Title

[ARCHIVE] Black Sea Reprocessed Surface Chlorophyll Concentration from Multi Satellite observations

Alternate title

OCEANCOLOUR_BS_CHL_L3_REP_OBSERVATIONS_009_071

Date (Creation)

2013-03-13

Edition

2.1

Edition date

2021-04-26

Citation identifier

a0501b52-1b8e-4fe3-a369-487563b6b23e

Abstract

'''This product has been archived'''

For operationnal and online products, please visit https://marine.copernicus.eu

'''Short description:'''

The Global Ocean Satellite monitoring and marine ecosystem study group (GOS) of the Italian National Research Council (CNR), in Rome, distributes surface chlorophyll concentration (mg m-3, 1 km resolution) derived from Rrs multi-sensor (MODIS-AQUA, NOAA20-VIIRS, NPP-VIIRS, Sentinel3A-OLCI) spectra at the state-of-the-art algorithms for multi-sensor merging. Single sensor Rrs fields are band-shifted, over the SeaWiFS native bands (using the QAAv6 model, Lee et al., 2002) and merged with a technique aimed at smoothing the differences among different sensors. Reprocessed (multi-year) products are consistent and homogeneous in terms of format, algorithms and processing software. The chlorophyll (Chl) product is obtained combining two different regional algorithms (BSAlg). The first is a band-ratio algorithm (B/R) (Zibordi et al., 2015) that computes Chl as a function of the slope of Rrs values at two wavelengths (490 and 555 nm) using a polynomial regression that captures the overall data trend. The second one is a Multilayer Perceptron (MLP) neural net based on Rrs values at three individual wavelengths (490, 510 and 555 nm) that features interpolation capabilities helpful to fit data nonlinearities. The merging scheme (Kajiyama et al., 2018) has been designed to use the B/R algorithm and the MLP neural net in waters exhibiting lower and higher optical complexity, respectively. The current day data temporal consistency is evaluated as Quality Index (QI):

QI=(CurrentDataPixel-ClimatologyDataPixel)/STDDataPixel

where QI is the difference between current data and the relevant climatological field as a signed multiple of climatological standard deviations (STDDataPixel).

'''Processing information:'''

Multi-sensor product is constituted by MODIS-AQUA, NOAA20-VIIRS, NPP-VIIRS and Sentinel3A-OLCI. For consistency with NASA L2 dataset, BRDF correction was applied to Sentinel3A-OLCI prior to band shifting and multi sensor merging. Single sensor NASA Level-2 data are destriped and then all Level-2 data are remapped at 1 km spatial resolution using cylindrical equirectangular projection. Afterwards, single sensor Rrs fields are band-shifted, over the SeaWiFS native bands (using the QAAv6 model, Lee et al., 2002) and merged with a technique aimed at smoothing the differences among different sensors. This technique is developed by The Global Ocean Satellite monitoring and marine ecosystem study group (GOS) of the Italian National Research Council (CNR, Rome). Then geophysical fields (i.e. chlorophyll and kd490) are estimated via state-of-the-art algorithms for better product quality. The entire data set is consistent and processed in one-shot mode (with an unique software version and identical configurations).

'''Description of observation methods/instruments:'''

Ocean colour technique exploits the emerging electromagnetic radiation from the sea surface in different wavelengths. The spectral variability of this signal defines the so-called ocean colour which is affected by the presence of phytoplankton.

'''Quality / Accuracy / Calibration information:'''

A detailed description of the calibration and validation activities performed over this product can be found on the CMEMS web portal.

'''Suitability, Expected type of users / uses:'''

This product is meant for use for educational purposes and for the managing of the marine safety, marine resources, marine and coastal environment and for climate and seasonal studies.

