Air Force Weather Agency

Transcription

1 Air Force Weather Agency NWP & Implementation of the GSI at AFWA Jay Martinelli 8 August

2 Precision Airdrop Systems Mission Military Operations, USDA, Intelligence Community Crop Production & Soil Conditions Traditional/Special Military Operations Dust/Dispersion Models Space Weather Worldwide Military Operations 2

3 What We Do Numerical Weather Prediction Currently running WRF-ARW in production Began running UKMO Unified Model at the end of 2010 Ensemble Forecasting Air Force Weather Ensemble Prediction Suite Mesoscale Ensemble Prediction Suite 10 member WRF-based Global Ensemble Prediction Suite 62 member NUOPC-based Cloud Analysis Worldwide Merged Cloud Analysis Cloud Predictive Models Short Range Cloud Forecast simple advection method Diagnostic Cloud Forecast based on stats/nwp output 3

4 What We Do Land Surface Modeling Land Information System Partnership w/ NASA, NOAA, NCAR, US Army Dust Forecasting Dust Transport Algorithm (DTA) WRF 15km, WRF 45km WRF-Chem/GOCART dust Global Coverage at 20km / Regional Coverage at 4km Volcanic Ash Modeling Space Weather Modeling Global Assimilation of Ionospheric Measurements (GAIM) Partnership w/ Utah State University 4

5 Historical Air Force NWP 1954: First operational use of NWP by USAF Regional Baroclinic Model 300 km grid; US; 36 h IBM 701: 17,000 instructions per second 1964: Implemented QG-Prediction Model 381 km grid; NH; 72 h 5

6 Historical Air Force NWP 1974: Primitive Equation (PE) Model 381km; 7 vertical levels; NH; 72 h 1986: Advanced Weather Analysis and Prediction System (AWAPS)--Global Spectral Model (GSM) 493km; 14 vertical levels; global; 96 h 1992: Relocatable Window Model (RWM) 93 ~46km; 16 vertical levels; 36 h Quote from one of our AF Tech Notes: This [the computational cost] makes increasing the grid resolution an ineffective way to increase forecaster skill. 6

7 Historical Air Force NWP 1995: Advanced Concept Technology Demo Using MM5 & 14-Node IBM SP2 System Bosnia window run once per day (NOGAPS initialization) 27 km grid; 25 Vertical Levels; 24 h 1999: MM5 18 theaters per day; 80GB/day of model output data; over 90,000 GIF images 7

8 Historical Air Force NWP 1999: Parallelized MM5 and supporting applications-- significant decreases in application run times achieved Added IBM prod system (110 nodes x 4 332MHz) 36/12/4 km grid Spacing; 41 vertical levels; 72 h 2001: Implemented Mesoscale Data Assimilation System (MDAS) Replaced by WRFVAR ~2003 TS Bogusing (improved track & intensity forecasts for TCs worldwide) 2005/6 now: WRF-ARW tested and implemented at AFWA 8

9 AFWA Today $30M Lt. Gen Thomas S. Moorman Building 188,000 square feet 700 personnel (military, civilian, contractor) HQ Staff, two Weather Groups, three Squadrons 24x7 forecast production & reach-back ops 15,000 square foot High Performance Computing Complex 10,248 IBM AIX & HP Linux processors supporting all security enclaves 10.3 TB of actionable weather intelligence transferred to warfighters each day Home to AF s $288M Strategic Weather Center... linchpin enabler of worldwide military ops 9

10 Current WRF Domains UM v7.9 (25km) run at AFWA--used as WRF ICs & LBCs WRF-ARW multiple regional domains 45/15/5/1.67 km; 57 Vertical Levels; 10 mb model top Kain-Fritsch Convection WRF Single Moment-5 Microphysics Yonsei Univ PBL Coupled to Unified NOAH LSM 10

11 Hi-Res WRF Domains Mission-focused domains positioned to help with unique forecast challenges 5/1.67km nested domains designed to hone in on terrain induced features 11

