south america regional climate model simulations and seasonal forecast julio pablo reyes fernandez...

South America regional climate model simulations and seasonal

forecast

Julio Pablo Reyes FernandezCenter for Weather Forecast and Climate Studies

CPTEC

1st Ibero-American Workshop on Climate Dynamics, Climate Change and Regional Climate Modeling, SP 20-23 Aug 2007

Outline

• Introduction– Short Review RCM over South America– RCM History at CPTEC

• Models • Experiments and results • Summary• Future

– Where are going


Introduction

• Necessity regional climate information (Added value)

• Regional climate models supply adequate representation of physical process and high spatial resolution

• The RegCM are based on NWP models with suitably modified radiative transfer and land surface process


Spatial Scales

Vari

an

ce

Global Model

Well resolved

Insufficiently

resolved

Added Value

Well resolved

Insufficiently resolved

Regional Model

von Storch, 2004


• Review papers: Giorgi and Mearns (1991), McGregor (1997), Giorgi and Mearns (1999), Giorgi et al. (IPCC 2001), Leung et al. (2003), Wang et al. (2004), Laprise (2006)


Short Review

• RCM studies over South America (~15 years)• Low to high spatial resolution (100-20km)• Months to years (nowdays)• Tuning to tropical region (few information)


South America is a challenge for climate modeling community

• Large spatial domain, position, particular characteristics


Fernandez, 2004


Chen, Shyh-Chin and John O. Roads Impact of Soil Moisture on Regional Spectral Model Interannual Simulations for South America. Journal of Hydrometeorology. 2003 Chen, S. and J. Roads, 2003: Regional Spectral Model Simulations for South America. J. Hydrometeor. (submitted) Chou, S.C.; Bustamante, J.F.; Gomes, J.L. Evaluation of Eta model seasonal forecasts over South America. Nonlinear Processes In Geophysics, 12 (4): 537-555, 2005 Cook KH,Vizy EK (2006) South American climate during the Last Glacial Maximum: Delayed onset of the South American monsoon. Journal of Geophysical Research 111(d2): D02110. Eltahir, EAB; Bras, RL Sensitivity of regional climate to deforestation in the Amazon basin Advances In Water Resources, 17: 101-115. 1994 Fernandez, JPR; Franchito, SH; Rao, VB Simulations of the Summer circulation over South America by two Regional Climate Models. Part I: Mean Climatology, model Theoretical And Applied Climatology, 2006 Fernandez, JPR; Franchito, SH; Rao, VB Simulations of the Summer circulation over South America by two Regional Climate Models. Part II: A comparison between 1997/1998 El Niño and 1998/1999 La Niña events, Theoretical And Applied Climatology, 2006 Gandu, AW; Cohen, JCP; de Souza, JRS Simulation of deforestation in eastern Amazonia using a high-resolution model Theoretical And Applied Climatology, 78 (1-3): 123-135 JUN 2004 Grimm, A. Jeremy Pal, and Filippo Giorgi Connection Between Spring Conditions and Peak Summer Monsoon Rainfall in South America: Role of Soil Moisture, Surface Temperature and Topography in Eastern Brazil 2007, J Climate Horel, JD; Pechmann, JB; Hahmann, AN; et al. Simulations of the Amazon Basin circulation with a Regional Model Journal Of Climate, 7 (1): 56-71 JAN 1994 Misra V (2007) Addressing the Issue of Systematic Errors in a Regional Climate Model. Journal of Climate 20(5): 801. Pal, J; Giorgi, F; Bi, X; Elguindi, N; et al. The ICTP RegCM3 and RegCNET: Regional Climate Modeling for the Developing World. Bulletin Of The American Meteorological Society, 2007 Qian, JH; Seth, A; Zebiak, S Reinitialized versus continuous simulations for regional climate downscaling Monthly Weather Review, 131 (11): 2857-2874 NOV 2003 Qian, J.-H., and F. Giorgi, 2006: Evaluation of a limited-area climate model using a variable-resolution stretched grid for seasonal simulation over South America. J. Geophys. Res., Submitted.


