اثر تغییر اقلیم بر نرخ بیمه محصول گندم آبی در پهنه گرم و خشک ایران

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه اقتصاد کشاورزی، دانشکده کشاورزی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران.

10.22059/ijaedr.2025.389930.669356

چکیده

بر اساس پیش‌بینی‌های IPCC، آسیب‌پذیری کشورهای درحال‌توسعه و مناطق گرم و خشک در اثر تغییر اقلیم نسبت به کشورهای توسعه‌یافته و سایر مناطق بیشتر است. اگرچه تغییرات اقلیمی چندان قابل کنترل نیست ولی با تطبیق الگوی کشت با تغییرات اقلیمی بروز خسارات حاصل از آن قابل مدیریت است. یکی از ابزارهای سیاستی مؤثر تغییر در الگوی کشت، بیمه محصولات کشاورزی است. از این‌رو، در این مطالعه چگونگی تأثیر تغییرات اقلیمی بر عملکرد گندم آبی در پهنه گرم و خشک ایران و میزان اثرگذاری آن بر نرخ بیمه عادلانه بررسی شده است. در این راستا، از اطلاعات سری زمانی عملکرد گندم آبی و اطلاعات اقلیمی ایستگاه‌های هواشناسی کشور طی سال‌های 97-1370 برای تعیین توابع توزیع احتمال شرطی عملکرد گندم با استفاده از الگوهای اقتصادسنجی مبتنی بر گشتاور و همچنین تعیین تابع توزیع احتمال ترکیبی استفاده شده است. در آخر، با استفاده از روش شبیه‌سازی، تأثیر تغییرات اقلیمی مورد انتظار در سال‌های آینده بر میانگین و واریانس توزیع ترکیبی عملکرد و همچنین نرخ بیمه عملکرد گندم آبی در پهنه گرم و خشک بررسی شده است. نرخ بیمه واقعی گندم آبی در پهنه گرم و خشک اجرا شده در صندوق بیمه کشاورزی برای سطح پوشش ۷۵٪ معادل 18/5 % است، درحالی‌که نتایج شبیه‌سازی نشان می‌دهد که نرخ بیمه منصفانه برای این محصول در حالت پایه برابر 27/11 % و در سناریوی اجرای هم‌زمان سناریوهای اقلیمی مورد انتظار طی دهه 2030 میلادی معادل 14 % محاسبه شده است. بنابراین، برقراری حق بیمه منصفانه که براساس شرایط ریسکی پهنه اقلیمی محاسبه گردیده باشد، می‌تواند به‌عنوان یک سیاست مناسب برای تسهیل در اصلاح الگوی کشت منطبق با تغییرات اقلیمی در نظر گرفته شود و توصیه می‌گردد.

کلیدواژه‌ها


Extended Abstract

Objectives

The increasing impact of climate change on agricultural production has raised concerns about its consequences for food security and agricultural economies. Among the most affected regions are warm and dry areas, where climatic fluctuations significantly influence crop yields. Iran, as a developing country with warm and dry regions, is highly vulnerable to climate change, particularly in its wheat production sector. Given the strategic importance of wheat as a staple crop, understanding how climate parameters affect its yield and how these changes influence crop insurance premium rates is crucial for sustainable agricultural planning. This study aims to analyze the effect of climate change on the yield and yield risk of irrigated wheat in Iran’s warm and dry regions and to determine fair insurance premium rates based on the associated climatic risks. By incorporating advanced probabilistic modeling and simulation approaches, this research provides a framework for adjusting insurance premiums in response to expected climate changes, thereby facilitating more effective risk management in wheat farming.

 

 

 

Methods

To investigate the impact of climate change on irrigated wheat yield and its implications for insurance premium rates, annual time-series data on wheat yields, along with daily and monthly climate variables, were collected from weather forecast stations between 1991 and 2018. The study employed Moment-based regression models to estimate the conditional probability distribution of wheat yield as a function of climate parameters. Subsequently, mixture probability distribution functions were derived using the yield conditional probability distributions. A simulation approach was then utilized to project future climate scenarios for the 2030s and estimate their effects on the mean and variance of mixture yield distribution and yield premium rates. The results were used to derive region-specific insurance premiums that reflect the climatic risk conditions in warm and dry regions of Iran.

Results

The results revealed that Key climate variables analyzed included total precipitation during the growing season, mean precipitation deficit at the flowering stage, and growth degree days during the growing season. The findings indicate that climate change will significantly impact irrigated wheat yields in Iran’s warm and dry regions. Variations in growth degree days including low, Medium, and High temperatures were found to be critical in determining yield variations. Additionally, The total precipitation during the growing season including germination, tillering, stem elongation, and flowering, and rainfall deficits in the flowering stage, were significant contributors to yield risk. Simulation results for the 2030s suggest that the combined effect of these climate parameters will lead to substantial increases in yield variability, resulting in higher insurance premium rates for irrigated wheat. As a result of these changes, warm and dry regions will experience pronounced yield reductions and heightened risks. As a result, the current uniform insurance premium structure in all regions fails to adequately reflect regional climatic risks, necessitating a shift toward differentiated premium rates based on climate-induced yield variability.

Discussion

The study underscores the urgent need to incorporate climate risk considerations into agricultural insurance policies to enhance the resilience of wheat farmers in warm and dry regions. Implementing region-specific insurance premiums can provide a more accurate reflection of yield risks and encourage farmers to adopt adaptive strategies, such as shifting cultivation practices or selecting more resilient wheat varieties. Additionally, phasing out insurance premium subsidies in high-risk areas could be considered as a policy measure to promote efficient resource allocation and discourage unsustainable wheat production in climate-vulnerable regions. Given the significant impact of climate change on wheat yields in warm and dry regions, policymakers should prioritize the development of adaptive insurance mechanisms that align with projected climatic trends. The results of this study provide valuable insights for policymakers, insurance providers, and farmers in designing risk management strategies that ensure agricultural sustainability in the face of climate change.

Author Contributions

All authors contributed equally to the conceptualization of the article and writing of the original and subsequent drafts.

Data Availability Statement

If the study did not report any data, you might add “Not applicable” here.

Acknowledgements

The authors would like to thank all participants of the present study.

Ethical considerations

The authors avoided data fabrication, falsification, plagiarism, and misconduct.

Conflict of interest

The author declares no conflict of interest.

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