This study analyzed 10 years of spatial and temporal distribution of lightning and precipitation systems and their characteristics such as reflectivity, brightness temperature and
height of the precipitation systems sampled by the Lightning Imaging Sensor (LIS),
Precipitation Radar (PR) e TRMM Microwave Imager (TMI) sensors onboard of the Tropical
Rainfall Measuring Mission (TRMM) satellite. This dataset is organized and stored by the
research group of tropical convection of the University of Utah from December 1997 to
February 2009. This work also analyzes data from outbreaks of fires detected by INPE in the
period 1998 to 2008. It was selected an area bounded between 60°W to 45°W of longitudes
and between 10°S to 5°N of latitudes, which was subsequently divided into nine sub-areas for
more detailed information. To investigate the possible influence of burning in the number of
lightning flashes, we selected eight areas, in which four present the highest number of fire
outbreaks and four with the lowest ones. The precipitation systems were classified according
to the method of Nesbitt et. al (2000), and obeying the new definition of the data proposed by
Liu (2007). The precipitation features used in this work are named ALLPFS, which are all
systems with rainfall pixels estimated by the 2A25 algorithm. These systems have the
categories of PFS (present information of brightness temperature) and OTHPFS (without
information of brightness temperature). Within the PFS, the systems are defined as those
without ice signature (NOICE), with ice signature (WICE) and mesoscale convective systems
(MCS). The most intense MCSs are defined as IMCS. The results show that the southern
regions of Pará, around Belém and Marajo Island were the ones with the highest occurrence
of lightning in the Amazon region, with values exceeding 20 to 35 lightning flashes/ km²/year.
The NOICE systems were equally frequent in all regions. The categories WICE and MCS are
those which contribute most to the production of lightning over these regions. It was also
observed that the electrified systems have great contribution to the estimated amount of
rainfall over central and southern parts, with percentages above 50% in the area SOUTH. The
monthly variation of the lightning occurrence densities in the studied area showed that the
highest occurrence of lightning was found over the city of Belem during the months from
January to June, peaking in January. The highest occurrences in the southern sector of eastern
Amazonia were concentrated in the months of September to December. In the analysis on the
interaction between lightning and burning spot areas, it was not possible to verify a consistent
correlation between lightning and fires, showing that despite the large number of fires
observed on these areas, other factors influence the production of lightning flashes.
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