|
|
- 2015
陕西省参考作物蒸发蒸腾量的时空特征及其未来预测
|
Abstract:
【目的】 分析陕西省参考作物蒸发蒸腾量（ET0）的时空特征, 并对未来的ET0进行预测，为制定该地区作物灌溉制度、水资源规划提供参考依据。【方法】 根据陕西省陕北、关中和陕南3个地区18个气象站1961-2000年历年逐日气象资料，采用世界粮农组织（FAO）推荐的Penman-Monteith公式计算历年逐日ET0；依据NCEP再分析数据以及大气环流模式HadCM3输出的大尺度气候要素资料，采用统计降尺度模型（SDSM）对未来A2和B2排放情景下的ET0进行预测。【结果】 1961-2000年，陕西省ET0值在空间上自南至北呈递增趋势，除了7个气象站ET0呈上升趋势外，其余11个气象站平均ET0均呈下降趋势。在A2排放情景下，2011-2040、2041-2070、2071-2099年陕西省ET0的平均值较基准期（1961-2000年）分别增加2.7%，4.9%和8.9%，增幅最大的地区分布在陕南的安康、石泉、略阳和关中华山站以及陕北地区，关中地区增幅较小。2071-2099年陕西省ET0值四季变幅不均匀，其中以冬季的增幅最大。【结论】ET0的持续增长会导致陕西省水资源短缺问题恶化，将进一步影响该地区未来的作物需水量和农业灌溉需水量。
【Objective】This study aimed to analyze temporal and spatial characteristics of reference crop evapotranspiration (ET0) and predict future ET0 in Shaanxi so as to provide foundation for the development of crop irrigation system and water resources plan.【Method】Based on the daily meteorological data from 18 meteorological stations in Shaanxi during 1961-2000,daily ET0 values were calculated using Penman-Monteith equation recommended by FAO.According to the NCEP reanalysis data and GCMs (HadCM3) output data,statistical downscaling model was used to predict future ET0 under the A2 and B2 emission scenarios.【Result】Spatially,ET0 values in Shaanxi had the increasing trend from south to north during 1961-2000.ET0 values at 7 stations increased while at other 11 stations decreased.Under A2 emission scenario,the average ET0 values in 2011-2040,2041-2070,2071-2099 year increased by 2.7%,4.9% and 8.9%,respectively compared to the base period (1961-2000).The areas with largest increase of ET0 were Ankang,Shiquan and Lüeyang stations in Southern Shaanxi,Huashan station in Guanzhong,and stations in Northern Shaanxi.Guanzhong area performed smaller increase range.ET0 values were predicted to change unevenly in 2071-2099 year with the largest increase in winter.【Conclusion】The continued growth of ET0 would increase the shortage of water resources in Shaanxi,further affecting the future water requirements of crops and irrigation
