CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE...
Transcript of CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE...
![Page 1: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/1.jpg)
CONTINENTAL SCALE SIMULATION OF CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOONTHE SOUTH AMERICAN MONSOON
(plus ACC simulations)(plus ACC simulations)
MARK FALVEY AND RENE GARREAUDMARK FALVEY AND RENE GARREAUDThanks to Ricardo Muñoz, Thanks to Ricardo Muñoz, MaisaMaisa Rojas, Rojas, HumbertoHumberto FuenzalidaFuenzalida
Department of GeophysicsDepartment of GeophysicsUNIVERSITY OF CHILEUNIVERSITY OF CHILE
VPM11 VPM11 –– March 2008March 2008
![Page 2: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/2.jpg)
CONTEXCONTEX* VAMOS modeling plan stresses the use of multi-scale
approach to capture interactions between the local scale processes and regional and larger scale variability.
* DGF has ample experience with WRF and MM5 for short term simulations. Both models allow an easy way to test parameterizations, modify topography and other BC.
LONG TERM GOALLONG TERM GOALUse the WRF model as a modeling framework for quantitatively testing
hypothesis on the impacts of different types of forcing on SAMS variability over a wide range of timescales (diurnal to inter-annual). e.g, SST, Soil moisture, Transient eddies (i.e, cold surges)
SHORT TERM GOALS…SHORT TERM GOALS…Verify that WRF gives a reasonable simulation of SAMS precipitation and
circulation patterns
Determine ‘optimal’ model settings
1. CONTINENTAL SCALE WRF SIMULATIONS1. CONTINENTAL SCALE WRF SIMULATIONS
![Page 3: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/3.jpg)
EXPERIMENTAL SETUPEXPERIMENTAL SETUPTime Period:Time Period:
July 30 2000 – April 1 2003
(Includes SALLJEX observing period)
Domain:Domain:72 km horizontal spacing
38 vertical levels
Dynamics:Dynamics:ARW core (v2.2)
Hydrostatic
Physics:Physics:KF (new) Convection
Ferrier Microphysics
NOAA LSM
MYJ Boundary Layer
Boundary Condition:Boundary Condition:6 h NCEP/NCAR Reanalysis
Monthly SODA 0.5° SST Analysis
Integrated continuously, no nudging, no re-initialization
![Page 4: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/4.jpg)
MEAN SUMMER PRECIPITATIONMEAN SUMMER PRECIPITATIONW
RF
OB
S
Liebmann and Allured, 20051° Analysis of Daily Raingauge
Dec
embe
r-Jan
uary
-Feb
ruar
y (2
001-
2003
, 3 s
umm
ers)
![Page 5: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/5.jpg)
WR
FO
BS
MEAN WINTER PRECIPITATIONMEAN WINTER PRECIPITATION
June
-Jul
y-A
ugus
t (2
001-
2002
, 2 w
inte
rs)
![Page 6: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/6.jpg)
PRECIPITATION ERRORSPRECIPITATION ERRORS
![Page 7: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/7.jpg)
ANNUAL CYCLEANNUAL CYCLE
![Page 8: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/8.jpg)
SEASONAL AND SUBSEASONAL AND SUB--SEASONAL VARIABILITYSEASONAL VARIABILITY
![Page 9: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/9.jpg)
• WRF convective precipitation precedes cloudiness observations by 6 hours
• But WRF’s precipitation maxima between 1200-1500 UTC agrees with TRMM climatologies (not shown)
DIURNAL CYCLEDIURNAL CYCLE
![Page 10: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/10.jpg)
FREQUENCY OF PRECIPITATION OCCURANCEFREQUENCY OF PRECIPITATION OCCURANCE
Monsoon (DJF) Only
![Page 11: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/11.jpg)
VALDATION : LOW LEVEL CIRCULATION (850 hPa)VALDATION : LOW LEVEL CIRCULATION (850 hPa)
![Page 12: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/12.jpg)
VALDATION : COLD SURGESVALDATION : COLD SURGES
It has been suggested that cold surges east of the Andes may have an important influence on the south-east extension of precipitation in the SAMS (e.g., Li and Fu, 2006)
Therefore it is relevant to examine whether WRF is able to reproduce cold surges:
Cold Surge Index (CSI) = -(T’ V’) (Km/s)
Where T’ and V’ are the anomalies of temperature and meridional wind with respect to their monthly means.
Positive CSI means unusually cold, northerly flow (or unusually warm southerly flow)
![Page 13: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/13.jpg)
Observing Period = December 2002 – March 2003
Radiosonde and PIBAL (Pilot Balloon) measurements at several stations that are NOT included in the Reanalysis
Region of the SALLJ is one of those where large differences between WRF and Reanalysis are found…
VALDATION : SALLJEX OBSERVATIONSVALDATION : SALLJEX OBSERVATIONS
![Page 14: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/14.jpg)
VALDATION OF ATMOSPERIC FIELDS:VALDATION OF ATMOSPERIC FIELDS:LOW LEVEL JET AND COLD SURGESLOW LEVEL JET AND COLD SURGES
![Page 15: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/15.jpg)
VALDATION OF ATMOSPERIC FIELDS:VALDATION OF ATMOSPERIC FIELDS:TEMPERATURETEMPERATURE
![Page 16: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/16.jpg)
CONVECTIVE PARAMETERIZATION: KF CONVECTIVE PARAMETERIZATION: KF vsvs BMJBMJ
![Page 17: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/17.jpg)
ALTERNATIVE SEA SURFACE TEMPERATURESALTERNATIVE SEA SURFACE TEMPERATURES
Oct Dec Feb Apr May
Unrealistic SST = disaster for the SAMS…
Reanalysis/CMAP
WRF constant winter SST
![Page 18: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/18.jpg)
SAMS SIMULATIONS SAMS SIMULATIONS -- CONCLUSIONSCONCLUSIONS
The WRF model has been run continuously over three years over the entire South American continent at low resolution.
Precipitation is generally well simulated: Major spatial patterns are captured and annual cycles, intra-seasonal variability, diurnal cycles and precipitation occurrence frequencies are well reproduced.
But there are regions where (orographic) rainfall is over greatly predicted, including NW Brazil, Northern Amazonia, the entire length of the Andes (E and W sides)
Kain-Fristch CP seems to work better than Betts-Miller-Janjic in this case
A reasonable SST is essential
Future Work = More simulations: Other physics schemes, Higher spatial resolution, longer time periods (> 10 years)
![Page 19: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/19.jpg)
PRECIS - 25 kmBL, A2, B2: 30 yr each
WRF - 15 kmRea, BL, A2: 20 yr each
PRECIS - 25 kmBL, A2: 30 yr each
DGF-UChile: ACC Simulationswww.dgf.uchile.cl/PRECIS
![Page 20: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/20.jpg)
PRECIS-DGF Rfuturo / Rpresente
Futuro: 2071-2100 / Presente: 1961-1990
![Page 21: CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN … · 2009-10-09 · CONTINENTAL SCALE SIMULATION OF THE SOUTH AMERICAN MONSOON (plus ACC simulations) MARK FALVEY AND RENE GARREAUD](https://reader034.fdocuments.in/reader034/viewer/2022042415/5f30c407ff5bc05521373c2b/html5/thumbnails/21.jpg)