• Establish the framework for repeated anthropogenic CO2 (Cant) inventory quantification within the Atlantic

Ocean basin, including its polar extensions and the European marginal seas

• Create interfaces between CarboOcean activities and related international activities in order to permit global ocean inventory estimates.

WP 3: Long Term Assessment

Where did we start?

after Sabine et al. (2004), Science 305, 367-371.

Column inventory of anthropogenic CO2 in the ocean (mol m-2)

Net uptake of anthropogenic CO2 (1800-1994):

118 ± 19 Pg C yr-1 = 48% of the emissions

WP 3

GLODAP – a product of a decade-long global effort

JGOFS/WOCECO2 survey

( GLODAP)

WP 3

CARINA – from a slow start to a CARBOOCEAN legacy WP 3

CARINA – already a CARBOOCEAN legacy

Anthropogenic CO2 methodology WP 3

CARBOOCEAN has populated the zoo of CT

ant methods

Did we agree on THE optimal method? – Not really, but ...

Vázquez-Rodríguez et al. (2009), Biogeosciences 6, 439-451.

Anthropogenic CO2 methodology WP 3

Two thing to learn:• the methods are rather robust• the differences point to general

weaknesses of general assumptions

Vázquez-Rodríguez et al. (2009), Biogeosciences 6, 439-451.

CARINA – from a slow start to a CARBOOCEAN legacy WP 3

Interior carbon synthesis WP 3

Resolutions:

• Address decadal carbon change basin by basin

• Calculate change in storage of both DIC and CTant

• Apply different CTant methods (e.g. C*, eMLR, TTD)

to evaluate robustness of the distributions

• Use a model-based analysis to provide „best practices“ recommendation for MLR-based approach

• Synthesize basin studies into global picture of the decadal change of interior ocean carbon storage

Atlantic

Pacific

Indian

Southern

Arctic

2012201120102009

Tanhua

Ishii

Sabine

Hoppema

Bates

Global Synthesis

Paper published

8/128/11

Basin-wideStudies

completed

2nd synthesisWorkshops

6/10 6/11

3rd synthesisWorkshop

Together withSOCAT

RegionalSynthesis

Paper published

3/12

GlobalStudy

completed

Data/Methods

By ocean basin

Cant, DIC

2nd QC Cant, DIC

interpolation

interpolation

2nd QC

Cant, DIC

Cant, DIC interpolation

Interpol 1 Interpol 2

eMLRdens interpolationRodgers?Key „best practices“

Interior carbon synthesis timeline – towards IPCC AR5 WP 3

The way beyond CARBOOCEAN: The OceanObs’09 vision

The way beyond CARBOOCEAN: Repeat Hydrography Program

WOCE CLIVAR

?

post-CLIVAR

~10 years ~15 years ?

The way beyond CARBOOCEAN: Repeat Hydrography Program

t

DIC

How to capture natural spatiotemporal variability

The way beyond CARBOOCEAN: ARGO Oxygen Program

The way beyond CARBOOCEAN: ARGO Oxygen Program

Objectives:

• Understand oceanic oxygen dynamics in view of their carbon-relevance;

• Establish temporal change of oceanic oxygen inventory;

• Improve atmospheric O2/N2 constraint on the oceanic uptake of

anthropogenic CO2;

• Help to interpret and interpolate sparse data from repeat hydrography occupations and ocean time-series;

• Refine oxygen boundary condition as a critical information for CTant methods

• Aid interpretation of variations in ocean circulation/mixing as well as net community and export production.