166 



MALKUS 



[chap. 4 



Fig. 32 shows the result under the assumption that the August Rs distribu- 

 tion is generally valid for the summer hemisphere and the February distribution 

 for the winter hemisphere. Heat fluxes from summer to winter pole are pre- 

 sented in multiples of lO^^ cal/sec, the basic "unit" used in the equatorial 

 study. The zero line is crossed near latitude 12° in the summer hemisphere, 

 which corresponds well to the mean equatorial trough position in July- 

 September. Maximum transport is 0.49 units to the summer pole and 1.06 units 



90 



60 

 50 



40 



30 



20 

 10 



(U 

 XI 



^ 



To Summer Pole 

 __J I \ I L 



1.0 0.8 0.6 0.4 0.2 

 lO'^ col/ sec 



0.6 0.8 1.0 1.2 



10- 

 20- 

 30 



40 



50- 

 60- 



90 



Fig. 32. Latitudinal heat fluxes computed from integrating London's (1957) Northern 

 Hemisphere Rg figures for no-storage months of February and August. February 

 fluxes assumed applicable to winter hemisphere, August fluxes to summer hemisphere. 

 (After Riehl and Malkus, 1958, Fig. 3.) Ordinate in degrees latitude; abscissa in lO^^ 

 cal/sec around whole latitude belt. 



to the winter pole, a difference of 0.57 units. In the equatorial zone, Rs is about 

 0.31 units in belts 10°-latitude wide in both seasons. Since the trough shifts 

 seasonally by 17° latitude in the mean, an area yielding Rs = (17/10) x 0.31 = 0.55 

 units is transferred from the summer to the winter side of the trough during its 

 seasonal migration. That amount is practically identical with the difference of 

 heat transport to summer and winter poles ! This calculation suggests that no 

 heat flow takes place through the equatorial trough, at least at the seasonal 



