基于NEX-GDDP降尺度数据的山东省夏玉米生育期极端高温时空特征研究

Study of Spatio-temporal Characteristics of Extreme High Temperature during Corn Growing Season in Shandong Based on NEX-GDDP Downscaled Data

极端高温灾害严重,在未来很有可能会加剧。研究基于NEX-GDDP高时空分辨率降尺度数据及历史观测数据,将35℃作为极端高温阈值,对当前及未来不同情景下夏玉米生育期(6-9月)极端高温时空分布特征进行分析。结果显示:在各个时期、各情景下山东省日最高气温空间上都呈现出东部沿海较低向西部内陆地区逐渐升高的趋势,随时间逐渐增高,在RCP8.5排放情景下增加更显著,且西部地区较东部沿海地区增加幅度大;极端高温日数同样呈现增加的趋势,特别在未来远期RCP8.5排放情景下增加迅速,超过50%地区达到80d以上。NEX-GDDP数据具有较好的应用效果,未来极端高温灾害频发,夏玉米生产将面临严重威胁。

Extreme high temperature events are becoming serious under climate change and this trend will continue.Based on the high spatio-temporal resolution dataset of NASA Earth Exchange(NEX)Global Daily Downscaled Projections(GDDP)and historical observation data,the spatio-temporal distribution characteristics of extreme high temperature events at present and potential climate change were studied.The results shown that,the average daily maximum temperature at each time period and emission scenarios was smaller in the eastern coastal area,and gradually increased to the western part of Shandong.Daily maximum temperature increased with time.This trend was more obvious under Representative Concentration Pathway(RCP)8.5,and the temperature increased range was larger in western part than eastern part.The extreme high temperature days also had an increasing trend with time,especially under RCP8.5 during 2070-2099.Over half of Shandong the number of extreme high temperature days over 80.The NEX-GDDP dataset has a good performance.The extreme high temperature disaster will worsen,and summer corn will face a major threaten.