Abstract:
This paper focuses on the analysis of precipita-
tion patterns, using a Local Area Weather Radar to collect
information about the precipitation distribution in an
Andean region of southern Ecuador (cities of Loja, Zamora
and Catamayo). 54 representative events were selected to
develop daily precipitation maps and to obtain their rele-
vant characteristics, which were related to the topography
and the season. The results showed that a strong correlation
between the areas covered by precipitation (RA coef?cient)
and the season exists. In general, humid air masses come
from the east (Amazon Basin), but during the main rainy
season (December to April), humidity also frequently
enters the study region from the west (Paci?c Ocean). The
rainy season is characterized by convective precipitation,
associated with higher evaporation rates during austral
summer. The relatively dry season is formed between May
and November, but considerable precipitation amounts are
registered, too, due to advective moisture transport from
the Amazon Basin, a result of the predominant tropical
easterlies carrying the humidity up the eastern escarpment
of the Andes, generally following the natural course of the
drainage systems.