1. The review for 2007 and how to address it in annual report for 2008 EU FP6 Integrated Project CARBOOCEAN ”Marine carbon sources and sinks assessment” 4 th Annual Meeting – Dourdan France Germany 8-12 December 2008

2. All: Read the reviews and relate to the critical point when writing your reports All issues as raised by the reviewers must be re- addressed by the Core Theme Leaders and Work Package Leaders in their annual reports to be delivered. We may get new external reviewers, please, take previous review extra seriously.

3. Positive aspects: -We have not been tempted to drift into the acidification topic which is more dealing with impacts than carbon fluxes as such. CARBOOCEAN will collaborate with the research project EPOCA on ocean acidification, where CARBOOCEAN can deliver the framework data (timing and extent of pH changes on various scales), while EPOCA will in detail look at processes. CARBOOCEAN is nevertheless addressing the topic as far as it is important for the feedback to climatic change, i.e. the carbon fluxes. -We are happy to see that our efforts to produce a video/documentary on the project and the ocean carbon uptake of anthropogenic CO2 are acknowledged. It is good to know that this product would fill a gap in the present outreach material. The school project CarboSchools/CarboSchools+ has received very positive attention. -WP10: The O2 float development has made good progress now and this is acknowledged. -CARBOOCEAN efforts on international collaboration in the field are visible. This is encouraging. -Gender issues: CARBOOCEAN’s activities towards gender equality have been acknowledged by the reviewers. We nevertheless would have liked to see a mentioning of this also in the consolidated report.

4. Critics: -V. Brovkin mentioned a delay in the WP1 uncertainty assessment, and is missing a rationale behind this. The reason is that we decided not to make preliminary statements before the final Earth system model runs have been analysed thoroughly. These final runs will also include recent updates. In order not to confuse the outside world we decided to wait until the final outcome. -We will give improved guidelines on a more “synthesis-like” reporting on the work packages, so that too complex wording and structure such as in the WP12 report can be avoided. WP16 can be used as a positive example on how it optimally should be done. -WP13 delivered to the core theme leader and coordinator a detailed reply in view of the reviewers’ comments. According to this, the WP does not drift more into research on the entire Mediterranean in general or the eastern Mediterranean. Rather, through the BOUM cruise a link to the SESAME IP could be created which should be regarded as a surplus to CARBOOCEAN. The work in the Strait of Gibraltar has certainly been acknowledged by the reviewers. -The potential of oil rig measurement contamination (WP14) is well known to the scientists involved. Flask measurements are only made at those wind conditions, where contamination can be neglected.

5. Things to address I: -For the last 1.5 years and the final outcome of the project we aim as much as possible to come to syntheses on ocean-atmosphere CO2 fluxes – however intermediate in an absolute sense they may be. This will be important to communicate our results to policy makers, decision makers, teachers, and the general public. -In order to involve all relevant stakeholders: CARBOOCEAN is in the process to write together with CarboEurope IP an integrated carbon cycle assessment report including a synthesis of results and needs for future research priorities. Further, the European Commission together with the relevant other greenhouse gas projects aim at organizing an EU GHG conference (was too ambitious, maybe a 1-day event in Brussels soon) to discuss the results achieved so far and the needs for future research with all parties involved, so that we can tailor our research in a corresponding way.

6. Things to address II: -One key issue is to sustain current ocean carbon observations and extend them in spatial as well as temporal coverage, in particular at key regions for anthropogenic carbon buffering. One of these regions is the Southern Ocean, which is notoriously difficult to access. An extended international effort would help here to improve the situation for carbon system measurements in the Southern Ocean. Arctic needs to be considered as well… -V. Brovkin addresses the resolution issue for current Earth system models and their marine components. At present we are in the dilemma of being with the horizontal resolution of these models close to the boundary of feasibility in view of computer resources and number of experiments to be carried out. Certainly, an attempt to establish a common European Earth system model on a suitable supercomputer platform would also be very attractive from the point of view of CARBOOCEAN modellers. On the other hand, Earth system and ocean model developments are still in a situation, where different model approaches and “schools” are needed in order to properly address the issue of uncertainties. One single model, however high its resolution and sophistication would be, would not be sufficient to establish a realistic uncertainty range in model results as yet. This is in particular the case for future scenarios. -The reason for the varying North Atlantic CO2 sink (Irminger Sea, Nordic Sea, Labrador Sea, entire North Atlantic sub-polar as well as sub-tropical gyres) is under analysis also using stand-alone ocean models. It is expected that we have an improved attribution analysis at hand in about 1 year from now.