Where We Are and Where Were Going: NCEPs Central Computing System EMCs Numerical Modeling Mesoscale

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Where We Are and Where Were GoingNCEPs
Central Computing System EMCs Numerical
Modeling Mesoscale Modeling
N C E P

• Geoff DiMego
• geoff.dimego_at_noaa.gov
• 301-763-8000 ext7221
• 24 June 2003

Where the Nations climate and weather services
begin
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TOPICS

• NCEPs Central Computing System (CCS)
• What we do with it (current model suite)
• Stuff made for Alaska by Meso Eta, HRW etc
• Latest Bundle of Changes for Meso Eta (8 July)
• What we want to do with it (future plans)
• Weather Research and Forecasting (WRF)
• The North American Regional Reanalysis

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Central Computer System (CCS)

• Initial 3 year base period followed by two 3
  year option periods
• Each three year period contains an upgrade
• Total of 6 major increases through 2010 providing
  guaranteed performance (initially 2.5x then 8x)
  over our current computer
• 70 for use on weather 30 for climate
• Previously 90 for weather 10 for climate
• Installed Sept 02 at IBM Gaithersburg, MD
• Accepted Dec 02, OPS switchover May 03

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Central Computer System (CCS)
Six Increases in Weather Portion of CCS
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Bad News Development has filled its half
Production
Development
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Wx Production Suite Made Up of Four Uniform
Cycles per Day
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NCEP Model Suite-Global
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NCEP Model Suite-Ocean/Waves
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NCEP Model Suite-Regional
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NCEP Model Suite-Regional
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Meso Eta Alaskan Output Grid 21645 km
Polar-stereographic
Contents identical to 40 km CONUS grid 212
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Meso Eta Alaskan Output Grid 21722.5 km
Polar-stereographic
Contents identical to 20 km CONUS grid 215
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Meso Eta Alaskan Output Grid 24211.25km
Polar-stereographic
Contents identical to 12 km CONUS grid 218
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Grids 216, 217 242 MUCH Better Than Original
AWIPS Grids 207214
207, 214
216, 217 242
Except for its vertical longitude which screws up
IPFS NDFD!
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Grids 221 104 Cover Alaska
90 km Polar-stereographic NGM-look-alike
32 km Lambert Full complement
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Grids 243 Covers Eastern Pacific
0.4 deg by 0.4 deg lat-long with content same as
40 km CONUS grid 212
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Map of current BUFR sites in Alaska
49 original
38 new
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Graphics Available from Web Site
http//www.emc.ncep.noaa.gov/mmb/meteograms/
Surface Meteogram
Vertical Time Section
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Nonhydrostatic Mesoscale Model (NMM)

• Model used for runs at grid spacings less than 10
  km Homeland Security, HiResWindow and Fire
  Weather
• See Janjic, Gerrity,and Nickovic, 2001 for model
  equations, solution techniques other test
  results MWR,Vol. 29, No. 5, 1164-1178
• Highly refined version of nonhydrostatic option
  released in May 2000 upgrade to NCEPs
  workstation Eta http//wwwt.emc.ncep.noaa.gov/mmb/
  wrkstn_eta/
• NMM retains full hydrostatic capability
• Incorporate nonhydrostatic effects through ?
  where ?(1/g) dw/dt
• Then split prognostic equations into
• hydrostatic parts plus
• corrections due to vertical acceleration
• Set ? to zero to run in hydrostatic mode

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Nonhydrostatic Mesoscale ModelFeature Comparison
With Meso Eta
Physics (BMJ convection, turbulence etc) have
been tweaked in NMM.
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Hybrid versus Step (Eta) Coordinates
Ptop
Ptop
? 0
Pressure domain
? 0
Sigma domain
? 1
MSL
? 1
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NMM vertical domain compared to Eta
NMM 60 Layer Distribution
18 pressure layers, model top still at 25-hPa
18 layers
1st layer interface above 420 hPa is bottom of
first fixed pressure layer
420 hPa
42 sigma layers between surface about 420 hPa
42 layers
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HiResWindow Fixed-Domain Nested Runs
Alaska Nest AWIPS grid 249

