1. NOAA Climate Program Office Climate Observations Division PI Meeting
David M Legler
Climate Observation Division
N A T I O N A L O C E A N I C A N D A T M O S P H E R I C A D M I N I S T R A T I O N

2. Background All about me Science/research mutt
Ocean remote sensing, air-sea interaction/fluxes, ocean surface observations, ocean data management (WOCE), ocean modeling, ocean data assimilation, climate forecasting applications (agriculture), CLIVAR (broad range of research activities….interagency)
Working with people and programs
No experience as a program manager (except vicariously)
After 16 months, still learning!
Thanks for your patience and support 2

3. We have had supportive leaders within NOAA
Observations & Monitoring Program Welcome to NOAA! Immediate Impressions
Great and talented partners: labs, universities, other agencies, international
We have had supportive leaders within NOAA
Dedicated (& hard working) team (ie COD)
COD and its partners contribute critical capabilities to research, prediction, monitoring, and assessment communities
I’ve discovered why program managers always seemed busy….because they are….Planning, managing, coordinating, integrating, executing, assessing, meetings!
Some activities/decisions are easier to explain than others 3

4. Committee Work and Leadership [recent topics discussed]
Observations & Monitoring Program Welcome to NOAA – please help!
Committee Work and Leadership [recent topics discussed]
Within NOAA
NOAA Obs System Council (NOSC) – Dr Sullivan, Chair [Prioritization of obs systems across NOAA, data mgmt, etc]
Fleet Council – Adm Bailey, Chair [Fleet allocations, management]
Satellite requirements groups (2)
Interagency
Interagency Ocean Observations Committee (IOOC) – Co-Chair along with Eric Lindstrom/NASA and Bob Hautman/NSF [Interagency coordination and planning of ocean observations and IOOS oversight]
US CLIVAR Inter-Agency Group – WCRP [research/interagency coordination] 4

5. What I Learned Over the Past 16 Months Program Health
Observations & Monitoring Program Outline
What I Learned Over the Past 16 Months
Program Health
Considerations for the Future
FOCUS TODAY ON Ocean Climate Observations 5

6. Highlights
Observations & Monitoring Why We Observe the Ocean
Thanks to the efforts of the international community developed over the last 2 decades, we are now observing the surface and global upper ocean systematically for the first time in history.
It is a major international achievement and the OCO program has played a central role in developing the in-situ components 6

7. State of the Global Ocean
Observations & Monitoring Program FY11 Highlights – Integrated Ocean Status
Quick easy to use Indices and trends for Ocean Sfc and Subsurface, Ocean-Atmosphere, and Sea Ice
NOAA NCEP GODAS Analyses

8. Observations & Monitoring Program FY11 Highlights - Argo
New uses of Argo observations (Salinity and trajectory) to explore ocean dynamics
Interannual Variability: Globally-averaged T (left) and S (right), highlighting the ENSO anti-correlated variation of the surface layer (0 – 100 db) and the db layer. From: Roemmich and Gilson (2011, Geophys. Res. Lett.)
Ocean Circulation and Transport: Absolute geostrophic pressure field at 5 db based on combined Argo trajectory and profile data. CI = 10 dyn cm. From: Gray and Riser, 2011, in prep) 8

9. Persistent Antarctic Bottom Water Warming
Repeat Sections document large, persistent changes in Southern MOC
AABW flows north through the
Vema Channel as part of the MOC
The 2011 reoccupation of A10
crossed the Vema Channel
Zenk and Morozov (2007, GRL)
showed AABW warming in the Vema Channel by about 0.03 ºC per year since the 1980s
An update including the 2011 data shows the coldest AABW in the Vema Channel has warmed by 0.1 ºC since the 1970s. Part of a global contraction of AABW over that last few decades.
M. O. Baringer, A. M. Macdonald,
& G. C. Johnson

