Air-Sea Interactions
in the SAMS Region
Paulo Nobre
CPTEC/INPE
III Reunião de Análise e Previsão Climática do PMTCRH
para o Nordeste do Brasil em 2005.
Recife, 17 de março de 2005.
SAMS CLIMATE VARIABILITY &
CONVERGENCE ZONES
From: Grodsky and Carton (2002)
Seasonal Precipitation Anomaly Correlation
CPTEC AGCM simulation and CAMS precip.
DJF
MAM
From: Marengo et al. (2002)
Nordeste’s Rainfall Predictability
personal com.
L. Marx
COLA
The Atlantic ITCZ
(A)
DRY
A
200N
WARMER SST
ITCZ
00
COOLER SST
A
200S
Meridional
Gradient
SSTA
WET
(B)
A
200N
COOLER SST
00
ITCZ
WARMER SST
200S
A
800W
600W
400W
200W
00
200E
Adapted from: C. A. Nobre and L. C. B. Molion (1988)
ATLANTIC ITCZ POSITION AND OLR
ANOMALY CORRELATION
MAM CPTEC AGCM T062L28
ANOMALY CORRELATION
TAUY
RAINFALL
South Atlantic Convergence Zone
& SSTA
Prescribed SST anomaly fields
COLD
WARM
Nobre et al. (2002)
Nobre et al. (2002)
Nobre et al. (2002)
SST DIFFERENCES:
OGCM EXPERIMENTS
Warm-Ctrl: Wind + SW
Cold-Ctrl: Wind + SW
Chaves and Nobre (2004)
CPTEC CGCM SISTEMATIC ERRORS
DFJ Precip Anomaly Correlation
AGCM SIMULATIONS
CGCM PREDICTIONS (October IC)
CPTEC CGCM – AGCM
DFJ PRECIP ACOR
Observations: The PIRATA Array
R/V ANTARES
The PIRATA BACKBONE
and the SW EXTENSION
(INMET-2004)
(LAMEPE-2002)
To be moored by July 2005.
Background map: Mean No. of SST observations/month COADS 1961-90
PIRATA SWE &
JASON/T-P ground tracks
ITCZ Sounding Experiment-2006
CTD Stations
SPSP
Fortaleza
F. Noronha
Natal
Final Remarks
• Convergence zones represent important
mechanisms modulating precipitation variability
over South America.
• ITCZ: planetary scale, strongly modulated by SST:
– Prediction of SSTA over the tropical (South) Atlantic.
• SACZ: Regional scale, coupled phenomena:
– 1-Tear approach is a need.
• Needs:
–
–
–
–
Coupled model development (eastern basin St. deck),
Coupled data assimilation,
Ensemble prediction techniques,
Sustained ocean observation strategies (e.g. PIRATA)…