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Overview of The Environmental Modeling Center Stephen J. Lord Director NCEP Environmental Modeling Center. Overview. EMC Organization Scientific highlights Weather Research & Forecast (WRF) System Hurricane Forecasting Real-time Ocean Forecasting Global Coupled Climate Forecast System
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Overview ofThe Environmental Modeling CenterStephen J. LordDirectorNCEP Environmental Modeling Center
Overview • EMC Organization • Scientific highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • The NASA-NOAA-DOD Joint Center for Satellite Data Assimilation • Summary
EMC Mission • In response to operational requirements: • Maintain • The scientific correctness and integrity of operational forecast modeling systems • Modify current operational system to adapt to ever-present external changes • Enhance numerical forecasts • Test and improve NCEP’s forecast model systems via • Scientific upgrades • Tuning • Additional observations • Transition and Develop operational numerical forecast models from research to operations • Transform & integrate • Code • Algorithms • Techniques • Manages and executes transition process including • Government technical and system performance review before implementation EMC
NCEP Mission Requirements & Forecast Suite Elements SEASONAL/INTERANNUAL CLIMATE REGIONAL ENSEMBLES GLOBAL ENSEMBLES REAL-TIME OCEAN REGIONAL NWP FIRE WEATHER RAPID UPDATE GLOBAL NWP HURRICANES AIR QUALITY National Centers for Environmental Prediction X X X X X X X X X X NCEP X X X X X X X United Kingdom Meteorological Office UKMO European Centre for Medium Range Weather Forecasting X X X ECMWF NCEP only NCEP and UKMO NCEP, UKMO and ECMWF
The Environmental Forecast Process Observations Data Assimilation Analysis Model Forecast Numerical Forecast System Post-processed Model Data Forecaster User (public, industry…)
Scientific Highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • Data Assimilation and Global Modeling (JCSDA, etc)
WRF at NCEP • 21 September 2004: 8 km WRF ARW & NMM into HiRes Window runs • April 2004 to present: explicit 4.5 km NMM runs for SPC/NSSL Spring Programs • 28 June 2005: 5-6 km HiResWindow explicit runs • November 2005: Added 6-member WRF ensemble to SREF (6 = 3 ARW +3 NMM) • June 2006: WRF-NMM and WRF-GSI replaced Eta Model and its 3D-Var in North American Mesoscale (NAM) runs • December 2006: Major upgrade
Spring Program 2007 NMM4 ARW4 Circles denote locations of rotating updrafts where updraft helicity is at least 50 m2s-2 Observed Composite Reflectivity Courtesy Kain, Weiss & Bright
Scientific Highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • Data Assimilation and Global Modeling (JCSDA, etc)
NCEP’s Hurricane Forecast Guidance • GFS • T382/64L • 3-D var • Vortex relocation • State of the science physics • GFDL • Movable nested • Air-sea coupled • Inner nest • 9 km/42L • Specialized vortex initialization, • Upgraded with some GFS physics (2003, 2004) • HWRF added to GFDL in 2007
120 hr 96 hr 72 hr 48 hr 24 hr Aug. 16, 18z
Strategic Approach: Hurricane-Wave-Ocean-Surge-Inundation Coupled Models NCEP/Environmental Modeling Center Atmosphere- Ocean-Wave-Land NOS land and coastal waters HWRF SYSTEM NMM hurricane atmosphere NOAH LSM runoff High resolution Coastal, Bay & Estuarine hydrodynamic model surge inundation fluxes Atmosphere/oceanic Boundary Layer radiative fluxes winds air temp. other fluxes elevations currents 3D salinities temperatures SST currents HYCOM 3D ocean circulation model wave spectra WAVEWATCH III Spectral wave model wave fluxes HWRF/multi-model hi-res ensembles for adv. storm surge model
Scientific Highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • Data Assimilation and Global Modeling (JCSDA, etc)