12 Global Ensemble Multi-center Global ensemble prediction suite (GEPS) a 62 member combination of GFS, NOGAPS, and GEM ensembles (example: snow probability graphic) Probability of Six Inches of Snow in 24 hours ending Sun 7 Feb 2009 Example: 174-hour GEPS showed remarkably high probabilities for high-impact snow event given 7-day lead (observed well over six inches in much of DC area) No DA 12

13 Pre-processing Mesoscale Ensemble 20 km Northern Hemisphere/Tropical GFS/GEM/UM member from prior run is used for initial/lateral boundary conditions Model configuration 10 independent model configurations with varying WRF physics and lower boundary conditions (land surface, SSTs) run twice a day No DA 13

14 Mesoscale Ensemble 20 km Northern Hemisphere/Tropical 5-day AFWA hemispheric WRF ensemble forecast. NWS Tuesday afternoon forecast for Saturday: Mostly sunny, no mention of snow. Washington DC received well over one foot of snow, setting many records. No DA Probability of Two Inches of Snow in 24 hours ending Sun 20 Dec 2009 Probability of Six Inches of Snow in 24 hours ending Sun 20 Dec

15 WRF-CHEM Model WRF-ARW plus the Goddard Chemistry Aerosol Radiation and Transport (GOCART) module 4km with inline dust production / transport as part of Air Force Weather Ensemble Prediction Suite (AFWEPS) ~20km hemispheric deterministic with 5 species bin to produce wavelength specific aerosol parameters (e.g., extinction coefficient) No DA GSI 15

16 16

17 4km Deterministic WRF * WRFVAR 17

18 4km MEPS No DA 18

19 4km MEPS 27 April 2011 Tornado Case No DA 19

20 4km MEPS 27 April 2011 Tornado Case No DA 20

21 WRF Data Assimilation (DA) Current Status Data Types Used in the WRF 3DVAR at AFWA Surface (Syn, Airways, METAR, Mobile Synoptic, Ships, Buoys) Upper Air (PIBAL, RAWINSONDE (Ship and Land Launched), Mobile RAWINSONDE, DROPSONDE) Aircraft (AMDAR, ACARS, AIREP, PIREP, RECCO) Feature Track Wind (Cloud drift wind data from using Visible, Infrared, and Water Vapor Channels) SSMIS Sea Surface Wind Speeds and Precipitable Water COSMIC, CNOFS, and METOP GRAS RO Windprofilers (Europe, Japan, US, Korea) Korea/Japan Mesonets (500+/1200+ hourly surface obs) MODIS Polar Cloud Drift wind AFWA Unique observations (classified and unclassified) No Radiance DA 21

22 WRF Data Assimilation (DA) Current Status AFWA has spent the last few years working with NOAA/NCEP/NCAR/DTC (and others) to transition to GSI Phased Implementation of WRF-GSI with direct radiance assimilation capability is currently underway IOC: GPSRO, IASI, AIRS, MHS, HIRS, AMSU-A AFWA working (with NOAA/NCEP support) to community baseline GSI data pre-processing code Little-r to NCEP PrepBUFR w/added quality control Funding an issue 22

23 GSI Data Flow 23

24 WRF Data Assimilation (CY13) First Domains (Global Coverage-WRF) July 2013 Phased transition from WRF-DA to GSI; includes assimilating METSAT radiance data Incrementally assimilate additional satellite data (pending testing) NPP-ATMS, SSMIS, ASCAT, WINDSAT, TRMM-TMI etc 24

25 GC-WRF w/gsi 25

26 WRF w/gsi 26

27 Where we are going Global Coverage WRF Ensemble Today Future < 20 km control ~30 km members North Hemi. Trop. Stripe 38N 25N 38S 25S South Hemi. Enhances and simplifies WRF production Replaces ~80% of our 15-45km WRF domains on UNCLAS 5km domains will be replaced by 4km MEPS while 1.67km domains will remain Full DA on all Ensembles run at AFWA 27

28 Evaluate GSI 3DVAR-Hybrid Data Assimilation Way Ahead Leverage AFWA s existing regional ensemble system Plausibility of using an ensemble of AFWA s Global UM? Assimilate MODIS AOD into WRFCHEM 28

29 Questions? 29