THE CLIMATE OF LOURENCO MAROUES. 3II 



velocity of the other prevaihng winds, accounts for such a con- 

 dition being more pronounced in the months from April to 

 August. At I.ourenco Marques the average velocity of the wind 

 is highest from September to January. 



Tables VII, \'III and IX, showing the frequency and the 

 number of kilometres traversed in the dilferent courses, facilitate 

 considerably the analysis of the conditions in tlie various months. 



In the hottest season, from October to l\Iay, liNE and SSW 

 winds prevail, willi a small percentage of winds from the NW 

 ([uadrant and from SW to W directions. The prevailing wind 

 from the SW quadrant successively veers to SW from October 

 to May, and an increase in the percentage from NE to ENE is 

 similarly noticed up to February, when the latter direction pre- 

 vails, decreasing, however, considerably in March. Thus, the 

 prevailing winds during the hottest months are the sea winds 

 and also the SSW wind, which is rather cold. In the remain- 

 ing months, when the land and sea breezes are more pronounced, 

 the W winds are naturally more freqtient. The frequency of 

 the XX\A' wind increases from April to June, and decreases in 

 the three following months. Up to Jtme the wand increases 

 in fref[uency from SE to SW, and it again blows with more 

 frequency from S, SSE and from the NE quadrant. 



In short, the winds from the W ([uadrant, principally NNW 

 and next SSW, prevail in ^lay, lune, and July ; in November, 

 December, and lanuary tlie winds from NE and SE quadrants 

 prevail, especially ENE, E, ESE. and also S. 



The other months may be regarded as a transition between 

 these more clearly defined conditions. 



The percentage of the number of kilometres traversed in 

 the different directions accompanies the percentage of frequency, 

 the former showing an increase in the directions in which, as we 

 have seen, the wind blows more violently. 



The Monsoons at the N of the Mozambic[ue Channel are not 

 felt here, although they may also have some influence on the 

 velocity and direction of the wind. 



A study of Table No. X shows the influence of the SE 

 trade wind which, as is known, prevails in the Indian Ocean in 

 this latitude, as the annual resultant is always aj)proximately SI^. 

 and in most months, especially in the hot months, the resultant 

 also falls to the same quadrant. These figures show a great dis- 

 placement of air toward XW, which is no doubt due to the great 

 aspirator of E(juatorial Africa, as Commander Hugo de Lacerda 

 had already concluded in 1909, thus justifying the greater 

 frequency of depressions in the hot season through this aspiration 

 being more pronounced. Commander Hugode Lacerda put 

 forward the hypothesis that the high pressure systems of the 

 two Oceans that wash the coast of Africa might compensate for 

 the loss of balance which shows a tendency to occur in Central 

 Africa, and strengthened his opinion by the circumstance of there 

 being no resultant at Kimberlev. 



