J9.4. Asheville, North Carolina 3 NASA Goddard Space Flight Center, Greenbelt, Md. Water Management, Bucharest, Romania 1.

Transcription

1 J9.4 An End-t-End Hydrmeterlgical Frecasting System Jhn N. McHenry 1, Gregry S. Wilsn 1, Knstantine P. Gergakaks 2, Christa D. Peters-Lidard 3, and Mariusz Matreata 4 1 Barn Advanced Meterlgical Systems, Asheville, Nrth Carlina 3 NASA Gddard Space Flight Center, Greenbelt, Md. 2 Hydrlgical Research Center, 4 Natinal Institute f Hydrlgy and Water Management, Bucharest, Rmania 1. INTRODUCTION Barn Advanced Meterlgical Systems, in cllabratin with Lckheed Martin Crpratin, the Hydrlgic Research Center, the US Natinal Weather Service Office f Hydrlgy, and researchers at NASA and the Natinal Institute f Hydrlgy and Water Management (NIHWM) in Bucharest, Rmania, have develped an end-t-end hydrmeterlgical frecasting system. The system relies upn gauge-crrected hurly t subhurly Dppler-radar-based QPF estimates supplying inputs t advanced hydrlgical mdel frecast systems. Numerical weather predictin mdels cmprise additinal, lnger-range elements f the frecast system. Fr larger-scales, the NWSRFS (Natinal Weather Service River Frecast System), using the Sacrament Sil Misture Accunting Mdel (SAC/SMA) and apprpriate river/stream ruting, is used t detect and frecast river fld/stage. Nested within this, the cntributins frm upstream higherrder basins are estimated with the TOPLATS mdel running as a land-data-assimilatin system (LDAS). Bth mean-areal precipitatin estimates (needed fr the SAC/SMA mdel) and very high reslutin estimates (needed fr the fully distributed TOPLATS mdel) are derived frm the netwrkedmsaic Dppler system. The system als includes a flash-fld guidance cmpnent, in which sil-misture deficits are estimated frm either the SAC/SMA mdel r the TOPLATS mdel. The deficits are used tgether with up-t-date (1 hr, 3hr, 6hr, and 12hr) precipitatin ttals t estimate the amunt f additinal precipitatin needed fr streams t reach bankful. Our system is unique in that it is cmprised nt nly f the mdeling cmpnents including a fully distributed hydrlgical mdel, but f the radarhardware and interpretatin sftware needed t drive the mdels: that is, it is a cmplete end-t-end * Crrespnding authr address: Jhn N. McHenry, Chief Scientist, Barn Advanced Meterlgical Systems, jhn.mchenry@barnams.cm. Phne: (919) ; Fax: (919) system that may be deplyed anywhere in the wrld. 2. SYSTEM OVERVIEW AND EXAMPLE: DESWAT The Destructive Water Abatement and Cntrl f Water Disasters (DESWAT) prgram, recently authrized by the Rmanian gvernment, is the first example implementatin f the end-t-end system as it becmes functinal ver the next three years. DESWAT was established as a fllw-n t the SIMIN (Natinal Integrated Meterlgical System, Iana, et al., 2003) prject, which integrated weather radars, autmated weather bservatins statins, lightning detectin netwrks, satellite data acquisitin, NWP mdels, buys, and frecaster decisin/display systems using varius telecmmunicatins platfrms in Rmania. DESWAT mves beynd this by accessing the SIMIN data as inputs t a river/stream and flashfld frecast decisin supprt system. The main bjectives f the DESWAT prject are: Upgrade the hydrlgical mnitring system: Upgrade hydrmetric sensrs and data cllectin - autmatic statins: abut 600 statins with water level, air and water temperature and precipitatin sensr. abut 70 statins - with water quality sensrs (disslved xygen, cnductivity, ph, turbidity, etc). Enhance the cmmunicatin system between the upgraded hydrmetric sensrs and the NIHWM using tw frm the fllwing systems: radi data transceiver mdule supprting vice and data GSM mbile telephne using SMS satellite Data Cllectin Platfrm transmissin

