1) The AMMA programme 2) The PIRATA programme 3) in situ observations in the Eastern Tropical Atlantic : status and prospectives

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1 1) The AMMA programme 2) The PIRATA programme 3) in situ observations in the Eastern Tropical Atlantic : status and prospectives Bernard BOURLES (IRD - Institut de Recherche pour le Développement -, France) Member of the AMMA ISSC / Coordinator of EGEE (ocean and climate studies in the Gulf of Guinea in the framework of AMMA) Co-Chair of the PIRATA ISSC & member of the CLIVAR-Atlantic Panel Centre IRD de Bretagne, Technopole Pointe du Diable, B.P. 70, PLOUZANE, FRANCE Tél.: ; from abroad: Fax: ; from abroad: Tél. portable: courriel: Bernard.Bourles@ird.fr ou bbourles@ifremer.fr

2 1: African Monsoon Multidisciplinary Analyses Afrikanske Monsun: Multidisiplinære Analyser Afrikaanse Moesson Multidisciplinaire Analyse Analisi Multidisciplinare per il Monsone Africano Afrikanischer Monsun: Multidisziplinäre Analysen Analisis Multidiciplinar de los Monzones Africanos Analyses Multidisciplinaires de la Mousson Africaine

3 Why AMMA? Annual rainfall & runoff deficit Niger at Malanville: km² Factor 2

4 Why AMMA? How well do GCMs simulate the annual cycle? African Monsoon not well reproduced & predicted by the atmospheric numerical models => model failure : Numerical model Observations GCMs tend to have an early rainfall onset + higher precipitation than really observed the land surface conditions (e.g., Taylor and Lebel 1998) the atmospheric circulation (e.g., Roca et al. 2005) - SST variability (ocean) (e.g., Okumura and Xie 2004) - Air sea fluxes (e.g., Okumura and Xie 2004) Observed and modeled rainfall (with labels for onset and retreat) for Niamey based on area-average of 50 gauges and model simulated rainfall ( Lebel et al, 2000).

5 AMMA African Monsoon Multidisciplinary Analyses What is AMMA? 1. Context: AMMA is a coordinated international project to improve our knowledge and understanding of the West African monsoon (WAM) and its variability with an emphasis on daily-to-interanual timescales 2. A coordinated international effort: Scientists from more than 25 agencies/institutions in more than 20 countries in Africa, Europe and US (Algeria, Benin, Burkina Faso, Cameroon, Chad, Denmark, France, Germany, Ghana, Italy, Ivory Coast, Mali, Niger, Nigeria, Senegal, Spain, Togo, UK, US ) Endorsements received from CLIVAR & GEWEX, GCOS, Funding by France, European Union, USA and United Kingdom (>10M each)

6 AMMA African Monsoon Multidisciplinary Analyses What is AMMA? 3. A multidisciplinary and multiscale approach: Global: 2-way interactions between the WAM & the rest of the globe (e.g. role of SST patterns on WAM variability; impact of WAM on tropical Atlantic, export of aerosols/chemical species). Variability from seasonal to decadal scales Regional: Monsoon Dynamics and Scale Interactions, Continental Water Cycle, Land and Ocean Processes, Aerosols and Chemistry Variability from intraseasonal to interannual scales Mesoscale: Mesoscale Convective Systems, Vertical transports (Aerosols, Water, chemical species), Tropical Cyclones, Catchments and Vegetation Intraseasonal variability Sub-meso (<10km): Hydrological Cycle, Vegetation Convective rain scale=>coupling scale with hydrology (Sahel)=>Main scale of interest for agriculture, M O D E L L I N G S A T E L L I T E S O B S E R V A T I O N S

7 AMMA African Monsoon Multidisciplinary Analyses What is AMMA? 4. Human dimension: Impact studies : Water resources Health impacts Land productivity Human processes and food security

8 SPACE (km) Supra-regional (WA + Ocean) Regional (WA) What is AMMA? International Field Program : Long term Observation Period Enhanced Obs. Period Catch, Idaf, Aeronet Impetus, Pirata,. SOP0: Dry phase Mesoscale SO P SOP1: Monsoon Onset SOP2: Monsoon Max SOP3: Late Monsoon 10 1 Local IOPs IOPs IOPs TIME ( Years)

