An Overview of the Current and Future NCEP Operational Modeling Suite. William. M. Lapenta Acting Director Environmental Modeling Center

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N C E P An Overview of the Current and Future NCEP Operational Modeling Suite William. M. Lapenta Acting Director Environmental Modeling Center NOAA/NWS/NCEP Geoff DiMego, John Derber, Yuejian Zhu, Hendrik Tolman, Vijay Tallapragada, Shrinivas Moorthi, Mike Ek, Mark Iredell, Suru Saha NWP/WAF 29 May 2012 1 Presentation Outline NOAA Center for Weather and Climate Prediction Status Operational Computing at NOAA Major Upgrades to the Production Suite Global Forecast & Data Assimilation System (GDAS/GFS) Global Ensemble & North American Ensemble Forecast System (GEFS & NAEFS) Seasonal System (CFSv2 and NMME) CONUS Mesoscale & ensemble systems (NAM & SREF) Regional Hurricane (HWRF) Thoughts Going Forward NWP/WAF 29 May 2012 2 1

NOAA Center for Weather and Climate Prediction (NCWCP) Status A.K.A. the new building. Four-story, 268,762 square foot building in Riverdale, MD will house 800+ Federal employees, and contractors 5 NCEP Centers (NCO, EMC, HPC, OPC, CPC) NESDIS Center for Satellite Applications and Research (STAR) NESDIS Satellite Analysis Branch (SAB) OAR Air Resources Laboratory Includes 40 spaces for visiting scientists Includes 465 seat auditorium & conference center, library, deli, fitness center and health unit NWP/WAF 29 May 2012 3 Seamless Suite of Numerical Guidance Systems Spanning Weather and Climate Outlook NCEP Model Perspective Seasons Years Forecast Uncertainty Guidance Threats Assessments Forecasts Watches Warnings & Alert Coordination Forecast Lead Time Hours Minutes Days 1 Week 2 Week Months Climate Forecast System North American Ensemble Forecast System Global Ensemble Forecast System Global Forecast System Short-Range Ensemble Forecast Waves North American Mesoscale Real Time Ocean Forecast System Rapid Update Cycle for Aviation Hurricane WRF & GFDL Space Weather Dispersion Models for DHS Tsunami Benefits NWP/WAF 29 May 2012 4 2

Production Suite on Supercomputer May 2012 Nu mber of Nodes 00 06 12 18 Time of the day (utc) 75% Production 00 % Development NWP/WAF 29 May 2012 5 Comparison of IBM P6 and idataplex Systems (per site) System Lifecycle Operating Average Average Number of Date System Capability Capacity compute / batch cores Sustained TeraFLOP IBM P6 Oct 2012 Sep 2013 AIX 5.3 1.0X 1.0X 5,314 73.9 TF idataplex Dec 2012 Planned Acceptance Linux (RHEL) 1.5X over P6 1.65X over P6 7,168 149 TF Pland and Schedule: Access to a 2-node system compiling codes Full system available in September 2012 Acceptance of both systems Jan 2013 Operational no later than 1 October 2013 NWP/WAF 29 May 2012 6 3

Hybrid system Global Data Assimilation System Upgrade Most of the impact comes from this change Uses ensemble forecasts to help define background error NPP (ATMS) assimilated Quick use of data after launch Use of GPSRO Bending Angle rather than refractivity Allows use of more data (especially higher in atmos.) Small positive impacts Implemented 22 May 2012 Satellite radiance monitoring code Allows quicker awareness of problems (run every cycle) Monitoring software can automatically detect many problems Post changes Additional fields requested by forecasters (80m variables) Partnership between research and operations GFS Paper: Hybrid Paper: 1B1.2 11:30 Today: Glenn White et al. (Fanglin Yang presenting) 1E1.1 16:30 Today: Daryl Kleist and Kayo Ide NWP/WAF 29 May 2012 7 500 hpa Anomaly Correlation for Hybrid GDAS Parallel 8 Jan to 15 May 2012 (00Z cycles only) Northern Hemisphere Southern Hemisphere Operational Hybrid Para Operational Hybrid Para Day 5 Day 10 Day 5 Day 10 NWP/WAF 29 May 2012 8 4

CONUS Day-3 Precipitation Scores For Hybrid GDAS Parallel 8 Jan to 15 May 2012 (00Z cycles only) Equitable Threat Score Operational Hybrid Para Operational Hybrid Para Bias NWP/WAF 29 May 2012 9 2010-2011 Atlantic TC Track Errors For Hybrid GDAS Parallel Orange: Operational GFS Green: FY12 GFS with Hybrid GSI Day-1 Day-2 Day-3 Day-4 Day-5 ~16% Reduction at Days 4 & 5 NWP/WAF 29 May 2012 5