10. Observations & Monitoring Program FY11 Highlights – Global Drifter Program
Right: time series of the latitude of the Brazil-Malvinas Confluence in the Southwest Atlantic Ocean, showing a significant southward shift in last 15 years. Position derived from a synthesis of drifters, altimetry and wind products (Lumpkin and Garzoli, 2011).
Southward shift of Brazil-Malvinas Current
Tsunami Debris Field Evolution
(Please note that a larger list of scientific achievements is given in the FY11 report; here are two highlights.)
Lumpkin and Garzoli (2011) described interannual to decadal variability in the position of the Brazil-Malvinas confluence front of the southwest Atlantic Ocean using a synthesis of drifter-derived currents, altimetry, and wind products. They showed that the annual mean position of the front shifted significantly southward by over 100km during 1993—2000, corresponding to a shift in the wind stress curl over the South Atlantic basin. At longer time scales, NCEP data was used to infer the position of the confluence front based on these results, and deduce that the southward shift was part of a multi-decadal oscillation related to SST anomalies advected from the Indian Ocean along the Agulhas-Benguela pathway of the southeastern Atlantic.
N. Maximenko used drifter observations to derive a statistical model of particle advection/diffusion by upper ocean currents, and applied this to simulate the evolution of the field of debris released from Japan in March 2011 as a result of the earthquake and tsunami. This drifter-derived model result, indicating potential impacts on Hawaii by 2013, received significant media attention. This model has now been improved to better simulate where particles run aground, as documented in Lumpkin, Maximenko and Pazos (J. Tech, in press).
Left: simulation of March 2011 tsunami debris field evolution, using drifter-derived advection/diffusion statistics (N. Maximenko, Univ. Hawaii). 10

11. Highlights
Observations & Monitoring Program FY11 Highlights – Sea Level
Unprecedented Sea-level rise in the Western Pacific – winds to blame?
Tropical pattern of increasing SL in western Pacific can be explained by winds…what explains the non-tropical pattern?
Linear trend ( ) of satellite altimeter SSH showing the region of high rates in the western Tropical Pacific. Vectors denote ECMWF wind stress trends for the same period. The inset is the time series of average sea level obtained from 11 tide gauges (tide gauge locations denoted by solid dot) (from Merrifield and Maltrud, 2011). 11

12. Nagura and McPhaden, 2010, J. Geophys. Res.
Observations & Monitoring Program FY11 Highlights – Tropical Moored Arrays
Linear Equatorial Wave Model Validated with Observed RAMA Transports (0-100 m) at 0°, 80.5E
Caption: Weekly time series of zonal transports at 0°, 80.5°E for ADCP observations (gray shades), full model (solid line) and K-R1 model (dashed line). K-R1 Model is based on just the Kelvin wave and first meridional mode Rossby wave of the first and second baroclinic modes.
Note: the excellent comparison between the full model and observations; and the K-R1 model and obs. Correlation between K-R1 model with obs (0.84) is actually higher than with full model and obs (0.81)
Solutions near the equator are dominated by the the Kelvin + 1st meridional mode Rossby wave of the two gravest vertical modes
K-R1 Model is based on just the Kelvin wave and first meridional mode Rossby wave of the first and second baroclinic modes.
Nagura and McPhaden, 2010, J. Geophys. Res.

13. - Observations & Monitoring Program FY11 Highlights – Ocean Carbon
The 7 year time series at the MOSEAN H-A/WHOTS mooring site shows an increasing trend in ocean and atmosphere CO2.
RECCAP (REgional Carbon Cycle Assessment and Processes)
Is there a trend in global net carbon flux?
Climatological global net sea-air CO2 flux +
CO2 release
CO2 uptake -
-1.19 Pg (1015) C yr-1

