ideas on wof nwp design - relationship to hrrr(e) -possible contributions from amb/gsd stan benjamin...

Ideas on WoF NWP design - Relationship to HRRR(E)

-Possible contributions from AMB/GSD

Stan BenjaminSteve Weygandt

Rapid Refresh domain

RUC-13 domain

HRRR 3-km

future 1-km nests

rapidrefresh.noaa.gov/hrrrconus

Assimilation and Modeling Branch

Global Systems Division

WoF Kickoff Meeting18 Feb 2010

WoF/HRRR/brain dump Outline -

• Current HRRR status• HRRR / RR HRRRE / NARRE superHRRRE• Radar QC

• hybcloud – satellite, bird, refl only• Data assimilation

• DFI, EnKF, hybrid• Nesting• WRF (and other) model design issues

• physics

HRRR web page – http://ruc.noaa.gov/hrrr

RUC / RR hourly updatingUse latest observations to obtain the freshest

analysis and forecasts for aviation, severe weather, energy, and general forecast applications

1-hrfcst

1-hrfcst

1-hrfcst

11 12 13Time (UTC)

AnalysisFields

3DVAR

Obs

3DVAR

Obs

Back-groun

dFields

Data types usedRawinsonde (balloons)Wind Profilers (405 MHz, 915 MHz) RASS virtual temperaturesVAD winds (WSR-88D radars)Aircraft (ACARS, TAMDAR) Surface (METAR , Buoy, MesonetPrecipitable water (GPS, GOES, SSM/I)GOES cloud-drift windsGOES cloud-top pressure/tempRadar reflectivity, lightningShip reports/dropsondesSatellite radiances (Rapid Refresh)

RUC / RR and HRRR models

Observations

Data Assimilation cycle

Hourly updating model Radar Assim

HRRR

RUC RR

NSSL verification

06z 16 Aug 2007

00z+6h HRRRRUC radar

00z+6h HRRRNo radar

RUC radar assimilation

on 13-km grid improves

HRRR 3-kmforecast

3km HRRR verification-From NCAR report

- 16 Dec 2009

“Model Performance and Sensitivity”(Mei Xu, David Dowell, Jenny Sun)

RUC grids provided much improved initial condition for HRRR than NAM or GFS grids, especially in 1-6h

RUC-based HRRR skill (even without radar assimilation)

due to effective analysis of convective environment using other observations

(ACARS, profiler, surface, cloud obs) and digital filter initialization (focuses

vertical motion for convection)

3km HRRR verification- From NCAR report

- 16 Dec 2009


Addition of radar assimilation to RUC convective environment adds further improvement for first ~6h(representative example from individual case from late July 2009)






• physics

2010-2011

1111

NAM• NEMS based NMM• Bgrid replaces Egrid• Parent remains at 12 km• Multiple Nests Run to 48hr

– ~4 km CONUS nest– ~6 km Alaska nest– ~3 km HI & PR nests, and/or a

~1.5-2km DHS/FireWeather/IMET ~1.5-2km DHS/FireWeather/IMET are possible

Rapid Refresh• WRF-based ARW• NCEP’s GSI analysis (RR-version)• Expanded 13 km Domain to include

Alaska• Experimental 3 km HRRR @ ESRL

RUC-13 CONUS domain

WRF-Rapid Refresh domain – 2010

Original CONUS domain

Experimental 3 km HRRR

Planned NCEP Operation Meso- and Storm-scale models

- Hourly cycling of land surface model fields - 6 hour spin-up cycle for hydrometeors, surface fields

Rapid Refresh Partial Cycling

RR Hourly cycling throughout the day

RR spin-upcycle

GFSmodel

GFSmodel

RR spin-upcycle

00z 03z 06z 09z 12z 15z 18z 21z 00z

Observationassimilation

Observationassimilation

Planned OperationalMeso- and Storm-scale Ensembles

2012-2013

NAM/Rapid Refresh ENSEMBLE – NRRE• Initially ~6 member ensemble made up of equal numbers of NMMB- &

ARW-based configurations• Hourly updated with forecasts to 24 hours

High Res Rapid Refresh ENSEMBLE – HRRRE• Nest HRRRE ensemble within NRRE• Opportunities to:

– Provide improved probability guidance for hazardous wx – Use for Nextgen, Warn-on-Forecast, sensible wx

Outline -

Configuration DA #memCurrent 3km HRRR RUC-DFI )13km 1

Spring 2010 “ RR-DFI +HRRR-DFI (3km) + Conv Init (GOES)

~Fall 2010 3km-HRRR+1km subnests +15min full output(hubs, RE site(s)?)

