Projected high-resolution ETo spatiotemporal variation under future climate change and paddy area expansion in the Sanjiang Plain, Northeast China

Abstract

Study region: This research studies Sanjiang Plain because of its past drastic climate change and paddy area expansion, and future paddy area continue to expand supported by water conservancy project. Study focus: This research focuses on projecting high-resolution reference crop evapotranspiration (ETo) spatiotemporal variation under future climate and underlying surface change, and quantified its coupled effects. New hydrological insights for the region: The integrated framework of Patch-generating Land Use Simulation, Weather Research and Forecasting, and bias-corrected CMIP6 dataset is proposed to consider the integration of future paddy area expansion and climate change impacts on ETo. Results showed that future paddy area will continue to increase, but it is much lower than past expansion scale. The average temperature, average relative humidity, and total ETo show an increasing trend. The spatial distribution is characterized by temperature and ETo reaches its highest value in central region, and decreases along the surrounding area, but relative humidity is diametrically opposed. The central regions have significant change in temperature, relative humidity, and ETo, deserving further attention. The coupled effect of paddy expansion and climate change is reflected in increasing average temperature (0.95–1.94 °C) and total ETo (19–39.96 mm), but decreasing average wind speed (0.09–0.12 m/s).

Keywords

• High-resolution ETo
• Spatiotemporal variation
• Integrated framework
• Climate change
• Paddy area expansion