centro internacional para la investigación del fenómeno de el niño i foro de perspectivas...
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Centro Internacional para la Investigación del Fenómeno de El Niño
I FORO DE PERSPECTIVAS CLIMÁTICAS PARA SUDAMÉRICAGuayaquil - Ecuador, 01 al 04 de Octubre 2012
Seminario - Taller Clima de Sud América
Cambio Climático en SA: Observaciones y Proyecciones
Relator: Dr. René D. Garreaudwww.dgf.uchile.cl/rene
Departamento de GeofísicaUniversidad de Chile
Is the regional cooling of theHumboldt EBUS already taking place?
Over the Pacifc SST trend looks very similar to the PDV patter
2006-1979
Falvey & Garreaud 2007
Is th
e re
gion
al c
oolin
g of
the
Hum
bold
t EBU
S al
read
y ta
king
pla
ce?
offshore
coast
inland
WestAndes
East Andes
Falvey & Garreaud 2007
Trends in°C/décade (1984 – 2010), from Trends in°C/décade (1984 – 2010), from Reynolds data base (1/4° resolution) Reynolds data base (1/4° resolution) (Gutiérrez et al., RPGA, subm.)(Gutiérrez et al., RPGA, subm.)
Callao
PiscoSan Juan
Ilo
13
14
15
16
17
18
19
pee
rs S
ST
(ºC
)
15
16
17
18
19
20
1950 1960 1970 1980 1990 2000 2010
14
15
16
17
18
19
20
18
19
20
21
22
23
24
Callao (12°S)y =57.8 - 0.021 y -1
p<0.05
Pisco (13.8°S)
San Juan (15.5°S)y = 86.0 - 0.036y-1
p<0.1
Ilo (17°S)y = 47.0 - 0.016 y-1
p<0.05
y = 102.3 - 0.041y-1
p<0.001
Gutiérrez, Bouloubassi, et al., GRL, to be submitted
Is th
e re
gion
al c
oolin
g of
the
Hum
bold
t EBU
S al
read
y ta
king
pla
ce?
Temperature trends 1979-2006
Falvey & Garreaud 2007
How are the models doing?Not good but no so bad..
T/toff Central Chile
T/tcentral Andes
Multimodel mean Regional warming 1970-2000 (SST*). Also shown in contours SLP* trend
Global mean: +0.2º/dec
TENDENCIA DE LA PRECIPITACION ANUAL - 1950-2000
-200
-150
-100
-50
0
50
100
1503
0
32
33
34
35
37
38
39
40
42
45
53
Latitud Sur
mm
/10
añ
os
Ref.: Quintana, 2004
• Semiarid climate• MAP 30-500 mm• (IA)/MAP 0.3 – 0.5• Strong ENSO Impact• No significant trend
Precipitation Changes….warming, drying south
• Rainy climate• MAP 1000-3000 mm• (IA)/MAP 0.1• Weak ENSO Impact• Significant drying trend
Central Chile (30-35ºS)
Southern Chile (38º-41ºS)
Year
Norm
aliz
ed
rain
fall
Norm
aliz
ed
rain
fall
Evolu
ción d
e las
Pre
cip
itaci
on
es
Tendencias observadas de precipitación: ¿?
Retro-alimentación del sistema climáticocambian la respuesta al incremento del CO2
Ruddiman: Earth’s Climate, Chapter 4
Parte “facil”Calculo radiativo…
Future Climate ScenariosGHG (CO2,…) emissions projections + GCMs
20+ GCMsCMIP3/IPCC AR4
© IPCC 2007: WG1-AR4 (2007)
© IPCC 2007: WG1-AR4 (2007)
© IPCC 2007: WG1-AR4 (2007)
Zonal mean distribution of temperature change (2xC02-Ctr)
© IPCC 2007: WG1-AR4 (2007)
Multimodel average SLP difference betweenA2 (2070-2100) and BL (1970-2000)
Strengthening of the poleward flank of subtropical anticyclones and poleward shift of the midlatitude storm track is very consistent among GCMs
Annual mean
Garreaud & Falvey 2007
Multimodel average SLP and sfc wind difference betweenA2 (2070-2100) and BL (1970-2000)
Over open ocean v in geostrophic balance with SLP.Near the coast v more controlled by along-coast SLP
Annual mean
Garreaud & Falvey 2007
2 month extended upwelling season(earlier onset, later demise)
Stronger southerlies
PRECIS Results
Garreaud & Falvey 2007
Las Cruces
Lavapie
QuikScat data (2000-2006)PRECIS BL (1961-1990)PRECIS A2 (2071-2100)
Frequency of surface meridional wind speed at 33°S 74°W
PRECIS Results
Garreaud & Falvey 2007
More frequent /extended episodes ofstrong southerlies
Less downwellingfavourable wind
PRECIS Results
-1° 0° 1° 2° 3° 4° 5° C
Differences A2(2100-2070) – BL(1960-1990)Obtained with a regional climate model (PRECIS) forced by HadCM3 / A2
-50 0 +50 mm/mes
Temperatura Superficial (SAT) Precipitación (P)
PRECIS-DGF-UCH
Urrutia and Vuille 2009
Diferencia T2m (2100-2070) – (1960-1990)Obtained with a regional climate model (PRECIS) forced by Echam4 / A2
B2-LB A2-LB
Diferencia Pp A2(2100-2070) – BL(1960-1990)Obtained with a regional climate model (PRECIS) forced by Echam4 / A2
dP (mm/año) dP/Pbl (%)
Urrutia and Vuille 2009
Multimodel mean diff. A2-BLin 200 hPa wind, summer
Multimodel mean diff. A2-BLin zonal wind along 70°W
summer
Cambios de Circulación A2- BL
Minvielle and Garreaud 2010
Cambios de Precipitación esperables por cambio de viento
Minvielle and Garreaud 2010
dP (mm) dP/Pbl (%)