Post on 31-Dec-2015
description
CPTEC’s Climate Simulations
over South America: A Preliminary Comparison A Preliminary Comparison
between the regional model between the regional model ETA and RegCMETA and RegCM
Julio Pablo Reyes Fernandez
Centro de Previsao do Tempo e Estudos Climaticos CPTEC
Divisao de Modelagem e Desenvolvimento DMD
Introduction:Introduction:
South America: tropical and South America: tropical and extratropical interaction, topographyextratropical interaction, topography
Last papers (Table 1)Last papers (Table 1)
Objective:Objective:
Compare perfomance for January of Compare perfomance for January of 1998 for the regional climate models 1998 for the regional climate models in use at CPTECin use at CPTEC
ETA: operational and research, using ETA: operational and research, using GCM CPTEC/COLAGCM CPTEC/COLA
RegCM2.9: researchRegCM2.9: research
Main Differences: parameterizations, Main Differences: parameterizations, vertical coordinate, etcvertical coordinate, etc
Models
Design of ExperimentsDesign of Experiments
Austral summer (January), from 00Z16DEC of Austral summer (January), from 00Z16DEC of 1997 to 00Z1FEB of 1998 (spin-up)1997 to 00Z1FEB of 1998 (spin-up)
Area: Tropical South America (resolution 80km)Area: Tropical South America (resolution 80km)
Initial and boundary conditions: reanalysis Initial and boundary conditions: reanalysis NCEP/NCAR, every 6 hours and SST Reynolds et NCEP/NCAR, every 6 hours and SST Reynolds et al. 1995al. 1995
Model validation: for precipitation GPCP data, and Model validation: for precipitation GPCP data, and reanalysis for others fieldsreanalysis for others fields
ValidationValidation
Areas: Amazon, NE, SE, ANDES, Areas: Amazon, NE, SE, ANDES, South and allSouth and all
Precipitation: BIAS, THREAT SCOREPrecipitation: BIAS, THREAT SCORE
Wind of lower and upper levels (850 Wind of lower and upper levels (850 and 200hPa) and geopotentialand 200hPa) and geopotential
Preliminary resultsPreliminary results
The results showed a better The results showed a better perfomance of the RegCM vs ETAperfomance of the RegCM vs ETA
Tuning of the subgrid Tuning of the subgrid parameterizations are necessary in parameterizations are necessary in both modelsboth models
Change the radiation Change the radiation parameterization of the ETA modelparameterization of the ETA model
Next FutureNext FuturePerform long integrations with both models Perform long integrations with both models
for validation with the present climate. for validation with the present climate.
1.- Use NCEP and ECMWF reanalysis1.- Use NCEP and ECMWF reanalysis
2.- Use GCM CPTEC/COLA2.- Use GCM CPTEC/COLA
The ultimate goal is their use in The ultimate goal is their use in experiments of paleoclimate and climate experiments of paleoclimate and climate changechange