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采用1991—2017年BCC_CSM1.1m季节预测模式的月降水预测数据及福建省前汛期(4—6月)66个国家气象站降水资料,利用距平相关系数(ACC)、时间相关系数(TCC)、平均方差技巧评分(MSSS)和趋势异常综合评分(Ps)等评估方法,检验评估了提前0、1、2和5个月模式对福建省前汛期降水的预测能力。采用系统偏差、一元线性回归和EOF-相似误差(EOFL和EOFNL)等4种统计方法对回报结果进行订正,并进行效果检验。BCC_CSM1.1m在不同起报时间对福建省前汛期降水的预测均能抓住降水的前两个主模态:全省一致和南北反向分布的空间特征,但预测的气候平均值较实况存在负偏差。模式在不同起报时间对前汛期降水预测的TCC高技巧区主要位于福建省北部,ACC技巧和Ps评分存在比较大的年际差异,负系统偏差的存在使得MSSS技巧不高。经订正后,模式的预测能力得到明显提升。系统偏差、线性回归、EOF相似误差线性和非线性订正方法提前2个月起报的2011—2017年平均Ps评分分别提高5.9、3.5、6.7和7.8分;不同起报时间线性回归订正的2011—2017年平均ACC技巧分别提高0.02、0.21、0.12和0.11;上述4种方法订正的MSSS评分均有了显著提高,其中系统偏差和线性回归订正后达正技巧。综合而言,线性回归订正较其他3种订正方法表现出更为稳定的订正技巧。 相似文献
264.
YIShu-ping CHIBao-ming LIZhi-jun LIZhi-ping 《东北亚地学研究》2004,7(1):70-73
To use the water resources reasonably in the midstream of Yinma River is of great significance to Changchun City which is short of water. With the runoff data of physical measuring, the paper analyses the characteristics surface rtmoff of the area, by means of the groundwater flow numerical simulation, and represents the characteristics of the groundwater runoff in the area. Based on combination analyses of the two runoffs, the authors point out the problem of the water resources use in this area and bring forward a resolution of conjunctive regulation and storage of the surface water and groundwater. 相似文献
265.
利用广州市5个国家气象观测站和122个区域自动气象站的逐日降水量监测数据,通过线性趋势分析、M-K检验、小波分析和主成分分析等统计办法,研究广州市“龙舟水”的时空分布特征,结果表明:(1)广州全市和花都近30年“龙舟水”雨量整体呈上升趋势,且花都上升趋势略高于广州平均,花都区“龙舟水”异常年与广州其它地区并不一定同步。(2)广州全市逐年“龙舟水”以7~9年周期为主,2007年以前有4年左右的小周期,之后存在2~3年周期,且特征趋于不明显,花都“龙舟水”雨量变化存在8~10年周期,2007年以前存在4~6年小周期,之后转变为3~4年小周期。(3)广州全市2005和2014年“龙舟水”雨量出现增多突变,2008年又出现了雨量减少的突变;花都“龙舟水”雨量在2014年出现雨量增加的突变,2017年“龙舟水”显著增加。(4)广州“龙舟水”雨量大值区主要位于北部偏东一带,从化和花都北部、白云南部、天河、番禺东部和南部、南沙北部降水年变化相对较为稳定,其余地区逐年变化幅度相对较大。(5)对广州逐年“龙舟水”标准化距平场作EOF分析结果表明,前4个模态解释方差共占91.2%,分别为全市一致偏多或偏少型、南北偶极型、南北向四极型、东西向三极型。 相似文献
266.
