°°2000~f 1000 

 STANDARD 



500 400 



300 



250 



200 



150 



'dm 



, years 



Fig. 19 Fraction of industrial C0 2 remaining in the lower atmosphere as a 

 function of the deep-ocean-to-surface-layer transfer time, T dm> for several 

 values of the (total) atmosphere to ocean transfer time r 3Sn . The average 

 fraction observed for the lower atmosphere between 1959 to 1969 (42%) is 

 indicated by a horizontal line, and the value of T^ni used as a standard case 

 (1500 years) is indicated by an arrow. 



T 4 



STANDARD 



RELATIVE SIZE OF SURFACE LAYER (N /N > 



mo aO 



Fig. 20 Fraction of industrial C0 2 remaining in lower atmosphere as a 

 function of the relative size of the ocean surface layer, for several values of the 

 atmosphere to ocean transfer time, Tajy,. The average fraction observed from 

 1959 to 1969 (42%) is indicated by a horizontal line, and the value of N mo 

 used as a standard case (2N ao ) is indicated by an arrow. 



estimate of 49% for the entire atmosphere and hence 42% for the lower 

 atmosphere only if the land biota increases in size. 



The use of the transfer function is not intended to achieve precise 

 predictions. Its principal value is to permit a rapid survey of how the attenuation 

 and partitioning predicted by a linear model vary with assumed values of the 

 model parameters. The function also offers a control to check the computational 

 accuracy of time-dependent predictions which involve numerical approxima- 

 tions. In the paper that follows (part II), the time-dependent governing 

 equations of the six-reservoir model will be used in conjunction with the actual 



