09:30-09:45 Definition of final major CARBOOCEAN products (D1.11)Truls Johannessen

and all!

The North Atlantic observing system

An example of international synthesis (CARBOOCEAN)

U.Shuster, 2008, SOCOVV Meeting

The team:

Dorothee Bakker, Nick Bates, Robert Castle, Aymeric Chazottes, Antoine Corbière, Melchor González-Dávila, Betty Huss, Truls Johannesen, Arne Körtzinger, Nathalie Lefèvre, Heike Lüger, Nicolas Metzl, Cyril Moulin, Jon Olafsson, Are Olsen, Abdiraman Omar, Tony Padin, Fiz Pérez, Dennis Pierrot, Aida Ríos, Magdalena Santana-Casiano, Ute Schuster, Tobias Steinhoff, Kevin Sullivan, Taro Takahashi, Maciej Telszewski, Doug Wallace, Rik Wanninkhof, Andy Watson

, …and many others

Update from Seattle 02.10.2008

Benjamin working in symphony with Steve Hankings6.5 mill. data points at the moment.

SOCOVV meeting: 5 Regional groups identified with PIs - different progress in different regions (data availability, sampling and synthesis)- different questions: Interannual variability, decadal trends, River outflows, sea level change, forcing and feedbacks, climate index (ENSO, PDO, NAO, SAM, IOD, ….),…

PacificR. Feely

AtlanticU. SchusterN. Lefevre

Southern Ocean, B.Tilbrook

IndianV. Sarma

Coastal- Marg. SeaA. Chen, A. Borges

pCO

2 [μa

tm]

Sea surface pCO2 maps by MLR

CO2 fluxes into the North AtlanticThe future ?????????????

1995 climatology

CAVASSOO era

CarboOcean

Adapted from Schuster and Watson (2007), JGRWatson et al. (2008), in preparation

Air-

to-s

ea fl

ux [P

g C

year

-1]

0

0.1

0.2

0.3

0.4

0.5

Year

?

New CO2 time-series set up during CARBOOCEAN

SeaWiFs, September 2003

Two new CO2 time-series in the Atlantic

6oS, 10oW: since June 2006

(in the South Equatorial Current)

8oN, 38oW: since April 2008

(in the North Equatorial Counter Current)

10W40W

10S

CO2 sensor

(CARIOCA)on PIRATA mooring

Results from 6oS, 10oW (year 2006)

CO2 outgassing at this site except some

periods (June 2006) when near equilibrium conditions are observed.

Strong diurnal cycle after the upwelling season (see poster of Parard et al.)

DIC calculated from TA=f(S) and fCO2. Diurnal cycle observed in Sep. 2006 (from Lefèvre et al., 2008)

Status of time-series

SEP. 2008 4 DEC. 2008

6o, 10oW- June 2006 - June 2007: data validated- June 2007 - Sep. 2008: sensor back for calibration- Sep. 2008 - Present: working (figure above)8oN, 38oW- April 2008 - Present: working (some drift observed)

Meetings 2007Kiel in March

Delmenhorst in Nov./Dec.

Sponsored by: Hanse Wissenschaftskolleg,IOCCP and CarboOcean

Data coverage

The Nordic Seas The northern North Atlantic

North and Central Atlantic Southern Ocean

Data coverage

North Atlantic WG

• 85 cruises

• 28 „Core cruises“

• 7 of the „core cruises“ are GLODAP cruises (provides „golden standard“ and consistency with GLODAP).

• 1st step: Consisteny of „core cruises“.

• 2nd step: Consistency of „leaf-cruises“ vs. „core cruises“

• This is the main tool.

• We use only deep data (> 1500 m).

• Crossovers are made on density surfaces (on depth for salinity)

• Offsets considered multiplicative for nutrients and oxygen.

• Offsets considered additive for salinity, DIC, alkalinity and pH.

• Weighted offset and uncertainty of the Crossover.

Crossover analysis

Results from inversions of the cross overs guide 2nd level QC

An interactive website is the primaryforum for the CARINA members.

Defining individual cruise adjustments

Next steps

• Finalizing the Crossover analysis in early 2008• Final assessment of adjustments (or, the lack of) by May

2008. All lines of evidence uploaded on the website.• Final, „wrap-up“ meeting in Paris Meeting (June 18-19).

Consensus on adjustments (or lack of).• Product online shortly after that (late June?)