14. Ocean Freshwater flux (EOAFlux – PGPCP) 1979-2008 (Lisan Yu – WHOI)
Observations & Monitoring Program FY11 Highlights – Analyses
Validation of Satellite-Derived Air Temperature and Humidity (accurate input for surface fluxes) – Smith and Bourassa (FSU)
Right: Map of the 2010 annual surface salinity anomaly estimated from Argo data [colors in
PSS-78] with respect to a climatological salinity field from WOA 2001 [gray contours at 0.5
PSS-78 intervals]. White areas are either neutral with respect to salinity anomaly or are too data- poor to map. While salinity is often reported in practical salinity units, or PSU, it is actually a dimensionless quantity reported on the 1978 Practical Salinity Scale, or PSS-78. Figure after Johnson and Lyman (2010).
Time series for the World Ocean of ocean heat content (1022 J) for the m (red) and m (black) layers based on running pentadal (five-year) analyses. Reference period is From Levitus et al. (2012)
Ocean Freshwater flux (EOAFlux – PGPCP) (Lisan Yu – WHOI) 14

15. Glider alongshore flow: mean and 0-500m variability
Observations & Monitoring Program FY11 Highlights – California Current Gliders
Data products consist of profiles of temperature, salinity, density, velocity, chlorophyll fluorescence, and acoustic backscatter on uniform grids along all lines. The resulting sections allow calculation of the transport of such quantities as heat, salt, phytoplankton, and zooplankton (Send and Rudnick /Scripps)
We (and SCOOS) are supporting 2 of only 3 routine glider transects in the US
Now 5 years of glider observations every approx. 3 weeks along line 90 (Hovmueller diagram shows only first 3 years of 0-500m depth-averaged alongshore velocity as illustration).

16. Program Overview Observations & Monitoring Program Program Overview
FOCUS TODAY ON Ocean Climate Observations 16

17. Observations & Monitoring Program Climate Observations Division
David Legler, Division Chief
Our mission is to develop and sustain, with national & international partners, an in situ global observing system to monitor, understand, & support prediction of the coupled ocean, arctic, & atmosphere systems;
To provide long-term, high quality, timely global observational data, information, and products in support of communities of researchers, forecasters, other service providers, and users, for the benefit of society
Key Activities
Global Ocean Observing System
Arctic Research and Arctic Observing Network
Monitoring
Strategic Partners
NOAA Ctrs/Labs (PMEL, AOML, GLERL, GFDL, CPC, EMC, NCDC, NODC, ESRL, ), US Navy, …
Academia (Scripps, WHOI, UW, Miami, FSU, CIs)
Int'l Research Programs in Europe, Asia, Russia, etc and engaged/coordinated through bilaterials, IOC, and efforts like Argo and GLOSS.
GLOSS Sea-level array, Tropical Moored Buoy Array, Argo array, Arctic sea ice drifters (1997-left, 2009-right) – all international systems
From the bottom of the ocean to the top of the atmosphere, NOAA’s instruments are part of an international system to monitor the Earth’s climate system.
The Climate Observations and Monitoring (COM) Program designs, deploys, and maintains an integrated global network of oceanic and atmospheric observing instruments to produce continuous records and analyses of a range of ocean and atmosphere parameters. COM coordinates observing efforts across NOAA and other federal agencies, as well as internationally. The monitoring portion of the Program ensures that the data sets researchers need to understand the climate system are available for analysis. The Program documents and studies variations in climate on time scales ranging from less than one year to periods of 100 years and longer, i.e., both instrumental and paleoclimate eras. The monitoring effort also provides data and information management support for national and international climate assessment projects. Analysis products support other Climate Program Office efforts in modeling of the climate system and development of targeted services to better inform society about climate impacts and response options.
Support of NCS through monitoring
Production of data sets from research through operations
Production of data sets at global and regional scales
Provision of data sets for initialization/validation of model predictions at global and regional scales (e.g., the Arctic)
Long, continuous, high resolution data for impacts analysis (e.g., weather/climate extremes)
ARCTIC
– initiated concept for circum Arctic network of atmospheric climate observatories and provided foundational support for establishment of observatories in Canada and Russia
-reinvigorated bilateral ocean science agreement between US and Russia, and launched joint observation activity focused on US and Russian territory in the Bering Strait and Chukchi Sea
 - leads international planning for sustained marine observations, including Arctic Council's marine biodiversity monitoring program and the Pacific Arctic Group, initiator of the Distributed Biological Observatory concept