Rauscher, S., A. Seth, J. Qian, and S. Camargo, 2006: Regional climate model domain choice in the tropics based on process considerations, Theoretical and Applied Climatology, doi:10.1007/s00704-006-0206-z. Rauscher, Sara A., Anji Seth, Brant Liebmann, Jian-Hua Qian, and Suzana J. Camargo, 2007: Regional climate model-simulated timing and character of seasonal rains in South America. Monthly Weather Review, 135, 2642-2657. Roads, J., S. Chen, L. Druyan, M. Fulakeza, S. Cocke, T. Larrow, J.-H.Qian, and S. Zebiak, 2003: International Research Institute/Applied Research Centers (IRI/ARCs) regional model intercomparison over South America. J. Geophys. Res., 108(D14), 4425, doi:10.1029/2002JD003201 Seth, A; Rojas, M; Liebmann, B; et al. Daily rainfall analysis for South America from a regional climate model and station observations Geophysical Research Letters, 31 (7): Art. No. L07213 APR 14 2004 Seth A, Rauscher SA, Camargo SJ, Qian J,Pal JS (2007) RegCM3 regional climatologies for South America using reanalysis and ECHAM global model driving fields. Climate Dynamics 28(5): 461. Sun, LQ; Moncunill, DF; Li, HL; et al. Climate downscaling over Nordeste, Brazil, using the NCEP RSM97 Journal Of Climate, 18 (4): 551-567 FEB 15 2005 Tarasova, TA; Fernandez, JPR; Pisnitchenko, JA; Marengo, JA; Ceballos, JC; Bottino, MJ. The impact of new solar radiation parameterization in the ETA modelo in the simulation of summer climate over South América. Journal Of Applied Meteorology, 2006 Vizy, EK; Cook, KH Evaluation of Last Glacial Maximum sea surface temperature reconstructions through their influence on South American climate Journal Of Geophysical Research-Atmospheres, 110 (D11): Art. No. D11105 JUN 7 2005 Vizy EK,Cook KH (2007) Relationship between Amazon and high Andes rainfall. Journal of Geophysical Research 112(d7): D07107. Wang, YQ; Xie, SP; Xu, HM; et al. Regional model simulations of marine boundary layer clouds over the southeast Pacific off South America. Part I: Control experiment Monthly Weather Review, 132 (1): 274-296 JAN 2004 Wang, YQ; Xu, HM; Xie, SP Regional model simulations of marine boundary layer clouds over the southeast pacific off South America. part II: Sensitivity experiments. Monthly Weather Review, 132 (11): 2650-2668 NOV 2004 Xu, HM; Wang, YQ; Xie, SP Effects of the Andes on eastern Pacific climate: A regional atmospheric model study Journal Of Climate, 17 (3): 589-602 FEB 2004 Others Berthier, E. Modélisation méso-échelle du climat sud-americain. (French) Diploma Thesis Tanajura, CAS; A Vernekar, B Kirtman 2000 A Simulation of the South American summer climate with the NCEP Eta model and the COLA GCM. Tanajura, CAS; J Shukla 2000 Modeling the effects of the Andes on the South American summer climate.


Applications

• Studies– Climate change– Climate system– Development and validation– Impact– Paleoclimate– Process– Seasonal prediction


Regional models at CPTEC

• History– 1994 CPTEC– 1996 operational regional model ETA

• 40km South america – 1998 ETA extended integrations – 1-month long

• GCM-driven “Control” experiments• Dry and wet season

– 2000 ETA seasonal integrations• 4.5 months

– 2000 at present BRAMS quality air


– 2003 at present Data Assimilation • RPSAS and EKF

– 2004 at present Regional climate model development

• Perfect LBC experiments (NCEP, ECMWF)– 2005 at present experiments of climate conditions

different from present• Climate change• HadRCM, ETA, RegCM3


Objetives

To use regional climate models to assess regional consequences of global climate change is necessary firstly analyzed their present climate simulations.

In this talk show some characteristic of model performance, namely, correlation of climatological means and biases to identify systematic model errors and also others experiments at CPTEC.

Development and validation, process, climate change and seasonal prediction


Models

• CPTEC´s ETA

• ICTP RegCM3

• BRAMS


ETA model modifications

ETA NCEP regional model (Mesinger et al. 1988). To perform climate integration the original code was strongly modified. There were made multiple changes and corrections:

(a) developed an interface which allows the ETA model to start from different data and to use them for the time dependent boundary conditions;

(b) modified the SST update program to use climatological and operational SST data;


(a) modified the insolation programs to use the 360 days year HadAM3H data; new solar and long wave radiation scheme;

(b) restart code;

(c) corrected all shortcomings that don’t permit to run the model for the period more than 3 years

The integrations were performed on the supercomputer SX6


Domain1st Ibero-American Workshop on Climate Dynamics, Climate Change and Regional Climate Modeling, SP 20-23 Aug 2007

Experiments and results


Simulations of the Summer Circulations

• Design– RegCM3 and ETACLIM– 10-years integration for Austral summer (January)– 80 km resolution

• Capabilities


Fernandez et al., 2006a TAC

Table 1 Characteristics and configurations of the models.