9 AMMA: Observation network in West Africa (key period, June-August 2006) Dakar Niamey Djougou Transects by instrumented aircrafts : «operationnal» radars [ + IDAF, AERONET networks]

10 AMMA African Monsoon Multidisciplinary Analyses Informations : - AMMA international Web site : - AMMA Africa Web site: - AMMA international Data Base (limited access at now) : ftp site through

11 Main International Contacts: Co-chairs of AMMA International Scientific Steering Committee: - Jean-Luc Redelsperger: jean-luc.redelsperger@meteo.fr - Chris Thorncroft: chris@atmos.albany.edu In Africa: Cherif Diop : Abou Amani : Leykan Oyebande : Arona Diedhou : In Europe: Jean-Luc Redelsperger : Doug Parker: Thierry Lebel : Andreas Fink : In USA: Chris Thorncroft : Peter Lamb: Cherifdiop@hotmail.com Amani@sahel.agrhymet.ne Lekanoye@hotmail.com diedhiou@ird.ne Redels@meteo.fr Doug@lec.leeds.ac.uk Thierry.Lebel@hmg.inpg.fr af@meteo.uni-koeln.de Chris@atmos.albany.edu plamb@ou.edu

12 2: PIRATA (Pilot Research moored Array in the Tropical Atlantic) ( ??) Tripartite Programme as a contribution to CLIVAR, GCOS and GOOS : - FRANCE (IRD & Météo-France) - BRAZIL (INPE & DHN) - USA (NOAA/PMEL & AOML) * : «Pilote» period * : Consolidation period : continuation and after!? (PIRATA has actually been under review process (positive ) by CLIVAR and Ocean Observations Panel for Climate -OOPC-) in 2006 Photo: A.Kartavtseff

13 PIRATA evolution until now PIRATA ATLAS buoys network in October 2005 (Brazilian SW extension => 13 buoys) First PIRATA ATLAS buoys network in 1997 (12 then 10 buoys) PIRATA ATLAS buoys network from June 2006 US NorthEast extension along 23 W at 4 N and 11 N (carried out by NOAA, R/V Ron Brown in June 2006) BCLME & South Africa SouthEast extension at 6 S-8 E (carried out by IRD, R/V L Atalante in June 2006) 16 ATLAS buoys actually operationnal 18 planed in 2007 (two added along 20 N by US)

14 PIRATA ATLAS buoys: Measured Parameters : Atmosphere: - wind (direction, speed) - relative humidity - air temperature - precipitation - incident radiation Ocean: - temperature (11 levels from surface to 500m) - salinity (4 levels; 0,20,40,120m) - pressure (at 300 & 500m) - Daily averaged data transmitted in real time by Argos; - High frequency data (10mn) available after servicing operations

15 Examples of PIRATA time series S-10 W 6 S-10 W wind Dyn.height T section Eq-0 E NEW 6 S-8 E

16 4) CO2 sensor installed at 6 S-10 W in June 2006 : The buoy has been sending CO 2 and O 2 data in real-time using ARGOS transmission since the 6 th of June By the end of June, the upwelling impact was clearly visible with fco 2 going up to 400 matm. A second one will be installed in 2007 in the west (4 N-38 W) PI: Nathalie Lefevre, IRD/LOCEAN info on the web page :

17 Main International Contacts: Members of the PIRATA International Scientific Steering Committee (at now ): Co-chairs: - Bernard Bourlès (IRD, France): bernard.bourles@ird.fr (resp.pirata France) - Edmo Campos (USP, Brazil): edmo@usp.br Vice-chair: - Rick Lumpkin (NOAA, USA): Rick.Lumpkin@noaa.gov (resp. PIRATA US) & - Paulo Nobre (CPTEC, Brazil): pnobre@cptec.inpe.br (resp. PIRATA Brazil) - Mike McPhaden (NOAA, USA): Michael.J.Mcphaden@noaa.gov - Fabrice Hernandez (IRD, France): fabrice.hernandez@mercator-ocean.fr - Serge Planton (Météo-France): Serge.Planton@meteo.fr Informations and data (free access) : Web sites:

