Gap Filling and consistency analysis in monthly rainfall series: case study in southeastern Mato Grosso

Abstract

The analysis of precipitation time series is crucial for understanding climate patterns and managing water resources. However, data gaps caused by missing information, technical issues, and data transmission failures compromise the accuracy of climate analyses and forecasts. This study aims to address these gaps and assess the consistency of monthly rainfall series in southeastern Mato Grosso, using the regional weighting method and the double-mass analysis. Data from five rainfall stations were selected: Vale Rico (01654005), Alto Araguaia (01753000), Fazenda Taquari (01853000), Alto Garças (01653004), and Itiquira (01754000), covering the period from 1984 to 2019, were extracted from the Hidroweb platform of the National Water and Sanitation Agency (ANA). The regional weighting method was effective in filling gaps. Consistency checks using the double-mass method revealed a linear trend in data, indicating no inconsistencies in the filled data. Notably, the Fazenda Taquari station (01853000), with had the mostgaps filled, showed a pronounced linear trend, demonstrating the effectiveness of the methodology. The findings suggest that the regional weighting method is suitable approach for gap filling in rainfall series, thereby enhancing the quality of data for hydrological studies in the region.