100 



BKOECKER 



[CHAP. 4 



reservoir (see Figs. 2 to 8). The parameters for models I, II and III have been 

 chosen to approximate the Pacific plus Indian Oceans. Ratios of the fractiona- 

 tion -corrected 14 C concentrations in the dissolved CO2 of each reservoir to that 

 in atmospheric CO 2 given in these figures are based on the data summarized 

 in Tables I, II and III. No data are available for the Indian Ocean. 



For each model the mean residence time of both CO 2 and of dissolved solids 

 has been calculated for each reservoir. The calculations are made for mixed 

 layer depths of 100 m and of 300 m, and for ratios of the ocean-atmosphere 



WORLD-OCEAN MODEL (Cases EZ!C and EZD) 



0.61 A U 



\ 0.I2A.U 



I D.U(C) 

 3 DU.(D) 



35 D.U.(C) 

 33DUID) 



31 P. ♦ I SURFACE * 3)1 



C/C A = 0.965 



-r _ /I6YI 

 T C0 2 " 150YI 



0.I5V.U.IC) Tnc .r50YR(C) 

 0.45V.U (D) ' Ds \|50YR(D) 



PACIFIC y INDIAN 

 DEEP WATER 

 C/C A = 0.800 



6.1 V.U.(C) 

 5.8V.LMD) 



Tco 2 I T D . s .= l050YR 



© ! A SURFACE 



OYR(D) 

 0.06 VUICI t ./IBYRICI 

 0.17V U (D) 'D s "l55YR(D) 



ANTARCTIC 

 OCEAN 

 C/C A 0BS.= 0.885 

 C/C A CAL= 0.910 



T COz =65YR 

 T D .S. = I05YR 



i £ 6 I 1 



J0.04AU 



rcoAr iC 



ATLANTIC 

 D_EEP WATER 

 C/C A = 0.900 



2.0 V.U.(C) 

 1.9 V.U.(D) 



Tco,= T D .s=650YR 



«46 



"ARCTIC" 

 OCEAN 



C/C A 0BS.= 

 0.970 



C/C A CAL.= 

 0.960 



12 V.U 



r C o 2 =35YR 

 r D S=40YR 



£| =I| = E4 = I 4 = E 6 = Z 6 -I0M/M 2 /YR 

 F 3 = I 3 = 50M/M 2 /YR 



I|A l =2.2xl0 15 M/YR 

 I 4 A^0.8t\0 15 M/YR 



I 3 4 3 = 2.3xl0 l5 M/YR 

 J 6 /l 6 = 0.2xlO' 5 M/YR 



R| 3 =R 3 l = I.OxlO 15 M/YR 

 ft 32 = ff 23 =l -9 xlO 15 M/YR 

 *i4--*46 --*65-- R 51 = '-0 xlO'5 M/YR 



Fig. 



7. Cases C and D differ in the thickness assigned to the surface ocean layers. The 

 cases in this figure differ from those in Fig. 6 only in the value assigned to the ratio of 

 Antarctic to non-Antarctic ocean-atmosphere exchange rates. 



exchange rate in the Antarctic to that in the rest of the ocean of 1 and of 5, 

 and for various combinations of modes of interactions between the reservoirs. 

 For the "cyclic Atlantic" (cases A, B, C and D for the world-ocean model) five 

 ocean mixing-rate parameters could be determined. As only three parameters 

 must be fixed, the Arctic and Antarctic reservoir 14 C concentrations have been 

 computed for comparison with the measured values (see Figs. 6 and 7). In the 

 other cases such internal cross-checks are not possible. 



The results of these calculations allow several important observations to be 

 made: 



(1) Regardless of the model selected, steady-state assumptions require that 

 dissolved solids remain in the deep Pacific Ocean more than 1000 years before 

 returning to the mixed layer. The corresponding time for the Atlantic is about 

 two-thirds as great. The exact time is, as pointed out by Craig (1958), strongly 

 dependent on the rate at which 14 C can be supplied to the deep sea through 