2 Deply hydrlgical data integratin sftware capable f: Ingest and analysis f a massive vlume f data frm varius surces: weather and hydrmetric statin sensrs, radars, satellites. Interpret quickly all these data using imprved river frecast mdels. Generate frecast prducts. Deliver the frecast prducts t the public and t the decisin makers in fld defence. Figure 1 shws a cnceptual verview f the DESWAT system (withut the sensr detail) as it was envisined in June f 2003; nly minr changes have been made at this time. 2.1 Natinal Hydrlgic Radar Prcessing System (NHRPS) diagram as the Natinal Hydrlgic Radar Prcessing System (NHRPS), features the integratatin f sparsely spaced surface hydr- and meterlgical-type measurements with high-spatial reslutin remtely sensed radar imagery. This includes integratin f the prducts frm five (5) WSR-98D S-Band weather radars prvided by SIMIN, and fur (4) legacy C-Band weather radars integrated by SIMIN. Thus all nine (9) radars in the Rmanian Natinal Radar Netwrk are integrated int the Hydrlgical prcessing. The NHRPS perfrms this functin in real-time using fur separate but linked prcessing applicatins; C-Band Radar Prduct Generatr, HydrFutureScan, Hydr COBRA, and Rain Gauge Bias. C-Band Radar Prduct Generatr. The C-Band Radar Prduct Generatr (RPG) systems are used t generate fundamental radar parameters frm the legacy C-Band radars t allw the integratin f new SIMIN radar data with these existing systems. The SIMIN-based cmpnent, shwn in the Figure 1. High-level cnceptual diagram f the DESWAT end-t-end hydrmeterlgical frecasting system HydrFutureScan. HydrFutureScan systems are used t prject individual radar imagery int the future taking int accunt advectin, grwth and decay, allwing fr an accurate 0-2h quantitative precipitatin frecast (QPF). Figure 2 shws an example f a single predictin f reflectivity fr a cnvective strm mving sutheastward thrugh the Central US.

3 Reginal FutureScan Precipitatin Frecasts Figure 2. Example HydrFutureScan reflectivity fr a strm mving sutheastward acrss the Central US.. HydrCbra and Rain Gauge Bias. The HydrCbra cmpnent is used t derive hydrlgic prducts frm the individual radar base data. These prducts include, but are nt limited t, 1h, 3h, 6h, and 12h strm ttal precipitatin estimates updated every 5 minutes, quantities required fr inputs t the peratinal hydrlgical mdels (Figure 3 belw) Further, DESWAT will fully implement a rain gauge bias crrectin system, which will be used t crrect the radar estimates f precipitatin rate and accumulatins based upn realtime surface rain gauge measurements. Figure 4 shws an example f rain gauge measurements made ver a cunty regin that are btained in real-time t adjust the radar estimates t a higher accuracy. Figure 5 shws the results f apply these measurements t a multi-radar cverage pattern prducing highly accurate quantitative ttals and spatial cverage. Barn Advanced Hydrlgic Prducts Real-time, High Reslutin Radar Prcessing Perfrmance fr Flding and Winter Precipitatin Natin-Wide COBRA Real-time 1,3,12 & 24 Hr Ttals Every 5 min. at 1Km Real-time Rain Gauge Biased 1 Hr QPF Every 5 min. Figure 3. Example incremented strm ttal precipitatin QPE prducts. Figure 4. Example rain-gauge netwrk used t bias-crrect radar-derived QPEs. Lwer Clrad 24 Hur 1 Km Multi-Radar, Gage-Biased Ttal Figure 5. Example rain-gauge adjusted radar rainfall estimate ver the Lwer Clrad River in SE Texas. 2.2 Barn Hydrlgical Frecast and Mdeling System (BHFMS). The majr cmpnents f the Barn Hydrlgical Frecast and Mdeling System were mentined in the Intrductin. A high-level diagram depicting its cnfiguratin fr DESWAT is shwn in Figure 6. In this diagram, elements f the BHFMS are brken int functinal cmpnents. The left-hand side f Figure 6 depicts the River-Stream Frecast Cmpnent (RSFC), while the right-hand side depicts the Flash Fld Frecast Cmpnent (FFFC). Within the RSFC, the traditinal lumped mdeling apprach (RSFC-L), driven by meanareal precipitatin and represented by the NWSRFS and all f its cmpnent mdels, is shwn n the left-hand side. On the right-hand side f the RSFC are the distributed mdels (Barn Land Surface

