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Dataset Title:	Mediterranean Sea, Po River, DIVAnd 4D seasonal analysis of Water body chlorophyll-a 1978/2022 v2025 [observations]
Institution:	HCMR/HNODC (Dataset ID: oceanbrowser_opendap_41ea_d9dd_7814)
Information:	Summary \| License \| Metadata \| Background \| Data Access Form

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The Dataset Attribute Structure (.das) for this Dataset

Attributes {
  observations {
    Int32 actual_range 0, 129885;
    String long_name "Observations";
    String units "count";
  }
  obsdepth {
    Float64 colorBarMaximum 8000.0;
    Float64 colorBarMinimum -8000.0;
    String colorBarPalette "TopographyDepth";
    String long_name "depth below sea level";
    String positive "down";
    String standard_name "depth";
    String units "meters";
  }
  obslat {
    Float64 colorBarMaximum 90.0;
    Float64 colorBarMinimum -90.0;
    String long_name "latitude";
    String standard_name "latitude";
    String units "degrees_north";
  }
  obslon {
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String long_name "longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  obstime {
    String ioos_category "Time";
    String long_name "Time";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  NC_GLOBAL {
    String abstract 
"Water body chlorophyll-a - Seasonal Climatology for Po River for the period 1978-2022 on the domain: Lon E12.0-14.0deg., Lat N44.0-46.0deg.
Description of DIVA analysis: The computation was done with the DIVAnd (Data-Interpolating Variational Analysis in n dimensions), version 2.7.12, using GEBCO 30sec topography for the spatial connectivity of water masses.
The horizontal resolution of the produced DIVAnd maps grids is dx=dy=0.009 degrees (around 975m and 708m accordingly).
The vertical resolution is 14 depth levels: [0., 2., 4., 6., 8., 10., 15., 20., 25., 30., 40., 50., 60., 70.].
A relative correlation length used based on topography gradients and the horizontal correlation length varies from 25 km to 12.5 km. The vertical correlation length (in meters) is:  [4.,4.,4.,4.,4.,10.,10.,10.,10.,20.,20.,20.,20.,20.]. 
Duplicates check was performed using the following criteria for space and time: dlon=0.01deg., dlat=0.01deg., ddepth=0.01m, dtime=1min, dvalue=0.01.
The error variance (epsilon2) was set equal to 1. Data weight was reduced at shallow waters. Data weighting was applied with the following threshold values: lon=0.03, lat=0.03, depth=2.
An anamorphosis transformation was applied to the data (function DIVAnd.Anam.loglin) to avoid unrealistic negative values: threshold value=200.
The mean value was used as background analysis field.
Quality control of the observations was applied using the interpolated field (QCMETHOD=3). Residuals (differences between the observations and the analysis (interpolated linearly to the location of the observations) were calculated. Observations with residuals outside the minimum and maximum values of the 99% quantile were discarded from the analysis. 
Seasons definition: Winter=Jan-Mar, Spring=Apr-Jun, Summer=Jul-Sep, Autumn=Oct-Dec.
Originators of Italian data sets-List of contributors:
- Brunetti Fabio (OGS)
- Cardin Vanessa, Bensi Manuel doi:10.6092/36728450-4296-4e6a-967d-d5b6da55f306
- Cardin Vanessa, Bensi Manuel, Ursella Laura, Siena Giuseppe doi:10.6092/f8e6d18e-f877-4aa5-a983-a03b06ccb987
- Cataletto Bruno (OGS)
- Cinzia Comici Cinzia (OGS)
- Civitarese Giuseppe (OGS)
- DeVittor Cinzia (OGS)
- Giani Michele (OGS)
- Kovacevic Vedrana (OGS)
- Mosetti Renzo (OGS)
- Solidoro C.,Beran A.,Cataletto B.,Celussi M.,Cibic T.,Comici C.,Del Negro P.,De Vittor C.,Minocci M.,Monti M.,Fabbro C.,Falconi C.,Franzo A.,Libralato S.,Lipizer M.,Negussanti J.S.,Russel H.,Valli G., doi:10.6092/e5518899-b914-43b0-8139-023718aa63f5
- Celio Massimo (ARPA FVG)
- Malaguti Antonella (ENEA)
- Fonda Umani Serena (UNITS)
- Bignami Francesco (ISAC/CNR)
- Boldrini Alfredo (ISMAR/CNR)
- Marini Mauro (ISMAR/CNR)
- Miserocchi Stefano (ISMAR/CNR)
- Zaccone Renata (IAMC/CNR)
- Lavezza, R., Dubroca, L. F. C., Ludicone, D., Kress, N., Herut, B., Civitarese, G., Cruzado, A., LefÃ¨vre, D.,Souvermezoglou, E., Yilmaz, A., Tugrul, S., and Ribera d'Alcala, M.: Compilation of quality controlled nutrient profiles from the Mediterranean Sea, doi:10.1594/PANGAEA.771907, 2011.";
    String acknowledgement "Aggregated data products are generated by EMODnet Chemistry under the support of DG MARE Call for Tenders MARE/2008/03-lot3, MARE/2012/10-lot4, EASME/EMFF/2016/0006-lot4, EASME/2019/OP/0003-lot4, EASME/EMFF/2020/OP/0006-lot4, CINEA/2024/OP/0006-lot5";
