Data

IMOS - Satellite Remote Sensing - MODIS - 01 day - Diffuse attenuation coefficient (k490)

Integrated Marine Observing System
Integrated Marine Observing System (IMOS)
Viewed: [[ro.stat.viewed]] Cited: [[ro.stat.cited]] Accessed: [[ro.stat.accessed]]
ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rfr_id=info%3Asid%2FANDS&rft_id=https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/a8632154-b8e5-493d-acd4-e458fae3ae26&rft.title=IMOS - Satellite Remote Sensing - MODIS - 01 day - Diffuse attenuation coefficient (k490)&rft.identifier=https://catalogue-imos.aodn.org.au:443/geonetwork/srv/api/records/a8632154-b8e5-493d-acd4-e458fae3ae26&rft.description=The Aqua satellite platform carries a MODIS sensor that observes sunlight reflected from within the ocean surface layer at multiple wavelengths. These multi-spectral measurements are used to infer the diffuse attenuation coefficient (Kd) at 490nm wavelength which provides information on how light is attenuated in the water column. It is defined as the scaling length of the exponential decrease of the downwelling irradiance and has units (m^-1). The MODIS K490 product estimates Kd at 490nm wavelength, using a semi-empirical model based on the ratio of water leaving radiances at 490nm and 555nm. The algorithm is described at https://oceancolor.gsfc.nasa.gov/atbd/kd/.Production of contemporary MODIS data ceased at 2024/12/26. Users requiring similar Ocean Colour Radiometry data beyond 2024 should consider the VIIRS instruments on the SNPP and NOAA20+ series of satellites, also provided by IMOS.Statement: The radiometric sensitivity of the MODIS sensor is evolving continuously during its mission and is monitored regularly by NASA. The SeaDAS software uses tables of calibration coefficients that are updated periodically. From time to time upgrades to the algorithms and/or the format of the calibration tables are required, in which case a new version of SeaDAS is released. These data were updated on 1 September 2020 to use processing in SeaDAS v7.5 and between 2002/07/04 and 2022/06/30 are consistent with the R2018.0 reprocessing (https://oceancolor.gsfc.nasa.gov/reprocessing/r2018/aqua/). Data between 2022/07/01-2023/01/31 and then from 2023/02/01 onwards, have been processed with two more recent releases of SeaDAS and are yet to be fully verified for consistency with NASA’s most recent processing(s). Production of contemporary MODIS data ceased at 2024/12/26. Users requiring similar Ocean Colour Radiometry data beyond 2024 should consider the VIIRS instruments on the SNPP and NOAA20+ series of satellites, also provided by IMOS. It is anticipated that during 2025 IMOS will complete a reprocessing of the entire MODIS archive from 2002/07/04 – 2024/12/26 that will be consistent throughout with the latest recommended NASA processing version. The data are produced by combining the near real time (nrt) data stream from all the available direct broadcast reception stations in Australia with delayed-mode data from NASA in the US. The data have been remapped from satellite projection into a geographic (Latitude/Longitude axes) projection (0.01 degree sampling) and are presented as a sequence of daily mosaics covering the region (80 &rft.creator=Integrated Marine Observing System (IMOS) &rft.date=2014&rft.coverage=westlimit=80.00; southlimit=-60.00; eastlimit=179.90; northlimit=10.00&rft.coverage=westlimit=80.00; southlimit=-60.00; eastlimit=179.90; northlimit=10.00&rft_rights=Creative Commons Attribution 4.0 International License http://creativecommons.org/licenses/by/4.0/&rft_rights=The citation in a list of references is: IMOS [year-of-data-download], [Title], [data-access-URL], accessed [date-of-access].&rft_rights=Any users of IMOS data are required to clearly acknowledge the source of the material in the format: Data was sourced from Australia’s Integrated Marine Observing System (IMOS) – IMOS is enabled by the National Collaborative Research Infrastructure strategy (NCRIS). If relevant, also credit other organisations involved in collection of this particular datastream (as listed in 'credit' in the metadata record).&rft_rights=Data, products and services from IMOS are provided as is without any warranty as to fitness for a particular purpose.&rft_subject=oceans&rft_subject=OCEAN COLOR&rft_subject=EARTH SCIENCE&rft_subject=OCEANS&rft_subject=OCEAN OPTICS&rft_subject=Aqua&rft_subject=Light extinction coefficient (490nm wavelength) in the water body&rft_subject=ocean colour radiometers&rft_subject=Ocean Colour Sub-Facility, Integrated Marine Observing System (IMOS)&rft_subject=Countries | New Caledonia&rft_subject=Regional Seas | Java Sea&rft_subject=Countries | Indonesia&rft_subject=Regional Seas | Banda Sea&rft_subject=Countries | Fiji&rft_subject=States, Territories (Australia) | New South Wales&rft_subject=Regional Seas | Tasman Sea&rft_subject=States, Territories (Australia) | Northern Territory&rft_subject=Regional Seas | Coral Sea&rft_subject=Marine Features (Australia) | Great Australian Bight, SA/WA&rft_subject=States, Territories (Australia) | Queensland&rft_subject=Countries | New Zealand&rft_subject=Regional Seas | Arafura Sea&rft_subject=Regional Seas | Solomon Sea&rft_subject=Countries | Philippines&rft_subject=States, Territories (Australia) | Western Australia&rft_subject=Regional Seas | Philippine Sea&rft_subject=Marine Features (Australia) | Bass Strait, TAS/VIC&rft_subject=Countries | Timor-Leste&rft_subject=Countries | Papua New Guinea&rft_subject=Regional Seas | Celebes Sea&rft_subject=Regional Seas | Timor Sea&rft_subject=Countries | Malaysia&rft_subject=Countries | Australia&rft_subject=Global / Oceans | Indian Ocean&rft_subject=Global / Oceans | Southern Ocean&rft_subject=Global / Oceans | Pacific Ocean&rft_subject=Countries | Vanuatu&rft_subject=States, Territories (Australia) | Tasmania&rft_subject=States, Territories (Australia) | Victoria&rft_subject=States, Territories (Australia) | South Australia&rft.type=dataset&rft.language=English Access the data
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Licence & Rights:

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Creative Commons Attribution 4.0 International License
http://creativecommons.org/licenses/by/4.0/

The citation in a list of references is: "IMOS [year-of-data-download], [Title], [data-access-URL], accessed [date-of-access]."

Any users of IMOS data are required to clearly acknowledge the source of the material in the format: "Data was sourced from Australia’s Integrated Marine Observing System (IMOS) – IMOS is enabled by the National Collaborative Research Infrastructure strategy (NCRIS)." If relevant, also credit other organisations involved in collection of this particular datastream (as listed in 'credit' in the metadata record).

Data, products and services from IMOS are provided "as is" without any warranty as to fitness for a particular purpose.

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Full description

The Aqua satellite platform carries a MODIS sensor that observes sunlight reflected from within the ocean surface layer at multiple wavelengths. These multi-spectral measurements are used to infer the diffuse attenuation coefficient (Kd) at 490nm wavelength which provides information on how light is attenuated in the water column. It is defined as the scaling length of the exponential decrease of the downwelling irradiance and has units (m^-1). The MODIS K490 product estimates Kd at 490nm wavelength, using a semi-empirical model based on the ratio of water leaving radiances at 490nm and 555nm. The algorithm is described at https://oceancolor.gsfc.nasa.gov/atbd/kd/.

Production of contemporary MODIS data ceased at 2024/12/26. Users requiring similar Ocean Colour Radiometry data beyond 2024 should consider the VIIRS instruments on the SNPP and NOAA20+ series of satellites, also provided by IMOS.

Lineage

Statement: The radiometric sensitivity of the MODIS sensor is evolving continuously during its mission and is monitored regularly by NASA. The SeaDAS software uses tables of calibration coefficients that are updated periodically. From time to time upgrades to the algorithms and/or the format of the calibration tables are required, in which case a new version of SeaDAS is released. These data were updated on 1 September 2020 to use processing in SeaDAS v7.5 and between 2002/07/04 and 2022/06/30 are consistent with the R2018.0 reprocessing (https://oceancolor.gsfc.nasa.gov/reprocessing/r2018/aqua/). Data between 2022/07/01-2023/01/31 and then from 2023/02/01 onwards, have been processed with two more recent releases of SeaDAS and are yet to be fully verified for consistency with NASA’s most recent processing(s). Production of contemporary MODIS data ceased at 2024/12/26. Users requiring similar Ocean Colour Radiometry data beyond 2024 should consider the VIIRS instruments on the SNPP and NOAA20+ series of satellites, also provided by IMOS. It is anticipated that during 2025 IMOS will complete a reprocessing of the entire MODIS archive from 2002/07/04 – 2024/12/26 that will be consistent throughout with the latest recommended NASA processing version. The data are produced by combining the near real time (nrt) data stream from all the available direct broadcast reception stations in Australia with delayed-mode data from NASA in the US. The data have been remapped from satellite projection into a geographic (Latitude/Longitude axes) projection (0.01 degree sampling) and are presented as a sequence of daily mosaics covering the region (80 <= Longitude <= 180, -60 <= Latitude <= +10) formatted as CF-compliant netCDF files. It should be noted that the data are not processed until the definitive spacecraft ephemeris becomes available, usually 12-24 hours after the overpass. This means that the geolocation should be of a uniformly high standard. The filenames are of the form A.P1D.TZ...nc, where 'A" denotes the Aqua/MODIS sensor, 'P1D' is a period of 1 day, 'TZ' is the UTC date+time of the centre of the compositing interval, '' is the area covered (normally 'aust' for Australasia). '' is the name of the data product and 'nc' denotes a netCDF format file. Files are written in netCDF4 format with compression.