Real Time Ocean Forecasting • Wave Modeling • Global and Regional • Unified model approach • NOAA Wavewatch III • Basin-scale Ocean Model (new system) • Sea Surface Temperature & Winds • NCEP Ocean Prediction Center support • Gulfstream analysis & forecast • Real-time Sea Ice products • Alaska Region support (fishing)
Multi-Grid Wave Modeling Higher coastal model resolution Deep ocean model resolution dictated by GFS model Highest model resolution in areas of special interest Multi-grid wave model tentative resolutions in minutes for the parallel implementation in FY2007-Q4. Hurricane nests moving with storm(s) like GFDL and HWRF
NCEP Real-Time Ocean Forecast System (RTOFS)Operational December 2005, upgraded June 2007 • RTOFS provides • Routine estimation of the ocean state [T, S, U, V, W, SSH] • Daily 1 week forecast • 5 km coastal resolution • Initial and boundary conditions for local model applications • Applications • Downscaling support for water levels (with NOS) for shipping • Water quality • Ecosystem and biogeochemical prediction • Improved hurricane forecasts • Improved estimation of the atmosphere state for global and regional forecasts Chesapeake Bay
S1: Nowcast for 20070405 S2 Test: Nowcast for 20070405 Freshwater nearshore Quality, Class 1: Surface Salinity map for S1 (left panel) and S2 Test (right panel) compared to surface salinity map near mouth of Mississippi based on conductivity sensors and current meters data (middle panel) collected from moorings near the LATEX coast in 1982 (Estuaries, Wiseman & Kelly, 1994). The offshore salinity front is non-existent in S1. In S2 test, it is weaker than the one observed and is located closer to the coast.
Scientific Highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • Data Assimilation and Global Modeling (JCSDA, etc)
Ocean Model MOMv3 quasi-global 1ox1o (1/3o in tropics) 40 levels Atmospheric Model GFS (2003) T62 64 levels Seasonal to Interannual Prediction at NCEP Climate Forecast System (CFS) Reanalysis-2 3DVAR T62L28 update of the NCEP-NCAR R1 GODAS 3DVAR XBT TAO etc Argo Salinity (syn.) (TOPEX/Jason-1) D. Behringer
In the west, assimilating Argo salinity corrects the bias at the surface and the depth of the undercurrent core and captures the complex structure at 165oE. In the east, assimilating Argo salinity reduces the bias at the surface and sharpens the profile below the thermocline at 110oW. Assimilating Argo Salinity Comparison with independent ADCP currents. ADCP GODAS GODAS-A/S
Impact of Increasing Ensemble SizeOctober IC Lead 1 (DJF) Surface Temperature 5 members 10 members 15 members Precipitation
Scientific Highlights • Weather Research & Forecast (WRF) System • Hurricane Forecasting • Real-time Ocean Forecasting • Global Coupled Climate Forecast System • Data Assimilation and Global Modeling (JCSDA, etc)
Satellite Data Ingest Five Order of Magnitude Increases in SatelliteData Over Fifteen Years (2000-2015) Daily Satellite & Radar Observation Count Daily Percentage of Data Ingested into Models Level 2 Radar 2008 Data 1.0 B obs 1.0 B 100% 210 M obs Received Data 125 M obs Selected Data Assimilated Data 100 M obs Count (Millions) 17.3M 7% 6.6M 2% 1990 2000 2008 2015 Received = All observations received operationally from providers Selected = Observations selected as suitable for use Assimilated = Observations actually used by models
NASA-NOAA-DOD Joint Center for Satellite Data Assimilation (JCSDA) • NOAA, NASA, DOD partnership • Mission • Accelerate and improve the quantitative use of research and operational satellite data in weather and climate prediction models • Current generation data • Prepare for next-generation (NPOESS, METOP, research) instruments • Supports applied research • Partners • University, Government and Commercial Labs
