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ATavernier 



■ Key West 



• Royal Palm 

 Ranger Station 



i l l I I I I I I I I I 



Jan Feb Mar Apr May June July Aug Sep Oct Nov Dec 



Figure 10. Average monthly rainfall for three representative stations in 

 the study area (adapted from USDC 1981a, 1981b, 1981c). 



Thomas' (1970, 1974) analysis 

 of the average annual rainfall 

 distribution for the Everglades/Bay/ 

 Keys basin is presented in Figure 

 11a. Annual (and monthly) rainfall 

 varies considerably from year to 

 year; ranges in excess of 102 cm 

 (40 in) for an individual station 

 are commonplace. For example. Key 

 West reported 160 cm (62.92 in) 

 during 1969 and 51 cm (19.99 in) in 

 1974 (USDC 1981b). Figures lib and 

 11c illustrate the mean total wet 

 season and dry season rainfall. 



respectively, for the study area. 

 These two figures highlight the dif- 

 ferences between the mainland and 

 the keys' annual rainfalls. 



A precipitation characteristic 

 commonly reported and of interest 

 for air pollution and ecological 

 work is the number of days on which 

 certain size classes of rainfall oc- 

 cur, i.e., rainfall greater than or 

 equal to .254 cm (0.10 in). Table 4 

 presents a summary of mean number 

 of days per month with rainfall 



28 



