Influence of large-scale climate indices and regional meteorological elements on drought characteristics in the Luanhe River Basin

Frequent drought disasters have significant impacts on socio-economic and ecosystems, and it is crucial to explore the propagation characteristics of drought for disaster prevention and mitigation. In this paper, based on 0.25(degrees) x 0.25(degrees) grid-point Meteorological hydrological and large-scale climate factor data, the start-to-start, peakto-peak, and end-to-end drought propagation times, and the periods and rates of drought development and recovery were estimated for 11 regions in the Luanhe River Basin under stationary and non-stationary conditions. The Generalized Additive Model for Location, Scale and Shape (GAMLSS) framework was used to construct stationary and non-stationary models to capture the stationary and non-stationary drought characteristics respectively, and then the drought development and recovery patterns, and drought propagation times were assessed. The results showed that under the influence of climate factors, severe drought events occurred in most study areas, the duration of meteorological drought was prolonged by 0.1-0.6 months, and the peak intensity was increased by about 0.05. The severity of hydrological drought increased by 0.2-0.8, and the peak intensity decreased by 0.1-0.2. The rate of development and recovery of hydrological drought was accelerated by 0.1-0.2 per month. The propagation time of start-to-start was shortened by 0.2 months, and the propagation time of endto-end was extended by 1-2 months. These mean that water resource control authorities need to propose responses to droughts more quickly.