Global Ensemble Systems Parameter NCEP CMC NAEFS Model GFS GEM NCEP+CMC Initial uncertainty ETR EnKF ETR + EnKF Model Yes (Stochastic Pert) Yes (multi-physics) Yes uncertainty/stochastic Tropical storm Relocation None Daily frequency 00,06,12 and 18UTC 00 and 12UTC 00 and 12UTC Resolution T254L42 (d0-d8)~55km T190L42 (d8-16)~70km (d0-d16) ~ 66km 1*1 degree Control Yes Yes Yes (2) Ensemble members 20 for each cycle 20 for each cycle 40 for each cycle Forecast length 16 days (384 hours) 16 days (384 hours) 16 days Post-process Bias correction Bias correction Yes (same bias for all for each member members) Last Upgrade February 14 th 2012 August 17th 2011 GEFS Paper: 4B3.4 Thursday at 11:15: Yuejian Zhu et al. (Fanglin Yang presenting) NWP/WAF 29 May 2012 11 GEFS Upgrade Implemented 14 Feb 2012 NH 500mb Height AC 01 Sept 2011 to 30 Nov 2011 GFS Day-8 GEFS Day-9 NAEFS Day-9.25 NWP/WAF 29 May 2012 12 6

GEFS Upgrade: 2011 Atlantic Basin TC Track Errors NWP/WAF 29 May 2012 13 Advancement of Climate Forecast System (CFS) Implemented 30 March 2011 Attribute CFSv1 (Operational 2004) CFSv2 (March 2011) Analysis Resolution 200 km 27 km Atmosphere model 200 km/28 levels 100 km/64 levels Humidity based clouds Variable CO2 AER SW & LW radiation Prognostic clouds & liquid water Retuned mountain blocking Convective gravity wave drag Ocean model MOM-3: 60N-65S MOM-4 fully global 1/3 x 1 deg. ¼ x ½ deg. Assim depth 750 m Assim depth 4737 m Land surface model 2-level LSM 4 level Noah model (LSM) and assimilation No separate land data assim GLDAS driven by obs precip Sea ice Climatology Daily analysis and Prognostic sea ice Coupling Daily 30 minutes Data assimilation Retrieved soundings, 1995 analysis, uncoupled background Radiances assimilated, 2008 GSI, coupled background Reforecasts 15/month seasonal output 25/month (seasonal) 124/month (week 3-6) NWP/WAF 29 May 2012 14 7

Improved WH MJO Signal in CFSv2 50% CFSv1 CFSv2 50% 8-day lead 18-day lead NWP/WAF 29 May 2012 15 National Multi-Model Ensemble (NMME) Project Facilitated by the NOAA Climate Test Bed NMME as a Modeling Test-Bed Seasonal to Interannual Time Scales Predictability Research: e.g., South East US Drought Model Evaluation and Development Initialization Strategies: e.g., Land, Ocean Fosters interaction between research and operations Provides experimental guidance products to Climate Prediction Center Participating Organizations: University of Miami - RSMAS NASA GMAO National Center for Atmospheric Research (NCAR) NOAA/NCEP/EMC/CPC Center for Ocean-- Land-- Atmosphere Studies (COLA) NOAA/GFDL International Research Ins7tute for Climate and Society (IRI) Princeton University Canadian Meteorological Centre (Soon) University of Colorado (CIRES Data are available at: http://iridl.ldeo.columbia.edu/sources/.models/.nmme/ NWP/WAF 29 May 2012 16 8

