Status of regional climate modeling:Status of regional climate modeling:Recommendations for WRFRecommendations for WRF

W. J. Gutowski, Jr.W. J. Gutowski, Jr.Iowa State UniversityIowa State University

Ames, IowaAmes, Iowa

WRF Workshop (March 2005)

with thanks to: with thanks to: C. Anderson, R. W. Arritt, Z. Pan, E. S. TakleC. Anderson, R. W. Arritt, Z. Pan, E. S. Takle

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

Frequent MCCs

Laing & Fritsch (1997)

Mesoscale Circulation FactorsMesoscale Circulation Factors

Frequent MCCs

Laing & Fritsch (1997)

Mesoscale Circulation FactorsMesoscale Circulation Factors

High Terrain

Stensrud (1996)

Low-level Jets

Mesoscale Circulation FactorsMesoscale Circulation Factors

(Marengo, 2003)

Anderson et al. (2003)

from -from -

Project to Project to Intercompare Intercompare Regional Regional Climate Climate SimulationsSimulations

North-Central North-Central U.S. U.S.

Does higher Does higher resolution help?resolution help?

Flory (2003)

5 km

20 km

OBS

Pre

cip

itatio

n [m

m/h

r]

Yampa Basin, ColoradoYampa Basin, ColoradoAdapted from Hay et al. (2004)Adapted from Hay et al. (2004)

Gauge Analysis

20 km 5 km 1.7 km

Anderson et al. (2003)

Precipitation [mm]Precipitation [mm]PIRCS Exp.1b PIRCS Exp.1b June-July 1993June-July 1993

Observed

Model Composite

Anderson (2004)

= convective precip. = 925 mb wind

MM5 with MM5 with modified modified convective convective cloud cloud microphysicsmicrophysics

RegCM2 - 10 yr. simulations RegCM2 - 10 yr. simulations Precipitation bias vs. VEMAP

[mm/d]Gutowski et al. (2004)

Liang et al. (2004)

Generic Generic Precipitation Precipitation DeficitDeficit

WRF, too? WRF, too?

36-hr Forecast

Gauge Analysis

WRF parameterizations

Radiation

• Kain-Fritsch (KF2) • Betts-Miller-Janjic (Eta)• Grell-Devenyi ensemble

Microphysics

• Kessler • Lin et al. • WSM3 • WSM5 • EGCP01 (Eta, Ferrier) WSM6

PBL

• YSU• Mellor-Yamada-Janjic (Eta)

Convection

Longwave• RRTM • GFDL (Eta)

Shortwave• Dudhia (MM5) • Goddard • GFDL (Eta)

Recommendations for WRFRecommendations for WRF

1. Avoid implementing many parameterization options in standard model, ...

2. Promote diagnosing physics of parameterizations and their couplings.

WRF Workshop (March 2005)

WRF parameterizations …

Radiation

• Kain-Fritsch (KF2) • Betts-Miller-Janjic (Eta)• Grell-Devenyi ensemble

Microphysics• Kessler • Lin et al. • WSM3 • WSM5 • EGCP01 (Eta, Ferrier) WSM6

PBL• YSU• Mellor-Yamada-Janjic (Eta)

Convection

Longwave• RRTM • GFDL (Eta)

Shortwave• Dudhia (MM5) • Goddard • GFDL (Eta)

… should they include CCSM’s?

Recommendations for WRFRecommendations for WRF

1. Avoid implementing many parameterization options in standard model, …but include CCSM parameterizations

WRF Workshop (March 2005)

2. Promote diagnosing physics of parameterizations and their couplings.

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

von Storch et al. (2004)

Spectral Nudging

[mm]

7902 7905 7908 7911IS

U

MM

5S

IO

RS

MC

RC

MP

NN

L

MM

5

Prec

0

5

10

15

20

25

0 5 10 15 20 25

U Component (850 hPa)

OCTJANAPRJUL

MM5 RMSD [m/s]

Pan-Pan-Arctic Arctic SimulatioSimulationn

RMS RMS Difference Difference from from RawinsondRawinsondeses

Wei et al. (2002)

0

5

10

15

20

25

0 5 10 15 20 25

V Component (850 hPa)

OCTJANAPRJUL

MM5 RMSD [m/s]Wei et al. (2002)

Pan-Pan-Arctic Arctic SimulatioSimulationn

RMS RMS Difference Difference from from RawinsondRawinsondeses

Recommendations for WRFRecommendations for WRF

3. Should WRF/climate include interior nudging? No.

WRF Workshop (March 2005)

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

Central U.S. Central U.S. Warm Season Warm Season SimulationSimulation

Flory (2003)

Recommendations for WRFRecommendations for WRF

4. Promote exploration of non-hydrostatic simulations and exploit advances in cloud microphysics modeling.

WRF Workshop (March 2005)

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

Stensrud (1996)

Does regional, extratropical convection affect

climatological large-scale circulation?

(Diabatic - No Diabatic) Simulation200 hPa Heights and Winds

Stensrud (1996)Contours: 20 mContours: 20 m Barbs: 5 m/sBarbs: 5 m/s

[96 hr from 00 UTC 11 May 1982][96 hr from 00 UTC 11 May 1982]

Recommendations for WRFRecommendations for WRF

5. Analyze large-scale tendencies due to WRF convection, 5. Analyze large-scale tendencies due to WRF convection, especially in diurnal cycle.especially in diurnal cycle.