• Users want routine runs they can count on at the
  same time every day
• 00Z Alaska-10 Hawaii-8
• 06Z Western-8 Puerto Rico-8
• 12Z Central-8 Hawaii-8
• 18Z Eastern-8 Puerto Rico-8
• This gives everyone a daily high resolution run
  when fewer than 2 hurricane runs needed

http//www.emc.ncep.noaa.gov/mmb/mmbpll/nestpage/
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Terrain Used in Eta-12 and Eta-10
Eta-12
Eta-10
NMM terrain would not be restricted to discrete
values like the Etas step mountain terrain.
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HRW NMM Alaskan Output

• Grid 249 10 km Polar-stereographic
• BUFR soundings for anonymous ftp from NCEP
  ftp//ftpprd.ncep.noaa.gov/pub/emc/mmb/mmbpll/alas
  ka10.t00z/bufrsnd/
• Output for anonymous ftp from NCEP server
  ftp//ftpprd.ncep.noaa.gov/pub/emc/mmb/mmbpll/alas
  ka10.t00z/
• Output for anonymous ftp from TOC server
  ftp//tgftp.nws.noaa.gov/SL.us008001/ST.opnt/MT.me
  so_CY.00/RD.20030621/PT.grid_DF.gr1_AR.alaska10/
• Web displays of Alaskan Nest (Meso Eta vs
  HiResWindow vs NCAR WRF) On left of page, sweep
  down through parameters, 2-m temperature and 10-m
  wind fields have northern and southern regional
  display options http//wwwt.emc.ncep.noaa.gov/mmb/
  mmbpll/hiresw.alaska10/

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12 km Meso Eta vs 10 km NMM On Web
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12 km Meso Eta vs 10 km NMM vs 10 km WRF On Web
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On Call Emergency Response

• SDM receives request for run with specs of
  release and initiates run into production where
  it may preempt existing or future production runs
• 4 km NMM run produces hourly output
• Hourly output drives 4 km HYSPLIT run to describe
  atmospheric spread of hazardous material
  (designed for radiological accidents)
• HYSPLIT output sent to WFO emergency managers
• No output of the NMM meteorological fields (yet)

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26 Selectable 4 km domains for homeland security
response
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Fire Weather / IMET Support Run

• SDM receives request for run via coordination
  call with Boise, WR, SPC etc.
• Runs are made within dedicated run slots at 00z,
  06z, 12z and 18z running over the top of the Meso
  Eta
• 8 km NMM run produces 3 hourly output grids
• Output grids (look just like HiResWindow) picked
  up by WR, clipped to relevant subregion and
  prepared for transmission to the IMET laptops
  using same FX-NET procedure developed for
  Olympics. SPC gets grids directly.

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26 Selectable 8 km Domains For Fire Weather /
IMET Support Identical To 4 km Homeland Security
Domains
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Fire Weather / IMET Run Output

• The firewx grids are available out to 48 hours on
  the TOC ftp server (tgftp.nws.noaa.gov) under the
  following format
• /SL.us008001/ST.opnl/MT.nmm_CY.CC/RD.YYYYMMDD/
  PT.grid_DF.gr1_AR.nestxx where
• CC 00, 06, 12, or 18
• YYYYMMDD the current date
• xx 01 - 26 (geographic location)
• Filenames follow the convention
• fh.hhhh_tl.press_gr.awpreg (hhhh 0000, 0003,
  0006, ... , 0048)

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Sample GIF File Denoting Area of Fire Wx Run
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8 km versus 4 km Hybrid Terrain
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12 km Meso Eta vs 8 km NMM Winds
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12 km Meso Eta vs 8 km NMM Winds
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Alaska Case Eta-12 vs NMM-417 March 2002
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Alaska Case Eta-12 vs NMM-417 March 2002
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http//wwwt.emc.ncep.noaa.gov/mmb/SREF/SREF.html
This page will add Alaskan products by October
2003
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Implementation ofEta Upgrade Bundle
N C E P

