Spatial ad Temporal Trackig of Ocea Wave Systems Adré va der Westhuyse (with thaks to Jeff Haso ad Eve-Marie Devaliere) The WAVEWATCH III Team + frieds Marie Modelig ad Aalysis Brach NOAA / NWS / NCEP / EMC NCEP.list.WAVEWATCH@NOAA.gov NCEP.list.waves@NOAA.gov Wave trackig 1/19
Outlie Covered i this lecture: Partitioig ad trackig algorithms Criteria for combiig ad trackig sytems Idealized cases Field cases: North Pacific Hawaiia Islads U.S. West Coast WFO Los Ageles Coclusios ad future work Wave trackig 2/19
Backgroud: Wave systems Trackig of ASAR swell i the Pacific NWS coastal forecast domais http://www.esa.it/esaeo/sem563aatme_idex_0.html Wave trackig 3/19
Partitioig of spectral model output Partitioig of wave spectra - Gerlig (1992) - Hasselma et al. (1994, 1996) - Haso & Phillips (2001) - Portilla et al. (2009) (Tracy et al. 2007) (Haso & Phillips 2001) (Haso & Phillips 2001) Wave trackig 4/19
Trackig of spectral model output Lad Correlatio of partitios i space ad time: - Cotiuity of parameters (Voorrips et al. 1997; Haso & Phillips 2001; Devaliere et al. 2009) - Source idetificatio (Aares & Krogstad 2001; Delpey et al. 2010) Sea (Tracy et al. 2007) (Devaliere et al. 2009) Wave trackig 5/19
30-yr WW3 hidcast based o CFSR wids (Chawla et al. 2013) Wave trackig 6/19
Spatial variatio of DIR p ad T p CFSRR-WW3 4 arc-mi, 3h hidcast, over 2007-2008 NDBC 46213, 46047, 41012, 41014 Dir p T p 5s 7s 5s 7s 9s 11s 9s 11s 13s 15s 13s 15s 17s 19s 17s 19s Wave trackig 7/19
Versio 1.1, Feb. 2013 Wave trackig 8/19 WW Witer School 2013 Loop 1: Likig poits to systems: where: ad: = 10 o, T = 1 Loop 2: Combiig systems: Combie if system eighbors differ by less tha ΔT ad Δ, with Δx = 1 arc-deg Criteria for spatial trackig ΔT p /1 arc-deg. Δ p /1 arc-deg. Lad Sea No eighbors! 2 0, 0 2, 2, ~ ~ ~ i m m i p p i p p i H H H T T T GoF x m x m T T 2 1 10 63.2, ~ 3.65 max 0.6 3.69, ~ 0.346 max, 2, 1 i p i p T m T m
3 Criteria for temporal trackig 1) Mea period over system Ts m1x T, x 1 arc deg ~ s m1 max 0.346 T p, i 3.69, 0.6 Settig: T = 1 s Sys t-1,j 2) Mea directio over system s m2x, x 1 arc deg ~ s m2 max 3.65T p, i 63.2, 10 Settig: = 10 o 3) Spatial overlap of systems: i, j Sys t,i GoF i, j ~ T s p, t, i ~ T T s s p, t 1, j 2 ~ s p, t, i ~ s s p, t 1, j 2 N t 1, j 0.5N t 1, j i, j 2 Wave trackig 9/19
Program flow ww3_systrk (mai program) wavetrackig (read spectral partitio iput) spiraltrack Parallel regio t=1 t=2 t=3 t= timetrackig Wave trackig 10/19
Idealized cases (wedge, plus islad) Sys1 Sys2 Sys3 Hs T p Hs T p Wave trackig 11/19
30-yr WW3 hidcast based o CFSR wids Wave trackig 12/19
North Pacific, 30 arc-mi grid 14 April 2009, 10:00 Raw partitioed data Spatially tracked systems Hs Tp Hs Tp Wave trackig 13/19
North Pacific, 30 arc-mi grid 14-18 April 2009 Wave trackig 14/19
Hawaiia Islads, 10 arc-mi grid 14-18 April 2009 Wave trackig 15/19
U.S. West Coast, 10 arc-mi grid 14-19 April 2009 Wave trackig 16/19
WFO Oxard, 2 arc-mi grid 7-12 Ja 2012 Wave trackig 17/19
Coclusios & Future work 1. Spatial ad temporal trackig post-processig available as WW3 subprogram ww3_systrk (see Va der Westhuyse et al. 2013). 2. Spatial variatio of T p ad Dir p determied from 2 years of CFSRR-WW3 wave climate data. 3. Verified for idealized cases ad field cases at various scales (30-yr CFSRR-WW3 wave climate, WFO domais). 4. Future: Depth depedece i shallow water? 5. Future: Extesio to ustructured grids Wave trackig 18/19
Refereces Aares, J.E, ad H.E. Krogstad, 2001. Partitioig sequeces for the dissectio of directioal ocea wave spectra: A review, techical report, SINTEF Appl. Math., Oslo. Chawla, A., D.M. Spidler, H.L. Tolma, 2013. Validatio of a thirty year wave hidcast usig the Climate Forecast System Reaalysis Wids. Ocea Modellig, i press. Delpey, M.T., F. Ardhui, F. Collard ad B. Chapro, 2010. Space-time structure of log ocea swell fields. J. Geophys. Res. 115, C12037, doi:10.1029/2009jc005885. Devaliere, E.-M, J.L Haso ad R.A. Luettich, Jr., 2009. Spatial trackig of umerical wave model output usig a spiral trackig search algorithm, Proc. 2009 WRI World Cogress o Computer Sciece ad Iformatio Egieerig, Los Ageles, CA, Vol. 2, 404 408. Gerlig, T.W., 1992. Partitioig sequeces ad arrays of directioal ocea wave spectra ito compoet wave systems. J. Atmos. Oceaic Techol., 9, 444 458. Hasselma, S., K. Hasselma, ad C. Bruig, 1994. Extractio of wave spectra from SAR image spectra. Dyamics ad Modellig of Ocea Waves, G. J. Kome et al., Eds., Cambridge Uiversity Press, 391 401. Hasselma, S., C. Bruig, ad K. Hasselma, 1996. A improved algorithm for the retrieval of ocea wave spectra from sythetic aperture radar image spectra, J. Geophys. Res., 101, 16,615 16,629. Haso, J.L. ad O.M. Phillips, 2001. Automated aalysis of ocea surface directioal wave spectra. J. Atmos. ad Ocea Tech., Vol. 18, 277 293. Portilla, J., F. J. Ocampo-Torres ad J. Mobaliu, 2009. Spectral partitioig ad idetificatio of wid sea ad swell, J. Atmos. ad Ocea Tech., Vol. 26, 107 122. Tracy, B, E.-M. Devaliere, J.L. Haso, T. Nicolii ad H.L. Tolma, 2007. Wid sea ad swell delieatio for umerical wave modelig, Proc. 10th It. Workshop o Wave Hidcastig ad Forecastig, Paper P12. Voorrips, A.C., V.K. Maki, ad S. Hasselma, 1997. Assimilatio of wave spectra from pitch-ad-roll buoys i a North Sea wave model. J. Geophys. Res. 102, 5829 5849. Va der Westhuyse, A.J., J. Haso ad E.-M. Devaliere, 2013. Spatial ad temporal trackig of wave fields from ocea basi scales to coastal waters. J. Atmos. Oceaic Techol., i review. Wave trackig 19/19