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tamh tm iedor sphere -1 el 9a8 ti 0vse , lyc li s m im a p te le models. Much more detailed than in the Australian region (Simpson and Downey 1975; run. Rather they are models than simp allysofomuuscehdm ro ourte in eelxypesn in si cvee th to e V ha osicbe ee anndfoH rc uendt 198 recasting El Nino behav tures for the p w er iitohd4o ). bsT1eh rv e BMRC climate model iour (e.g., sea surface temperatures in the east simulated by the model ha 9s49e -d 9 1 se , aasnud rf ac th eet em ra p in efraal lfeoqrueactaosrti al r Pacific), they could, in theory, be used to ob been compared with the coupling o ai fnftahleloacnedantetmoptehrea tu artemoosvpehre re la nidn . th Tehseew te asse rv ru end ra fiinvfea ll t i ( m Fr eesd , er w ik istehne th teal. s1a9m9e5 ). seTahesm ur o fa dceelmmo od deellss , ( hPoowweevrere , tis less than perfect. Improved ocean ph m er p ic e ra ctoun re d s it io bnust . s T li h ghtly different starting atmos these coupled mode alls . . 1995) are being developed for ialg lu rseterm ate esnttw he it h ‘ noobisseer ’ veind iffe ed rtahier ence betw nfa m ll, o w de e l . neTeoenge th t e ed to av mru uns O era cghep se aarsto ne pro onfalthperebd le ic m ti own it ihstthheeduisfef ic oufltcy oupled models in all five runs as an ‘ens coupled models has in sitmhue la attim ng osrp ai hnefrailclA of u st p ra rleicainpp it raetc io ip n i tat sihoon, w em abtls le’. eoam st e The en o ve srkin ll sem o rt ihne bl sei ave rn Amuusl rag t a ra ti lnegsgoennte he ia. (Ni ra l sp su a c ti caelsssca in le ssiimmuploartt in an gtaftomrousspeh rs e , ridcesvpairtieab th il e it iyr Fur T th h e es resoau tm th o , stphheem ri odels are less successful. sea cshuo rf l a ls ce1t9e9m6p ) e . ra M tu ordeealneoxmpaelriiemsehnatvsewailtohngspheicsitfo ie ry djtohb er e o fo f re si m pr uolbaa ti bnlgyc th cemSoOdIel ( eFx ig pe urrieme3n .3 ts ) . do ThaegSoO od I an be predicted without the need
te a c ri hanbiiq li ues draw on many aspects of recorded past cast skill is that the statistical techniques generally cao ss r o re cliaattie ty d w in i th thEeNS cl O im . aItne system, not just those perform poorly in northern spring, with cross forecasts o , nanaunmd be mruo lt fipo le ad li dnieta io r n to simple linear validated anomaly correlations <0.6 for forecasts even operational use. These ttohoelrssitn at c i sti rceagl re to ss oilosn -a braes ed just one season ahead and <0.3 for forecasts two antianalogs (Livezey lude analogs an idnd se aam so pnesdapheerasd is . te S n im ce p l ( eapceorm sis btiennacte io onfo th fepeSrS si Tss te , nocrethaenidrCClain mate Normals ( OaC nd N ) B a ( r H ns utaonng 19 e8t8a ), l . O1p9 ti 9m4a ) l , tcilm im eao to fltohgeyy ), easrh . ow just as much, or more, skill at this l P in re eio se n n ic d al Correlation Analysis (CCA) (Barnett and Even if the statistically based SST forecasts were War adrda is ocrrfiemr in 1a9n8t7a ) n , a ly asnids (M eig a e ry novnecatnodrSatnoarleyy si s19a8n5d , p th earn fe -c pte , rf heocwtreevlear ti , o n th sh e ip hsisbteotrw ic eaelnrS ec SoTrda no sh moaw li sesla es nsd -d beav se e d lo ponndnFeoulrlaalndne1 tw 99 o 1). More complex methods precipitation even for regions with a strong ENSO skill scor eedso (e f . g o . p , er Lao ti nognaertksal. ha1v9e also recently been influence. In such regions, precipitation anomalies these tools has been mar lgpirneacl ip in it 9a7 ti ) o . nIn fo general, the typically show a consistent ENSO relationship in 75-much more skilful in parts of the t h tr eopeixc tr raetcrao sts using 80 per cent of the ENSO episodes this century. How et al. 1993). In the extratropics, statist s ic a (e l .g p . i , cWsba ut ever, even the best performing statistical SST pre offer little encouragement for more reliable m dr e o th uogd rd s b di e c tw tio enen sc ohbes mes have ht Pacific SST oefrv0e .8 d -0 a .9 ndcp ro re sds-ivca te li for two se d d ate aso t n ro dspa ic caolr re e la atsitoen rn s p cu re r d re ic nttiosn ta steexocfepEtNwShOenoursw ed it h in EcNoS nj Ounfcotrieocnasw ts i th (e . tgh . e , n co orrrtehleartn io nsuomfm th er e through fall. Thus if th hee ad an ionmtahleysB ta atrin st sitcoanldarnodu gh Stmp it rhe di 1c9 ti 9o6n ) . t ha Wter el nao te w s to fo cEuNsSoOn , m th ieghotbr served SST igs iv 0 e . n8irnegs io tr noanlgpE re N ci SpO ita tyieoanrsw , w ith e a in ndpatrh ti ecuplraerd . iction of central and eastern Pacific SST pitation eawsio th na abn ly o m ex a p ly ecctotrorem la atk io e such year nps re odfi0 ct . i6o -n 0 s . 7ofdpurreicnig icsorcro el nastiisosn -o i v .e e . r , a in ll aybeo ar ustwhialllfboefsau ll byse ta a n rs t . iaT ll hyeleasvse ; rtahgies tent with experience (Barnston and Smith
tcoourpulnedexopceenasn iv -a etm en ossepmhbelrees . mIofdseol , s w to ecpo re u d ld ic tuslea rg th e e -l doiscst . i on Tsh , ebasskeid ll in seasonal rainfall and f scale indices such as the SOI, then use statistical generated the v o al nuethferoEmlN us iinnog -S ta ocu ti tchaelrnmaOnsrcoisltl at p io rne , v re alra ia ti bolne ships between these forec agement. fic locat siowne . nAele te drn to at p iv reeldyi , ctw , esuccohuaasstraii ndices and the This study demonstrated that the skill obtainable in models to ld us nefatlhleatcaosuppelceid A gr uosu tr nad li s a , th weaisrussueffiinc ie c n ro tptmo an ju asg ti efmy, enot. n Pr eecsounmoam bl iycp en re s d em ic b te lderpurnesdiocftasneaas tm ur o fa scpehetreimc peratures, then use these forecasts could also be useful in drought-dicti sea surface temperature msotdoelpfro ep rc aerdew pr it e h mmiannaatg io enmeonftadpep ci rsoiporniam te aksitnogc , kifnogrirnas te ta sncoen in padse to te ra r l tChoenbsoi ns edse of trsatbrlera ate tihno fa gy ulglhatnadndotthee st rinvga riables of interest. properties (McKeon et al. 1990). prediction. for using models iisnnseeead so endaltoc li s m el aetcet