Features ETACLIM RegCM3

Physics

Cumulus BMJ Grell

Radiation GFDL CCM3

PBL Mellor-Yamada Holstag

LSM NOAH BATS

Vertical resolution 38 eta levels 14 sigma levels

Horizontal resolution 47x67 71x54

Dynamics Hydrostatic Hydrostatic


Transferability and subgrid

• Design– 50 kms over different regions– Reanalysis NCEP/DOE II

• Temperature and Precipitation skill over different domains

• Sub-BATS at medium resolution – (50 km 10km)

• INPE, USP, IGP, INM


Fernandez, Rocha, Martinez and Silva, 2006


Peruvian Andes Caribbean Eaat Europe Dry Wet Dry Wet Dry Wet

January 1992

January 1994

June 2004

June 1995

July 2000

July 1999

Fernandez, Rocha, Silva, Martinez, Cirisan 2006


Impact the new solar radiation scheme

• Design– 2003 Austral Summer (January)– 40km resolution– Reanalysis NCEP/DOE II– Reynolds and Smith´s SST

• Impact on surface fluxes, temperature and precipitation

Tarasova, Fernandez, Pisnichenko, Marengo, Caballos and Bottino, 2006 JAMC


The INPE ETA model for Climate Change Simulations (CCS)

• Design– 40km resolution– Long-term 5-year continuous integration– 1979-1984 Reanalysis NCEP/DOE II

• Validation and adjust

Fernandez, Pisnichenko, Tarasova, 2007


Forcing and simulations

Salathé, Steed, Mass, and Zahn, 2007 JC

Pisnichenko, I.A., T.A.Tarasova, J.P.R. Fernandez, Pisnichenko, I.A., T.A.Tarasova, J.P.R. Fernandez, and J. Marengo, 2006, 8and J. Marengo, 2006, 8thth CSHMO CSHMO


Fig 4 Simulated rainfall monthly means.


Fig 5 Simulated air temperature monthly means.


Comparison


Rauscher et al. 2007, MWR


ETACLIM, 1979-1983 NNRP2


Fig 7 Diurnal cycle (UTC) of rainfall (3 hour period).


DEEP SOIL TEMPERATURE

Impact in our climate simulations


Climate change experiments

• Design– 40km resolution– Long-term 2 x 30-year continous integrations– 1960-1990 and 2070-2100– HadAM3H data

Pisnichenko, Tarasova and Fernandez, 2006Marengo et al. 2007


Seasonal simulations hindcasts mode

• Design– 40 km resolution– Ensemble mixed physics– 1979-2002 General Circulation Atmospheric

Model CPTEC and reanalysis

• Improvement seasonal forecastChou et al. 2005In progress


Summary

• In order to perform long simulations (climate) several refinements are made to the ETA configuration used for weather forecasting over the South America as the climate model

• The annual cycle of precipitation and temperature is well captured

• The simulations shows a tendency to underestimate precipitation, mainly in the austral summer and transition seasons (DJF) with exception in winter (JJA)


Summary - cont

• The regional seasonal temperature show a positive biases

• Also the values of ρ between the simulated and observated data are in general high in almost all the regions (Table 1)

• Analysis of diurnal cycle of precipitation and soil temperatures shows some shortcommings

• The ETA model provides similar skill than others regional models


Summary - cont

• A new solar radiation scheme has been implemented into the Eta Model

• Nevertheless, a systematic difference remains (10%–20%), probably because of the incorrect description of cloud parameters

• The original version of the model reproduces a monthly mean precipitation rate closer to the GPCP observational data as compared with the modified


Summary - cont

• The transferability experiments show that both models successful simulate the climate variability over different regions

• The coupling of the physics parameterizations seems to work better in RegCM3 than in ETACLIM for Middle latitude and Caribbean than for the Peruvian Andes and Europe

• The sub-BATS experiments show small increment of skill over Europe and Caribbean regions, but no over the Andes


Summary - cont• Futher analysis of the difference between

simulations and observations will aid in the identification the causes and help to tune the RCMs

• Further changes in physical parameterizations of the model aimed to obtain better model performance

• Identify what regions has better model skill and higher climate predictability will be reduce the incertain when used in climate change simulations


Future

• Where are going

– High resolutions

– Longer simulations and ensembles

– Development of Earth regional climate system models

• ocean, hydrology, biosphere, chemistry/aerosol


Thank you

Muito Obrigado

Gracias


examples

Cook, KH; Vizy, EK South American Climate during the Last Glacial Maximum: Delayed Onset of the South American Monsoon. 2005

Grimm,A.; J. Pal, F. Giorgi: Local forcing and Intraseasonal modulation of the South American Summer Monsoon: soil moisture, sea surface temperature, and topography. 2007

Pal, J; Giorgi, F; Bi, X; Elguindi, N; et al. The ICTP RegCM3 and RegCNET: Regional Climate Modeling for the Developing World. 2007

Pal et al., 2007 (BAMS)

RegCM3, 50 km, Emmanuel, DJFM 87-00, ERA 40

Topografia

Cobertura vegetal

• Pal et al. 2007, BAMS

• JFM CRU/CMAP • JFM RegCM3

Cook&Vizy,2005

Paleoclima

LGMPD

TOPO & ASST

Cook & Vizy, 2005

LGM-PD (precipitação media anual

V q

Soil moisture * 0.5 in East Brazil (Exp. 7)

Control run (2) Precipitation Wind&Temp. 850 hap

Grimm et al.,2007

Sensitividade

EBU/POM

south america regional climate model simulations and seasonal forecast julio pablo reyes fernandez...

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