The ocean-colour component of the Climate Change Initiative of the European Space Agency has generated a time series of bio-optical products from late 1997 to mid 2012. The products are based on data from SeaWiFS, MODIS-A and MERIS sensors, band shifted (to bring data to a common set of wavebands), corrected for inter-sensor bias, and then merged. Products include remote-sensing reflectances at SeaWiFS wavelengths, chlorophyll concentration, diffuse attenuation coefficient at 490 nm, and inherent optical properties (components of absorption and back-scattering coefficients). Practically all the products have uncertainties (root-mean-square difference and bias) associated with them on a pixel-by-pixel basis, based on validation using in situ data. The first version of the products are available freely at www.oceancolour.org and at www.esa-oceancolour-cci.org. A second version is expected to be released prior to the Blue Planet Symposium in Australia in 2015. Furthermore, plans are underway to add to the product suite through a number of related ESA projects. New products envisaged include primary production, photosynthesis parameters, components of the carbon pool in the ocean and photosynthetically active radiation (PAR) at the sea surface. User consultation and serving the user community are very much a part of these projects, and the Blue Planet provides a useful forum for reaching users from a variety of backgrounds. The work reported here contribute to components C2 (Sustained Ecosystems and Food Security) and C5 (Ocean Climate and Carbon) of the “Oceans and Society: Blue Planet” initiative of the Group on Earth Observations (GEO).

1. New ocean-colour products for the user community
Shubha Sathyendranath and Trevor Platt
Plymouth Marine Laboratory
UK

2. Chlorophyll fields are the most common products from ocean-
colour sensors.
But there is a growing need for other products.
OC-CCI chlorophyll product

3. New products being developed
under ESA projects
Include:
• Pools of Carbon in the Ocean (POCO Project)
• Marine Photosynthesis Parameters from Space (MAPPS Project)
• Photosynthetically Available Radiation (PAR Project)
One of the goals of these new projects is to engage new users, to
facilitate use of ocean-colour data for broader applications.
Activities relevant to Blue Planet C2 (Ecosystems) and C5 (Carbon
and Climate).

4. Rationale for POCO
• Standard ocean-colour product: chlorophyll
concentration; standard currency in marine-ecosystem
models: carbon or nitrogen
• Ocean-colour approaches to primary production:
chlorophyll-based; and ecosystem model approaches:
carbon-based.
• At the interface between models and Earth Observation
is the carbon-to-chlorophyll ratio, which is known to be
a highly variable quantity in the ocean
• In 2010, the Group on Earth Observations (GEO)
produced a “Carbon Strategy Report”. In response, the
CEOS commissioned its Carbon Task Force to produce a
CEOS Strategy document on “Carbon from Space”
(CEOS, 2014). Both GEO and CEOS Reports highlight the
importance of carbon products for a broad community
of users.

5. Pools of Particulate Carbon in the Ocean
• Total Particulate Carbon
• Particulate Organic Carbon
• Phytoplankton Carbon
Bigger
pool
Smaller
pool
Increasing
difficulty for
remote sensing
and in situ
measurements
Mor
e
data
Less
data
Main focus of the POCO project: Particulate Pools
NASA standard product, POC,
Stramski et al. 2010 June
New algorithms exist for carbon
pools.
Which algorithms are best for global
applications?
Can we validate them at global
scales?
Approach:
Create in situ database for validation
Compare products
Improve products where possible
Project is new: KO April 2015

6. Remote-sensing
algorithms
Particulate pools
Methods in
Ecosystem Models
Compare with in
situ database
Particulate pools
Best algorithms
Best models
Compare with
each other
Sufficient quality for
climate studies?
User workshop,
recommendations,
conclusions
Adaptable to
remote sensing?
Flow diagram showing approach to be used
• explore the potential of remote sensing for detecting particulate carbon pools in the
ocean
• compare with models
• focus on climate studies

7. MAPPS Project: Photosynthesis-Irradiance Parameters
Photo-physiological parameters are fundamental bio-optical properties
of phytoplankton and are at the heart of methods for estimating primary
production by remote sensing.
Pm
B provides information on the
maximum photosynthetic
capacity in the absence of light
limitation.
αB provides information on the
low-light efficiency of the
phytoplankton production.
We can also derive Ik, a measure
of the light level to which the
phytoplankton are acclimated.
RB
IC Ik
PB
I
αB
PB
m
Ÿ
Ÿ
Ÿ
Ÿ Ÿ
Ÿ Ÿ
Ÿ
Photosynthesis – Irradiance Curve

8. Importance of Estimates of Photo-physiology
Global coverage of P-I
parameters measured
directly at sea is relatively
sparse.
However, we must specify
them at every pixel, for
computation of primary
production using satellite
data.
The paucity of data necessitates development of extrapolation protocols for
assignment of photosynthetic parameters.
The MAPPS project explores satellite-based methods for estimating P – I
parameters.

9. New Agenda
Initial Results of Assimilation Number Algorithm Comparison
Assimilation number estimates
for July 2004.
Province-based (top-left),
Nearest Neighbour (top-right),
and Light-Temperature-
Biomass (bottom) based
methods.
What underlies differences?

10. JGOFS (FRUELA)
In situ database on Photosynthesis-irradiance parameters
for algorithm validation
Contributing Institutes

11. PAR Project
New Project KO: April 2015
Objectives:
• Improve ESA PAR products
• Extend to provide additional details (e.g. Extension to UV, direct and diffuse components,
spectral detail), according to user requirements
• Validate products
• Demonstrate applications
NASA SeaWiFS PAR Product

12. User consultation
• User consultation through a questionnaire, targeting users of
products, is underway.
• International workshop will be organised bringing together EO
scientists and scientists working on marine ecosystems to discuss
products and their applications (in 2016)
Blue Planet community has provided an avenue to engage users.
Thank you to all who provided feedback to survey.
The user feedback will be used to refine the project focus, as well as
to develop the scientific roadmap at the end of the project.