Evaluation of regional drought risk based on fuzzy risk matrix and connection number

Accurate and effective evaluation of drought risk plays an important role in improving regional drought resistance capacity and reducing disaster risk. Based on the uncertainty characteristics of drought risk system and the chain transfer mechanism of drought risk, a regional drought risk evaluation method based on fuzzy risk matrix and connection number was proposed by introducing connection number to synthesize pessimistic matrix and optimistic matrix in fuzzy risk matrix and calculate risk grade value. The results of risk evaluation in 1999—2005 showed that the comprehensive risk level of drought in Jinan City improved from more than level 3 in 1999 to close to level 1 in 2005, and fluctuated slightly from 2001 to 2002, and the overall risk of drought tended to decrease. The evaluation method considers the interaction between subsystems, and synthesizes grades according to the change characteristics of sample indexes, so as to reflect the dynamic changes of drought risk state in each year. Compared with the traditional risk evaluation methods, the new method can distinguish the drought risk evaluation level of each sub-system and provides a new way for regional drought risk evaluation.