Operational Mesoscale Modeling for CONUS: North America Model (NAM) Implemented 18 October 2011 NEMS based NMM Outer grid at 12 km to 84hr Multiple Nests Run to ~48hr 4 km CONUS nest 6 km Alaska nest 3 km HI & PR nests 1.3km DHS/FireWeather/IMET Rapid Refresh (RAP) Implemented 1 May 2012 WRF-based ARW Use of GSI analysis Expanded 13 km Domain to include Alaska Experimental 3 km HRRR WRF-Rapid Refresh domain 2010 RUC-13 CONUS domain Original CONUS domain Experimental 3 km HRRR NWP/WAF 29 May 2012 17 Preliminary Testing for NAM FY13 Upgrade Package Upper air verification against raobs (25 April to 02 May 2012) Height RMS error Operational Vector Wind RMS error Pressure (mb) Day 1 = Black Day 2 = Red Day 3 = Blue Improved physics Improved physics And EnKF in DA Pressure (mb) Day 1 = Black Day 2 = Red Day 3 = Blue Height RMS (m) Physics Modifications: GWD updated BMJ_DEV, fres=0.85 RRTM, latest version as of 3/24 Remove 4x diffusion of q, cloud water Microphysics changes Operational Physics changes Physics changes & global EnKF Vector Wind RMS (m/s) Data Assimilation Modifications: Raob level enhancement in GSI Use ensemble forecasts from the global EnKF system to compute background error covariances WARNING, WARNING, WARNING: SMALL SAMPLE SIZE NWP/WAF 29 May 2012 18 9

FY2012 SREF implementation Target Implementation July 2012 Model Changes Resolution increase from 32km/35km to 16km Eliminate Eta and RSM legacy models Upgrade WRF cores from v2.2 to version 3.3 35 levels in the vertical and 50 mb model top Initial condition and physics diversity improvement Control ICs (NDAS, GDAS, RAP blended @ edges w/gfs) IC perturbation is a blend of regional breeding and downscaled ETR Land IC (NDAS, GFS, and RAP). Physics (NAM, GFS, HWRF, NCAR and RAP) New capabilities of post-processing & product generation Precipitation bias correction Clustering and associated mean/prob/spread within a cluster Member performance ranking Downscaling to 5km using RTMA and associated ensemble products New ensemble products Max/min, mode, 10-25-50-75-90% forecasts Probs of severe thunderstorm, lightning, dry lightning, fire weather (SPC) as well as fog, LLWS, composite reflectivity and echo top Addition of hourly ensemble product output from 1-39 hr NWP/WAF 29 May 2012 19 Plans for a National Mesoscale Ensemble System Convergence of NAM, RAP, HRRR and SREF between 2016 and 2018 System must meet requirements e e of today and future Provide NextGen Enroute AND terminal guidance Provide PROBABILITY guidance with full Probability Density Function specified Address Warn-on-Forecast as resolutions evolve towards ~1 km Core elements Common data assimilation system Code Infrastructure and management system Potential Attributes of the North American Rapid Refresh Ensemble (NARRE) Hourly updated with forecasts to 24 hours Control data assimilation cycles with 3 hour preforecast period 84 hr forecasts are extensions of the 00z, 06z, 12z, & 18z runs NWP/WAF 29 May 2012 20 10

Regional Hurricane Modeling Upgrade for 2012 season (HWRF) A high-resolution hurricane model operating at cloud-permitting 3km resolution was implemented on 24 May 2012 Reflects multi-agency efforts supported by the Hurricane Forecast Improvement Project (HFIP) Three atmospheric telescoping nested domains: 27km outer domain 75x75 degree 9km intermediate nest ~11x10 degree 3km inner-most nest ~6x5 degree New centroid based nest motion algorithm, 1-D coupling in East-Pac, improved physics & vortex initialization Upgraded tracker and new high-temporal resolution (every time step) track and intensity product and new SSMI/S synthetic microwave imagery NWP/WAF 29 May 2012 21 Improved Vertical Structure (Irene09L.2011082212 15h forecast) Wind structure Smaller Size of vortex PBL height Lower PBL height NWP/WAF 29 May 2012 22 11

2010 and 2011 3km HWRF Pre-Implementation Test Results Atlantic Basin 87% of total retrospective runs from 2010-2011 seasons show 10-25% reduction in track errors and 5-15% reduction in intensity errors 37 Storms 2010: Alex, Two, Bonnie, Colin, Five, Danielle, Earl, Fiona, Gaston, Hermine, Igor, Karl, Matthew, Nicole, Otto, Paul Richard, Shary, Tomas 2011: Arlene, Bret, Cindy, Don, Emily, Franklin, Gert, Harvey, Irene, Ten, Lee, Katia, Maria, Nate, Philippe, Rina, Sean NWP/WAF 29 May 2012 23 Real Time Ocean Forecast System Implemented 24 October 2011 RTOFS Global is the first global eddy-resolving ocean forecast system at NOAA/NCEP 1/12 degree HYCOM (HYbrid Coordinate Ocean Model) 6-day forecasts initialized at 00 UTC 32 vertical hybrid layers (isopycnal in the deep, isolevel in the mixed layer and sigma in shallow waters) Initialization: MVOI scheme (NCODA) developed by the US Navy Forced with the GFS surface fluxes of radiation, precipitation and momentum. Thanks to the NAVY for partnering with NOAA and making HYCOM available NWP/WAF 29 May 2012 24 12

