A framework for modeling an agronomic system's vulnerability to climate change with reflections from the Caspian coastal agro-ecological zone of Iran.

Assessing the vulnerability of different sectors to climate change has great importance in determining the appropriate adaptation measures to deal with climate change impacts on a river basin scale. In this research, using a framework for modeling the agronomic system vulnerability to climate change, vulnerability assessment under different scenarios was conducted for the Gorganrud River Basin located in the agro-ecological zone of the Caspian coastal plain of Iran. Considering exposure, susceptibility, and lack of resilience components, 12 indicators were chosen and quantified for both agronomic-environmental and socio-economic aspects. The SSM-iCrop2 model was used to simulate crop yield under current and climate change scenarios across the basin. The analysis indicates that in the current condition, the vulnerability level is different across the watersheds of the Gorganrud River Basin. By applying the climate change scenarios, agronomic system vulnerability would increase in the basin to some extent, particularly in Madarsu and Tilabad watersheds attributed with high vulnerability (0.63 and 0.61, respectively). This justifies the need to implement adaptation plans for encountering water shortage in the future. The analysis also suggests that the vulnerability of the agronomic system for adaptation scenarios characterized by less water consumption under climate change conditions is going to be slightly different from the vulnerability under the climate change scenarios. Due to an increase in agronomic system vulnerability under climate change scenarios, coupled with the fact that most watersheds (except Chehelchai, Nardin, and Narmab) are moderately vulnerable even under current conditions, policymakers and planners should promote crop and livelihood diversification programs aiming to prevent an increase in agronomic vulnerability.