18. Critical Partners contributing resources
Observations & Monitoring Program Critical partners contributing resources
All observing activities supported by the Climate Observation Division are in partnership with other countries, including:
Argo: 34 countries
Arctic : 13 countries
Global Sea-Level System: 57 countries
Surface Drifters: 14 countries
Tropical Moored Buoy Arrays: RAMA (15) and PIRATA (3)
International partnership and coordination is the most economical and sustainable pathway to achieve global observation coverage
“The substantial commitment of NOAA to support in situ and satellite observations of ocean climate has been critical to building a Global Ocean Observing System. GOOS is delivering data and information for research and services to all Member States of the Intergovernmental Oceanographic Commission to help manage our relationship with the natural system and to build a sustainable future.”
Albert Fischer, Ph.D. Director, GOOS Project Office
US contributes about 50% of the global ocean observing system

19. Observations & Monitoring Program Arctic Research
Arctic Research produces unique and multi-disciplinary observations for the Arctic region, including:
Bering Straight/Chukchi Sea/Pacific Arctic, heat, fresh water and ecosystem changes;
Sea-ice drift and ice mass;
Time series of essential climate variables
at Atmospheric Observatories
International partnerships
(Russia, Canada, Pacific Arctic Group)
Recent Highlights:
NOAA’s Arctic Vision and Strategy (2011)
Sea-Ice Forecasting Workshop (2011)
CPO/Arctic priorities embedded in NOAA, IARPC and NOC plans (2012)
Arctic Council Marine Monitoring Plan
FY12 Milestones:
Arctic Report Card
Quadrennial RUSALCA cruise in Bering Straight and Chukchi Sea
sea ice image
Observing, understanding, and prediction of the Arctic where the environment is particularly sensitive to climate variability and change. 19

20. Observations & Monitoring Program Monitoring Activity: Detection and Attribution
Detection and Attribution projects are aimed at providing data and tools needed to make authoritative statements about the degree to which man-made influences are showing up in the climate system. These projects produce research publications and attribution knowledge and capabilities.
Recent Highlights:
Extension of attribution studies beyond initial global-scale atmospheric temperature to address regional scales and other variables, e.g. precipitation
Increased attention to the occurrence and attribution of single events that have large impacts on society (e.g., weather and climate extremes)
Partnerships: With DOE, support grants in detection/attribution and international scientists participating in the International Detection and Attribution Group (IDAG)
Opportunities:
Detection: support monitoring of historical extremes and compare with model projections of future extremes
Attribution: forge new alliances to address key issues (CPO programs, other agencies, international research institutions).
Future Phases:
Maintain core detection/attribution focus but continue to expand into new areas like impacts attribution and event attribution.
Support emerging activity of the ESRL-led Attribution of Climate-related Events group, with a focus on establishing routine attribution
“A key challenge for the community is to move beyond research-mode case studies to develop systems that can deliver regular and timely assessments in the aftermath of extreme events.”
—Scott, et. al. “Attribution of Weather and Climate-Related Extreme Events. Published in Nature: September 8, 2011 20

