Streams may receive water from different sources in their catchment. There is limited understanding of which water stores intermittent streams are connected to. Using geochemistry we show that the intermittent streams in southeast Australia are connected to younger smaller near-river water stores rather than regional groundwater. This makes these streams more vulnerable to the impacts of climate change and requires management of the riparian zone for their protection.

GRACE/GRACE-FO provided global observations of water storage change since 2002. Scaling is a common approach to compensate for the spatial filtering inherent to the results. However, for complex hydrological basins, the compatibility of scaling with the characteristics of regional hydrology has been rarely assessed. We assess traditional scaling approaches and a new scaling approach for the Indus Basin. Our results will help users with regional focus understand implications of scaling choices.

A novel approach for evaluating individual and combined impacts of drought and salinity in real-life settings is proposed using Sentinel-2. We found that crop responses to drought and salinity differ between growth stages. Compared to salinity, crop growth is most strongly affected by drought stress and is, in general, further exacerbated when co-occurring with salinity stress. Our approach facilitates a way to monitor crop health under multiple stresses with potential large-scale applications.

Our study uses a statistical boosting model for estimating low flows on a monthly basis, which can be applied to estimate low flows at sites without measurements. We use an extensive dataset of 260 stream gauges in Austria for model development. As we are specifically interested in low-flow events, our method gives specific weight to such events. We found that our method can considerably improve the predictions of low-flow events and yields accurate estimates of the seasonal low-flow variation.

Most catchments plot close to the empirical Budyko curve, which allows for the estimation of the long-term mean annual evaporation and runoff. The Budyko curve can be defined as a function of a wetness index or a dryness index. We found that differences can occur and that there is an uncertainty due to the different formulations.

Our study quantified the altitudinal precipitation gradients (PGs) over the Third Pole (TP). Most sub-basins in the TP have positive PGs, and negative PGs are found in the Himalayas, the Hengduan Mountains and the western Kunlun. PGs are positively correlated with wind speed but negatively correlated with relative humidity. In addition, PGs tend to be positive at smaller spatial scales compared to those at larger scales. The findings can assist precipitation interpolation in the data-sparse TP.