Introduction
Climate change represents one of the pivotal challenges of the 21st century, markedly impacting global food production and security (Tagwi, 2022). The interplay of rising temperatures, shifting precipitation dynamics, and increased carbon dioxide levels significantly influences agricultural outputs. These climatic alterations not only diminish agricultural yields but also disrupt the food supply chain, consequently driving up prices and limiting access to essential food resources (Demirhan, 2020). Among the various factors impacting food production, carbon dioxide emissions stand out due to their role as a primary greenhouse gas. They contribute to global warming and fundamentally alter plant growth dynamics. While it is documented that elevated CO2 levels can enhance photosynthetic rates, the detrimental effects of increased temperatures and reduced precipitation typically overshadow these potential benefits (Ayyildiz & Erdal, 2021). The nexus between atmospheric CO2 concentration and agricultural productivity underscores the complexity of climate-related challenges faced by the agricultural sector. Research indicates that anthropogenic activities, particularly in the agricultural sector, have significantly elevated greenhouse gas concentrations in the atmosphere, directly contributing to global warming. The agricultural industry is vital for both economic and social development globally, and it plays a crucial role in addressing hunger and ensuring food security—objectives that align with the overarching goals of sustainable development as recognized internationally (Hosseini et al., 2013). However, this sector is increasingly vulnerable to the impacts of climate change, which presents an existential threat to agricultural productivity and global food security, particularly in recent decades. The Food and Agriculture Organization (FAO) projects that climate change may reduce agricultural output by 10 to 25 percent in certain at-risk regions by 2050, posing a severe challenge to food security worldwide. Furthermore, in 2020, approximately 33% of global agricultural production was adversely impacted by climate change, underscoring the critical need for adaptive strategies in agricultural practices (Florea et al., 2020). This study aims to create a comprehensive framework that links climatic factors (temperature, precipitation, cultivated area) with economic variables (agricultural credit, trade liberalization) and social aspects (agricultural labor force) to analyze their impact on Iran’s agricultural production index. By addressing gaps in previous research, this model will evaluate both long-term and short-term relationships, providing valuable insights and policy recommendations to combat the negative effects of climate change on food security in Iran.
Material and Method
This study analyzes annual data from Iran for the period 1990-2022 to investigate key determinants impacting food security. The analysis incorporates both climatic and non-climatic factors, including mean annual temperature (TEM), mean annual precipitation (RAIN), carbon dioxide emissions (CO2), agricultural sector credit allocation (CREDIT), energy consumption (EN), land area dedicated to agricultural crops (LAND), the agricultural labor force metrics (AGEM), trade liberalization indices (TR), and the agricultural production index (API).
The ARDL method allows for the simultaneous examination of long-run and short-run effects between variables, addressing the limitations of the Engle-Granger method. Notably, studies by Pesaran et al. (1996) and Pesaran & Shin (1996) highlight the ARDL approach's ability to analyze relationships without needing to determine the direction of causality. It accommodates variables that are stationary at different levels, avoiding the need to separate them into stationary groups. This method can produce unbiased and efficient estimates, as it typically bypasses issues like serial autocorrelation and endogeneity (Sidiki, 2000).
Result and Discussion
This study reveals that climate change is affecting food production in Iran differently. Increased temperatures have a significant negative impact on agriculture, with a coefficient of -0.445, aligning with findings that suggest higher temps reduce crop yields due to increased evapotranspiration, lower soil moisture, and heat stress. Conversely, precipitation has a positive impact, with a significant coefficient of 0.556, emphasizing the importance of water resources for agriculture. Additionally, carbon dioxide emissions negatively affect agricultural production, with estimates indicating that a 1% increase in emissions could decrease production by 0.011%. Agricultural labor (coefficient of 1.540) remains crucial for Iran's agricultural production index. However, declining employment in this sector underscores the need for mechanization and improved labor productivity. The study also reveals a negative impact of trade liberalization (coefficient of -1.081) on food production, indicating a 1.081 percent decrease in the agricultural production index with increased trade relations, assuming other conditions remain constant. Short-term changes in crop area, credit, energy consumption, rainfall, temperature, labor, and trade liberalization significantly impact food production. The coefficient of crop area (0.955) highlights the importance of enhancing agricultural infrastructure. Additionally, the positive effect of credit (0.198) underscores the vital role of financial policies in supporting agriculture. Access to credit helps farmers expand operations and improve productivity through investments in machinery and technology. In Iran, where agriculture is crucial for food security, targeted credit policies can strengthen production capacities and reduce reliance on imports. These findings align with existing literature on food security and agricultural development. The precipitation coefficient is 0.146, indicating a significant positive effect on agricultural yields, particularly in arid regions of Iran, where it is a key water source. Conversely, the temperature coefficient is -0.428, suggesting that higher temperatures negatively impact food production. The error correction term with a coefficient of -0.605 suggests that approximately 60 percent of the short-run imbalance adjusts towards long-run equilibrium each period.
Conclusion
The analysis revealed that rising temperatures and increased carbon dioxide levels adversely affect agricultural production in the long term. Notably, while the temperature coefficient was not statistically significant over extended periods, this may suggest the presence of nonlinear dynamics or the moderating effects of additional variables. Conversely, precipitation demonstrated a positive and statistically significant effect on agricultural output in both the short and long term. The findings underscore that the influence of climatic variables on agricultural production intensifies over time, likely attributable to cumulative mechanisms such as progressive soil degradation, loss of biodiversity, and heightened environmental stressors. In light of these outcomes, it is imperative to pursue adaptive strategies in agriculture that address climate change. This includes the implementation of advanced irrigation systems, promotion of sustainable agricultural practices to mitigate alterations in precipitation patterns, investment in climate-resilient research aimed at developing heat- and drought-resistant crop varieties, and the modification of crop patterns to manage pollution emissions. Such measures are essential for alleviating the adverse impacts of climate change on food security.
Keywords: Climate change, energy consumption, CO2 emissions, agricultural production, trade openness.