21. Observations & Monitoring Program Return on Investment
For a $45M investment in the Climate Observation Division (COD) by Congress through CPO, COD provides:
Sustained global observations of essential climate variables in the ice-free ocean to 2000m depth
Key observations of the Arctic region’s climate to document variability, detect change, and evaluate impacts on marine ecosystems
Monitoring and long-term records of critical climate variables such as global sea-level change, SST, ocean thermal/heat uptake, sea-ice, and ocean carbon which meet the long-term observational requirements of forecast and modeling centers, international research programs, major scientific assessments, and decision-makers
The foundation for US (and world) S-I forecasts
International partnerships and infrastructure leading to the growth of a Global Climate Observation System
High quality products & reports to inform decision-makers and the public
Authoritative updates to the public: The Annual State of the Climate (one of the top 10 AMS resources downloaded) as well as the Arctic Report Card
Improved science & knowledge for the nation/society – Without climate observation and monitoring activities in COD we would likely NOT have
Useful climate and weather predictions on intra- to interannual time scales – which lead to a wide array of adaptation activities in multiple sectors (e.g. water, agriculture, commerce)
Long-term climate records quantifying and describing the ocean’s role in global energy balance and sea-level change
Adequate characterization of the trends and variability in the Earth’s climate
Information contributing to the development and improvement of early-warning systems of extremes such as droughts
Global and regional estimates of carbon uptake and storage by the ocean
Estimates of the trends in hydrometeorological extremes, e.g., precipitation, flooding, drought, heat waves
Jobs – in addition to direct support of over 50 FTEs and innumerable others via contracted services, development and manufacturing of instruments and sensors supports jobs in many small businesses and helps maintain US technical leadership in ocean observing technology 21

22. Highlights Budget (past, present, and future) External Forces Risks
Observations & Monitoring Program Program Health
Budget (past, present, and future)
External Forces
Risks
Concerns 22

23. Division Spending FY12 (FY11)
Observations & Monitoring Program Budget
Division Spending FY12 (FY11)
Climate Observation Division $45M ($49.5M)
Ocean Observing
$37.5M ($39.5M)
Arctic
Program
$3.7M ($4.5M)
Climate Monitoring
$3.7M ($5.5M)
CPO hit with 21% reduction
COD hit overall was 9%
Direction to protect long-term observational record and activities in support of NOAA’s mission not undertaken elsewhere
Some funding sources were not cut
Operational costs for some elements fluctuate from month to month (e.g. communications and ship time)
Diane Stanitski, Candyce Clark, Sidney Thurston, Joel Levy, Steve Piotrowicz
John Calder, Kathy Crane
Chris Miller, Bill Murray
Summer Intern: Amanda Laurier 23

24. Observations & Monitoring Program Budget History24

25. Reduced support of some technology development
Observations & Monitoring Program FY12 Budget Reduction Impacts
Small budget reductions in many observing activities. Nearly all global observing capabilities maintained (but with increased risks and reduced scientific involvement). XBT program focused reductions.
Significant reductions in support of ocean data assimilation (primarily at GFDL, NCEP)
Reduced support of some technology development
Analysis efforts reduced. A few product and analysis activities zeroed.
Maintained some investment in deep Argo technology development 25

26. President: $4.6M increase for COD
Observations & Monitoring Program Prospects for FY13
President: $4.6M increase for COD
Senate: CPO funding = President’s budget
House: CPO funding = FY12 less $18M, “Committee recommends a more balanced funding allocation across NOAA’s research programs”…????
Outcomes at COD level: ???
GOOS Increase would increase these activitie::
Ocean Reference Station, tide-gauge stations, ocean analysis, drifters, SAMOC, deep argo initial array, and some Arctic observing 26

27. Not everyone has indicated that risks have increased
Observations & Monitoring Program Capabilities and Risks
We’ve heard the message: Several years of stagnant budget are eroding capabilities and increasing risks
Risks include loss of data, instrumentation, spares (thereby increasing risks of observing cessation), personnel, data quality and timeliness, etc
Not everyone has indicated that risks have increased
Program managers will assess this information as we start planning for FY13 and beyond 27

28. There is no clear prioritization of observing activities
Observations & Monitoring Program Perceptions (as the incoming director)
A collection of activities… the observing “system” is not uniformly developed or organized
However, many pieces are highly efficient and overall the system has made tremendous progress towards the global ocean observing system vision
There is no clear prioritization of observing activities
Demonstrating and communicating value/impact of current/future system sometimes difficult and not a part of our DNA
Program information not available online
Data search/access sometimes a challenge 28