Spring 2011 RR – add chem2011? 3kmHRRR+1km-nest

+chem

Late 2011 NARRE-6 member (~13km)(RR-EnKF in testing?-OU-Xuguang/AMB

Outline -

Configuration DA #mem2012-testing 3km HRRR EnKF(?) / NARRE 1

Next HRRRE (6x CPU) 6

Add 1km HRRR (27x 3km HRRR)(grow 1km nest inside 3km HRRR as CPU becomes available, similar)

Our dream so far (but not yet WoF dream)

2015-18? 1km HRRRE-chem Hybrid EnKF/4dvar/DFI?+ 300m fixed nests (for avx, RE) ~30= “SuperHRRRE”(15-30min update frequency)

Data assimilation ideas

• Current – 3dvar, then 13kmDFI• Next – add 3km DFI• Next – incorporate DFI within 3dvar outer loop

• EnKF@13-20km, then 13km/3km DFI - may be significant improvement for mesoscale environment - initial work in FY10 under FAA (Ming Xue, Xuguang Wang w/ RR, RRgroup• Hybrid EnKF/3dvar @13km, then 13km/3km DFI• Hybrid @3km. (Does 3km DFI still add?)

HRRR Domain(s)

RUC Domain

HRRR 2010

September 2007Initial HRRR domain over the northeastern United States “aviation corridor”745 x 383 grid points, 200 processors

March 2009Domain expanded to cover approximately eastern 2/3 of the US1000 x 700 grid points, 568 processors

October 2009Domain expanded to cover CONUS1800 x 1060 grid points, 840 processors17HOURLY FREQUENCY MAINTAINED





• physics

Crude radar refl QC in RUC (and RR) -

• Start with NSSL QC• Comparison with GOES satellite (clear satellite results in radar clearing)• Water vapor moistening (reduction of subsaturation) applied• PW comparisons with GPS and RUC led to discovery of bird contamination

• Complaints from Seth Gutman – “Dr. GPS-PW”• Reflectivity vs. temperature condition developed

• 3-d Reflectivity < 28 dBz not used at night if Temp > 4°C

Crude radar refl QC in RUC (and RR) -

• Start with NSSL QC• Comparison with GOES satellite (clear satellite results in radar clearing)• Water vapor moistening (reduction of subsaturation) applied• PW comparisons with GPS and RUC led to discovery of bird contamination

• Complaints from Seth Gutman – “Dr. GPS-PW”

QC working well in general, glitch in early Aug?

Typical season variation, radar contribution to poorer fit but no regrets…





• physics

Digital Filter-based reflectivity assimilationinitializes ongoing precipitation regions

Radar reflectivity assimilation

Forward integration,full physics with radar-based latent heating

-30 min -15 min Initial +15 min + 30 min

RUC / RR HRRR model forecast

Backwards integration, no physics

Initial fields with improved balance, storm-scale circulation

+ RUC/RR Convection suppression – ask us about it…

Rapid Refresh (GSI + ARW) reflectivity assimilation example

Low-levelConvergence

Upper-levelDivergence

K=4 U-comp. diff (radar - norad)

K=17 U-comp. diff (radar - norad)

NSSL radar reflectivity (dBZ)

14z 22 Oct 2008Z = 3 km


Observations



HRRR

RUC RR


Observations



HRRR

RUC RR

2 nd pass

3-km radar

DFI analysis

18z Radar

RUC NOHRRR NO

RUC NOHRRR RAD

17 June 2009

RUC NOHRRR radar

+ 0h fcsts

HRRR with radar DA only on 3-km domain

hydrometeor

19z Radar17 June 2009

+ 1h fcsts


RUC NOHRRR NO

RUC NOHRRR RAD

RUC NOHRRR radar

hydrometeor


+ 2h fcsts


RUC NOHRRR NO

RUC NOHRRR RAD

RUC NOHRRR radar

hydrometeor

20z Radar


+ 3h fcsts


RUC NOHRRR NO

RUC NOHRRR RAD

RUC NOHRRR radar

hydrometeor





• physics

WoF/HRRR nesting ideas -

• Possibilities• WoF (HRRR dx/3) - 1-way nest in small domain• Re-initialize WoF over multi-state subset of HRRR domain at HRRR-dx

• 2-way nests to HRRR-dx/3 (and beyond)

WoF/HRRR nesting ideas -

• Possibilities• WoF (HRRR dx/3) - 1-way nest in small domain• Re-initialize WoF over multi-state subset of HRRR domain at HRRR-dx

• 2-way nests to HRRR-dx/3 (and beyond)