JCSDA Instrument and Radiative Transfer Development Projects 2008-09 • New observations (implemented 1 May) • COSMIC • AIRS (all FOV) • New observations (testing) • Implemented 29 May 2007 • METOP AMSU, HSB, HIRS • GOES 1x1 FOV sounder radiances • Implemented Fall 2007 • JMA high density winds • SBUV-8 • Implemented Summer 2008 • Windsat • Observations under development • IASI – to be implemented January 2009 • OMI, GOME • ASCAT • AMSR-E • SSM/IS • CHAMP • New analysis variables • Constituent gas assimilation • Aerosols • Improved radiative transfer • Surface emissivity models • Cloud absorption & reflection • Data sets (albedo, vegetation, land type) • Unified land surface treatment (data assimilation, model) METOP advanced instruments
EMC-GMAO-STAR Code Managementfor Atmospheric Data Assimilation Process: similar to ECMWF & Météo-France who have annual code mergers But,to promote collaboration, EMC and GMAO use same repository and mergers are more frequent (3 months) GSI & CRTM supported 3 months * * * * * * * * EMC 3 1 Accepted changes * *EMC, GMAO System change Repository change +Repository Merger (new tag) 2 + + Repository Protocols 1 – EMC, GMAO take (agreed-upon) merged code from repository to begin work 2 – EMC, GMAO incorporate developments into repository 3 – Code mergers, repository changes and timing are NCEP’s decision GMAO * * * * * * * Time
Summary • Increasingly interdisciplinary and integrated forecast systems to support weather, water and S/I climate (e. g. WRF) • Increased emphasis on • Advanced data assimilation • Ocean forecasting • S/I climate • Severe weather • Ensemble systems • Transition of community research to operations at NCEP is accelerating • Advanced satellite data assimilation through the JCSDA
GFS implementation – 1 May 2007 • GSI • Unify the NCEP 3DVAR assimilation system • Some performance metrics improved (but most neutral) • Prepare for future analysis improvements (e.g. S4DVAR) • Add new observing systems • Change vertical coordinate to hybrid sigma-pressure, reducing some upper air model errors • Modernize the radiation package • Increase output particularly for hydrology
Dynamics changes • Hybrid sigma-pressure vertical coordinate • Model surface remain terrain-following in the lower troposphere but become pure pressure surfaces in the stratosphere • Reduces vertical advection errors and pressure-gradient calculation errors in the upper part of the model • Data assimilation and physics done on hybrid sigma-pressure coordinate as well
Final testing set • Retrospective testing • 15 June 2005 to 5 November 2005http://wwwt.emc.ncep.noaa.gov/gmb/para/paralog.2005tropics_retro_gsihybrid.html • 31 July 2006 to 5 November 2006 http://wwwt.emc.ncep.noaa.gov/gmb/para/paralog.2006tropics_retro_gsihybrid.html • 24 October 2006 to 5 February 2007 http://wwwt.emc.ncep.noaa.gov/gmb/para/paralog.200607winter_retro_gsihybrid.html • Real-time parallel • NCO started January 2007; in fairly final form about March 1, 2007 to presenthttp://wwwt.emc.ncep.noaa.gov/gmb/para/paralog.gsihybrid.html
2005-2006 Atlantic Season Average Track Error Using The Current Operational and New GFS GFS GFDL
Ops Fcst Parallel Forecast Example Of 5 day Forecast 10 m wind Valid 1 April 2007 NCEP Parallel System ~5 day forecasts from the operational GFS (top left) and the hybrid/GSI GFS (top right) and verifying analysis (bottom) on 1 April 1200 UTC GSI Analysis
Adding TOPEX/Jason-1 satellite altimetry to NCEP GODAS No assimilated data In situ data Assimilated (operational) Operational Plus altimeter Larger correlations between GODAS and Altimeter data in Indian and Atlantic Oceans Smaller RMS errors
In the west, assimilating Argo salinity corrects the bias at the surface and the depth of the undercurrent core and captures the complex structure at 165oE. In the east, assimilating Argo salinity reduces the bias at the surface and sharpens the profile below the thermocline at 110oW. Assimilating Argo Salinity Comparison with independent ADCP currents. ADCP GODASGODAS-A/S
