Impact of climate change and irrigation technology advancement on agricultural water use in China

The impact of climate change and irrigation technology advancement on agricultural water use in China is analyzed for the period of 1949-2005. The Palmer Drought Severity Index (PDSI) is adopted to characterize climate change, and the Gross Irrigation Quota (GIQ) is used to examine the relationship between agricultural water use and climate change in China. The results show that the GIQ correlates well with the PDSI in Chinese irrigated areas for the period of 1949-1990. A quantitative relationship between the GIQ and PDSI is statistically regressed; a new GIQ dataset is generated with the PDSI based on this relationship over the period 1949-2005. The generated GIQ data with climate-only information follow the pattern of the actual GIQ for the period 1949-1990. Since 1991, the actual GIQ becomes much smaller than the generated GIQ, indicating that irrigation technology advancement exerts a dominant impact on reducing agricultural water use intensity in China. [PUBLICATION ABSTRACT]