DATASET

GMIS - MODIS-AQUA Monthly anomalies sea surface diffuse attenuation coefficient at 490nm (4km) in %

Collection: GMIS : Global Marine Information System 

Description

Water Transparency (Diffuse attenuation coefficient at 490nm, Kd490 in m^-1 at 4km resolution): The diffuse attenuation coefficient Kd490 measures the light penetration in the water column at the blue-green wavelengths (ca. 490 nm). It represents a good indicator of water transparency resulting from the combined action of absorption and backscattering by the water constituents, and the structure of the surrounding light field.

Contact

Email
jrc-emis (at) ec.europa.eu

Contributors

  • Frederic Melin

How to cite

Melin, Frederic (2013): GMIS - MODIS-AQUA Monthly anomalies sea surface diffuse attenuation coefficient at 490nm (4km) in %. European Commission, Joint Research Centre (JRC) [Dataset] PID: http://data.europa.eu/89h/fb305be1-b763-49f8-87c5-a45fdcd44ea5

Keywords

marine environment marine monitoring sea surface diffuse attenuation coefficient anomalies ocean color sea water protection satellite observations climate change coastal environment GIS digital format

Data access

GMIS - Download access (GMIS_A_ANO_K490)
URL 
  • Direct NetCDF download

Spatial coverage

Type Value
GML
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GEO
POLYGON((-180 90,180 90,180 -90,-180 -90,-180 90))
GEO
{"type":"Polygon","crs":{"type":"name","properties":{"name":"urn:ogc:def:crs:OGC:1.3:CRS84"}},"coordinates":[[[-180.0,90.0],[180.0,90.0],[180.0,-90.0],[-180.0,-90.0],[-180.0,90.0]]]}

Temporal coverage

From date To date
2002-07-01 2017-12-31

Lineage information

General information: Monthly anomalies sea surface diffuse attenuation coefficient at 490nm in m^-1 (log10 scalling) derived from the MODIS-AQUA sensor. Processing information: Kd(490) data is processed using SeaDAS 6.4 software and the standard algorithm for Kd(490) (Werdell 2005). Temporal characteristics: This dataset consists of standard Monthly anomalies sea surface Kd(490) maps at 9km resolution (L3 product). Description of observation methods/instruments: The remote sensing of 'Ocean Colour' represents a measure of the spectral variations in the light leaving the water surface, subsequently interpreted in terms of concentrations of optically-significant constituents in the water. The electromagnetic signal collected by the sensor on-board the satellite is largely determined by photons that have never reached the water surface, but have been backscattered within the atmosphere through multiple interactions between gas molecules and aerosols. After removing the atmospheric contribution, the water leaving radiance recorded at a given time by the satellite reflects the optical properties of the water which, in turn, mirrors a specific structure and biogeochemical composition of the marine waters. The satellite-derived reflectance at the air-sea interface is related to apparent optical properties of the water constituents including Kd(490). Quality/accuracy/calibration information: The algorithm is an empirical band-ratio formula, with retrieval standard error and r^2 (for log-transformed data) of 0.28 and 0.89, respectively, as calculated over the development in situ data set (Werdell 2005). References: Werdell, P.J. (2005). Ocean color K490 algorithm evaluation. http://oceancolor.gsfc.nasa.gov/REPROCESSING/SeaWiFS/R5.1/k490_update.html Other contextual information: The product is stored in NetCDF data and available for download.

Additional information

Published by
European Commission, Joint Research Centre
Created date
2021-04-23
Modified date
2020-11-23
Issued date
2013-08-29
Landing page
http://gmis.jrc.ec.europa.eu/ 
Language(s)
English
Data theme(s)
Environment
Update frequency
unknown
Identifier
http://data.europa.eu/89h/fb305be1-b763-49f8-87c5-a45fdcd44ea5
Popularity