18 OCEANIC STUDIES: Framework: AMMA/EGEE, PIRATA & CLIVAR/TACE EGEE = Etude de la circulation océanique et du climat dans le Golfe de GuinEE = French Ocean and Air Sea interactions component of AMMA Key Objectives Quantify the heat budget of the oceanic mixed layer (SST, air-sea fluxes, salinity) Gain a quantitative picture of the circulation in the tropical Atlantic Identify pathways within the Shallow Subtropical Cell Evaluate the quality of general circulation and mixed layer simulations against observations => improve understanding of underlying dynamics responsible for SST& mixed layer variability, air-sea exchanges. and then numerical simulations

19 Example: 2005 / 2006 SST comparison in the Gulf of Guinea (TMI): June 10, 2005 June 10, 2006 With strong links with African Monsoon variability => why, how, & consequences on regional climate, environment & ressources??? (atmosphere / ocean interactions, equatorial upwelling / cold tongue )

20 AMMA African Monsoon Multidisciplinary Analyses EGEE program : => 6 cruises, 2 per year in 2005, 2006 & 2007 variability: interannual (3 years) + seasonal (2 per year) + intra-annual (Egée 3) Cruises already carried out: - Egée 1 (June-July 2005) - Egée 2 (Sept. 2005) - Egee 3 (May-July 2006) - Egee 4 (November-December 2006) Scheduled cruises: - Egee 5 & 6 in 2007 (June & September) => Repeated sections at 10 W and 3 E. -continuous SST, SSS, surface currents measurements, meteorological measurements - CTD-02, turbulence and current profiles + temperature profiles (XBT) every ½ or ¼ - water samplings (Salinity, Oxygen, CO2, O18 & C13, nutrients, + Helium) + ARGO profilers deployment & NOAA/GDC surface drifters deployment (SVP)

21 AMMA African Monsoon Multidisciplinary Analyses e.g. EGEE 3 cruise (Gulf of Guinea) : May 24 July 6, ATLAS PIRATA deployement / replacing Stations CTD 4 o N XBT XCTD 72 CTD/LADCP profiles (red points) 106 ocean turbulence profiles (MSS) (red points) 0 o 180 XBT a XCTD profiles (green points) 12 ARGO profilers deployment 4 o S 8 o S PIRATA mooring 12 o S 15 o W 10 o W 5 o W 0 o 5 o E 10 o E 15 o E 13 SVP drifters deployment 12 thermistance profilers Radiosoundings (2 per day min => 101)

22 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, ) GERMAN METEOR cruise (West and central basin) : May 23 July 16, ) US RON BROWN cruise (North and central basin) : June 6 July 9,

23 Oceanic cruises in May-July 2006 Real time data: During the three quasi-simultaneous cruises: a) radiosounding profiles have been transmitted in real time by GTS (=> ECMWF ) b) temperature XBT profiles (0-800m) + temperature/salinity CTD profiles (0-500 or 1000m) have been transmitted in quasi-real time (at least daily) (also for CORIOLIS/ARGO and MERCATOR/GODAE projects). (radiosoudings at least twice a day from each vessel about 250 profiles) + ozone profiles from RonBrown (XBT profiles every ½ to 1 from Atalante and Ron Brown => about 250 profiles) (CTD profiles every ½ along meridional sections at 35 W, 23 W, 10 W, 3 E and 6 E => about 300 profiles)

24 + H.F. air-sea flux measurements from French and US cruises : e.g. on board the R.V L Atalante (EGEE 3) in the Gulf of Guinea Net radiation sensors classical meteorological parameters and turbulence sensors downward long and shortwave radiation sensors Skin SST t1 => atm. parameters (June 4-14) : changes from south to north of the equator t1 t2 Tair Tsea t3 Tsea-Tair t2 t3 Radiation equatorial upwelling RH + 6 long duration stations (24h min) => diurnal cycle Wind speed

25 Flux measurements in the Gulf of Guinea during EGEE 3 : 2 flights over the Gulf of Guinea, along 2 50 E, from the coast (Cotonou, 6 N) to 2 N: June 14th & July 4th (with RS every 3h) Bouressa 20 N CATCH Gourma 16 N -1,5 E Niamey 13.5 N ATR42 => turbulence & SST + in situ measurements Parakou 9.5 N F20 Léandre => 2 Lidar + dropsondes Djougou Cotonou 6.3 N Aircraft horizontal track Ground sites 2,5 E ATR42 as seen from Atalante 14/06/2006 8h GMT - 11h GMT Vessel stopped with flux measurements on July 4 => Both ocean & atm. boundary layers.