'''Dataset names:'''

*dataset-oc-bs-chl-multi-l3-chl_1km_daily-rep-v02

'''Files format:'''

*CF-1.4

*INSPIRE compliant

'''DOI (product) :'''

https://doi.org/10.48670/moi-00089

Credit

E.U. Copernicus Marine Service Information

Point of contact

Organisation name	Individual name	Electronic mail address	Role
OC-CNR-ROMA-IT	Emanuele BÖHM	gsdk@isac.cnr.it	Local service desk
OC-CNR-ROMA-IT	Rosalia SANTOLERI	rosalia.santoleri@cnr.it	Production center
OC-CNR-ROMA-IT	Gianluca VOLPE	gianluca.volpe@cnr.it	Product manager
OC-CNR-ROMA-IT	Simone COLELLA	simone.colella@cnr.it	Production Unit
OC-CNR-ROMA-IT	Javier CONCHA	gsdk@isac.cnr.it	Dissemination Unit

Maintenance and update frequency

Irregular

Other

/

Maintenance note

N/A

GEMET - INSPIRE themes, version 1.0

• Oceanographic geographical features

Discipline

• satellite-observation

Climate and Forecast Standard Names

• mass_concentration_of_chlorophyll_a_in_sea_water
• mass_concentration_of_picophytoplankton_expressed_as_chlorophyll_in_sea_water

Temporal scale

• multi-year

Area of benefit

• coastal-marine-environment
• marine-resources
• marine-safety
• weather-climate-and-seasonal-forecasting

Reference Geographical Areas

• black-sea

Processing level

• Level 3

Model assimilation

• Not Applicable

Use limitation

See Copernicus Marine Environment Monitoring Service Data commitments and licence at: http://marine.copernicus.eu/web/27-service-commitments-and-licence.php

Access constraints

Other restrictions

Use constraints

License

Other legal constraints

No limitations on public access

Aggregate Datasetindentifier

7bdc830b-6321-4ffb-ae76-8707256c6d03

Association Type

Cross reference

Initiative Type

Document

Aggregate Datasetindentifier

e0f8a482-d960-4c72-8976-8c63873ea4de

Association Type

Cross reference

Initiative Type

Document

Title

Kajiyama T., D. D’Alimonte, and G. Zibordi, “Algorithms merging for the determination of Chlorophyll-a concentration in the Black Sea,” IEEE Geoscience and Remote Sensing Letters, 2018. [Online]. Available: https://-www.doi.org/¬10.1109/¬LGRS.2018.2883539.

Date (Creation)

2019-05-08

Association Type

Cross reference

Initiative Type

Reference

Title

Zibordi, G., F. Mélin, J.-F. Berthon, and M. Talone (2015). In situ autonomous optical radiometry measurements for satellite ocean color validation in the Western Black Sea. Ocean Sci., 11, 275–286.

Date (Creation)

2019-05-08

Association Type

Cross reference

Initiative Type

Reference

Language

eng

Topic category

• Oceans

Description

bounding box

N

S

E

W

Begin date

1997-09-04

Supplemental Information

display priority: 11860

Reference system identifier

EPSG / WGS 84 / Plate Carree (EPSG:32662)

Number of dimensions

2

Dimension name

Row

Resolution

1  km

Dimension name

Column

Resolution

1  km

Cell geometry

Area

Transformation parameter availability

Distribution format

Name	Version
NetCDF-4	Classic model

Hierarchy level

Series

Statement

The myOcean products depends on other products for production or validation. The detailed list of dependencies is given in ISO19115's aggregationInfo (ISO19139 Xpath = "gmd:MD_Metadata/gmd:identificationInfo/gmd:aggregationInfo[./gmd:MD_AggregateInformation/gmd:initiativeType/gmd:DS_InitiativeTypeCode/@codeListValue='upstream-validation' or 'upstream-production']")

Attribute description

observation

Content type

Physical measurement

Descriptor

temporal resolution: daily mean

Descriptor

vertical level number: 1

Included with dataset

Feature types

Grid

Metadata

File identifier

a0501b52-1b8e-4fe3-a369-487563b6b23e

Metadata language

English

Character set

UTF8

Hierarchy level

Series

Hierarchy level name

Copernicus Marine Service product specification

Date stamp

2022-06-28T14:33:43.581Z

Metadata standard name

ISO 19139, MyOcean profile

Metadata standard version

0.2

Metadata author

Organisation name	Individual name	Electronic mail address	Role
CMEMS		servicedesk.cmems@mercator-ocean.eu	Local service desk