Climate change and geographic shifts in rice production in China

Climate change can affect crop yield in a given location, and it can also affect where crops are grown. Most assessments of the effect of historical climate change on crop yield has been at the national level, ignoring possibly important subnational variation and climate change adaptation through changes in crop distribution. We analyzed the relationship between growing season temperature, rice yield, and the spatial distribution of rice production in China between 1949 and 2015. Since 1949, rice production in China has moved northwards. Because of this, country level average temperature for rice areas during the growing season was relatively stable, and colder than it would have been without the movement. Temperature has had a very small effect on rice yield at the country level of -0.05 t ha(-1)degrees C-1. However, this masks important subnational variation. Increased temperatures were associated with an increase in rice yield (0-1.0 t ha(-1)degrees C-1) in northern provinces and a decrease (-0.6-0 t ha(-1)degrees C-1) in southern provinces of China. While the estimated overall effect of the northward movement on average rice yield in China was only 162 kg ha(-1), it does illustrate how crop movements can modify climate change effects and can be an emergent adaptation strategy.