Extended crop yield meta-analysis data do not support upward SCC revision

Area of Science:

• Climate change economics
• Agricultural science
• Environmental policy

Background:

• The Social Cost of Carbon (SCC) estimate was recently increased significantly by the Biden Administration.
• This increase was partly based on projections of global crop yield declines due to warming.
• The original projections utilized a meta-analysis database from 2014 with substantial data limitations.

Purpose of the Study:

• To re-examine the meta-analysis database used for SCC calculations.
• To assess the impact of data completeness on projected global crop yield changes under warming scenarios.
• To provide a more accurate estimate of climate change impacts on agriculture.

Main Methods:

• Re-analyzing the original meta-analysis dataset by recovering missing data points.
• Expanding the dataset from 862 to 1222 records through data recovery.
• Performing multivariate regression modeling on the augmented dataset.

Main Results:

• The original dataset suggested yield declines for all crops even at low warming levels.
• The re-analyzed, larger dataset indicates zero or positive global average yield changes.
• These positive or neutral yield changes persist even up to 5°C of warming.

Conclusions:

• The re-analysis suggests that the impact of warming on global crop yields may be less severe than previously estimated.
• The findings challenge the basis for the recent increase in the Social Cost of Carbon.
• Further research with comprehensive data is needed to accurately model climate change impacts on agriculture.