Abstract:

To address the challenges posed by low temperature and continuous rainy weather disasters affecting flue−cured tobacco production in Hubei province, this study established a dynamic monitoring index system for such disasters across the root extension stage, vigorous growth stage and maturation stage of flue−cured tobacco. The system was developed using historical disaster and meteorological observations data from 1961 to 2020, high−resolution grid−based analysis data from 2013 to 2022, and climate projection data from the BCC−CSM model for the period 2023−2052. A risk assessment model for low temperature and continuous rainy weather disasters in Hubei’s flue−cured tobacco was constructed based on three dimensions: the hazard of disaster−inducing factors, the sensitivity of the disaster−prone environment and the vulnerability of the exposed body. The risks under future climate scenarios were evaluated by integrating the low−forcing SSP1−2.6 and medium−forcing SSP2−4.5 emission scenarios. The results indicated that: (1) the dynamic monitoring index system for low temperature and continuous rainy weather disasters in Hubei’s flue−cured tobacco included daily average temperature, sunshine hours, precipitation and the duration of the weather process. Threshold values for key indicators were defined based on the climatic resources requirements during different growth stages. For example, during the root extension stage, a precipitation event lasting≥4d (allowing 1d without precipitation) or ≥7d (allowing 2 non−adjacent days without precipitation), with a daily average temperature ≤17℃, sunshine hours ≤3h and average precipitation ≥4mm per event, were identified as the critical thresholds for a disaster event. (2) From 2013 to 2022, the spatial distribution of disaster risk showed higher levels in western and southern Hubei and lower levels in the east and north. The middle risk area accounted for 49.91%, primarily concentrated in the tobacco−growing regions of Shiyan, Shennongjia and Enshi. Lower risk areas (40.48%) were mainly located in the eastern parts of Xiangyang and Yichang, as well as Yunyang and Danjiangkou in Shiyan. Higher risk areas (9.07%) were concentrated in southwestern Hubei, with no areas classified as highest risk. (3) Under the SSP1−2.6 scenario, the higher risk area for low temperature and continuous rainy weather disasters in Hubei’s flue−cured tobacco exhibited a trend of initial increase followed by a decline from 2023 to 2052. During period I (2023−2032), the area increased by 14.60% compared to the baseline period (2013−2022), while during period Ⅲ (2043−2052), it decreased by 12.84% compared to period II (2033−2042). Under the SSP2−4.5 scenario, the change in risk zone region was relatively stable and the middle risk region showed a fluctuating pattern of decrease−increase−decrease. The areas around Shennongjia in western Hubei and the southwestern region remained consistently at the highest risk and higher risk zones for low temperature and continuous rainy weather disasters. These findings provide a scientific basis for optimizing planting layouts and implementing phased disaster prevention and mitigation strategies in tobacco−growing areas of Hubei. To cope with future climate change risks, it is recommended to enhance resilience by improving monitoring and early warning systems, adjusting planting structures, promoting stress−resistant varieties, and strengthening agricultural insurance mechanisms.

Key words: Flue?cured tobacco in Hubei, Low temperature and continuous rainy, Monitoring criteria, Disaster risk, Emission scenario