摘要
气候变化的研究依赖于可靠的气候数据。英国东英吉利大学气候研究中心推出的一套依据观测资料插值所得的月平均气候数据集(CRU),是目前使用较为广泛、质量较高的气候数据集。气候观测数据大多始于1950年,已有的研究也表明CRU数据在1950年后更具参考价值,但该数据集在1950年之前的可靠性不清楚。由于1950年之前缺乏器测数据,本研究使用树轮资料,对比每十年树轮重建温度(降水)与树轮附近CRU格点上的温度(降水)的距平和趋势的同号率,来评价CRU温度(降水)数据在不同地区的数据质量(可靠性),由此发现从1930年代开始,CRU温度数据在欧洲和中西伯利亚可信度较高;从1940年代开始,CRU温度数据在美国东部可信度较高;从1940年代开始,CRU降水数据在美国东部与西西伯利亚可信度较高。研究发现,气象站密度对CRU数据质量有很大影响;在气象站密度小的地区,CRU温度或降水数据与树轮序列的差异更为显著,气候数据质量偏低;而数据可信度较高的年代和地区,气象站密度往往较大。
Climate change studies depend on reliable climate data,though climate observation history is short and mostly start from the 1950s.By interpolating observations,the Climatic Research Unit(CRU)of the University of East Anglia has created a monthly-mean climate dataset of high quality,which is currently widely used.Previous studies have demonstrated that the CRU data became more reliable after 1950.However,the reliability of the dataset before 1950 is unclear.Here,we use tree-ring data(from National Climatic Data Center's Paleoclimatology Data)to evaluate the quality and reliability of CRU data in different regions of the North Hemisphere on a decade time scale.Tree-ring data are detrended by the spline function.If one of the correlation coefficients is over 90%significant between tree-ring data and CRU temperature(precipitation)data on the nearest four grid points after 1950,then it is grouped into temperature-sensitive(precipitation-sensitive).Based on the distribution of tree-ring sites and topography,the North Hemisphere is divided into eight regions:high latitudes of North America,Western America,Eastern America,Europe,Western Siberia,Central Siberia,Eastern Siberia,and Altay.We assess the consistency between anomalies and trends in temperature-sensitive(precipitation-sensitive)tree-ring data and CRU temperature(precipitation)on the decadal timescales,by calculating the ratio of those with concordant variations(relative to the climatology from May to September over 1961~1990).Our comparison reveals that the reliability of CRU temperature data in Europe and Central Siberia has generally been high after the 1930s.After the 1940s,the reliability of CRU temperature improves again in Eastern America,and the reliability of CRU precipitation increases in Eastern America and Western Siberia.The density of meteorology stations largely influences the quality of CRU data.In a region with low-density meteorology stations,the difference between CRU data and tree-ring data is more remarkable,and the reliability of CRU data
作者
王锡津
方克艳
张仲石
WANG Xijin;FANG Keyan;ZHANG Zhongshi(Department of Atmospheric Science,School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430074,Hubei;Centre for Severe Weather and Climate and Hydro-Geological Hazards,Wuhan 430074,Hubei;Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education,Fujian Normal University,Fuzhou 350117,Fujian;School of Geographic Science,Nantong University,Nantong 226019,Jiangsu)
出处
《第四纪研究》
CAS
CSCD
北大核心
2023年第5期1254-1268,共15页
Quaternary Sciences
基金
国家重点研发计划项目(批准号:2018YFA0605602)资助。
