Abstract
Corrected Reflectance (CREFL) values for the Full Disk (FLDK) observations of Himawari-AHI.
The Corrected Reflectance product aims to remove the Rayleigh-scattered atmospheric component from top-of-atmosphere radiances. The contribution of Rayleigh scattering to the AHI observations is calculated by interpolating radiative transfer parameters from a preconstructed set of lookup tables, which are specifically created for the Himawari-AHI instruments. A surface reflectance value for each pixel is calculated after the Rayleigh contribution is removed.
Provided for each VIS and NIR band at the native spatial resolution, including band 01 (0.47um), band 02 (0.51um), band 03 (0.64um), band 04 (0.86um), band 05 (1.61um) and band 06 (2.26um).
Further information can be found in the following paper.
Format
NetCDF4
Basepath, Filename Template and Data Access
On NCI (requires an NCI account and membership of the ra22 data collection)
Basepath: /g/data/ra22/satellite-products/<datastream>/obs/fldk/<dataset version>/<year>/<month>/<day>/<hour/minute>/
Filename Template: <year><month><day><hour><minute>00-P1S-ABOM_CREFL_B<band number>-PRJ_GEOS141_<spatial resolution>-<satellite>-AHI.nc
<datastream>: nrt or arc
<band number>: 01 ~ 06
<spatial resolution>: 2000, 1000 or 500 (band dependent)
<satellite>: HIMAWARI8 or HIMAWARI9
On THREDDS (publicly available, no NCI account required)
Bureau of Meteorology - Satellite Observations (ra22) THREDDS
Basepath: satellite-products/<datastream>/obs/fldk/<dataset version>/<year>/<month>/<day>/<hour/minute>/
Filename Template: <year><month><day><hour><minute>00-P1S-ABOM_CREFL_B<band number>-PRJ_GEOS141_<spatial resolution>-<satellite>-AHI.nc
<datastream>: nrt or arc
<band number>: 01 ~ 06
<spatial resolution>: 2000, 1000 or 500 (band dependent)
<satellite>: HIMAWARI8 or HIMAWARI9
Version
Version 1.0: Initial release
License
Update Frequency
10 minutes (Near Realtime), 1 to 3 months (Archive)
Temporal extents (YYYY/MM/DD)
previous 3 months - present (Near Realtime), 2015/07/07 - present (Archive)
Spatial Extents
81N ~ 81S, 59E ~ 222E
Owner
Bureau of Meteorology
Contact
SI-Research-SS@bom.gov.au Satellite Science Team, Research, Bureau of Meteorology
Credit
Many thanks to the Japan Meteorological Agency (JMA) for providing Himawari-AHI data.
Metadata Example
netcdf \20210903232000-P1S-ABOM_CREFL_B01-PRJ_GEOS141_1000-HIMAWARI8-AHI {
dimensions:
time = 1 ;
y = 11000 ;
x = 11000 ;
variables:
double time(time) ;
time:coordinates = "time" ;
time:long_name = "time" ;
time:standard_name = "time" ;
time:units = "seconds since 1970-01-01 00:00:00" ;
time:calendar = "standard" ;
time:axis = "T" ;
double y(y) ;
y:coordinates = "y" ;
y:long_name = "projection_y_coordinate" ;
y:standard_name = "projection_y_coordinate" ;
y:units = "m" ;
y:axis = "Y" ;
double x(x) ;
x:coordinates = "x" ;
x:long_name = "projection_x_coordinate" ;
x:standard_name = "projection_x_coordinate" ;
x:units = "m" ;
x:axis = "X" ;
float geostationary ;
geostationary:proj_name = "GEOS141" ;
geostationary:sweep_angle_axis = "y" ;
geostationary:false_northing = 0 ;
geostationary:grid_mapping_name = "geostationary" ;
geostationary:false_easting = 0 ;
geostationary:satellite_height = 35785863. ;
geostationary:semi_major_axis = 6378137. ;
geostationary:semi_minor_axis = 6356752.3 ;
geostationary:perspective_point_height = 35785863. ;
geostationary:GeoTransform = -5500000., 1000., 0., 5500000., 0., -1000. ;
geostationary:longitude_of_projection_origin = 140.7 ;
geostationary:proj4 = "+proj=geos +lon_0=140.7 +h=35785863 +x_0=0 +y_0=0 +a=6378137 +b=6356752.3 +units=m +no_defs " ;
geostationary:spatial_ref = "PROJCS[\"unnamed\",GEOGCS[\"unnamed ellipse\",DATUM[\"unknown\",SPHEROID[\"unnamed\",6378137,298.2570248822731]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433]],PROJECTION[\"Geostationary_Satellite\"],PARAMETER[\"central_meridian\",140.7],PARAMETER[\"satellite_height\",35785863],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"Meter\",1]]" ;
double scan_line_time(y) ;
scan_line_time:long_name = "estimated scan line time" ;
scan_line_time:calendar = "standard" ;
scan_line_time:coordinates = "y" ;
scan_line_time:units = "seconds since 2021-09-03 23:20:00" ;
float channel_0001_corrected_reflectance(time, y, x) ;
channel_0001_corrected_reflectance:_FillValue = 1.e+20f ;
channel_0001_corrected_reflectance:algorithm_name = "channel_1_crefl" ;
