**3.1 Study area and data pre-processing**

The study used sounding data from weather station denominated SBBE, number 82193 (Belem airport), in the interval 2003 to 2010. The data were collected at the University of Wyoming website. The Figure 3 shows the station location, in the eastern Amazon Region, with their geographic coordinates (latitude: 1.38 S and longitude: 48.48 W).
