The response time of hydrological components is an important feature for establishing the connections within a hydrological system and for characterizing it. This study proposes a quantitative and qualitative assessment on the response times of river discharge components, especially the baseflow, regarding the impulse provided by precipitation, using time series analyses of time and frequency domains. To this end, a set of complementary methods including correlation and spectral approaches was used, which are: autocorrelation, cross correlation, continuous wavelet transform, and cross wavelet transform. Such framework was applied in multiple and nested basin scales (53, 1,867, and 3,519 km2), located in the Jacaré‐Guaçu River Basin (Southeastern Brazil). Based on a digital filtering technique, it was found the baseflow contributes more than 80% of the annual streamflow, revealing a major role of the aquifer in regulating the river discharge in all three studied basins. In addition, we found baseflow represents a range of 24%–27% of the annual precipitation. The uniform results are mainly due to the similar physical characteristics found in those areas. Overall, our framework indicates a baseflow response time for a precipitation of approximately two years for the smaller basins and three years for the biggest one. Such results can support the water allocation in conjunctive water management, by providing estimates of future surface water availability.

Landslide databases are a potential tool for the analysis of landslide susceptibility, hazard, and risk. Additionally, the spatio-temporal distribution of landslides and their correlation with their triggering factors are inputs that facilitate the evaluation of landslide prediction models and the determination of thresholds necessary for early warning systems (EWS). This study presents an analysis of four widely known global databases—the International Disaster database (EM-DAT), the Disaster Inventory System (DesInventar), the Global Landslide Catalog (GLC), and the Global Fatal Landslide database (GFLD)—which contain relevant landslide information for different regions of the world. These databases were analysed and compared by means of the spatio-temporal distributions of their records. Subsequently, these databases were merged and depurated to obtain a more robust database, namely the Unified Global Landslide Database (UGLD), with 161 countries, 37,946 landslides, and 185,753 fatalities registered between 1903 and 2020. The merging process among the databases resulted in a small number of repeated landslides, indicating that the databases collect very different landslide information and complement each other. Finally, an update of the spatial and temporal analysis of landslides in the world was performed with the new database, in which patterns, trends, and the main triggers were presented and analysed. The results obtained from the analysis of the UGLD database show the American and Asian continents as the continents with the highest number of landslides and associated fatalities, showing a bimodal and unimodal annual temporal pattern, respectively. Regarding the most frequent triggers of landslides, rainfall, anthropogenic intervention, and earthquakes stand out.

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Water managers and stakeholders usually face uncertainty in water availability due to the challenge of incorporating the dynamic nature of precipitation into the water management system. Surface water rights are commonly related to the baseflow component, which is part of the precipitation incident on a watershed. This study proposes an empirical linear model to predict baseflow in perennial streams based on a moving average of antecedent rainfall data and the basin time response. The short-term responses of three nested basins were estimated using cross Fourier spectral analysis, and the proposed model was applied to two nested basin scales (1,867 and 3,519 km 2 ), located in southeastern Brazil. Results indicate that the aquifer stores the rainfall water with regulation times of approximately 60 days for the fast-subsurface flow and approximately 2-3 years for the slow groundwater flow in both basins. Differences between our model results and monthly 95% exceedance discharge (Q 95 ) were as high as 10 m 3 s −1 between September and November in the largest basin, revealing how conservative Q 95 can be as a criterion for water allocation purposes.Despite the simplicity, our empirical rainfall-based model is structurally consistent and robust in representing the hydrological processes involving precipitation, groundwater storage and baseflow interactions at multiple scales by using few inputs and calibration parameters. Because it considers a range of rainfall periods, from past to present, our model contributes to a dynamic, predictive, and integrated water rights management. K E Y W O R D Sbaseflow coefficient, spectral analysis, response time, time series analysis

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