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Yolŋu Aboriginal people’s knowledge about water (“gapu”) and its governance has strong cultural significance and meaning in East Arnhem Land Aboriginal worlds in northern Australia. This study used...

The effects of climate change on groundwater recharge and baseflow in the upper Ssezibwa catchment, Uganda, are investigated. The study first examines historical data, which indeed reveal evidence of climate change based on trends observed in temperature and discharge. For the climate change study, the statistical downscaling model (SDSM) is used to downscale future climate change scenarios, which were obtained from the UK HadCM3 climate model. The downscaled climate is used as input to the WetSpa hydrological model, a physically-distributed rainfall—runoff model, which was used to simulate the resulting hydrological changes. Downscaled climate shows an increase in precipitation in the wet seasons (March—May; October—December) ranging from 30% in the 2020s to over 100% in the 2080s. The corresponding rise in temperature ranges between 1 and 4°C. These changes are shown to give rise to intensification of the hydrological cycle. The mean annual daily baseflow for the current period of 157 mm/year (...

Time series analyses are applied to characterize the transient flow regimes of the Nam La cavern conduit, northwest Vietnam. The conduit transforms the input signal to an output signal, and the degree of transformation provides information on the nature of the flow system. The input for the analysis is net precipitation and the flow hydrograph at the cave entrance, while the output series is the flow hydrograph at the resurgence. Cross-correlation and cross-spectrum analysis are used to investigate the stationarity and linearity of the input-output transformation of the system, resulting in hydrodynamic properties such as system memory, response time, and mean delay between input and output. It is shown that during high flow periods, the flow in the conduit is pressurized. Consequently, the linear input-output assumption holds only for low flows. To highlight the hydrodynamics of the cavern conduit for the high flow periods, wavelet spectrum and wavelet cross-spectrum analyses are applied.