Real-Time Ocean Forecast System Mission • Now • Routine estimation of the ocean state [T, S, U, V, W, SSH]. • Daily 1 week forecast • Every 5 years • Evaluation • Re-initialization • Future • Downscaling support for water levels (with NOS) • Improve ocean interaction in (nested) sub-domains for hurricane forecasts • Support estimates of chemical components (water quality) and organisms distributions in the water (ecosystems) • Improved estimation of the atmosphere state • In short term global forecast • In short term regional forecast
CURRENT RT-OFS Atlantic Description (S1) • State variables: Temperature, Salinity, Velocity, Sea surface elevation. • Primitive equation with free surface. • Horizontal grid: orthogonal, dx/dy~1 • Open boundaries (climatology and tidal model) • Sub-grid scale parameterizations. Vertical and horizontal eddy viscosity and mixing. • Tides, river outflow (USGS, climatology) • Atmospheric fluxes (GDAS, GFS) Dynamical Model (HYCOM)
CURRENT RT-OFS Atlantic Description (S1) • Data: • SST: AVHRR, GOES, In-situ • 2DVAR with vertical projection. • SST: Time interpolated analysis values are nudged during nowcast in the mixed layer. Data Assimilation
CURRENT RT-OFS Atlantic Description (S1)Daily Operations and Product Distribution • Once daily (4Z) • Nowcast 1 day • Forecast 5 days • Grib files for nowcast and forecast • Hourly surface T,S,U,V, SSH, barotropic velocity, mixed layer depth • Daily T,S,U,V,W, SSH for 40 depths • Product distribution • NCO servers (ftpprd) • NOMADS [sub-setting] (full data server functions) • MMAB Web server (ftp, graphics)
Updates (S2) • MODEL ALGORITHMS • Surface initialized Montgomery Potential • Modify boundary condition, giving two invariant external modes • Stabilization of density function (T, p) • Enforced salinity minimum by refreshing the water column • DATA ASSIMILATION ALGORITHM • SST: spatially varying bias removal algorithm • SSH • Assimilation of absolute sea surface height • 2D variational sea surface height, with 1D vertical covariance of sea surface height and layer thicknesses • Reset layer transports preserving momentum • Temperature & Salinity • Assimilation of vertical profiles of temperature and salinity (ARGO & CTD) • 2D variational of density, temperature and layer thickness anomalies • Re-layering preserves volume, momentum; and updated mass and heat
Updates (S2)DATA INPUTS: • Revised vertical grid parameters: • 26 layers, with • higher resolution in the shallow waters • better resolution on the shelf break • better representation of Denmark & Iceland overflows • resolving 4 vertical dynamical modes in major sub-basins • Improved barotropic / baroclinic inputs at open boundaries • Updated Climatology (NCEP – version 6) • Mean dynamic topography (Rio 5) • Historical transports • Revised river inflow data (location and strength) from USGS • Remove noise in net heat flux
GFS+GOCART Offline System • GFS • NCEP/EMC Global Forecast System • GOCART • NASA Goddard Global Ozone Chemistry Aerosol Radiation and Transport Model • Steps • (1) dust modeling • (2) aerosol modeling • Work with NRL (NAAPS)
Jung and Zapotocny JCSDA Funded by NPOESS IPO Satellite data ~ 10-15% impact
Aug. 21, 00Z & Aug. 21, 12Z 120hr 96hr 72hr 48hr 24hr Aug. 19, 06Z
NWW3 Data Assimilation and Future Upgrades • Altimeter data assimilation (above) • 2 way nesting • Coastal applications • Hurricane (moveable nests) • Affordable ensemble forecasting • Improved wave-wave interactions • Parameterized with neural network
MMAB Ice Products Sea Ice Concentration Future Concentration Model Ice Thickness Model Present 25.4 km Resolution Near Future 12.7 km Resolution
The Gulf Stream Wind speed (Knots) 6550 35302520 Warm ring Warm ring North Wall North Wall Slope Waters Gulf Stream Sea Surface Temperature QuikSCAT Winds SST-dependent wind speed difference across the North Wall of the Gulf Stream Gulf Stream Waters – 30to 40 kt Cooler Slope Waters – 15 to 25 kt