WRF Workshop (March 2005)

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

North American Regional Climate Change North American Regional Climate Change Assessment Program Assessment Program

GOALSGOALS

• Explore multiple uncertainties in regional and global climate model Explore multiple uncertainties in regional and global climate model projections at the regional scales projections at the regional scales

• DDevelop multiple high resolution regional climate scenarios for use in evelop multiple high resolution regional climate scenarios for use in impacts modelsimpacts models

• FFurther evaluate regional model performance over North America urther evaluate regional model performance over North America • EExplore some remaining uncertainties in regional climate modeling (e.g., xplore some remaining uncertainties in regional climate modeling (e.g.,

sensitivity to domain size, importance of compatibility of physics in nesting sensitivity to domain size, importance of compatibility of physics in nesting and nested models)and nested models)

• Create greater collaboration between US and Canadian climate modeling Create greater collaboration between US and Canadian climate modeling groups, as well as with the European modeling communitygroups, as well as with the European modeling community

A2 Emissions Scenario

GFDL CCSM HADAM3link to European

Prudence

CGCM3

1960-1990 current 2040-2070 futureProvide boundary conditions

MM5Iowa State/

PNNL

RegCM3UC Santa Cruz

ICTP

CRCMQuebec,Ouranos

HADRM3Hadley Centre

RSMScripps

WRFNCAR/PNNL

North American Regional Climate Change North American Regional Climate Change Assessment ProgramAssessment Program

Inter-CSE Transferabilty (ICTS):Inter-CSE Transferabilty (ICTS):An application of CEOP dataAn application of CEOP data

B. Rockel, J. Roads, I. Meinke, B. Rockel, J. Roads, I. Meinke,

W.J. Gutowski, R.W. Arrit & Gene TakleW.J. Gutowski, R.W. Arrit & Gene Takle

Continental Scale Experiments (CSEs)

MAGS BALTEX GAMEGAPP

LBA/LPB AMMA MDB

Primary ObjectivesPrimary Objectives• Study transferability of RCMs to different CSE’s Study transferability of RCMs to different CSE’s

(i.e. to different climate regimes)(i.e. to different climate regimes)

• Apply CEOP and other observational data sets to Apply CEOP and other observational data sets to evaluate simulated energy and water cyclesevaluate simulated energy and water cycles

Precipitation: Observed vs. Simulated Murray-Darling Basin (Jul-Aug-Sep)

[mm]

Recommendations for WRFRecommendations for WRF

6. Perform NARCCAP and ICTS simulations.6. Perform NARCCAP and ICTS simulations.

WRF Workshop (March 2005)

TopicsTopics

ParameterizationParameterization

Boundary conditionsBoundary conditions

ResolutionResolution

UpscalingUpscaling

TestingTesting

DiagnosticsDiagnostics

WRF Workshop (March 2005)

netcdf wrfout {dimensions:

Time = UNLIMITED ; // (1 currently)DateStrLen = 19 ;west_east = 119 ;south_north = 119 ;west_east_stag = 120 ;bottom_top = 34 ;south_north_stag = 120 ;bottom_top_stag = 35 ;ext_scalar = 1 ;soil_layers_stag = 4 ;

variables:char Times(Time, DateStrLen) ;float LU_INDEX(Time, south_north, west_east) ;

LU_INDEX:FieldType = 104 ;LU_INDEX:MemoryOrder = "XY " ;LU_INDEX:description = "LAND USE CATEGORY" ;LU_INDEX:units = "" ;LU_INDEX:stagger = "" ;

float T2(Time, south_north, west_east) ;T2:FieldType = 104 ;T2:MemoryOrder = "XY " ;T2:description = "TEMP at 2 M" ;T2:units = "K" ;T2:stagger = "" ;

float SFROFF(Time, south_north, west_east) ;SFROFF:FieldType = 104 ;SFROFF:MemoryOrder = "XY " ;SFROFF:description = "SURFACE RUNOFF" ;SFROFF:units = "mm" ;SFROFF:stagger = "" ;

WRF has extensive, flexible WRF has extensive, flexible output optionsoutput options

Possible climate extensions:Possible climate extensions:

• Daily min/max TDaily min/max T

• Water & energy budgetsWater & energy budgets

• Cloud-radiative forcingCloud-radiative forcing

Recommendations for WRFRecommendations for WRF

7. Implement a “climate suite” of diagnostics.7. Implement a “climate suite” of diagnostics.

WRF Workshop (March 2005)

Change in Daily max{T} for June-July-August(RegCM2 simulation: 2040s - 1990s)

Pan et al., (2004)

˚C

T [K] - JJA (2000-1976)

[Adapted from Folland et al. (2001) - IPCC TAR]

Recommendations for WRFRecommendations for WRF

8. Determine WRF’s added value.8. Determine WRF’s added value.

WRF Workshop (March 2005)

Recommendations for WRFRecommendations for WRF

1. Avoid implementing many parameterization options in standard model, but include CCSM parameterizations

2. Promote diagnosing physics of parameterizations and their couplings.

3. Should WRF/climate include interior nudging? No.

4. Promote exploration of non-hydrostatic simulations and exploit advances in cloud microphysics modeling.

WRF Workshop (March 2005)

Recommendations for WRFRecommendations for WRF

5. Analyze large-scale tendencies due to WRF convection, esp. in 5. Analyze large-scale tendencies due to WRF convection, esp. in diurnal cycle.diurnal cycle.

6. Perform NARCCAP and ICTS simulations.6. Perform NARCCAP and ICTS simulations.

7. Implement a “climate suite” of diagnostics.7. Implement a “climate suite” of diagnostics.

8. Determine WRF’s added value.8. Determine WRF’s added value.

WRF Workshop (March 2005)

Thank you!

WRF Workshop (March 2005)