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为了得出雾霾气象成因机制、影响因素和时空分布特征,以石家庄市区与郊县为研究区域,将2013年9月至2016年12月石家庄市各市区、郊县的PM2.5历史监测数据中的有效数据进行了数据分析处理得到雾霾浓度数据,还有温度、降水、风速、地形和人口密度等数据,运用GIS分析的方法,模拟绘制石家庄雾霾的时空分布图、雾霾与各影响因子的专题对比图,得到雾霾形成机制的因子、雾霾的时空分布规律、雾霾季节变化特征、雾霾与地形间的关系等;运用数据分析软件OriginPro8.SR3分析雾霾浓度与风速数据、降雨数据、温度数据间的相关性。 相似文献
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从太湖流域旱涝史料看历史气候信息处理 总被引:15,自引:1,他引:14
历史气候信息处理建立在信息提取的基础上,目的在于建立一套方法,将定性的历史气候信息转化为气候变化参数,并消除各种不均—性,从而建立历史气候序列。本文着重介绍建立太湖流域历史旱涝等级序列的方法与步骤: 1)确立信息源,建立信息网络;2)站点等级的确定与订正;3)弱信息处理;4)信息的综合。 相似文献
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针对遥感影像共享服务的应用需求,提出基于中间件技术的影像数据共享方法;设计基于中间件技术的影像数据服务模式。通过实验实现支持多用户并发访问的服务原型,验证基于中间件技术的影像数据服务方法的可行性并给出进一步研究的方向。 相似文献
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The response of natural vegetation to climate change is of global concern. In this research, an aggregated Holdridge Life Zone System was used to study the possible response of life zones in China under doubled atmospheric CO2 concentration with the input climatic parameters at 0.5×0.5° resolution of longitude and latitude from NCAR regional climate model 2 (RegCM2) coupled with the CSIRO global climate model. The results indicate that the latitudinal distribution of life zones would become irregular because of the complicated climate change. In particular, new life zones, such as subtropical desert (SD), tropical desert (TDE) and tropical thorn woodland (TTW), would appear. Subtropical evergreen broadleaved forest (SEBF), tropical rainforest and monsoon forest (TRF), SD, TDE and TTW zones would appear in the northeastern China. Cool-temperate mixed coniferous and broadleaved forest (CMC) and warm-temperate deciduous broadleaved forest (WDBF) zones would appear at latitudes 25–35°N. The temperate desert (TD) in the western China would become Tibetan high-cold plateau (THP), SEBF, WDBF and temperate steppe (TS), and a large part of THP would be replaced by TRF, TDE, SEBF, TS and TTW. The relative area (distribution area/total terrestrial area) of CMC, TRF, TDE and TTW zone would increase about 3%, 21%, 3% and 6%, respectively. However, the relative area of SEBF, TS, TD and THP would decrease about 5%, 3%, 19% and 4%, respectively. In all, the relative area of forests (CCF, CMC, WDBF, SEBF, TRF) would increase about 15%, but the relative area of desert (TD, SD, TDE, and TTW) and THP would decrease about 9% and 4%, respectively. Therefore, responses of different life zones in China to climate change would be dramatic, and nationwide corridors should be considered for the conservation of migrating species under climate change. 相似文献
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The characteristics of Asian dust events in Northeast Asia during the springtime from 1993 to 2004 总被引:3,自引:1,他引:2
The characteristics of Asian dust events that occurred in Northeast Asia during the springtime from 1993 to 2004 are investigated using 3-hourly SYNOP reports (World Meteorological Organization). Occurrences of blowing sand and dust storm are low in 1997 and 1999, but have increased rapidly since 2000. The maximum occurrence was recorded in 2002. Wind velocity of 6.5 m s− 1 as a threshold wind velocity is not so exactly consistent with the occurrence of blowing sand. However, wind velocity of 14 m s− 1 as a strong wind causing dust storm had similar tendency to those of dust storm and Dust Storm Index.Source regions of Asian dust are divided into three regions (A: dry arid, B: semi-arid, and C: cultivated), based upon the occurrence of blowing sand and dust storm. Eight meteorological stations are selected in three regions, which have frequent occurrences of blowing sand. Source regions of Asian dust that affect the Korean peninsula are gradually extending eastward. Positive anomalies of NDVI occurred in 1994, 1995, and 1998 when temperature was high and precipitation was heavy. However, the frequent occurrence of the dust phenomena is not always consistent with lots of vegetation, high temperature, and much precipitation in this study. 相似文献
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Virtual Huanghe River System: Framework and Technology 总被引:2,自引:0,他引:2
LU Heli LIU Guifang SUN Jiulin 《中国地理科学(英文版)》2006,16(3):255-259
1 Introduction Huanghe (Yellow) River basin is located in 32°–42°N, 96°–119°E. The area of the catchment is more than 752,000km2. The river is 5464km long with a drop in elevation of 4830m. Among the whole area, the moun- tainous and stone area accounts for 29%, loess and hills area 46%, sandy area 11% and plain area 14%, respec- tively. Different natural landscapes exist in this area. The Huanghe River flows through the Loess Plateau, where the soil is eroded seriously (Wang, 2002;… 相似文献
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We examine possible locations for the primordial disk of the Edgeworth-Kuiper Belt (EKB), using several subsets of the known objects as markers of the total mass distribution. Using a secular perturbation theory, we find that the primordial plane of the EKB could have remained thin enough to escape detection only if it is clustered very closely about the invariable plane of the Solar System. 相似文献
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科技进步是测绘事业发展的动力 ,讨论运用科技进步的评价指标 ,对测绘单位的科技进步速度和对经济增长的贡献等进行测算和分析 ,可以为测绘规划管理及决策提供参考。 相似文献