THE CLIiMATK OF LOURENCO MARQUES. 7,21 



When trying- to comprise the characteristics of the chniate 

 for a given region, in one designation only, we may adopt various 

 classilications, grouping two or more of its principal meteoro- 

 logical elements ; and as these have already been defined in regard 

 to Louren(;o Marques, I shall review the classification that can 

 be adopted, taking into consideration the basis in general use. 



The first and oldest classification is the *' Solar " or " Astro- 

 nomical " in three zones — tropical, temperate, and arctic. 



Lourenco Marques is outside the tropical zone proper. 

 Supan, however, whose classification is generally accepted, limits 

 these zones, not by the parallels of latitude, but by the isotherms, 

 and confines the troi)ical zone l)y the isotherm of 20° C (68° F ) 

 which the limit of the trade 7i'iiids and oi the palms approximately 

 coincides with. 



According to this classification. Lourenco Ahirqu(.\s is in the 

 tropical zone, but if we consider its principal Aleteorological 

 elements, comparing them with those characteristic of the tropical 

 and temperate zones (temperature, pressure, respective variation, 

 humidity, rainy season, ([uantity of rainfall, etc., etc.) one can 

 easily see that tliese elements are more or less influenced by the 

 two princi})al zones. That is why I prefer the classification of 

 Koppen, who. paying attention to the relations of temperature 

 with organic life, especially takes into account the number of 

 months of the }ear in which the temperature is kept within cer- 

 tain limits. 



In this classification the term sub-tropical is applied to such 

 regions where from 4 to 1 1 months are hot ( over 20° C or 

 68°" F), I to 8 months are temperate (10" to 20° C or 50° to 

 68° F, and where the rainfall is generally deficient. 



Lourenco IMarques is correctly included in this zone, its 

 average monthly temperature during nine months being over 

 '20° C {p'i^° F), the remaining three months being lower but over 

 10° C (50° F), and its total rainfall being 677'"'" (26.660") 

 { moderate rain) . 



Another general basis for the classification of climates is the 

 geographical one, which comprises three divisions, namely, conti- 

 nental, oceanic, and insular, or littoral ; the latter, which corres- 

 ponds to LoureuQo Marques, more or less, partakes of the 

 defined characteristics of the other zones. 



From the Acro-physical point of view climate has been classi-* 

 fied as folloM's : — As regards temperature — hot, intermediate, and 

 cold, or regular, medium, and extreme ; and as regards humidity — 

 damp, intermediate, and dry. As regards the temperature of 

 Lourenco Marques in addition to what has already been men- 

 tioned, we may classify its climate as regular, as this is the 

 classification applying to those climates where the variation in the 

 amiual temperature is under 10° C (18° F), and here the dif- 

 ference between the hottest and coldest months does not reach 

 8° C (14.4° F). 



