Evaluating the Latest IMERG Products in a Subtropical Climate: The Case of Paraná State, Brazil

Jéssica G Nascimento,Helizani C Bazame,Anderson L Ruhoff,Christopher M U Neale,Ivo Z Gonçalves,Daniel Althoff,Sergio N Duarte

doi:10.3390/rs13050906

Abstract

The lack of measurement of precipitation in large areas using fine-resolution data is a limitation in water management, particularly in developing countries. However, Version 6 of the Integrated Multi-satellitE Retrievals for GPM (IMERG) has provided a new source of precipitation information with high spatial and temporal resolution. In this study, the performance of the GPM products (Final run) in the state of Paraná, located in the southern region of Brazil, from June 2000 to December 2018 was evaluated. The daily and monthly products of IMERG were compared to the gauge data spatially distributed across the study area. Quantitative and qualitative metrics were used to analyze the performance of IMERG products to detect precipitation events and anomalies. In general, the products performed positively in the estimation of monthly rainfall events, both in volume and spatial distribution, and demonstrated limited performance for daily events and anomalies, mainly in mountainous regions (coast and southwest). This may be related to the orographic rainfall in these regions, associating the intensity of the rain, and the topography. IMERG products can be considered as a source of precipitation data, especially on a monthly scale. Product calibrations are suggested for use on a daily scale and for time-series analysis.

Highlights

Precipitation plays a fundamental role in the hydrological cycle
The rainfall distribution density curve, which relates the precipitated volume to the distribution of observed and estimated precipitation were consistent over all months of the year
The performance of Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (GPM) (IMERG) version 6 products in estimating daily and monthly precipitation were evaluated in comparison with the data observed by 511 gauges distributed in the state of Paraná in Brazil

Summary

Introduction

Precipitation plays a fundamental role in the hydrological cycle. It is considered the main water source input in the soil water balance and runoff and is used as an input in hydrological and climatological modeling. In the management of water resources, knowledge of the volume and intensity of precipitation is essential for the prediction of floods and droughts, the distribution of water for urban and industrial uses, and the planning of irrigation in agriculture and hydraulic infrastructure. Precipitation can be measured by gauges, sensors onboard satellites, and radars [1,2,3]. Precipitation gauges are fundamental instruments, and their observations are considered as a reference in many studies [4]. In South American countries, monitoring by gauges is limited in terms of infrastructure, maintenance, density, and frequency of observations [6,7]

Objectives

Methods

Results

Discussion

Conclusion