THE NEAR-SURFACE LAYER OF THE OCEAN
Figure 7-19. Contributions of interfacial and bubble mediated components to the total CO 2
air-sea transfer velocity at different wind speeds.
Figure 7-20. Summary of the gas transfer results over the ocean using the dual tracer and
radon techniques as well as direct measurements. The continuous lines are the theoretical
relationships for the gases involved in the corresponding measurement techniques (SF 6 and
3
He, Rn). The theoretical dependence for CO 2 is also shown. The dual tracer data are from
Wanninkhof et al. (1997), Asher and Wanninkhof (1998), and Nichtingale et al. (2000). The
radon data are from Peng et al. (1974), Peng et al. (1979), and Cember (1985). The GasEx-98
data are from Wanninkhof and McGillis (1999), and the GasEx-01 data are from Hare et al.
(2004). To illustrate the effect of surface heat flux and insolation on the air-sea gas exchange
at low wind speed the model curves for all gases are calculated for Q 0 = 130 W m
-2 , Q E = 60
W m
-2 and for two values of I 6 : 0 Wm
-2 and 1000 Wm
-2 (see also Figure 7-17).
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