4 Hydrlgy Mdels (BLSHM), represented by versins f the TOPLATS (Peters-Lidard, et al., 1997) and NOAH (Sridhar et al., 2002) land-surface hydrlgy mdels. In additin, the emerging NWS Distributed Mdeling System (NWSDMS 2.0) is shwn as an ptin. RSFC NWSRFS NWS DMS 2.0 TOPLATS NOAH HFMS FFG FFFC RSFC-L RSFC-D FFFC-S FFFC-D BLSHM Figure 6. Barn Hydrlgical Frecast Mdeling System On the right-hand side f the verall system, the FFFC is shwn, als with tw branches. On the left-hand side f the FFFC branch, the semidistributed (FFFC-S) flash-fld frecast system (Gergakaks, 1997, 2004) is shwn, with a bx nting that the primary utput is the flash-fld guidance (FFG) number. On the right-hand side f the FFFC, a fully distributed (FFFC-D) augmentatin is shwn in which the BLSHM distributed hydrlgy mdels are used t calculate sil-misture deficits needed t prduce higher-reslutin FFGs. The BLSHM implementatins n bth sides f the diagram will be implemented as Land-Data Assimilatin Systems (LDAS s) using the SIMINderived QPE. Frecast QPF frm ne f the Rmanian NWP mdels, prbably the ALADIN mdel, will be used t predict evlutin f the sil misture fields 2-60 hurs int the future. 2.3 Natinal Hydrlgic Archiving System BLSHM TOPLATS NOAH The Natinal Hydrlgic Archiving System (NHAS), shwn in the lwer-left hand f Figure 1, will allw event recnstructin and analysis. Data frm the Natinal Hydrlgic Radar Prcessing System and the Barn Hydrlgical Frecast and Mdeling System are archived fr pst strm analysis t cntinually imprve the existing and newly prvided advanced surface hydrlgic and atmspheric mdels. 2.4 Interactive Display Systems fr Decisin Supprt Interactive display systems fr use in decisinsupprt are shwn n the right-hand side f Figure 1. HydrThreatNet wrkstatins and supprting servers allw users t view all the prducts frm the NHRPS and NHPS elements interactively in realtime dwn t the street level and fr the entire cuntry. HydrNet Briefing Statins allw remte user access t the real-time quick-lk analyses f the key hydrmeterlgical parameters ver any prtin f the cuntry, dwn t the street level. These are primarily fcused n real-time water management and emergency fld/severe weather warnings. Natinal Flash Fld alerts are prduced and transmitted autmatically by the SAF-T-Net alerting system via cell phnes, pagers and . Finally, the Natinal Msaic Hydr Server (NMHS) cmbines all the meterlgical and hydrlgical infrmatin frm multiple radars and surface data int cuntrywide digital image prducts fr analysis and display as well as transmissin t reginal hydrlgic service centers. 3. CONCLUSIONS During the next three years a new hydrlgical frecast and warning system will be implemented at the natinal level in the framewrk f DESWAT prject (Destructive Water Abatement and Cntrl f Water Disasters). As part f DESWAT, the Barn Hydrlgical Frecasting and Mdeling System relies upn gauge-crrected hurly t sub-hurly radar-based QPF estimates supplying inputs t advanced hydrlgical mdel frecast systems. Numerical weather predictin mdels cmprise additinal, lnger-range elements f the frecast system. Fr larger-scales, the NWSRFS (Natinal Weather Service River Frecast System), using the Sacrament Sil Misture Accunting Mdel (SAC/SMA) and apprpriate river/stream ruting, is used t detect and frecast river fld/stage. Nested within this, the cntributins frm upstream higherrder basins are estimated with the TOPLATS amd NOAH mdels running as a land-data-assimilatin system (LDAS). Bth mean-areal precipitatin estimates (needed fr the SAC/SMA mdel) and very high reslutin estimates (needed fr the fully distributed TOPLATS mdel) are derived frm the netwrked-msaic radar system. The system als includes a flash-fld guidance cmpnent, in which sil-misture deficits are estimated frm either the SAC/SMA mdel r the TOPLATS mdel. The deficits are used tgether with up-t-date (1 hr, 3hr, 6hr, and 12hr) precipitatin ttals t estimate the amunt f additinal precipitatin needed fr streams t reach bankful. The system represents a state-f-the art river stage, fld, and flash-fld frecasting system whse first implementatin will be within the Rmanian DESWAT prgram. The develpers

5 anticipate that the new system will allw the Rmanian NIHWM t prduce significantly mre accurate hydrlgical frecasts under imprved ntificatin and alert capability. REFERENCES Gergakaks, K.P., 2004: Analytical Results fr Operatinal Flash Fld Guidance, Jurnal f Hydrlgy, submitted. Gergakaks, K.P., Guetter, A.K., and J.A. Sperfslage, 1997: Estimatin f Flash Fld Ptential fr Large Areas. Destructive Water: Water-Caused Natural Disasters, their Abatement and Cntrl. G.H. Leavesley, H.F. Lins, F. Nbilis, R.S. Parker, V.R. Schneider, and F.H.M. van de Vn (eds.), IAHS Publ. N. 239, IAHS Press, Wallingfrd, UK, Iana, M., V. Ivanvici, E. Crdneanu, D. Banciu, A. Apstu, and B. Frd, 2003: SIMIN The Integrated System fr Meterlgical Surveillance, Frecast, and Alert in Rmania. Online Reference: Peters-Lidard, C. D., M. S. Zin and E. F. Wd, 1997: A sil-vegetatin-atmsphere transfer scheme fr mdeling spatially variable water and energy balance prcesses, J. Gephys. Res., 102 (D4), Sridhar, V., R. L. Ellitt, F. Chen, and J. A. Brtzge, 2002: Validatin f the NOAH-OSU land surface mdel using surface flux measurements in Oklahma, J. Gephys. Res., 107(D20), 4418, di: /2001jd