CLIVAR Atlantic perspective

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CLIVAR Atlantic perspective
Stuart Cunningham On behalf of the CLIVAR
Atlantic Implementation Panel
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CLIVAR Atlantic Implementation PanelTerms of
reference
To recommend and oversee the implementation of
observations in the Atlantic Ocean sector, in
order to meet the objectives outlined in CLIVAR's
Science and Initial Implementation Plans,
particularly with respect to the Principal
Research Areas D1 (North Atlantic
Oscillation), D2 (Tropical Atlantic Variability)
andD3 (Atlantic Thermohaline Circulation).
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CLIVAR Atlantic Implementation Panel
W. Hazeleger (co-Chair) KNMI, AE de Bilt, The
Netherland R. Curry (co-Chair) WHOI, USA P.
Brandt IfM-GEOMAR, Kiel, Germany S.
Cunningham NOCS, Southampton UK W. Johns
RSMAS, Miami, USA N. Koc NPI, Tromso
Norway Y. Kushnir LDEO Columbia University
USA P. Nobre CPTEC/INPE, São Paulo, Brazil S.
Oesterhus Uni. Bergen, Norway A. Piola SHN,
Buenos Aires, Argentina C. Reason University of
Cape Town, South Africa D. Stammer IfM, Uni.
Hamburg, Germany R. Sutton CGAM, Univ. of
Reading, UK L. Terray CERFACS, Toulouse
France Ex Officio Member A. Körtzinger
(Carbon) IfM-GEOMAR, Kiel, Germany ICPO
contact Dr. Roberta Boscolo
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CLIVAR Atlantic SectorPhenomena

• North Atlantic Oscillation
• Tropical Atlantic Variability
• Meridional Overturning in the Ocean
• With emphasis on interactions with each
  other and/or other climate forcings
  including ENSO and ACC

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CLIVAR Atlantic SectorStrategy

• Promote a balanced approach to describe,
  understand and assess predictability of climate
  phenomena using
• Observations (joined with OOPC and GSOP)
• sustained observations
• regionally enhanced observations
• process studied
• Modeling and Theory (joined with WGCM, WGOMD)
• global and region GCMs
• process models
• Synthesis (joined with GSOP and partly WGSIP)
• empirical studies
• atmosphere / ocean / (land) reanalysis
• Predictability / Predictions

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CLIVAR Atlantic Ocean Observing Network
Compiled by R. Boscolo - check CLIVAR website
for details
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Fixed Point Time-series
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Barent Sea - transport 1997-
Fram Strait - transport 1997-
Greenland Sea - Observatory 1999-
OWS M Norwegian Sea 1948-
Atlantic Inflow and Outflow Iceland-Faroe-Shetland
1999- and 1995-
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Denmark Strait - overflow 1997-
SE Greenland - transport 1987- 2003-
RAPID tracer - Observatory 2004-2007
Loco Moorings - Irminger Sea 2003-2008
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WHOI mooring - Irminger Sea 2002 - 2004 - 2008
OVIDE Moorings - Irminger Sea 1987- 2003-
RAPID Moorings - Cape Farewell 2005-2008
CIS - PAP - ESTOC Observatories 2003-
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Davis Strait - Transport 2004 - 2007
OWS B - Observatory 1960 - 2007 (lack of funding)
Labrador slope - moorings array 1977-92
/1995-operational
Flemmish Pass Orphan Basin - moorings 2002 -
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Labrador Sea Export 1999 - 2005
NADW Export 1999 - 2005
RAPID - WAVE array 2007- 2014
Station W- moorings 2004 - 2014
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K279 Azores Front - observatory 1980 -
BATS / Station S 1954 -
RAPID - 26.5 N 2004 - 2012
Florida transport - voltage measurements 1982 -
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MOCHA - DWBC transport 2004 - 2014
ABACO mooring timeseries 1986 - 97 / 2004-2014
Cape Verde Observatory 2006 -
NTAS Observatory 2001 -
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MOVE Array 2000 - 2007
PIRATA 1997-
2006
2007
VEMA Channel Observatory 2003 -
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Repeat Hydrography
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Low Density Frequently Repeated XBT Lines
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High Density XBT Lines
AX7 from 1995 AX10 from 1997 AX8 from 2000 AX18
from 2002 AX25 from 2004 AX97 from 2004
Thermosalingraph Lines
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Argo Floats
planning
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(No Transcript)
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Tropical Atlantic Climate ExperimentTACE(B.
Johns W. Hazeleger)
To advance understanding of coupled
ocean-atmosphere processes and improve climate
prediction for the Tropical Atlantic
region Specific goals are a) To advance
understanding of the key processes that control
SST, interactions with the AMI (Atl. Marine
ITCZ), and related climate predictability in the
eastern tropical Atlantic. b) To contribute to
the design of an enhanced sustained observing
system for the tropical Atlantic region.
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TACEModeling Strategy (B. Johns W. Hazeleger)
1) Determine oceanic processes important in
regulating SST in the tropical Atlantic and
associated atmospheric responses 2) Improve SST
forecasts on seasonal to interannual time scales
in the tropical Atlantic 3) Provide
parameterizations and model improvements to
global and regional prediction centers 4)
Investigate response of tropical Atlantic region
to global warming, including teleconnection
patterns
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Tropical Atlantic Observations
TACE Tropical Atlantic Climate Experiment TACE
core period six years 2006/7 - 2011/12
http//tace.ifm-geomar.de/index.html
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TACE Observations
TACE Tropical Atlantic Climate Experiment TACE
core period six years 2006/7 - 2011/12
http//tace.ifm-geomar.de/index.html
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WAVEs proposal -southWestern Atlantic climate
Variability Experiment

