Complex sentence: The main features of the climate are high temperatures and abundant rainfall throughout the year; this abundant rainfall makes water scarcity and extended periods of drought uncommon; much of the region has a positive water balance.
Split into simpler sentences: The main features of the climate are high temperatures and abundant rainfall throughout the year. With abundant precipitation throughout the year, water deficiencies and extended periods of drought are uncommon, and much of the region has a positive water balance.