN * Slope + Offset [mg m^-3]
Unit mg m^-3
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Slope 0.0016
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534
Line_tai93
Line_tai93
64-bit floating-point
Unit second
Data_description TAI93 at each line
Error_value -1
Maximum_valid_value 999999999
Minimum_valid_value 0
Dim0 L1B-lines
TSM
TSM
16-bit unsigned integer
Dim0 Line grids
Dim1 Pixel grids
Unit g m^-3
Data_description Total suspended matter (TSM) = DN * Slope + Offset [g m^-3]
Mask_for_statistics 479 Detail: QA_flag_information(~L3_mask)
Slope 0.001
Offset 0
Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 65534

How to use

  • ・Physical quantity=DN*slope + offset
  • ・Valid values are during Minimum_valid_DN~Maximum_valid_DN