Paper 6 



sites that reflect the interannual changes discussed in this 

 paper. Due to the large month to month variations in pressure 

 and rainlallr a higher degree of smoothing was applied to their 

 anomalies in this illustration. 



The 

 con j 

 peak 

 only 

 t nat 

 i n 



El N 

 i ndi 

 year 

 sout 

 Case 

 oc cu 

 re I a 



E I N 



un ct 



s in 



on 



i t 

 Fi gs 

 i nos 

 ce s 



s 

 he as 

 s wh 

 r red 

 X a t i 



i no (t 

 i on M 

 the a 

 the 

 occu ri 

 . 8.1a 

 ] oc cu 

 c o n t in 

 as to 

 t t ra 

 ere th 

 too 

 on per 



N) 



ith 



noma 



dea 

 . T 

 an 

 r r ed 

 ued 

 rein 

 de 

 e in 



ear 

 i orir 



type 



the 

 lies, 

 ree o 

 he St r 

 d 8.1 



when 

 to fal 

 force 

 system 

 t e rann 

 ly or 



resuL 



act 1 vi t 

 re I axat 

 The in 

 f relax 

 onge r c 

 b for 

 the i nt 

 I rapid 

 the rec 



(Sout 

 ua I re 



too I 

 ted in 



y s 

 i on 



tens 

 at io 

 ases 

 st ro 

 e ran 

 ly t 

 u lar 

 hern 

 la xa 

 ate 

 weak 



et s i 

 t rough 

 i t y of 

 n but 



Cdeno 

 ng and 

 nua I r 

 hrough 



seaso 

 Hemi 

 t ion 

 to fol 

 er Fl 



n pr 1 

 s foil 



such 

 also o 

 ted by 



moder 

 e I axat 



the e 

 na I r 

 sphere 

 was t 

 low th 

 Nino e 



or t 

 owi ng 

 event 

 n t he 

 EN (S 

 ate^ 

 ion w 

 ar ly 

 e I axa 

 sum 

 oo s 

 rough 

 vents 



o and /o 



ant i-E I 



s depend 



time of 



) and 



respect i 



as large 



mont hs o 



t ion of 



mer sea 



ma I I r o 



the sea 



r in 

 Nino 



s not 

 year 



EN(M) 



vely r 

 and 



f the 

 the 



son ) . 



r it 



sona I 



The studies of Berlage (1957^ 1966) and 

 that the S.O. affected not only the 

 hinh but also the North Pacific subtrop 

 relationship .<as explored superficially 

 however^ in that case the Easter Island 

 the former Ship U location component us 

 filter. Here we consider Rape/' Austral 

 the old Ship N position/ because i 

 longitude/ ana use the smoother triple 

 on the index anomalies. A maximum cor 

 was obtained in this case. (This 

 confidence level.) Fiaure fc.3 compare 

 the Ship N-Darwin index. (The plots a 

 From visual inspection one can see 

 ledd-Lag relationship between the two i 

 the change in trend will show up firs 

 in another it will show up first 

 nevertheless/ it is evident that the t 

 being similarly affected by the S.O. I 

 from the Ship N-Darwin index will also 

 outlooks on Fl Nino ana eouatorial Paci 



Troup (1965) indicated 



South Pacific subtropical 

 ical high region. This 



in Quinn and Zopf (1975); 



component was compared to 

 ing the 12-mo running mean 



Islands/ in relation to 

 t is much nearer the same 

 6-mo running mean filter 

 relation of 0.59 at no lag 



is well within the 1% 

 s the Rapa-Darwin index to 

 re correlated at 0.80.) 

 there is no consistent 

 ndex trends; in one case 

 t south of the equator and 



north of the equator; 

 wo high pressure areas are 

 n the future/ indications 

 be actively considered for 

 fie activity. 



USF OF SEA SURFACE TEMPERATURE TRENDS 



A close relationship of fluctuations in north equatorial 

 coun t ercu r rent transport and resulting sea surface temperature 

 (SST) anomalies off the coast of Central America (illustrated in 

 fig. 2 of ks'yrtki 1973) to the interannual variations in southeast 

 trade strength (as reflected in the 12-mo running mean trend of 

 the S.O. index)/ was noted in Quinn (197A). In a recent climato- 



94 



