TITLE:
The Use of Ocean-Colour Data to Estimate Chl-a Trends in European Seas
AUTHORS:
Giovanni Coppini, Vladyslav Lyubarstev, Nadia Pinardi, Simone Colella, Rosalia Santoleri, Trine Christiansen
KEYWORDS:
Chlorophyll-a; Trends; Eutrophication; Ocean Colour; In-Situ; Indicator
JOURNAL NAME:
International Journal of Geosciences,
Vol.4 No.6,
August
14,
2013
ABSTRACT: Ocean-colour remote-sensing products have been used to
estimate Chl-a trends in European seas with the aim to develop a new indicator
based on ocean-colour data for the European Environment Agency (EEA). The new
indicator, called CSI023(+), derived from
satellite ocean-colour products from the MyOcean Marine Core Service (www.myocean.eu)
has been defined and calculated. In our analysis, we have used 3 MyOcean
satellite products: 2 global satellite products (SeaWiFS and a merged product)
and one regional (adjusted to specific regional Mediterranean conditions)
ocean-colour product. We have evaluated the differences among the 3 different
products in estimating Chl-a trends. CSI023(+) complements the EEA CSI023
indicator for eutrophication based on chlorophyll-a (Chl-a) in-situ observations. Analysis
has revealed the potential of ocean colour as a CSI023(+) indicator to detect
large-scale, and in some cases, even local-scale, changes and decreasing trends of Chl-a were observed throughout the Black Sea, the Eastern
Mediterranean, the southern part of the Western Mediterranean, the English
Channel and the north part of the North Sea. Large areas with increasing trends
were observed in the Bay of Biscay, in the North-East Atlantic regions of
Ireland and the UK, in the northern part of the North Sea, in the Kattegat and
in the Baltic. Specific analysis has been performed in the Mediterranean
coastal areas using regional products to investigate local scale results. Validation
of ocean-colour products has been carried out through comparison with
observations of the Eionet EEA database. The validation results highlight that
regional products produced with regional algorithms are recommended for the
future.