SECKEL and YONG: SEA-SURFACE TEMPERATURES AND SALINITIES 



I50| | | | | | | | | I I I I I I I I I I I M I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 



1 I i ! i r 



u 



• 0.30 

 UJ 



E 



I 020 

 □ 



E 



LU 



10 



.ll.hlil.ii 



KOKO HEAD , OAHU 



■IHilLillli.l-ihiiL-liiiliiillil 



illl 1 _ l . l l««Hl.llH.««.. 



i , 



10 



15 



20 



25 



30 



35 



40 



45 



50 



55 



60 



65 



70 



75 



80 



10, ! | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 



008 



J' 0.06 



i i i i i i i i i i i i i i r 



KOKO HEAD, OAHU 



i ° 



04 



0.02 



■IIImM 



■■iili.ill.HilliiLliiillllih-i iLi.ii.iiin.i.-i- 



I 



10 



15 



20 



25 



30 



35 



40 



45 



50 



55 



60 



65 



70 



75 



80 



id cbc*i^K>cc>o' s "^"-"C7icb»bif>croojed — oo^OT(TiQO©QdKf^^Ku>^^U)U>o^u^ioo^ir>^^^^^^^^^^^fOiofOiOfOfOroi<iK>fOioroiOfOiOfOi<ifO 

 — OKtfi^-fOioCMCsjcg 



CM- 

 PERIOD IN MONTHS 



1.00 



oooo 



?ogo 

 CVJ CO 10 

 CSJ — 



qoflONOcoo 



(O — oo — mcoo<T<J>fl-ou>cMcn<oioqf-iO'0 — o>t^inioc<jocr>t^ioioi<icM — ocncor-ioin<r<rioc\j ocricncocqf^ioioininwrotocjtvjcvj-  — oq 



cbi^<Dir>^'fOoJcu — oopo>cricdcocbco>-^f^f^^u3co^u>u5ici^iniriiri 



PERIOD IN MONTHS 



FIGURE 4.— Absolute magnitude of amplitudes of the long-term harmonic functions for Koko Head temperatures, 1956-73; Koko 



Head salinities, 1956-73; and Christmas Island temperatures, 1954-73. 



Koko Head series, these periods are given by 

 n = 18, 36, 54, and 72; and for the 20-yr Christmas 

 Island series, they are given by n = 20, 40, 60, 

 and 80. The mean annual variations evaluated 

 from Equation (2) are shown in Figure 5 panels 

 A, B, and C. 



The mean annual temperature range of 3°C at 

 Koko Head is about twice the long-term range. 

 In contrast, the mean annual salinity range is 

 0.2%o and only about 307c of the long-term range. 

 At Christmas Island the mean annual tempera- 

 ture range is 1°C and only one-quarter of the 

 long-term range. 



At Koko Head the annual sinusoid, although 

 visibly modified, dominates the mean annual 

 changes. In both the temperature and the salinity, 

 the amplitude of the annual sinusoid is an order 

 of magnitude larger than that of the 6-, 4-, and 

 3-mo sinusoids (Figure 4). In the case of the tem- 

 perature, the interference pattern of the 6- and 

 4-mo sinusoids is such that during the first half 

 of the year the annual sinusoid is not visibly 

 affected. Constructive interference by these sinus- 

 oids depresses the annual sinusoid by about 0.2°C 

 in August, which causes first an increase by that 

 amount in October and then a decrease by the end 



773 