26 AMMA/EGEE & PIRATA contribution to ARGO: ARGO profilers deployment in the Eastern Atlantic and the Gulf of Guinea : Surface to 2000m depth T/S profiles every 10 days Data transmission through Argos 45 French PROVOR profilers deployed in US SOLO profilers deployed for NOAA in 2005 Mixed layer Example of temperature profiles provided by a PROVOR profiler over a two months period in the Gulf of Guinea. thermocline all data available on the CORIOLIS web site:

27 => Large increase of T/S(z) data in the region Map of the ARGO profilers in Tropical Atlantic, late August 2006 (CORIOLIS).? Green dots: T & S profiles / Blue dots: T profiles only.

28 TACE PIRATA EGEE/AMMA observing network

29 International Contacts: GERMANY: - Peter Brandt (IFM-GEOMAR, co-resp. TACE): Hydrology, currents - Marcus Dengler (IFM-GEOMAR): Ocean turbulence - Jurgen Fischer (IFM-GEOMAR): Hydrology, currents USA: - Bill Johns (RSMAS, USA, resp. TACE) Hydrology, currents - Erica Key (RSMAS, USA): Air-Sea fluxes - Rick Lumpkin (NOAA, USA): Hydrology, currents - Robert Molinari (NOAA, USA): Hydrology, currents FRANCE: - Bernard Bourlès (IRD, France): Hydrology, currents - Guy Caniaux (Météo-France): Air-Sea fluxes - Yves Gouriou (IRD, France): Hydrology, currents - Frédéric Marin (IRD, France): Hydrology, currents TACE informations : Web sites:

30 Other measurements carried out in the framework of EGEE / AMMA: Measurements at São Tomé Island (0 N, 6 E) Meteorological Station (EGEE) + Tide gauge (PIRATA) 1) Installation of a meteorological station in October 2003 (data transmitted dayly by ARGOS satellite system) - DATA TRANSMISSION THROUGH THE GTS (from October 2006) - Autonomous thermometer ONSET installed in 2005 (=> SST) 2) Tide gauge maintained by IRD since 1980s. - Pressure, Atm. pressure + SST & SSS. - Part of GLOOS. - GPS positioned (in December 2002)

31 Other measurements carried out in the framework of EGEE with African laboratories: 1) Coastal Sea Surface Temperature in the Gulf of Guinea GOAL: coastal upwelling and waves studies => Autonomous thermometers (Onset): ( three years duration, 1h period sampling) - Installed but interrupted in Ivory Coast ( ) - Installed in Bénin (from July 2005). Responsible: CRHOB - Installed in São Tomé -close to the meteorological station- (from September 2005) - Installed in Togo (from October, ). Responsible: CGIL/Univ. Lomé - and some efforts will be carried out in order to extend the installations in Nigeria, Ghana, and to proceed to re-deployment in Ivory Coast SST at Cotonou (09/18/05 12/28/05) hourly data. 30, , ,5 2) Training: 12 African scientists (Benin, Senegal, Ivory Coast, Nigeria, Ghana, Togo, Congo) contributed to the EGEE cruises (CTD, sampling, ARGO profilers deployment, XBT ) 28 27, ,5 26

32 Concluding remark - One of the main goals of AMMA is to make this international program dedicated to West African climate a way to reinforce the scientific research in African countries, => Implication of African teams for the AMMA observations network implementation (training and capacity building) and servicing => Training, summer schools, workshops, contribution to data exploitation For the ocean and climate scientific community, that important international programs as AMMA/EGEE, CLIVAR-TACE, PIRATA, ARGO + TENATSO&SOLAS are almost simultaneous is an unique opportunity to contribute to enhance oceanographic research in Africa and especially in Western Africa, => help for more implication of African teams in international ocean and climate programs => establish scientific links between large scale / open sea research and more local research (coastal studies, coastal upwellings, resources, erosion, sea level, ) Thank you