• Coupled o-a variability associated with SACZ
• SST-Solar Radiation-Rainfall feedback processes
• Barrier layers due to SACZ rainfall over the
  ocean and river discharges the importance of
  solar radiation diurnal cycle
• South America Monsoon System soil
  moisture-biosphere rainfall memory ITCZ-SACZ-LLJ
  interactions?
• Teleconnections from other ocean basins
• SW tropical Atlantic oceanic circulation
• Density anomaly (T-S) advection by the SEC
• SEC bifurcation
• MOC-STC pathways
• Brazil-Malvinas confluence zone
• Sea level in situ and satellite estimates
• Other phenomena
• South Atlantic Subtropical High pressure
  variability and climate fluctuations over South
  America and southern Africa.
• Transport of continental aerosols (from
  S.America) over the South Atl.
• Oceanic dissolved CO2,

February, 2007
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Direct Measurements of MOC at 26.5 N

• Cunningham et al. 2007

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FreshWater storage

• Curry et al. 2007

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Atlantic Meridional Heat Flux at 35S
Speich et al 2007
Record length mean annual cycle of meridional
heat flux from gECCO (in blue, Köhl et al., JPO,
2007) and from the 14 transatlantic XBT sections
(blueEkman, red squaresgeostrophic, red
diamondstotal, Garzoli Barringer, DSR, 2007).
The negative relation between Ekman and
geostrophic changes supresses the seasonal
variations of the total heat flux in the point
estimates.
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Emerging Decadal Predictions
Outstanding issues Initialization Perturbation Ve
rification Drift
D. Smith et al 2007
CLIVAR observational requirements and synthesis
for decadal predictions Ocean analysis for
initialization with error estimates
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Strength of Tropical Atlantic Variability and its
Future Change
Breugem et al 2007
zonal mode
meridional mode
Ruiz Baradas et al
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Faroe-Bank Channel overflow
Science paper was written
No trend ! but the time series is short
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Labrador Sea Exit Moorings Germany
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Labrador Sea Exit Moorings Canada
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Deep Water Export Grand Banks
Schott and Fischer (2006)
Stable flow speed over the last 12 years
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CLIVAR Atlantic Implementation Panel GSOP/OOPC
actions

• Sustained Observations in support of decadal
  (ocean) signals
• MOC
• Overflow measurements (Denmark Strait, FS
  Channel)
• Boundary currents (transport, water masses)-
  Labrador Sea outflow- 26N RAPID/MOCHA cable-
  NADW deep eddies (design research) ?- 20-30S
  (design research) ?
• Potential Energy time series- Labrador Sea-
  Bermuda- Irminger Sea (research)- Porcupine
  Bank (research)- Cape Verde (research)
• Tropical Atlantic Variability
• PIRATA Extensions/replacements (research)
• TACE (enhanced surface drifter ARGO PIRATA)

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CLIVAR - OOPC/GSOP Issues

• How to maintain existing networks?- CLIVAR is
  one of the scientific users of the existing
  networks. But all the users should speak with one
  voice when it comes to defend observing systems.
  Will OOPC/GSOP be the voice with input from
  CLIVAR when needed? - How to evaluate the
  overall usefulness of a particular observing
  system in the context of other data and a variety
  of users?
• - CLIVAR has pilot projects in the water that,
  if proven useful, should be sustained. How will
  we accomplish that? (list to come).
• Rich mixture of data types (state, flux)
  (shallow/deep)- How to come to global/regional
  synthesis- How to manage data

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CLIVAR - OOPC/GSOP Issues

• Developed metrics for evaluation (predictions,
  AMOC state etc)-http//www.clivar.org/organizati
  on/atlantic/Metrics/ATL_metrics.pdf
• Provide synthesis data and metadata for decadal
  prediction