    String area_keywords "Mediterranean Sea";
    String area_keywords_urn "SDN:C19::3_1";
    String Author_e_mail "Athanasia (Sissy) IONA <sissy@hnodc.hcmr.gr>";
    String bathymetry_source "The GEBCO Digital Atlas published by the British Oceanographic Data Centre on behalf of IOC and IHO, 2003. Resolution used for the analysis: 30 arc-second";
    String cdm_data_type "Grid";
    String comment "Seasonal climatology";
    String Conventions "CF-1.60, COARDS, ACDD-1.3";
    String creator_email "NODC.Webmaster@noaa.gov";
    String creator_name "HCMR/HNODC";
    String creator_type "institution";
    String creator_url "https://www.nodc.noaa.gov/";
    String data_access "https://emodnet.ec.europa.eu/geoviewer";
    String date "2025-09-15T22:50:09";
    String DIVA_code_doi "10.5281/zenodo.7016823";
    String DIVA_references "Barth, A.; Beckers, J.-M.; Troupin, C.; Alvera-AzcÃ¡rate, A. & Vandenbulcke, L. divand-1.0: n-dimensional variational data analysis for ocean observations Geoscientific Model Development, 2014, 7, 225-241. DOI: 10.5194/gmd-7-225-2014";
    String DIVAnd_source "https://github.com/gher-uliege/DIVAnd.jl";
    String DIVAnd_version "v2.7.12";
    String documentation "https://doi.org/10.13120/fa5c704a-a5ea-4f60-91b5-2bf6a7aded45";
    String doi "https://doi.org/10.13120/79ab43e3-5403-486f-b38c-c41494fe0722";
    String file_name "Water_body_chlorophyll-a.4Danl.nc";
    String history 
"Thu Nov  6 13:59:45 2025: ncks -7 -O -L 5 --baa=4 --ppc default=3 /media/ctroupin/T7 Shield/data/EMODnet-Chemistry/Eutrophication2024/Results/Coastal_areas-water_body/Mediterranean_Sea_-_Po_River/Water_body_chlorophyll-a.4Danl.nc /media/ctroupin/T7 Shield/data/EMODnet-Chemistry/Eutrophication2024/Results/Coastal_areas-water_body/Mediterranean_Sea_-_Po_River/Water_body_chlorophyll-a.4Danl.nc
2026-04-05T16:43:26Z http://opendap.oceanbrowser.net/thredds/dodsC/data/emodnet-projects/v2025/Coastal_areas-water_body/Mediterranean_Sea_-_Po_River/Water_body_chlorophyll-a.4Danl.nc
2026-04-05T16:43:26Z https://erddap.emodnet.eu/griddap/oceanbrowser_opendap_41ea_d9dd_7814.das";
    String id "DatasetScan/emodnet-projects/v2025/Coastal_areas-water_body/Mediterranean_Sea_-_Po_River/Water_body_chlorophyll-a.4Danl.nc";
    String infoUrl "https://doi.org/10.13120/fa5c704a-a5ea-4f60-91b5-2bf6a7aded45";
    String institution "HCMR/HNODC";
    String institution_urn "SDN:EDMO::269";
    String keywords "analysis, below, body, chla, chlorophyll, chlorophyll-a, cnr, control, council, data, depth, divand, hcmr, hnodc, latitude, level, longitude, mediterranean, national, obsdepth, observations, obslat, obslon, obstime, quality, research, river, sea, seasonal, seawater, time, v2025, water";
    String license 
"The data may be used and redistributed for free but is not intended
for legal use, since it may contain inaccuracies. Neither the data
Contributor, ERD, NOAA, nor the United States Government, nor any
of their employees or contractors, makes any warranty, express or
implied, including warranties of merchantability and fitness for a
particular purpose, or assumes any legal liability for the accuracy,
completeness, or usefulness, of this information.";
    String NCO "netCDF Operators version 5.2.1 (Homepage = http://nco.sf.net, Code = https://github.com/nco/nco, Citation = 10.1016/j.envsoft.2008.03.004)";
    String netcdf_long_name "Chlorophyll-a_particulate";
    String netcdf_standard_name "Water_body_chlorophyll-a";
    String netcdf_units "mg/m3";
    String parameter_keyword "Water body chlorophyll-a";
    String parameter_keyword_urn "SDN:P35::EPC00105";
    String product_code "Po River-Water body chlorophyll-a-v2025-ANA";
    String product_id "79ab43e3-5403-486f-b38c-c41494fe0722";
    String product_version "v2025";
    String project "EMODnet Chemistry phase 6";
    String search_keywords "Chlorophyll pigment concentrations in water bodies";
    String search_keywords_urn "SDN:P02::CPWC";
    String source "Observations from EMODnet Chemistry";
    String sourceUrl "http://opendap.oceanbrowser.net/thredds/dodsC/data/emodnet-projects/v2025/Coastal_areas-water_body/Mediterranean_Sea_-_Po_River/Water_body_chlorophyll-a.4Danl.nc";
    String standard_name_vocabulary "CF Standard Name Table v70";
    String summary 
"Mediterranean Sea - Po River - DIVAnd 4D seasonal analysis of Water body chlorophyll-a 1978/2022 v2025. Water body chlorophyll-a - Seasonal Climatology for Po River for the period 1978-2022 on the domain: Lon E12.0-14.0deg., Lat N44.0-46.0deg.