NEMS GFS/GOCART Aerosol Scheduled Implementation Q4FY12 Experimental (non-operational) Executable compiled from NEMS trunk code repository 120-hr dust-only forecast Once per day (00Z) 3-hourly products: 3d distribution of dust aerosols (5 bins from 0.1 10 µm) Automatic output archive, post processing and web update since June 11, 2011 Same physics and dynamics as operational GFS with the following exceptions: Column AOD @ 550nm Lower resolution (T126 L64) Use RAS with convective transport and tracer scavenging Aerosol-radiation feedback is turned off http://www.emc.ncep.noaa.gov/gmb/sarah/ngac/html/realtime.fcst.html NWP/WAF 29 May 2012 25 Linkage of Model Systems Within Production Suite ~3.5B Obs / Day Mostly Satellite +Radar Global Data Assimilation Regional Data Assimilation CLIMATE CFS GFS + MOM3/4 Global Forecast System North American Ensemble Forecast System GEFS + Canadian Global + Hurricane GFDL HWRF (NMM) North American Mesoscale NMM Short-Range Ensemble Forecast NMM + ARW + ETA + RSM Very Short Range Ensemble Forecasts Time-Lagged RR+NAM Oceans HYCOM Rapid Refresh for Aviation ARW + GSI WaveWatch III Dispersion, Ash, Smoke & Dust ARL s HYSPLIT Severe Weather NMM + ARW Air Quality NAM + EPA/ ARL s CMAQ NWP/WAF 29 May 2012 26 13

Is a Unified Modeling Approach Possible at NOAA? Global, CONUS & Hurricane 84-hour forecasts from 12Z 17 Sep 2010 Lowest model layer winds (m/s). Global NMM-B in the outermost domain NAM/NMM-B inside the global domain CONUS nest inside the NAM Moving nests of Hurricanes Igor and Julia Configuration within a single executable NWP/WAF 29 May 2012 27 Thanks for your attention and enjoy the meeting NWP/WAF 29 May 2012 28 14

Other papers/posters of interest 1B1.2 ID:5445 Tuesday 11:30: Recent and future changes in the NCEP Global Forecast System Glenn White et al. (Fanglin Yang presenting) 1E3.6 ID:5637 Tuesday 17:45: Cloud ceiling analysis in the RTMA. Yanqiu Zhu and Geoff Dimego 3D3.2 ID:5722 Thursday 15:30 Joint OSSE data set, Michiko Masutani et al. 4B3.4 ID:5418 Friday 11:15: Experiment of Multi-physics Global Ensemble System. Yuejian Zhu et al. 3B1.1 ID:5487 Thursday at 10:30 The third upgrade of NOAA's National Centers for Environmental Prediction's Real-Time Mesoscale Analysis Manuel S.f.v. De Pondeca et al. 3E1.5 ID:5466 Thursday 17:30 A comparison of ensemble perturbations generated by breeding and ensemble Kalman Filter schemes Xiaqiong Zhou et al. 2B1.5 ID:5330 Wednesday 11:45 Review of NCEP GFS Forecast Skills in 2011 and Beyond; Fanglin Yang 3B3.2 ID:5712 Thursday at 11:00 The High Resolution Rapid Refresh (HRRR): An hourly updating convection permitting forecast system nested in an hourly cycled mesoscale model with multi-scale data assimilation; Curtis Alexander et al. 1E1.1 ID:5520 Tuesday at 16:30: An OSSE-based evaluation of 4D-Ensemble-Var (and hybrid variants) for the NCEP GFS; Daryl Kleist and Kayo Ide NWP/WAF 29 May 2012 29 Dual-Resolution Coupled Hybrid 3D-VAR/EnKF member 1 forecast T254L64 member 2 forecast T254L64 member 3 forecast T574L64 forecast Uses background error covariances computed from the ensemble first-guess ensemble used to estimate background error covariances EnKF member update GSI Hybrid Ens/Var Generating new ensemble perturbations given the latest set of observations and a first-guess ensemble EnKF ensemble perturbations ti are "re-centered" around the highres analysis Replaces the EnKF ensemble mean analysis analysis Deterministic forecast member 1 analysis member 2 analysis member 3 analysis Used for GFS forecasts for next cycle Previous Cycle Current Update Cycle NWP/WAF 29 May 2012 15