Notes

Credit
Australia’s Integrated Marine Observing System (IMOS) is enabled by the National Collaborative Research Infrastructure Strategy (NCRIS). It is operated by a consortium of institutions as an unincorporated joint venture, with the University of Tasmania as Lead Agent.
Credit
CSIRO Oceans and Atmosphere

Created: 02 06 2014

Data time period: 04 07 2002 to 2024-12-26

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179.9,10 179.9,-60 80,-60 80,10 179.9,10

129.95,-25

text: westlimit=80.00; southlimit=-60.00; eastlimit=179.90; northlimit=10.00

Subjects
Aqua | Countries | Australia | Countries | Fiji | Countries | Indonesia | Countries | Malaysia | Countries | New Caledonia | Countries | New Zealand | Countries | Papua New Guinea | Countries | Philippines | Countries | Timor-Leste | Countries | Vanuatu | EARTH SCIENCE | Global / Oceans | Indian Ocean | Global / Oceans | Pacific Ocean | Global / Oceans | Southern Ocean | Light extinction coefficient (490nm wavelength) in the water body | Marine Features (Australia) | Bass Strait, TAS/VIC | Marine Features (Australia) | Great Australian Bight, SA/WA | Ocean Color | OCEAN OPTICS | OCEANS | Ocean Colour Sub-Facility, Integrated Marine Observing System (IMOS) | Regional Seas | Arafura Sea | Regional Seas | Banda Sea | Regional Seas | Celebes Sea | Regional Seas | Coral Sea | Regional Seas | Java Sea | Regional Seas | Philippine Sea | Regional Seas | Solomon Sea | Regional Seas | Tasman Sea | Regional Seas | Timor Sea | States, Territories (Australia) | New South Wales | States, Territories (Australia) | Northern Territory | States, Territories (Australia) | Queensland | States, Territories (Australia) | South Australia | States, Territories (Australia) | Tasmania | States, Territories (Australia) | Victoria | States, Territories (Australia) | Western Australia | ocean colour radiometers | oceans |

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Other Information
(Link to OPENDAP server)

uri : http://thredds.aodn.org.au/thredds/catalog/IMOS/SRS/OC/gridded/aqua/P1D/catalog.html

(Satellite Remote Sensing page on IMOS website)

uri : http://imos.org.au/srs.html

(View and download data though the AODN Portal)

uri : https://portal.aodn.org.au/search?uuid=a8632154-b8e5-493d-acd4-e458fae3ae26

SRS - K490 - WMS layer (srs_oc_aqua_K_490_url/K_490)

uri : http://geoserver-123.aodn.org.au/geoserver/ncwms

The GoGoDuck subsets and aggregates gridded data. Data is returned as a NetCDF file. (srs_oc_aqua_K_490_url)

uri : https://processes.aodn.org.au/wps

(GoGoDuck help documentation)

uri : https://help.aodn.org.au/web-services/gogoduck-aggregator/

(Access To AWS Open Data Program registry for the Cloud Optimised version of this dataset)

uri : https://registry.opendata.aws/aodn_satellite_diffuse_attenuation_coefficent_1day_aqua/

(Access to Jupyter notebook to query Cloud Optimised converted dataset])

uri : https://nbviewer.org/github/aodn/aodn_cloud_optimised/blob/main/notebooks/satellite_diffuse_attenuation_coefficent_1day_aqua.ipynb

global : 8209bf83-0c3c-4fbe-9f36-41f7a5ee9913

Identifiers
  • global : a8632154-b8e5-493d-acd4-e458fae3ae26