Plausible rice yield losses under future climate warming.

Area of Science:

• Agricultural Science
• Climate Science
• Food Security

Background:

• Rice is a critical staple food for over 50% of the global population.
• Predicting rice yield changes is essential for maintaining global food security.
• Climate warming poses a significant challenge to consistent rice production.

Purpose of the Study:

• To compare the sensitivity of rice yield to temperature increases across different methodologies.
• To evaluate the accuracy of statistical, local crop, and global gridded crop models in predicting yield changes.
• To develop a method for constraining global crop model projections of future rice yield.

Main Methods:

• Comparison of rice yield sensitivity to warming from field experiments and three modeling approaches (statistical, local crop, global gridded crop).
• Utilizing field warming experiment data to develop a conditional probability approach.
• Constraining global gridded crop model outputs using experimental data to refine future yield change predictions.

Main Results:

• Field warming experiments and local crop models indicate substantial rice yield losses (-5.2 to -6.3% K⁻¹).
• Statistical and global gridded crop models initially suggested less severe impacts (-0.8 to -2.4% K⁻¹).
• A new constrained model predicts a more severe yield response (-8.3% K⁻¹), reducing ensemble spread by 33%.

Conclusions:

• Without CO2 fertilization, adaptation, and genetic improvements, significant rice yield reductions are likely under intensive climate warming.
• The study highlights discrepancies in model predictions and proposes a method to improve accuracy.
• Findings underscore the vulnerability of rice production to climate change and the need for proactive measures.