Climatological Behavior of Precipitating Clouds in the Northeast Region of Brazil

Rayana Santos Araújo Palharini,Daniel Alejandro Vila

doi:10.1155/2017/5916150

Abstract

This study aims to analyze the climatological classification of precipitating clouds in the Northeast of Brazil using the radar on board the Tropical Rainfall Measuring Mission (TRMM) satellite. Thus, for this research a time series of 15 years of satellite data (period 1998–2012) was analyzed in order to identify what types of clouds produce precipitation estimated by Precipitation Radar (PR) and how often these clouds occur. From the results of this work it was possible to estimate the average relative frequency of each type of cloud present in weather systems that influence the Northeast of Brazil. In general, the stratiform clouds and shallow convective clouds are the most frequent in this region, but the associated rainfall is not as abundant as precipitation caused by deep convective clouds. It is also seen that a strong signal of shallow convective clouds modulates rainfall over the coastal areas of Northeast of Brazil and adjacent ocean. In this scenario, the main objective of this study is to contribute to a better understanding of the patterns of cloud types associated with precipitation and building a climatological analysis from the classification of clouds.

Highlights

The Northeast Region of Brazil (NEB), characterized as a semiarid region, presents scarce rainfall and is frequently affected by long periods of drought [1, 2]
Reference [7] suggests that climate changes and human interference can result in more heavy rainfall events. These significant events can be caused by disturbances in other systems patterns known as the Intertropical Convergence Zone (ITCZ) [8], Upper Tropospheric Cyclonic Vortex (VCAN) [9], disturbances in the trade winds [10], squall lines [11], front systems in southern of NEB [12], and South Atlantic Convergence Zone (SACZ) [13]
In the present investigation a time series of 15 years of Precipitation Radar (PR)/Tropical Rainfall Measuring Mission (TRMM) satellite data was analyzed in order to obtain a better understanding of the cloud types associated with precipitation in Northeast Region of Brazil

Summary

Introduction

The Northeast Region of Brazil (NEB), characterized as a semiarid region, presents scarce rainfall and is frequently affected by long periods of drought [1, 2]. Reference [7] suggests that climate changes and human interference can result in more heavy rainfall events These significant events can be caused by disturbances in other systems patterns known as the Intertropical Convergence Zone (ITCZ) [8], Upper Tropospheric Cyclonic Vortex (VCAN) [9], disturbances in the trade winds [10], squall lines [11], front systems in southern of NEB [12], and South Atlantic Convergence Zone (SACZ) [13]. The subregion further north for example is more common in the presence of ITCZ that is characterized by a band of convective cloud cover that surrounds the equatorial region

Objectives

Results

Conclusion