• Geoff DiMego
• geoff.dimego_at_noaa.gov
• 301-763-8000 ext7221
• 18 June 2003

Where the Nations climate and weather services
begin
41
Planned Changes to Eta-12

• Upgrades to Gridscale cloud precipitation (Brad
  Ferrier)
• Begin proper cycling of total condensate (Eric
  Rogers)
• Upgrade microphysics and improve cloud -
  radiation interaction
• Upgrades to 3DVAR analysis (Dave Parrish)
• Add direct analysis of WSR-88D radial velocity
  from NWS Multicast
• Upgrade radiance processing, stop thinning, use
  NOAA-17 (20x increase)
• Upgrades to Precipitation assimilation (Ying Lin)
• Assimilation of GOES cloud top pressures (w/ Jim
  Jung)
• Assimilate hourly precip from Stage IV instead of
  Stage II
• Extend off-time (06z 18z) runs to 84 hours
  (Eric Rogers)
• Increase output in both frequency and content
• http//wwwt.emc.ncep.noaa.gov/mmb/mmbpll/etapllsup
  12.etax/
• http//wwwt.emc.ncep.noaa.gov/mmb/tpb.spring03/tpb
  .htm

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Sample Total Cloud Cover
Better due to reduced longwave cooling
Before Changes
After Changes
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Sample Distribution of Processed 88D Radial
Velocity Data
5 km processing of an hours worth of scans
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Sample Cloud Top Pressure Field
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All NWS RFCs Stage III are used in Stage IV
except AKRFC NWRFC
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Example of new fields postable from Eta
Cloud Water
Cloud Ice
Rain
Snow
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Baldwin Type versus Precip Type Direct from Model
Baldwin Diagnosed Precip Type
Percent Frozen Direct from Models


Gridscale Scheme
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Bundle Verification Results 24hr QPF
ETS
BIAS
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Surface Temperature Response
True for East and West for both 00z and 12z runs.
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Bundle Verification Results Sfc RH
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Bundle Verification Results Upper-Air
24 hr
T
Z
RH
V
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Bundle Verification Results Upper-Air
60 hr
T
Z
RH
V
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PLANS FOR THE FUTURE

• For each of the possible six upgrades/phases of
  the CCS contract with IBM

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Global Forecast System (GFS)
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Ensemble Forecasts
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North American Early Guidance System
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Planned 15 Expansion in 2005
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Hi Res Window OCER
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Total Generated by Models at NCEP

• Model Plans Linked To AWIPS
• First iteration complete
• Connect model upgrade plans to a (conservative)
  set of proposed AWIPS product upgrades -ALASKA
  INCLUDED
• Presented to NWS/OCWWS folks at meeting 10
  September
• No second iteration to date.

Total Transmitted on AWIPS (PROPOSED!)
Ratio of Generated at NCEP to Transmitted on AWIPS
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Why Cant We Do Better?

• Numbers just don't get us there - weather portion
  of computer in 2010 is 36x of present capability.
  If all this is used to increase horizontal
  resolution alone
• Take the cube root (x,y,t) of that 36 which is
  3.3
• For Meso Eta 12km / 3.3 3.63km highest
  resolution possible
• NO ALLOWANCE for ANY other upgrades (domain,
  forecast range, vertical resolution, 3DVAR or
  cost due to additional data sources like radar or
  satellite, physics upgrades or implementing or
  increasing membership of ensembles).
• Getting a bigger machine is unlikely since
  current talk describes FY2004 budget as being
  extremely LEAN.
• Nesting degrades results.

