INFLUENCE OF ATMOSPHERIC TELECONNECTION PATTERNS ON PRECIPITATION AND UPWELLING M. Gómez- Gesteira 1 *, M. deCastro 1, I. Alvarez 1, M.N. Lorenzo 1, A.J.C. Crespo and J.J Taboada 2 1 Grupo de Física de la Atmósfera y del Océano, Universidad de Vigo, Ourense, Spain 2 METEOGALICIA *
Miño River Area under Scope N 42.5 N 43 N 43.5 N 44 N Galicia Iberian Peninsula Ekman Transport Ekman Transport Ekman Transport Ekman Transport Ekman Transport Ekman Transport Miño River
Rain- Gauge Station Mean Precipitación DJF (mm) FONSAGRADA (FONS) MONTEDERRAMO (MONT) FOLGOSO DE CAUREL (FOLC) VAO (VAO) O BOLO (BOLO) MONFORTE DE LEMOS 'E.AGRICOLA' (MOF1) CASTRO DE REI (CREI) SAN ESTEBAN (SEST) AIRA PADRON (AIRP) PUEBLA DE BROLLON (PDBR) SEOANE DO COUREL (SEOC) VEIGA DE BRAÑAS (VEIB) SEQUEIROS (SEQU) ACIVEIROS (ACIV) TRIVES 'SAN JUAN DEL RIO' (TRIV) PARAMOS-GUILLAREI (PAGU) ORENSE 'GRANJA DIPUTACION' (OURE) MONFORTE 'A PINGUELA' (MOF2) PUEBLA DE BROLLON 'VEIGA' (PDBV) SARRIA 'GRANXA BARREIROS' (SARR) ALLARIZ (ALLA) LUGO 'COLEGIO FINGOI' (LUGO) Frieira Precipitation and Miño River discharge M. deCastro et al., Climate Research 32 (2006)
Mean monthly flow (Miño River) (Data from October 1970 to September 2005) OctNovDecJanFebMarAprMayJunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSep
Normalized precipitation DJF (blue) y and river discharge (red) (Data from 1976 to 1997) C.C.=0.88
Correlation between modes and river discharge Lead (months) IndexCorrelation NAO-0.54 (2) SCAND0.63 (1) EA/WR-0.46 (1) EA0.40 (0)
Evolution of the correlation between modes and river discharge Running period (22 years)
Variability of Upwelling Conditions In Western Iberian Peninsula: UI = -Qx Qx < 0 upwelling favorable Qx > 0 upwelling unfavorable Zonal Ekman transport Data
Upwelling Conditions Days per month under upwelling favorable conditions
Atmospheric patterns vs Q x during the wet season (NDJF) M. deCastro et al., Jornal Marine Systems 72 (2008) *** significance level > 95% Correlation between atmospheric modes and Qx from 1966 to EANAOEA/WRPOLSCAND Q x (NDJF)0.65 ***
EA Pattern Evolution EA > 0 associated to southerly winds at Galician shelf Positive values from 1983 on, which result in upwelling unfavorable conditions Q x Anomaly Evolution
SLP composites
Atmospheric patterns vs summer UI SST M. deCastro et al., Climate Research 36 (2008)
Atmospheric patterns vs UI SST
Precipitation/river discharge depend on several indices (NAO, SCAND, EA/WR, EA) The dependences is not stationary Summary: Winter upwelling in Galician region depends on EA Winter upwelling tends to decrease during the last decades Summer upwelling depends on EA and NAO along the Western Iberian Coast Dependence on NAO decreases northward
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DatesUIAM (ºC)EA Sep Sep Aug Aug Sep Oct Aug Aug Sep
NAO and EA. Map of Correlations with precipitation departures Dry winter in Galicia NAO with a positive phase Above- average precipitation during winter in Galicia EA with a positive phase DJF average
Correlación Modos vs. Precipitación DEF coeficientes invernales de correlación de los distintos índices de teleconexión y la precipitación de las estaciones situadas (Octubre Septiembre 1997)
Correlación Modos vs. Precipitación Variación interanual de los modos promediados a DEF (línea roja) y las precipitaciones (línea azul) (Octubre 1976-Septiembre 1997)