Description of DIVA analysis: The computation was done with the DIVAnd (Data-Interpolating Variational Analysis in n dimensions), version 2.7.12, using GEBCO 30sec topography for the spatial connectivity of water masses.
The horizontal resolution of the produced DIVAnd maps grids is dx=dy=0.009 degrees (around 975m and 708m accordingly).
The vertical resolution is 14 depth levels: [0., 2., 4., 6., 8., 10., 15., 20., 25., 30., 40., 50., 60., 70.].
A relative correlation length used based on topography gradients and the horizontal correlation length varies from 25 km to 12.5 km. The vertical correlation length (in meters) is:  [4.,4.,4.,4.,4.,10.,10.,10.,10.,20.,20.,20.,20.,20.]. 
Duplicates check was performed using the following criteria for space and time: dlon=0.01deg., dlat=0.01deg., ddepth=0.01m, dtime=1min, dvalue=0.01.
The error variance (epsilon2) was set equal to 1. Data weight was reduced at shallow waters. Data weighting was applied with the following threshold values: lon=0.03, lat=0.03, depth=2.
An anamorphosis transformation was applied to the data (function DIVAnd.Anam.loglin) to avoid unrealistic negative values: threshold value=200.
The mean value was used as background analysis field.
Quality control of the observations was applied using the interpolated field (QCMETHOD=3). Residuals (differences between the observations and the analysis (interpolated linearly to the location of the observations) were calculated. Observations with residuals outside the minimum and maximum values of the 99% quantile were discarded from the analysis. 
Seasons definition: Winter=Jan-Mar, Spring=Apr-Jun, Summer=Jul-Sep, Autumn=Oct-Dec.
Originators of Italian data sets-List of contributors:
- Brunetti Fabio (OGS)
- Cardin Vanessa, Bensi Manuel doi:10.6092/36728450-4296-4e6a-967d-d5b6da55f306
- Cardin Vanessa, Bensi Manuel, Ursella Laura, Siena Giuseppe doi:10.6092/f8e6d18e-f877-4aa5-a983-a03b06ccb987
- Cataletto Bruno (OGS)
- Cinzia Comici Cinzia (OGS)
- Civitarese Giuseppe (OGS)
- DeVittor Cinzia (OGS)
- Giani Michele (OGS)
- Kovacevic Vedrana (OGS)
- Mosetti Renzo (OGS)
- Solidoro C.,Beran A.,Cataletto B.,Celussi M.,Cibic T.,Comici C.,Del Negro P.,De Vittor C.,Minocci M.,Monti M.,Fabbro C.,Falconi C.,Franzo A.,Libralato S.,Lipizer M.,Negussanti J.S.,Russel H.,Valli G., doi:10.6092/e5518899-b914-43b0-8139-023718aa63f5
- Celio Massimo (ARPA FVG)
- Malaguti Antonella (ENEA)
- Fonda Umani Serena (UNITS)
- Bignami Francesco (ISAC/National Research Council (CNR))
- Boldrini Alfredo (ISMAR/CNR)
- Marini Mauro (ISMAR/CNR)
- Miserocchi Stefano (ISMAR/CNR)
- Zaccone Renata (IAMC/CNR)
- Lavezza, R., Dubroca, L. F. C., Ludicone, D., Kress, N., Herut, B., Civitarese, G., Cruzado, A., Lefevre, D.,Souvermezoglou, E., Yilmaz, A., Tugrul, S., and Ribera d'Alcala, M.: Compilation of quality controlled nutrient profiles from the Mediterranean Sea, doi:10.1594/PANGAEA.771907, 2011.";
    String title "Mediterranean Sea, Po River, DIVAnd 4D seasonal analysis of Water body chlorophyll-a 1978/2022 v2025 [observations]";
    String WEB_visualisation "https://emodnet.ec.europa.eu/geoviewer";
  }
}

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