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Weather Research and Forecasting (WRF)

• End-to-end Common Modeling Infrastructure
• Observations and analysis
• Prediction model
• Post-processing, product generation and display
• Verification and archive
• For the community to perform research
• For Operations to perform NWP
• USWRP sponsorship - many partners NCAR, NCEP,
  FSL, OU/CAPS, AFWA, FAA, NSF and Navy
• Initial implementation in HiResWindow in 4QFY04
• Ensemble approach to be taken instead of
  single-run deterministic approach

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Accelerates NWS towardWRF SREF end-state
objective
Prediction Model Diversity
Initial Condition Diversity
Dynamic Core 1 Dynamic Core 2 . . . Dynamic Cor
e N
Dynamic Core 1 Dynamic Core 2 Dynamic Core N
DA
Init
S R E F
Global ESMF
1
1
2
2
3
3
N
N
NOAH Convective Boundary
Radiation Land-sfc Schemes Layer
Schemes
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NCEP WRF Ensemble Design

• In June 2004, computer increase will total 6x
• Therefore, establish 6-member ensemble run in
  place of single HiResWindow run
• 2 Control members
• NCEP NMM core NCEP physics, Dx 8 km
• NCAR Mass core NCAR physics, Dx 10 km
• 4 Additional members
• alternative physics or bred mode initial
  condition perturbations
• Qualify cores and evaluate potential ensemble
  members according to the WRF Test Plan

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Example of Ensemble Probability Product
CAPE gt 1000j/kg Prob
0-6km Shear gt40kts Prob
Conv Precip gt0.01 Prob
Severe Convection Prob
Courtesy NOAA-SPC
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WRF Test Plan for Summer 2003

• Participants NCEP, NCAR, FSL, AFWA/NAVO-MSRC
• Two Cores NCAR mass core NCEP NMM core
• Two physics suites NCAR suite NCEP suite
• ICRUC and Eta each with bred perturbations
• BCEta with SREF-based anomalies
• Retrospective Runs2 nests for 30 days in 4
  seasons
• - Aug/02 Central West - Oct/02 Alaska East
• - Feb/03 West East - May/03 Central East
• Real-time Runs at NCEP Human Forecaster Feedback
• 2 nests for 6 weeks each
• Jul/Aug West East
• Aug/Sep Alaska Central

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North American Regional Reanalysis
Office of Global Programs
N C E P
Where the nations climate and weather services
begin
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Domain Coverage of NARR
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190 km
32 km
For the Eta, a 32 km run takes 178 times the work
of a 190 km run!
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NARR GOAL To Improve on NCAR/NCEP Global
Reanalysis

• Higher resolution 32 km vs T-62 (180 km)
• More frequent updates ouput 3 hr vs 6 hr
• Add precipitation assimilation
• Add satellite radiance assimilation
• 25 year period 1979-2003
• To be perpetuated by NCEP/CPC like CDAS
• Production ongoing on NCEPs old IBM
• Completion expected in Fall 2003
• Could be source for 2.5 km downscaled climatology
  for use in NDFD and IFPS techniques

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Downscaling Strategy - A

• Correct model bias (on model grid)
• Todays forecast vs current model history (1-2
  months)
• Current ensemble mean vs Reanalysis climate mean
• Correct model spread (on model grid)
• Todays forecast vs current model history
• Current ensemble spread vs Reanalysis
  climatological spread
• Apply corrections to all ensemble members
• Result forecast anomaly on model grid, corrected
  for climatology
• Calculate most probable anomaly from ensemble
  (error weighted mean)
• Given high resolution, gridded climatology for
  each forecast element
• Add most probable anomaly to climatology for
  downscaled forecast element
• Not guaranteed to be physically consistent (like
  model grids)
• Forecast anomaly on model grid needs to be
  transmitted
• High resolution climatology resident at WFOs

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Downscaling Strategy B

• Bias correction directly on NDFD grid
• High resolution information still needed from
  local climatology
• Can be done locally or centrally
• If locally, assumes WFOs receive all ensemble
  forecast members
• Neural Network application
• Input ensemble forecasts, lat, lon, elevation,
  climatology etc
• Output bias corrected ensemble forecasts on NDFD
  grid
• Penalty function probabilistic measure (e.g.
  Brier Skill Score)