29. Observations & Monitoring Program Concerns (after a year)
Sustainability of the Observing System
It’s complex, has a lot of moving and aging parts, needs lots of love and care…. Maintenance and “refurbishment” become more important as time goes on.
Expectations that COD will provide product and science support conflicts with mandate to sustain observing system (need both).
Downward Budget Pressure
Overall federal budget will likely remain flat or decline for next few years. Observations are an important NOAA activity. But NOAA is challenged to support current and planned observing needs. NOAA is assessing and prioritizing its observing systems.
Declining NOAA Fleet and Charter Fund resources
Requirement for global-class ship capability will remain for foreseeable future- Without adequate ship resources, parts of the global ocean observing system for climate that have been developed over the past 15 years are in peril (Tropical arrays, carbon buoys, deep ocean hydrography, etc).
How does the program initiate new things and new technology (in light of above)
NOSC/NOAA is prioritizing observing systems across NOAA
Effort underway to assess observing across federal government
Critical role, and increasing importance of, international partnerships
NOAA-RAS & NOAA-Roshydroment Bilateral, Arctic theme – a must for Arctic work
India, Indonesia, & others for ship time and contributions to the ocean obs system
Pacific Arctic Group, cruise/data coordination, Distributed Biological Observatory 29

30. Highlights Where are we going?
Observations & Monitoring Program Considerations for the Future
Where are we going?
Addressing program needs (what should we do!) 30

31. Developing the Global Ocean Observing System for Climate Status against the GCOS Implementation Plan and JCOMM targets
Total in situ networks
61%
May 2010
87%
100%
62%
The value/notion of completing 100% of array does not easily translate into payoff/outcome!
81%
100%
Congrats on getting this far! However,
A strategy ramping to 100% of planned systems is insufficent to argue for increased resources. Must tie more tightly to needs (research, prediction, monitoring of key variables, etc) leading to
24%
48%
79%
43%
System % complete
Target 100%
A total of 8483 in situ platforms
are maintained globally.
Of these, 4207 are supported
by NOAA.

32. Observations & Monitoring Program Translating Increased Observing into Impacts
Observing, Understanding, Predicting, and Monitoring
Sea level
Ocean carbon sources and sinks
The ocean’s storage and global transport of heat and fresh water
Sea surface temperature
The air-sea exchange of heat and fresh water
Sea ice extent
Ocean biological changes associated with environmental changes (e.g. in Arctic)
Impacts on Products and Immediate Customers
Metrics/diagnostics (and their uncertainties), products, models (uptake and results)
Value beyond
Climate variability and change (e.g. ENSO, MJO, Monsoons, Indian Ocean Dipole, decadal and longer variations), extremes, inundation, floods, droughts, hurricanes, ecosystems, agriculture, commerce, safety, policy, etc
Global Average
Sea Level Change
Ocean Storage
of CO2
World Ocean
Heat Content
Are these the important values and ocean attributes this program pursues?
What is the added value of say a 10% increase in observing platforms/budget?
We may not have to explicitly describe and tie proposed increases/decreases to every use/product/model/outcome, but we need some work in this area.
Global Average
Sea Surface Temperature
Arctic Sea Ice Extent
National Oceanic and Atmospheric Administration (NOAA) 32 32

33. Highlights
Observations & Monitoring Program Addressing Program Needs
Resources
THERE WILL BE OPPORTUNITIES! Be Prepared!
Develop strategic perspective (Wed morning) overall and within individual program activities. What initiatives are ready for FY14/15?
Improve the scope and availability of information and reporting (ie metrics) characterizing health, status, performance, and impacts of our activities (Wed morning)
Program activities and performance should be more strongly tied to science/research/monitoring goals. Develop a means to review programs to provide feedback and assess progress on these goals. Some programs may have to be terminated.
Look for opportunities to partner with other programs to expand observing capabilities (e.g. bio-Argo with Argo, CCE moorings, etc) 33

