Finally, the graphs that show the spatio-temporal variability of rain
with their analysis were made.
The analysis of the events was carried out by grouping
different-duration events and identifying the internal characteristics
of each. This allowed to understand the internal structure of the rain
during events in the city of Manizales. An isolated event of rain was
defined as precipitation with a magnitude and duration potentially
capable of generating surface runoff and an occurrence continuous in
time, without interruptions greater than 15 minutes (interruptions equal
or greater than 15 minutes were considered separate events).
The temporal distribution of the rain events was analyzed considering
only seven (7) of the thirteen (13) climatological stations of the
network because the other stations did not contain information until
2010 (that is, Aranjuez, Emas, La Nubia, Observatory, La Palma, Posgrado
and Yarumos), located at strategic points in the city. The available
records analyzed were from January 2006 to July 2014, to ensure the
homogeneity of the data throughout the study.
Figure 2. (Left ) Events lasting 20 minutes at
the Posgrados station during 2006-2014 (Right )
Dimensionless 20-minute event curves for the Posgrados station during
2006-2014
The estimation of the temporal behavior of each station was made with
the rain data for each duration of the event, from which a dimensionless
graph of rain versus time was obtained for all the events. As an example
of the 68 rain events of 20-minute of duration recorded at the station
of Posgrados (2006-2014), the accumulated precipitation is shown (see
Figure 2, left) and then the same information but dimensionless (see
Figure 2, right), which can allow estimating the mean values and the
90th percentile.
The values of the different percentiles were later obtained as well as
the averages, such as the one obtained for the station of Posgrados
(Figure 3). This same procedure was applied for rains of all durations
for all network stations in Manizales.
Figure 3. Percentiles from 5% to 95% for the Posgrados
station and rain events lasting 20 minutes