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PRECIPITATION ANOMALIES OVER SOUTH AMERICA IN THE SUMMER SEASON IN SCENARIOS OF CLIMATE CHANGE Iracema Fonseca de Albuquerque Cavalcanti. COLD AIR OUTBREAKS OVER SOUTHEASTERN SOUTH AMERICA IN THE WINTER SEASON IN SCENARIOS OF CLIMATE CHANGE Gabriela Müller Kelen Andrade
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PRECIPITATION ANOMALIES OVER SOUTH AMERICA IN THE SUMMER SEASONIN SCENARIOS OF CLIMATE CHANGEIracema Fonseca de Albuquerque Cavalcanti COLD AIR OUTBREAKS OVER SOUTHEASTERN SOUTH AMERICA IN THE WINTER SEASON IN SCENARIOS OF CLIMATE CHANGE Gabriela Müller Kelen Andrade Iracema FA Cavalcanti CENTRO DE PREVISÃO DE TEMPO E ESTUDOS CLIMÁTICOS INSTITUTO NACIONAL DE PESQUISAS ESPACIAIS
ANOMALOUS PRECIPITATION OVER SOUTH AMERICA • NATURAL CLIMATE VARIABILITY • ENSO CONDITIONS (EL NINO / LA NINA) • TELECONNECTIONS • INTRASEASONAL OSCILLATION • BEHAVIOUR OF SYNOPTIC SYSTEMS • BLOCKING SITUATIONS • ETC
DROUGHT IN 2005 DROUGHT IN 1997/1998 DROUGHT IN 2000/2001
THE QUESTION IS: WILL THE ANOMALIES CHANGE IN SCENARIOS OF CLIMATE CHANGE OVER SOUTH AMERICA? HOW THE INTENSITY OF NATURAL VARIABILITY CAN CHANGE IN THE FUTURE? MODELS
DJF PRECIPITATION CMAP/CAMS CPTEC/COLA AGCM
SOUTHEASTERN BRAZIL (50W-40W; 15-25S) Extreme wet years composite Extreme dry years composite
Extreme wet years composite Extreme dry years composite
IPCC-4 MODEL SIMULATIONS MODELS HADLEY HADCM3 GFDL HADGEN MRI ECHAM CANADIAN 20 CENTURYSRES A2 PRE-INDUSTRIAL 1% CO2 INCREASE
EXPERIMENTS Increase from CO2= 286.05 ppm at 1% /year rate to doubling, then constant to year 280. Other gases cte from 1860 1% CO2 EXPERIMENT High degree of global economic development (means high concentration of greenhouse gases) (2000-2100) SRES A2 Considers all anthropogenic forcings during the period of 1860 to 2000 (140 years) 20TH CENTURYEXPERIMENT Forcings agents representative of 1860 conditions constant. Include all greenhouses gases (280 years) PRE-INDUSTRIAL EXPERIMENT
PERIODS OF ANALYSIS • LAST 51 YEARS FROM EACH SIMULATION • DJF (S.H. SUMMER) • 20 CENTURY : 1949-1999 • SRES A2: 2048- 2098 OR 2049-2099
OBSERVED PRECIPITATION 20 CENTURY DJF 1979/1980 TO 1999/2000 MODELS SIMULATIONS MRI GFDL HADCM3
OBSERVED PRECIPITATION MODELS SIMULATIONS HADGEN ECHAM CANADIAN
PRE-INDUSTRIAL EXPERIMENT GFDL Difference between two periods in the pre-industrial experiment (year 71 to 280)- (year 11 to 70). The changes are very small, consistent with the absence of anthropogenic forcings.
ANNUAL GFDL DIFFERENCES BETWEEN 1%CO2 AND 20th century EXPERIMENTS GFDL DIFFERENCES BETWEEN 1%CO2 AND PRE-INDUSTRIAL EXPERIMENT GFDL The impact on precipitation is seen in the region of South Atlantic Convergence Zone and Southeastern South America considering the two experiments.
GFDL (USA) DIFFERENCES (FUTURE -20TH CENTURY) DJF 1%CO2 SRES A2
HADCM3 (UK) DIFFERENCES (FUTURE -20TH CENTURY) DJF 1%CO2 SRES A2
20 CENTURY GFDL LAST PERIOD 1% CO2 INCREASE 250 hPa 850 hPa
Difference between SRES A2 and 20th century wind flow HADLEY.
EXTREME MONTHLY PRECIPITATION ANOMALIES DJF • Average of precipitation anomalies over several areas of South America • 5 extreme years (+ and -) • 20th century and SRES A2 • Hadley and GFDL
AREAS W Amazonia E Amazonia N La Plata S La Plata
AREAS NE SE
PRECIPITATION ANOMALIES GFDL 20th century A2 ANOMALIES RELATED TO THE CLIMATOLOGY OF 20TH CENTURY AMAZONIA WESTERN SECTOR EASTERN SECTOR
LA PLATA NORTHERN SECTOR GFDL LA PLATA SOUTHERN SECTOR
GFDL PRECIPITATION ANOMALIES LA PLATA SOUTHERN SECTOR
GFDL NORTHEAST BRAZIL
A2 ANOMALIES HADLEY 20th century AMAZONIA WESTERN SECTOR EASTERN SECTOR
LA PLATA NORTHERN SECTOR LA PLATA SOUTHERN SECTOR
PRECIPITATION ANOMALY CORRELATIONS AREA 15S-25S; 40W-50W (SOUTHEAST) HADCM3 GFDL 20th century GFDL SRES A2 HADCM3
EXTREME PRECIPITATION ANOMALIES SOUTHEAST (50W-40W; 15S-25S) 20th century GFDL HADCM3 NEGATIVE ANOMALIES HADCM3 GFDL POSITIVE ANOMALIES
EXTREME PRECIPITATION ANOMALIES SOUTHEAST (50W-40W; 15S-25S)SRES A2 HADCM3 GFDL
COLD AIR OUTBREAKS OVER SOUTH AMERICA • CNPq colaboration project Argentina, Uruguay, Brazil. • Objective: Identify frequency and intensity of extreme cold air outbreaks in the present climate and in the future. • Will the global warming affect the frequency and intensity of the cold air outbreaks?
TEMPERATURE CHANGES (annual) GFDL 1% CO2 increase – preindustrial 1% CO2 increase – 20 century
Frequency of cold air over Brazil, Argentina and Uruguay • Daily data at (925hPa), 850 hPa • SLP, meridional wind and Temperature • Average over areas • 52W-57W; 23S-28S (Brazil) • 52W-57W; 28S-33S (Uruguay) • 65-60W; 33-38S (Argentina)
criterium • Temperature interval (0-2.5c , < 0c) • Reduction of temperature (5-8c; 8-10c; >10c) • Increase of SLP and southerly flow at 850hPa
ARGENTINA STATIONS OBS: TEMP. AT 2m Reanalysis: 850hPa
TEMP. 850 hPa 0-2.50 c 1960-1990 Argentina 65-60W 33-38S FUTURE
TEMP. 850 hPa < 0 c 1960-1990 Argentina 65-60W 33-38S FUTURE
TEMP. 850 hPa 0-2.50 c 1960-1990 Brazil 52W-57W 23S-28S FUTURE
Temp. 850 hPa <00 c 1960-1990 Brazil 52W-57W 23S-28S FUTURE
Next criterium • Calculate anomalies and analyze the extremes in each area. • Use SLP and meridional wind to get cases associated with frontal systems.