channel_0001_corrected_reflectance:units = "1" ;
channel_0001_corrected_reflectance:valid_max = 5.f ;
channel_0001_corrected_reflectance:valid_min = 0.f ;
channel_0001_corrected_reflectance:coordinates = "time y x" ;
channel_0001_corrected_reflectance:grid_mapping = "geostationary" ;
channel_0001_corrected_reflectance:least_significant_digit = 3 ;
channel_0001_corrected_reflectance:central_wavelength = 4.7063e-07 ;
channel_0001_corrected_reflectance:comment = "corrected reflectance observed by the Advanced Himawari Imager at 0.47 um (Band 1)" ;
channel_0001_corrected_reflectance:long_name = "corrected reflectance for channel 1 at 0.47 um" ;
// global attributes:
:Conventions = "CF-1.6" ;
:Metadata_Conventions = "Unidata Dataset Discovery v1.0" ;
:acknowledgment = "See disclaimer" ;
:cdm_data_type = "grid" ;
:comment = "AGLS observations geometry product" ;
:contributor_name = "Commonwealth of Australia, Bureau of Meteorology, Science and Innovation, Science to Services, Weather and Environmental Prediction, Satellite Applications; Commonwealth of Australia, Bureau of Meteorology, Data and Digital, Observing Systems and Operations, Satellite Operations" ;
:contributor_role = "Development; Operations" ;
:creator_email = "sat_support@bom.gov.au" ;
:creator_name = "Commonwealth of Australia, Bureau of Meteorology, Data and Digital, Observing Systems and Operations, Satellite Operations" ;
:creator_url = "http://www.bom.gov.au/satellite/" ;
:disclaimer = "You have requested that the Bureau of Meteorology (\\\'Bureau\\\') provide you with an enhanced version of satellite data, images, information or other material (\\\'Material\\\').\\nYou understand that the Bureau does not operate the satellites and that the Material is subject to the uncertainties of imaging capabilities, adverse weather conditions and technical malfunction and may change without notice.\\nTo the maximum extent permitted by law, the Bureau: \\ndoes not make any representations or give any warranty that either the original Material or any Material enhanced by the Bureau is accurate, reliable, current, complete or fit for any purpose, and \\nexcludes all liability of the Bureau, and any suppliers of Material to the Bureau, for any loss, damage, cost, expense and any other consequences arising directly or indirectly from your use of the Material." ;
:geospatial_lat_resolution = 0.01f ;
:geospatial_lat_units = "degree_north" ;
:geospatial_lon_resolution = 0.01f ;
:geospatial_lon_units = "degree_east" ;
:geospatial_vertical_max = 0 ;
:geospatial_vertical_min = 0 ;
:geospatial_vertical_positive = "up" ;
:geospatial_vertical_resolution = 0 ;
:geospatial_vertical_units = "m" ;
:institution = "ABOM" ;
:instrument = "AHI" ;
:keywords = "EARTH SCIENCE" ;
:keywords_vocabulary = "NASA Global Change Master Directory (GCMD) Science Keywords" ;
:license = "See disclaimer" ;
:naming_authority = "au.gov.bom" ;
:processing_level = "L2" ;
:product_specification = "AGLS-CREFL_data-product-specification_rev01.00" ;
:product_suite = "CREFL_B01" ;
:project = "AGLS" ;
:publisher_email = "sat_support@bom.gov.au" ;
:publisher_name = "Commonwealth of Australia, Bureau of Meteorology, Data and Digital, Observing Systems and Operations, Satellite Operations" ;
:publisher_url = "http://www.bom.gov.au/satellite/" ;
:references = "Broomhall et al, 2019, Correcting Himawari-8 Advanced Himawari Imager data for the production of vivid true colour imagery. Journal of Atmospheric and Oceanic Technology" ;
:standard_name_vocabulary = "CF-1.6" ;
:summary = "AGLS observations product" ;
:time_coverage_duration = "P1S" ;
:time_coverage_resolution = "P1S" ;
:title = "AGLS observations product suite" ;
:wmo_instrument_name = "Advanced Himawari Imager" ;
:wmo_instrument_type = 297 ;
:wmo_satellite_series = 273 ;
:date_created = "20211020T093334Z" ;
:history = "saturnc" ;
:id = "ABOM_AGLS_CREFL_B01_P1S_GRID_v1.1" ;
:netCDF_version = "4.7.1 of Nov 5 2019 15:53:53 $" ;
:processing_version = "1.1" ;
:uuid = "e4799242-ac4f-451e-8e50-35918a53c534" ;
:geospatial_lat_max = 81.18433f ;
:geospatial_lat_min = -81.18433f ;
:geospatial_lon_max = 221.9616f ;
:geospatial_lon_min = 59.43843f ;
:platform = "Himawari-8" ;
:platform_launch_date = "20141007T051600Z" ;
:time_coverage_end = "20210903T232941Z" ;
:time_coverage_start = "20210903T232021Z" ;
:wmo_platform_name = "Himawari-8" ;
:wmo_satellite_number = 173 ;
}