The ocean carbon cycle is changing at a rate whose magnitude and pattern we are only beginning to document, quantify, and understand. The uptake of anthropogenic CO2 from the atmosphere, climate fluctuations as well as long-term trends in ocean circulation and biology have led already to substantial changes in the ocean carbon cycle, with potentially larger changes looming ahead. In the last decade, substantial efforts have been undertaken to measure these changes, and a number of projects are underway to synthesize them and to put them into the context of climate variability and change. In particular, the SOLAS-IMBER carbon working groups jointly with IOCCP and other international organizations (e.g. PICES, EU FP7) have initiated and supported a number of analysis and synthesis activities such as SOCAT, CARINA and PACIFICA, with the goal to arrive at (i) homogeneous and quality controlled data sets and (ii) regional to global assessments of the changing ocean carbon cycle. This meeting aims to bring together the scientists working on these synthesis projects, but is open to all other scientists who are interested in developing an integrated view of how the ocean carbon cycle has changed in the recent decades. Of interest are data syntheses, analyses and modeling studies focusing on air-sea CO2 fluxes, changes in ocean surface and interior carbon properties, and how the changes in these realms are connected to each other. This meeting will provide critical inputs the further development of the ocean carbon observing systems, and to the next (5th) assessment report of the Intergovernmental Panel on Climate Change (IPCC). It will also form the basis of a number of planned synthesis papers. The meeting consists of plenary talks, poster sessions, and meetings of individual working groups.