Impact of global warming on Chinese wheat productivity

This paper argues that climate change continues to have major impact on crop productivity all over the world. While many researchers have evaluated the possible impact of global warming on crop yields using mainly indirect crop simulation models, there are relatively few direct assessments on the impact of observed climate change on past crop yield and growth.

The report analyses a 1979-2000 Chinese crop-specific panel dataset to investigate the climate impact on Chinese wheat yield growth.

The analysis finds that:

• a one percent increase in wheat growing season temperature reduces wheat yields by about 0.3 percent
• this negative impact is less severe than those reported in other regions
• rising temperature over the past two decades accounts for a 2.4 percent decline in wheat yields in China while the majority of the wheat yield growth, 75 percent, comes from increased use of physical inputs

The paper concludes that:

• climate change does have a measurable negative impact on wheat productivity
• this negative impact would probably become worse with accelerating change of future climate
• there is a need to consider climate change and its effects on crop productivity in order to meet the food security goals in China as well as in other developing countries
• there is also a need to extend such studies to other regions, in particular to food insecure countries where climate change would have the most severe adverse impact on crop productivity
• the necessity of including such major influencing factors as physical inputs into the crop yield-climate function in order to have an accurate estimation of climate impact on crop yields