Aerosol by near ultra violet (ARNP)

Introduction

ARNP Define Optical thickness, Angstrom exponent, and classification of aerosol over land and ocean.
Unit none
ATBD Ver.1 (Jul. 2018)
Ver.2 (May. 2020)

Update contents of Ver2

  • ・Added auxiliary data (Himawari aerosol assimilation model data)

Stored Physical quantity

Ver1,2 Description
ARAE_land Angstrom Exponent over Land at 500 nm and 380 nm
ARAE_ocean Angstrom Exponent over Ocean at 500 nm and 865 nm
AROT_land Aerosol Optical Thickness over Land at 500 nm
AROT_ocean Aerosol Optical Thickness over Ocean at 500 nm
ARSSA_land Single Scattering Albedo over Land at 380 nm
QA_flag

QA_flag information

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

Bit ver1,2 Description ARAE_land_L3_mask* ARAE_ocean_L3_mask* AROT_land_L3_mask* AROT_ocean_L3_mask* ARSSA_land_L3_mask*
0 Data Availability 0=Available, 1=Not Available 0 0 0 0 0
1 Land / Water Flag 0=Water, 1=Land 0 0 0 0 0
2 Coastal Flag 0=No, 1=Yes 0 0 0 0 0
3 Cloud Flag 0=Clear, 1=Cloudy 0 0 0 0 0
4 Aerosol Optical Thickness Confidence Flag 00=Very Good; 01=Good, 10=Marginal, 11=No Confidence or Fill 0 0 0 0 0
5 Aerosol Optical Thickness Confidence Flag 0 0 1 1 0
6 Angstrom Exponent Confidence Flag 00=Very Good; 01=Good, 10=Marginal, 11=No Confidence or Fill 0 0 0 0 0
7 Angstrom Exponent Confidence Flag 1 1 0 0 0
8 Aerosol Single Scattering Albedo Confidence Flag 00=Very Good; 01=Good, 10=Marginal, 11=No Confidence or Fill 0 0 0 0 0
9 Aerosol Single Scattering Albedo Confidence Flag 0 0 0 0 1
10 Sunglint Flag 0=No, 1=Yes 0 0 0 0 0
11 Stray-Light Flag 0=No, 1=Yes 0 0 0 0 0
12 Cloud Shadow Possibility Flag 0=No, 1=Yes 0 0 0 0 0
13 Uncertain Surface Reflectance Flag (Turbid Water, Snow/Ice Covered Surface or Rtoa_obs < Rtoa_Rayleigh) 0=No, 1=Yes 0 0 0 0 0
14 Spare 0 0 0 0 0
15 Spare 0 0 0 0 0

* Bits masked by statistical processing are indicated by 1.

*Download:QA_flag(Ver1,2) Sample Image

Attribute information

Ver.1 Ver.2

Ver1 Attribute Remarks
Attribute of Image_data
Attribute of Image_data Grid_interval 0.00833333 1km: 0.00833333
Grid_interval_unit deg
Image_projection EQA (sinusoidal equal area) projection from 0-deg longitude
Lower_left_latitude 40 Variable
Lower_left_longitude 130.541
Lower_right_latitude 40
Lower_right_longitude 143.595
Number_of_lines 1200 1km: 1200
Number_of_pixels 1200
Upper_left_latitude 50 Variable
Upper_left_longitude 155.572
Upper_right_latitude 50
Upper_right_longitude 171.13
ARAE_land
ARAE_land
16-bit unsigned integer
Data_description Angstrom Exponent over Land at 500 nm and 380 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 2500
Minimum_valid_DN 0
Offset -0.5
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 128 Detail: QA_flag_information(~L3_mask)
ARAE_ocean
ARAE_ocean
16-bit unsigned integer
Data_description Angstrom Exponent over Ocean at 500 nm and 865 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 2500
Minimum_valid_DN 0
Offset -0.5
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 128 Detail: QA_flag_information(~L3_mask)
AROT_land
AROT_land
16-bit unsigned integer
Data_description Aerosol Optical Thickness over Land at 500 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 5000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 32 Detail: QA_flag_information(~L3_mask)
AROT_ocean
AROT_ocean
16-bit unsigned integer
Data_description Aerosol Optical Thickness over Ocean at 500 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 5000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 32 Detail: QA_flag_information(~L3_mask)
ARSSA_land
ARSSA_land
16-bit unsigned integer
Data_description Single Scattering Albedo over Land at 380 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 1000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 512 Detail: QA_flag_information(~L3_mask)
QA_flag
QA_flag
16-bit unsigned integer
Data_description (Please refer to the QA_flag information)
Error_DN 0
Maximum_valid_DN 65535
Minimum_valid_DN 0
Offset 0
Slope 1
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Unit = Dimensionless Dimensionless
Ver2 Attribute Remarks
Attribute of Image_data
Attribute of Image_data Grid_interval 0.00833333 1km: 0.00833333
Grid_interval_unit deg
Image_projection EQA (sinusoidal equal area) projection from 0-deg longitude
Lower_left_latitude 40 Variable
Lower_left_longitude 130.541
Lower_right_latitude 40
Lower_right_longitude 143.595
Number_of_lines 1200 1km: 1200
Number_of_pixels 1200
Upper_left_latitude 50 Variable
Upper_left_longitude 155.572
Upper_right_latitude 50
Upper_right_longitude 171.13
ARAE_land
ARAE_land
16-bit unsigned integer
Data_description Angstrom Exponent over Land at 500 nm and 380 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 2500
Minimum_valid_DN 0
Offset -0.5
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 128 Detail: QA_flag_information(~L3_mask)
ARAE_ocean
ARAE_ocean
16-bit unsigned integer
Data_description Angstrom Exponent over Ocean at 500 nm and 865 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 2500
Minimum_valid_DN 0
Offset -0.5
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 128 Detail: QA_flag_information(~L3_mask)
AROT_land
AROT_land
16-bit unsigned integer
Data_description Aerosol Optical Thickness over Land at 500 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 5000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 32 Detail: QA_flag_information(~L3_mask)
AROT_ocean
AROT_ocean
16-bit unsigned integer
Data_description Aerosol Optical Thickness over Ocean at 500 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 5000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 32 Detail: QA_flag_information(~L3_mask)
ARSSA_land
ARSSA_land
16-bit unsigned integer
Data_description Single Scattering Albedo over Land at 380 nm | VAL=DN*Slope+Offset
Error_DN 65535
Maximum_valid_DN 1000
Minimum_valid_DN 0
Offset 0
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Slope 0.001
Unit Dimensionless
Mask_for_statistics 512 Detail: QA_flag_information(~L3_mask)
QA_flag
QA_flag
16-bit unsigned integer
A_priori_of_retrieval Model: used MASINGER model data
Constant: used constant value
Data_description (Please refer to the QA_flag information)
Error_DN 0
Maximum_valid_DN 65535
Minimum_valid_DN 0
Offset 0
Slope 1
Spatial_resolution 0.00833333 1km: 0.00833333
Spatial_resolution_unit degree
Unit = Dimensionless Dimensionless

How to use

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