A monitoring system for heat and mass transports in the South Atlantic as a component of the Meridional Overturning Circulation Estancia San Ceferino, Buenos Aires, Argentina May 8, 9, and 10, 2007 May 8, 9, and 10, 2007

Objectives The main objective of this workshop is to get together scientists with current or proposed programs in the South Atlantic to foster collaborations leading to the establishment of a monitoring system for meridional heat and mass transports in the South Atlantic and inter- ocean exchanges as a component of the Meridional Overturning Circulation. The idea is to build upon what is already in place and to form international partnerships to augment the capabilities and therefore improve the results.

PROGRAM Breakfast: 7AM to 8:30 AM Coffee Breaks: 10:30 to 10:45 AM 3:00 to 3:15 PM Lunch:12:00 to 01:30 PM Dinner: 8PM

Proposed Agenda

Tuesday May 8, 9 AM to 12:00 Noon Session 1: 1.Introduction and objectives of the Workshop (Garzoli) 2.AMOC as a US Ocean Priority (Lindstrom) 3.Messages from Mike Johnson and Jim Todd (Garzoli) 4.The Aquarius/SAC-D Program (Lagerdof, Colomb) 5.Argo (Piotrowicz) 6.The South Atlantic Circulation and its role in Climate (Piola) 7.Inter-ocean exchanges. Large scale observations and models (Speich) 8.Will slowing of the MOC warm or cool Europe? (Nof) 9.The impacts of changes in the MOC on the south Atlantic climate and variability (Campos)

Session 2: Inter-ocean and Inter-hemispheric exchanges: This session will have the following format. Participants will be invited to make short (3 to 4 slides) presentations leading to answer the following questions for each of the three topics above: 1.Methodologies 2.What observations are in place? 3.What observations are proposed? 4.What is the objective of each one of the programs? 5.What are the observations telling us? 6.Can these plans be integrated to build an ocean-scale observing network/experiment? 7.What validation of models has already been done in the region? 8.What are the models telling us?

Session 2.1: Inter-ocean exchanges Pacific/Atlantic Session 2.2: Inter-ocean exchanges Indian/Atlantic Session 2.3: Meridional inter-hemispheric fluxes

Session 3: Three participants will de assigned to make a 15-minute summary presentation on Sessions 2.1, 2.2 and 2.3 (methodologies, models and observations). Creation of three working groups according to the (three) topics of session 2: Discussion: Are the current monitoring efforts sufficient? What else is needed? How to coordinate modeling and observational efforts? How build a coherent program from the various observational and modeling efforts

Session 4: (12:00 noon to 5 PM): Plenary. The design of an experiment for monitoring the SA component of the MOC. Review of the three groups General discussion and deliberations Assignments to write a plan. Adjourn 17:00 PM Thursday May 10

Ocean Climate Observation Program Request to The SAMOC Workshop Buenos Aires, Argentina 8-10 May 2007 Mike Johnson Director, Ocean Climate Observation Program photo courtesy of MeteoFrance

Introduction to the OCO

Ocean Climate Observation Program Ocean Climate Observation ProgramMission Build and sustain a global climate observing system that will respond to the long-term observational requirements of the operational forecast centers, international research programs, and major scientific assessments. *Focus on the in situ Ocean component.

Fundamental Climate Requirements Document long term trends in sea level changeDocument long term trends in sea level change Document ocean carbon sources and sinksDocument ocean carbon sources and sinks Document the ocean’s storage and global transport of heat and fresh waterDocument the ocean’s storage and global transport of heat and fresh water Document the ocean-atmosphere exchange of heat and fresh waterDocument the ocean-atmosphere exchange of heat and fresh water

Capabilities Required  Global coverage by moored and drifting buoy arrays, profiling floats, tide gauge stations, bottom-mounted and ship-based systems. Continuous satellite missions for sea surface temperature, sea surface height, surface vector wind, ocean color, and sea ice.Continuous satellite missions for sea surface temperature, sea surface height, surface vector wind, ocean color, and sea ice.  Data and assimilation subsystems.  System management and product delivery.

Special request to the SAMOC Workshop

A sustained global observing system is the foundation of all climate research and services. A global system by definition crosses international boundaries with potential for both benefits and responsibilities to be shared by many nations. Climate models predict that changes in global ocean circulation may trigger epic changes in Earth’s heat exchange between the tropics and the higher latitudes, resulting in rapid climate change. NOAA, the U.S., and the World need a global ocean observing system capable of delivering continuous near-real-time measurements that will provide:  Data sets for model validation and quantitative assurance that the model projections can be reasonably accepted or rejected.  Quantitative ocean indicators at a few strategic locations, to alert the nation and the world if major changes are occurring. In order to effectively support advancement of the global ocean observing system, the OCO needs:  Scientific advice defining the best next-steps toward fielding the required sustained ocean observation and analysis system.

Thank You

Message from Jim Todd Please mention that we are in the next phase of our planning for the FY08 ORPP near-term priority on AMOC. Potential funding for NOAA is $5M in FY08, but this of course has to be blessed by Congress this summer. NSF has also been identified for funding in FY08, but we do not yet know who (i.e., which programs) would benefit. NASA, unfortunately, did not get funding for this activity in FY08, but we hope that they will in the out-years. I wish everyone well at the meeting. If there was one request to the group - and I realize that this is very difficult to do - I would like to see people not pitch only their pet-rocks. We need to have credible input as agency program managers. If it looks like a laundry list of requests for funding, our efforts in pushing an AMOC initiative will undoubtedly fail. People should challenge each other's point-of-view in order that we get the best product out of this workshop. Thanks for the opportunity to comment. Please have a big, juicy Argentine steak for me (and a nice bottle of Malbec)! Best regards, Jim

Message from Arnold Gordon Silvia- You might want to come out of your 'Estancia San Ceferino' meeting with a concise statement of <1 page concerning the South Atlantic's active role in maintaining the Atlantic MOC. Clearly the S.Atlantic subtropical gyre salinity would be very different if its Sverdrup transport were closed by the low salinity South Atlantic Current rather than Indian Ocean subtropical salt introduced by the Agulhas leakage. The Agulhas leakage pre- conditions the Atlantic as a site of major MOC. Its change in paleo-times seems linked with the Atlantic MOC intensity. On a more speculative level, there may also be fluctuations in the pathways [perhaps involving the Brazil-Malvinas Confluence] followed by Pacific water entering the Atlantic via the Drake Passage that could alter the Atlantic salinity. Another aspect is how the South Atlantic and North Atlantic waters maneuver their way across the zonal circulation and upwelling fields of the tropics. The statement should be independent of whatever monitoring strategy you come up with. Its intent is to make clear the underling science questions, so that NSF and NOAA do not neglect the Atlantic at, or south of the Equator. I would hope that they would entertain not just in situ ocean monitoring and research projects in the South Atlantic, but also further ocean/climate modeling and paleo-climate research to do with interocean exchange and cross equatorial transport relevant to the MOC. I would gladly 'sign' [and help draft] such a statement. Arnold