The dynamic identification mechanism research of drought based on process description

Abstract

Drought is one of the most common natural disasters, which can cause heavy losses on a global scale. Strengthening the research on drought identification mechanism has an important guiding role in drought disaster prevention and mitigation. The current drought identification is mostly static in the process of drought, and there is a problem that the historical evaluation information and the drought prediction information are not closely combined, with limited application value. Based on the physical cumulative and recessional effects of drought events, this paper further uses the Standardized Precipitation Index (SPI) to divide the whole drought process into four stages: accumulation → outbreak → reaction → restoration. In addition, this study proposes a new dynamic identification mechanism based on drought process, and develops a drought prediction model combining singular spectrum analysis and BP neural network (SSA-BPNN), filling the gap between scientific research and practical application. Using three drought events in the Yulin region of China as examples for simulation studies, the results show that the use of the new mechanism can not only improve the application value of the SSA-BPNN model, but also effectively advance the drought preparation time and resistance level. HIGHLIGHTS The described drought events process is based on Hurst phenomenon.; SPI was used to divide the stages of drought process.; A dynamic identification mechanism of drought events was constructed.; Case simulation was carried out to verify the drought events dynamic identification mechanism.;

Keywords

• case simulation
• division of drought stages
• drought process description
• dynamic identification mechanism