中国可持续发展信息共享是我国为探索国家层次上信息共享的示范,旨在向政府部门与社会公众提供可持续发展各专题的数据与信息服务,数据仓库的建设是实现信息共享与服务的支撑和基础。本文首先通过数据提取、数据转化、数据清洗以及创建元数据和数据字典等步骤,对多源异构的中国可持续发展数据进行了体系化扩展和标准化改造,为数据进入仓库奠定了基础。之后通过一套新颖的数据多维组织模式,即基于可持续发展信息分类与编码的数据组织、基于元数据和数据字典的数据组织、基于空间和时间的数据组织及面向数据集市的部门级数据组织这四种方式的综合应用,实现了海量可持续发展数据的组织和管理,建立了一个集中式的可持续发展数据仓库。最后介绍了数据仓库管理平台,并对基于该数据仓库的可持续发展数据共享和网络服务进行了展示。中国可持续发展数据仓库的建立为中国可持续发展信息共享和服务提供了良好数据基础,对国家级大型信息共享工程的建设具有一定的借鉴意义。 相似文献
267.
Intra-annual variability of satellite observed surface albedo associated with typical land cover types in China 总被引:2,自引:0,他引:2
Surface albedo is a primary causative variable associated with the process of surface energy exchange. Numerous studies have examined diurnal variation of surface albedo at a regional scale; however, few studies have analyzed the intra-annual variations of surface albedo in concurrence with different land cover types. In this study, we amalgamated surface albedo product data (MCD43) from 2001 to 2008, land-use data (in 2000 and 2008) and land cover data (in 2000); quantitative analyses of surface albedo variation pertaining to diverse land cover types and the effect of the presence/absence of ground snow were undertaken. Results indicate that intra-annual surface albedo values exhibit flat Gaussian or triangular distributions depending upon land cover types. During snow-free periods, satellite observed surface albedo associated with the non-growing season was lower than that associated with the growing season. Satellite observed surface albedo during the presence of ground snow period was 2-4 times higher than that observed during snow-free periods. Surface albedo reference values in typical land cover types have been calculated; notably, grassland, cropland and built-up land were associated with higher surface albedo reference values than barren while ground snow was present. Irrespective of land cover types, the lowest surface albedo reference values were associated with forested areas. Proposed reference values may prove extremely useful in diverse research areas, including ecological modeling, land surface process modeling and radiation energy balance applications. 相似文献
268.
Urban land cover has major impacts on a city’s ecosystem services and the inherent quality of its urban residential environment. The spatio-temporal distribution of impervious surface area and green areas in Chinese cities has exhibited a significantly marked difference in comparison with USA cities. This study focused on monitoring and comparing the spatio-temporal dynamics, land cover patterns and characteristics of functional regions in six Chinese(n=3) and USA(n=3) cities. The study data were collated from Landsat TM/MSS imagery during the period 1978–2010. Results indicate that Chinese cities have developed compactly over the past three decades, while development has been notably dispersed among USA cities. Mean vegetation coverage in USA cities is approximately 2.2 times that found amongst Chinese urban agglomerations. Land use types within Chinese cities are significantly more complex, with a higher density of impervious surface area. Conversely, the central business district(CBD) and residential areas within USA cities were comprised of a lower proportion of impervious surface area and a higher proportion of green land. Results may be used to contribute to future urban planning and administration efforts in both China and the USA. 相似文献
269.
Surface albedo is a primary causative variable associated with the process of surface energy exchange. Numerous studies have examined diurnal variation of surface albedo at a regional scale; however, few studies have analyzed the intra-annual variations of surface albedo in concurrence with different land cover types. In this study, we amalgamated surface albedo product data(MCD43) from 2001 to 2008, land-use data(in 2000 and 2008) and land cover data(in 2000); quantitative analyses of surface albedo variation pertaining to diverse land cover types and the effect of the presence/absence of ground snow were undertaken. Results indicate that intra-annual surface albedo values exhibit flat Gaussian or triangular distributions depending upon land cover types. During snow-free periods, satellite observed surface albedo associated with the non-growing season was lower than that associated with the growing season. Satellite observed surface albedo during the presence of ground snow period was 2–4 times higher than that observed during snow-free periods. Surface albedo reference values in typical land cover types have been calculated; notably, grassland, cropland and built-up land were associated with higher surface albedo reference values than barren while ground snow was present. Irrespective of land cover types, the lowest surface albedo reference values were associated with forested areas. Proposed reference values may prove extremely useful in diverse research areas, including ecological modeling, land surface process modeling and radiation energy balance applications. 相似文献
270.