Document Type : Original Article

Authors

• Hadi Ramezani Etedali ¹
• Sakine Koohi ²

¹ IKIU

² Department of Water Engineering, Faculty of Agriculture and Natural Resources, Imam Khomeini International University, Qazvin

Abstract

Abstract: Climate change, particularly through heat stress, presents a significant threat to agricultural production in Qazvin Province, a vital agricultural hub in Iran. This study aims to analyze the temporal patterns of heat stress—encompassing frequency, intensity, and duration—affecting strategic crops such as wheat, maize, and barley, and to evaluate its impact on their yields under the SSP2-4.5 and SSP5-8.5 climate scenarios. To this end, historical data (1997–2014) from the Qazvin synoptic station and projections from five global climate models (CNRM-CM6-1, CanESM5, GFDL-ESM4, HadGEM3-GC31-LL, MIROC6) were employed, utilizing an optimized ensemble model approach. The findings indicate that, particularly under the SSP5-8.5 scenario, the frequency of heat stress will rise substantially, with maize identified as the most vulnerable crop, experiencing nearly 100% heat stress frequency during its growing season by 2099. Furthermore, both the intensity and duration of heat stress are projected to increase, resulting in significant yield reductions: wheat from 4.20 to 3.00 ton/h, barley from 3.80 to 2.18 ton/h, and maize from 37.9 to 33.1 ton/h. These results highlight the urgent need for adaptation strategies in Qazvin Province, such as adjusting planting schedules and developing heat-resistant crop varieties. Additionally, meticulous planning for water resource management and infrastructure development is critical to bolster agricultural resilience, as neglecting these measures could jeopardize regional food security and economic stability.

Keywords

• Heat stress
• Crop yields
• SSP scenarios
• Global climate models

Main Subjects

• Climate change