C M E M S O c e a n C o l o u r S a t e l l i t e P r o d u c t s

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1 Implemented by C M E M S O c e a n C o l o u r S a t e l l i t e P r o d u c t s This slideshow gives an overview of the CMEMS Ocean Colour Satellite Products Marine LEVEL1 For Beginners- Slides have been prepared in Nov 2016

2 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

3 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

4 WHAT IS SATELLITE OCEAN COLOUR? (1/3) Marine SATELLITE OCEAN COLOUR is measured by a sensor called «spectrometer» on board of several satellites. Depending of the sea water constituents, 3 categories of colours can be observed: Chlorophyll-a, Non Algal Suspended Matter, Colour Dissolved Organic Matter.

5 WHAT DOES SATELLITE MEASURE? (2/3) Marine LIGHT emitted from the sun INTERACTS with the SEAWATER and its CONSTITUENTS before being captured by the remote spectrometer. Ocean Colour is the description of the optical properties of the medium through which the light propagates.

6 WHAT IS SATELLITE OCEAN COLOUR? (3/3) Marine Light emitted from the sun interacts with the seawater and its constituents before being captured by the remote spectrometer. The spectrometer spectral bands are then used for atmospheric correction and to retrieve seawater constituents. The main limitations are : Clouds, Spatial coverage (a few days are required to cover all points of the earth when only one satellite is available), and Spatial resolution : 300m 4km.

7 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

8 WHICH CHARACTERISTICS? (1/2) Marine Ocean Colour satellite data provide with Ocean Colour properties: In 2 dimensions (at the ocean surface, displayed on a 2D grid) Through a period of time: A reprocessing of the past (CMEMS provides with ~20 years in the past) An analysis of the current conditions No forecast into the future is provided.

9 CMEMS OCEAN COLOUR Satellite products provide with the following information: CHLOROPHYLL-A CONCENTRATION Chlorophyll-a concentration is a measure of phytoplankton s biomass integrated over the euphotic zone In Open Ocean, Chlorophyll-a uncertainity is influenced by phytoplankton s variability (Case I water). In Coastal Water, Chlorophyll-a uncertainity maybe influenced also by Suspended Particulate Matter and Colour Dissolved Organic Matter (Case II water). For each CMEMS Chlorophyll-A product, either the Case I or Case II algorithm is applied depending on the location (open ocean or coastal water). OPTICAL WATER PROPERTIES Reflectances Back scattering coefficient Light attenuation coefficient Absorption coefficient

10 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

11 W H A T I S C M E M S A D D E D V A L U E? ( 1 / 3 ) Marine PROCESSING LEVEL CMEMS PRODUCTS L0 L1 L2 L3 L4 Raw Satellite Data Raw Satellite Data with correction Derived geophysical variables at same resolution and location as L1 Variables mapped on space-time grid, with calibration, merging& validation Same as L3 but Gap Free Grid and with additional annexed information INCREASING ADDED VALUE OF SATELLITE DATA

12 W H A T I S C M E M S A D D E D V A L U E? ( 2 / 3 ) Marine REPROCESSING (20years in the past) Real Time Real time products: A new product update every day, a few hours after sensing Reprocessed products: A new product every 1 to 2 years with optimal accuracy and homogeneous time series

13 W H A T I S C M E M S A D D E D V A L U E? ( 3 / 3 ) Marine Calibration: all satellites are inter-calibrated, i.e. all satellites use the same reference level. Merging and Interpolation: satellite measures from one or several satellites are condensed as ONE VALUE on a REGULAR GRID : gridded product with gaps (L3) and gridded product without gaps (L4). Validation: products are scientifically validated following a thorough methodology. Algorithm and Corrections are specific to each European Sea characteristics.

14 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

15 C M E M S O C E A N C O L O U R T A C D A T A P R O D U C E R S

16 O U T L I N E What is Satellite Ocean Colour? Which Characteristics and Parameters? What is CMEMS added value? Who are the CMEMS Ocean Colour Data Producers? Which Satellite Ocean Colour Products in CMEMS catalogue?

17 WHICH PRODUCTS IN CMEMS CATALOGUE? (1/2) OCEAN COLOUR Satellite products over the GLOBAL Ocean and all European Seas are sorted into 2 categories: CHL: Chlorophyll-A L3 or L4 - Real Time and Reprocessed OCEANCOLOUR_(AREA)_CHL_(L4)or(L3)_(NRT)or(REP)_OBSERVATIONS_009_XXX OPTICS: Optical Water Properties (as Turbidity ) L3 or L4 - Real Time and Reprocessed OCEANCOLOUR_(AREA)_OPTICS_(L4)or(L3)_(NRT )or (REP)_OBSERVATIONS_009_XXX

18 A n y q u e s t i o n, a n y t i m e : s e r v i c e d e s k. c m e m m e r c a t o r - o c e a n. e u