WoF domain du jour

WoF dx-Outer = HRRRdx-Inner = HRRR/3-……





• physics• microphysics, PBL, radiation, LSM, LES at ≤500m resolution, chemistry

NCAR-Thompson MicrophysicsRUC uses Dec 2003 version of schemeVersion in WRF v3.1 (mp_physics = 8) has many changes - 2-moment (mixing ratio and number concentration) rain helps better simulate difference in drop-size distribution between rain resulting from melting snow and that from collision-coalescence of cloud drops - Greater ice supersaturation allowed (up to water saturation) - Snow particles assumed to be more 2-d than spherical (affects

deposition, collision and fall speed) - Revised collection of snow and graupel by rain - Extensive use of lookup tables - Option for Gamma distribution for all precip hydrometeors

Subjective impressions for RR: Less graupel, more cloud ice and snow than in RUC version

34

WRF-Chem and RR

Primary WRF-Chem development and coordination occurring in GSD (Georg, Steven, Mariusz)

Next few years: introduce simple version of WRF-Chem into the RR (or even HRRR) as a first step toward integrated operational weather--air quality forecasting

- Aerosol direct effect on radiation (e.g. solar direct-beam irradiance, surface temp forecasts)

- Improved warm-rain and ice nucleation in microphysics (aerosol indirect effects) for better cloud/precip forecasts (impact on ceiling, visibility, icing, surface temp)

- First step: RR-Chem put together by Steven and Tanya

* Once per day to 48h

* Aerosol cycling only 35

(HRRR-Chem Vertically Integrated Small Aerosol Concentration (relative units) 1200 UTC 2 Sep 2009

Sources are primarily wildfires, biggest in San Gabriel Mtns, southern CA

Alternative PBL schemes available in WRF-ARW:

First-order bulk scheme. Includes a

countergradient term to parameterize nonlocal mixing.

Explicit entrainment which is proportional to surface buoyancy fluxes.

Stronger vertical mixing may alleviate the bias found in the MYJ.

2.5 and 3.0 level closure. The master length scale is a

function of 3 independent length scale (turbulent, surface layer, and stable layer).

Updated stability functions Condensation Module. Similar physics as MYJ, but

tuned to LES simulations for more aggressive vertical mixing.

MYNNYSU QNSE 2.5 level closure; similar

to MYJ in neutral-unstable conditions, but in stable conditions, QNSE scheme is activated.

Turbulent eddies and waves are treated as one entity in the stable regime.

Similar physics as MYJ, but enhanced treatment of stable nocturnal boundary layer.

PBL Scheme TestingNew candidate PBL schemes need to show skill across RR domain and reduce biases compared with MYJ. Given recent interest in the RR (and HRRR) for wind energy applications, low-level jets and coastal jet cases are good tests for the new PBL schemes.

LLJ case(s) of 20070818-19WRF-ARW Configuration (v3.1.1):13.2 and 3.3 km grid spacing51 vertical levelsRUC LSMGrell-3 Cumulus SchemeThompson Microphysics SchemeRRTM LW Radiation, Dudhia SW radiationMYJ/MYNN/QNSE/YSU PBL

Initial Conditions:GFS 6-hourly analyses

(Actual RR configuration covers all of North America)

Vertical cross-section @ 09Z 20070819

Temperature

Wind Speed

YSUMYNN

QNSEMYJ QNSE produces the strongest and widest LLJ.

YSU has the weakest and most vertically diffuse LLJ.

Of the 3 TKE-based schemes, the MYNN has stronger vertical mixing, with the jet top ~100 m higher than MYJ or QNSE.

Strength of daytime vertical mixing is similar in rank, but has more variation (not shown).

Convective probability forecasts from HRRRtime-lagged ensemble(shown with deterministic fcst)

15z + 6h HRRR and HCPF

Probability (%)

Reflectivity (dBZ)

21z 16 July ‘09Verification

3km HRRR verification- From NCAR report

- 16 Dec 2009


Addition of radar assimilation to RUC convective environment adds further improvement for first ~6h(representative example from individual case from late July 2009)


WoF/HRRRAreas of AMB contribution-

• • HRRR / RR HRRRE / NARRE superHRRRE• Radar QC

• hybcloud – satellite, bird, refl only

• Data assimilation• DFI, EnKF, hybrid (mesoscale DA in addition to stormscale)

• Nesting• WRF (and other) model design issues

• physics• microphysics, PBL, radiation, LSM, LES at ≤500m resolution, chemistry

ideas on wof nwp design - relationship to hrrr(e) -possible contributions from amb/gsd stan benjamin...

Documents

domain hrrr

h hrrr ruc radar

hrrr verification

radar ruc radar assimilation

h rucbased hrrr skill

ruc grids

ruc rr hourly

esrl ruc