A high intensity, short duration, localized rainfall event initiated debris flows in very steep slopes.
Long-term analysis of runoff in semi-arid catchment of Lemon, a study region located in southwest Western Australia (Ruprecht and Schofield 1989), showed that the minimum rainfall to initiate runoff had shifted fundamentally due to land use change.
So, for example, while there was optimism that increasing tree cover in the arid regions of northern China would increase rainfall and initiate wider greening even without explicit attention to long-range water transport (e.g., Jiang and Liang 2013), recent appraisals suggest little progress in the driest areas (Ahrends et al. 2017).
However, under warmer conditions and when there is sufficient turbulence, rainfall can be initiated by a coalescence process that involves condensation nuclei, growth of ice particle by collision with supercooled droplets and melting in the lower zone of the cloud (Rogers and Yau, 1989).
Land use also affects the minimum amount of rainfall required to initiate surface runoff.
For example, limited surface vegetation and the accumulation of regolith on slopes during long dry periods allow a relatively short and weak rainfall event to initiate mass movements in arid areas.
Swine manure slurry inoculated with E. coli and Salmonella, and with added bromide tracer, was applied on the top of the plots and simultaneously initiated the simulated rainfall.
A program of continuously recorded water temperature profiles has shown that salinity stratification initiated by direct rainfall onto the lake's surface and local runoff into the lake results in the onset of heliothermal conditions within hours of rainfall onset.
The availability of extended records of rainfall and other climatic data, which could be used to obtain stream flow data, initiated the practice of rainfall-runoff modelling.
A comparison of the initiation areas of the landslides triggered by rainfall and by the earthquake revealed that the coseismic landslides initiated in the upper parts of hillslopes of rainfall-induced landslide scars in the study area (Figs. 3 and 7).
After a series of debilitating rainfall failures in northern Ethiopia, a microdam construction programme was initiated in the 1990s to harvest rain water.
