Performance of meteorological data for drought monitoring in areas of the Brazilian Semi-Arid

Author(s)

Jose, Rafael Vinicius de Sao ; Martins, Leticia Lopes ; Coltri, Priscila Pereira ; Steinke, Ercilia Torres ; Greco, Roberto

• Document type: Journal article
• Source: THEORETICAL AND APPLIED CLIMATOLOGY; v. 156, n. 4, p. 15-pg., 2025-04-01.

Abstract

Hydrometeorological monitoring is often constrained in regions with sparse station networks, such as the semiarid areas of developing or least developed countries. This study aimed to evaluate the performance of precipitation data from two global databases, NASA POWER and ERA-5, from 1985 to 2020, and to characterize meteorological droughts in Cura & ccedil;& aacute; and Juazeiro, two municipalities in Bahia, northeastern Brazil. The performance of these databases was assessed using the Pearson correlation coefficient (R2) and the modified Willmott index of agreement, with NASA POWER demonstrating stronger agreement with ground station data when compared to ERA 5. Therefore, the Standardized Precipitation Index (SPI) was applied using the data from NASA POWER, the better-performing dataset. The results showed that mild to moderate droughts were more frequent in Cura & ccedil;& aacute; and Juazeiro, whereas severe and extreme droughts, though less common, tended to last longer. This study highlights the reliability of satellite-based data, such as NASA POWER, as a valuable alternative for drought monitoring in Brazil's semiarid region, where meteorological station density is low. The findings underscore the importance of integrating alternative data sources with field stations and emphasize the need for further research to validate these tools for climate risk analysis, drought monitoring, and proactive management in susceptible regions. (AU)

• FAPESP's process: 20/09838-0 - BI0S - Brazilian Institute of Data Science
• Grantee: João Marcos Travassos Romano
• Support Opportunities: Research Grants - Research Centers in Engineering Program