2

O X Y WA TC H

FP7 Cooperation Specific Programme for 2008Chapter 6: Environment (including Climate Change)Call ENV.2008.4.1.2.1 Monitoring and observing oxygen depletion throughout the different Earth system components

Study region

2

O X Y WA TC H

Study Region:Oxygen Float Pilot Study (WP3)Coastal Oxygen Glider Study (WP4)Atmospheric Oxygen Study (WP5)Synthesis, Modelling & Prediction (WP6)

Trends of ocean pCO2 in the North Atlantic Ocean(always near or above atm. CO2 sink is decreasing since 1990

Schuster et al., 2008, DSRII-SOCOVV Issue, in rev.

dpCO2/dt (µatm/yr)

Activity 3.2 - example:Elevated CO2/pH changes and Carbon cycling/ecosystem responses

Enhanced biological carbon consumption in a high CO2 ocean

• More carbon is taken up per unit nutrient under high CO2 ocean• Different mixing regimes within the bags• Dissociation constant???

Present21002200

Bellerby, et al, 2005.

Surface ocean pH reduction over this century will exhibit large regional variability

Reductions in pH this century will be greatest in the Arctic

Larger

Change in surface ocean pH in the 21st Century

Large

From Dorothee Bakker

Major products:1) The North Atlantic CO2 Observing network.2) CARINA data synthesis3) comparison of Cant calculation methods4) first evidence of long term variation in North Atlantic and SO CO2

sink.5) evidence of poorly understood role of sea ice in SO CO2 sink6) mapping of seasonal and annual North Atlantic CO2 fluxes etc.7) detailed time history of marine CO2 uptake from 1750 (or 1850)

until now, global and regional (basin wide) Christoph

In fact, the observational part CarboOcean is extremely successful.

Best regards, Fortunata – Swiss Clockwork• a) A comprehensive analysis of internal, naturallly-forced, and anthropogenic variations in marine ocean with a comprehensive

coupled carbon-climate model: T. L. Frölicher, F. Joos, G.-K. Plattner, M. Steinacher, and S. C. Doney. Natural variability and anthropogenic trends in oceanic oxygen in a coupled carbon cycle-climate model ensemble. Global Biogeochemical Cycles , in press, 2008.

• b) Quantification of regional air-sea fluxes of anthropogenic carbon and their uncertainties using six different reconstruction mehtods of anthropogenic carbon in an Ensebmle Kalman Filter approach: M. Gerber, F. Joos, M. Vazquez-Rodriguez, F. Touratier, and C. Goyet. Regional air-sea fluxes of anthropogenic carbon inferred with an Ensemble Kalman Filter. Global Biogeochemical Cycles , in press, 2008.

• c) Identification of the Arctic as a region that is expected to become undersaturated with respect to biogenic aragonite and quantification of the decrease in ocean volume providing habitat for calcifying organisms with a comprehensive coupled carbon-climate model. Results suggest that atmospheric CO2 should not exceed 450 ppm in order to avoid the risk of dangerous anthropogenic ecosystem interference:M. Steinacher, F. Joos, T. L. Frölicher, G.-K. Plattner, and S. C. Doney. Imminent ocean acidification projected with the NCAR global coupled carbon cycle-climate model. Biogeosciences Discuss., 5, 4353-4393, 2008.

• d) A comparison of the rates of change in natural and anthropogenic greenhouse gas forcing showing that current rates of increase in greenhouse gas forcing are unprecedented for at least the last 20,000 years, - a statement that has been included in the WGI Summary for Policy Makers of the recent IPCC report.F. Joos and R. Spahni. Rates of change in natural and anthropogenic radiative forcing over the past 20,000 years. Proceedings of the National Academy of Sciences USA (PNAS) , 105, 1425-1430, 2008.

• e) Constraining the magnitude of the air-sea piston velocity, a key parameter to estimate air-sea fluxes of CO2, with radiocarbon dataS. A. Müller, F. Joos, N. R. Edwards, and T. F. Stocker. Modeled natural and excess radiocarbon: Sensitivies to the gas exchange formulation and ocean transport strength. Global Biogeochemical Cycles , 22, GB3011, doi:10.1029/2007GB003065, 2008.

• f) A comprehensive multi-model assessment of the long-term consequences of anthropogenic emissions for the Earth system; results are also presented in the Technical Summary of the recent IPCC assessment.G.-K. Plattner, R. Knutti, F. Joos, T. F. Stocker, W. von Bloh, V. Brovkin, D. Cameron, E. Driesschaert, S. Dutkiewicz, M. Eby, N. R. Edwards, T. Fichefet, J. C. Hargreaves, C. D. Jones, M. F. Loutre, H. D. Matthews, A. Mouchet, S. A. Müller, S. Nawrath, A. Price, A. Sokolov, K. M. Strassmann, and A. J. Weaver. Long-term climate commitments projected with climate - carbon cycle models, Journal of Climate , 21, 2721-2751, 2008.

• g) An assessment of the importance of Southern Hemisphere wind changes in regulating atmospheric carbon dioxide concentrations.T. Tschumi, F. Joos, and P. Parekh.How important are Southern Hemisphere wind changes for low glacial carbon dioxide? A model study. Paleoceanography , 23, PA4208 doi:10.1029/2008PA001592, 2008.