34. Highlights Resources (2)
Observations & Monitoring Program Addressing Program Needs
Resources (2)
Develop a portfolio of program impact materials describing impacts/value of observing efforts
Improve awareness and encourage support (and corresponding budget) within NOAA and elsewhere for research/obs activities (communications, messaging, and engagement)
Keep fighting internally for appropriate ship resources
Increased attention to potential bilateral “Resource Sharing Agreements” for ship time
Look for efficiencies/alternate strategies for ship scheduling for mooring servicing
New technologies may help (and may an attractive “sell” to NOAA if they help reduce reliance on ships), but introducing them into climate observing system has to be done carefully – what is our strategy and timeline for developing, considering, and incorporating evolutionary and revolutionary technologies? (Wed PM)
IOOS Summit 34

35. Highlights Sustaining the System Needs More Attention Outward Focus
Observations & Monitoring Program Addressing Program Needs
Sustaining the System
Define what it takes to be sustainable, e.g. best practices/attributes of a sustained observing activity.
Identify those activities that should be “sustained” and those that are still in pilot or pre-sustained status
Needs More Attention
Real-time data needs, assimilation & analysis
Outward Focus
Provide program information (COD lead)
Develop data management roadmap to long-term goal of improving search and accessibility, bringing some consistency across data systems
Increase ties between global ocean observing system and communities developing observing capabilities for coasts, polar areas, living marine resources, and other locations and communities where climate impacts are acute and evident and where global ocean observations are useful
Data assimilation and analyis funding is down 1/3 since Fy09…. May be able to leverage other programs 35

36. Highlights www.oco.noaa.gov
Observations & Monitoring Program Revised OCO Web Site
Public, but not announced Announce publicly at end of July.
Contents include:
About our Program
Why We Observe
How We Observe
Observing Products
Ocean Climate Data
Education and Outreach
Feedback Welcome!
PIs: Review project summaries, feedback to Joel Levy 36

37. Congratulations on success of observing activities to date
Observations & Monitoring Program Summary
Congratulations on success of observing activities to date
Many compelling reasons to continue observing; and opportunities will present themselves to expand and improve the program (be prepared!)
Thank you for your personal and institutional support of the program.

38. Thanks all and the COD Team
Highlights
Observations & Monitoring Program
Thanks all and the COD Team

41. Observations & Monitoring Program FY11 Highlights – XBT/AMOC
Scatter plot of the strength of the AMOC vs total Meridional Heat Transport across 34S. Dots and circles correspond to Earth Simulator (OFES) model and XBT observations, respectively. The black and gray lines indicate the regression of the heat transport to the AMOC from OFES and XBT observations, respectively.
We are using XBT heat transport estimates to verify the output from numerical models.
Shown here is the regression between heat transport and the meridional overturing circulation along 35S (AX18) from the model and observations. The model used is the output from the ocean general circulation model for the Earth Simulator (OFES) during the period 1980–2006 (Dong et al 2011a). The meridional heat transport from OFES shows a similar response to AMOC variations to that derived from XBT observations: a 1 Sv (1 Sv =106 m3 s-1]) increase in the AMOC strength would cause a / PW increase in MHT at approximately 34S (Figure 4).
Once validated, the model can be examined to look at the processes that are important in setting heat transport varaiblity.
The Dong et al 2011 paper also shows (not shown) the main feature in the AMOC and MHT across 34S is their increasing trends during the period 1980–93. Separating the transports into boundary currents and ocean interior regions indicates that the increase in transport comes from the ocean interior region, suggesting that it is important to monitor the ocean interior region to capture changes in the AMOC and MHT on decadal to longer time scales. The linear increase in the MHT from 1980 to 1993 is due to the increase in advective heat converged into the South Atlantic from the Pacific and Indian Oceans. Of the total increase in the heat convergence, about two-thirds is contributed by the Indian Ocean through the Agulhas Current system, suggesting that the warm-water route from the Indian Ocean plays a more important role in the northward-flowing water in the upper branch of the AMOC at 34S during the study period.
Dong et al 2011
Increase in the AMOC strength would cause a / PW increase in MHT at approximately 34S 41