TACE : Tropical Atlantic Climate Experiment

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TACE Tropical Atlantic Climate Experiment
Endorsed by CLIVAR SSG14 http//www.clivar.org/org
anization/atlantic/TACE/tace.php
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TACE motivation SST bias coupled models
SST bias in IPCC 4AR models
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TACE motivation lack of predictive skill
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TACE motivation relative lack of observations
(improving)
March 2005
March 2004
April 2006
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TACE motivationZonal mode bias in coupled models
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• TACE Goal
• to advance the understanding of coupled
  ocean-atmosphere processes and improve climate
  prediction for the Tropical Atlantic region
• Enhance existing observing system to provide the
  data needed for research and operations (Obs WG).
• Improve coupled predictive systems, ocean
  synthesis, and transfer from science to
  operations (ModelSynth WG).
• TACE is planned as 6 year (2007-2012) enhanced
  monitoring study, ultimately leading to
  specification of the sustained observations
  network in the tropical Atlantic needed to meet
  CLIVAR goals
• Connects with VACS, VAMOS, WGSIP, WGOMD, and
  PIRATA
• PIRATA observational backbone of TACE TACE is
  an enhancing observational network temporarily

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OBS WG main activities

• Coordination and tracking of various
  international contributions to the envisioned
  TACE observational strategy.
• Promotion of collaboration between various
  observational groups to maximize opportunities
  for shared use of observational platforms and
  efficient deployment of observing system
  components.
• Identification of gaps in the observing system
  and evaluation of possible means to implement the
  required enhancements.
• Monitoring of data availability and usage by the
  climate user community.

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TACE working group on observations

• Chair Peter Brandt(IFM-GEOMAR, Kiel, Germany)
• Vice Chair William E. Johns(RSMAS, Miami, U.S.)
• Bernard Bourlès(IRD, Plouzané, France)
• Marcus Dengler(IFM-GEOMAR, Kiel, Germany)
• Gustavo Goni(NOAA/AOML, Miami, U.S.)
• Rick Lumpkin(NOAA/AOML, Miami, U.S.)
• Chris Reason(University of Cape Town,South
  Africa)
• Mathieu Rouault(University of Cape Town,South
  Africa)

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http//tace.ifm-geomar.de/index.html

• Projects and programs AMMA, BMBF, CORIOLIS, DFG,
  EGEE, EQUALANT, PIRATA, RSMAS-project,..

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Ship cruises - performed
Glider transects
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Island meteorological, Flux and Tide Gauge
Stations
XBT Lines
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Simultaneous oceanic cruises in May-July
2006(carried out in the framework of AMMA,
PIRATA CLIVAR)
1) FRENCH ATALANTE / EGEE 3 cruise (East of the
basin) May 24 July 6, 2006 2) GERMAN METEOR
cruise (West and central basin) May 23 July
16, 2006 3) US RON BROWN cruise (North and
central basin) June 6 July 9, 2006
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2
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PIRATA 12 Meeting, Miami, November 1-3, 2006
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AMMA African Monsoon Multidisciplinary Analyses
EGEE program gt 6 cruises, 2 per year in 2005,
2006 2007 ? interannual variability (Egée 1-gt6)
intra-annual (Egée 3)
Egée 1 trackline (June-July 2005) Egée 2
trackline (Sept. 2005)

• Repeated sections at 10W and 3E.
• continuous SST, SSS, surface currents
  measurements, meteorological measurements
• CTD-02 profiles and current profiles (0.5)
  temperature profiles (XBT) every 0.5 or 1
• oceanic turbulence (MSS Dengler at IFM-GEOMAR)
  
• water samplings (CO2, O18 C13, nutrients,
  Helium Rhein at Univ. Bremen)
• ARGO profilers NOAA/GDC surface drifters
  deployment (SVP)

TACE workshop, Paris- Unesco, Nov 18-20, 2006
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Next planed cruises

• EGEE 4 Nov,15 Dec,2, 2006 (Dakar-Cotonou)
• EGEE 5 June 2007 ? PIRATA 16
• EGEE 6 September 2007
• TACE moorings deployment (B.Johns)
• (cruise trackline to be adapted, 10W 3E
  sections have to be done)
• yearly PIRATA cruises
• GLIDER in the Gulf of Guinea (IRD/LEGOS
  project) ?
• (from Cotonou to Equator Sao Tome)

All cruises planed on board the IRD R/V ANTEA
(tests during EGEE 4).
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Links with TACE (Tropical Atlantic Climate
Experiment from 2007)

• Summary of french potential contribution  on the
  field  during TACE
• EGEE (2007) and PIRATA (2008-?...) cruises
• (possible SouthEastern extension servicing if
  maintained)
• (gt CTD, ADCP, XBT, ARGO, TSgraph meteo)
• Meteorological Station (GTS transmitted) tide
  gauge at Sao Tome (yearly servicing)
• 23W 10W -Equator surface ADCP moorings
• coastal SST (Sao Tome, Benin, Togo, ) data
  available about every 3-6 months
• Glider (from 2008/2009 ?)

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Equatorial Circulation in the central TA
Project funded by German Research Ministry
2006-2009 (Brandt et al.)

• Ship Cruises
• in June 2006 (first deployment of mooring array
  at 23W)
• in April 2008
• in autumn 2009

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Mooring array at 23W
Observation of the eastward thermocline transport
at the equator 3 moorings at 23W 0.75N, 0N,
0.75S (including PIRATA ADCP)
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Mooring array at 23W
2 additional moorings will be deployed in April
2008 at 2N/S Glider section along 23W
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Mooring Array in the Eastern TA (B. Johns, RSMAS)

• Subsurface current meter moorings to observe
• EUC termination
• Equatorial wave guide in the eastern TA
• First deployment in 2007

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Oxygen minimum zone in the northern TA
Proposed new German Sonderforschungsbereich

• Moored CTD/O2 profilers at 23W, 5N (pilot
  deployment June 2006) and 23W, 8N
• profiles between 100 and 1000m (Brandt et al.)
• additional oxygen sensors, possibly added to
  existing PIRATA buoys at 23W
• tracer release experiment (Visbeck et al.)
• glider section along 23W including O2
  measurements

Planned Start January 2008
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Funded U.S. Moorings for extended EUC/cold tongue
Experiment
Summer 2009 Enhanced observation campaign for
cold tongue
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gt Large increase of T/S(z) data in the region
June 23, 2005 September 28, 2005
Map of the ARGO profilers in Tropical Atlantic,
late August 2006 (from CORIOLIS).
???
Green dots T S profiles / Blue dots T
profiles only.
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ModellingSynthesis WG

• The WG will contribute to the following issues
• Determine oceanic processes important in
  regulating SST in the tropical Atlantic and
  associated responses.
• Improve SST forecasts on seasonal to
  interannual time scales in the tropical Atlantic.
  
• Provide parameterizations and model
  improvements to global and regional prediction
  centers.
• Investigate response of tropical Atlantic
  region to global warming, including
  teleconnection patterns
• Improve the design and performance of the
  required ocean observing system.

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Variance of Northern Tropical Atlantic (grey) and
Eastern Equatorial Atlantic SST (black) in IPCC
4AR 20th century and SRES A1b runs (Breugem et al
2006)
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• WG set up, chaired by Markus Jochum (NCAR)
• WG is writing a white paper on modelling issues
  and strategy for the tropical Atlantic
• New emphasis on regional coupled modelling
• WG will meet at IUGG Perugia 2007
• IPCC 4AR variability synthesis, see
• http//www.knmi.nl/samenw/tameet/ipcc_ar4_comp