沙坡头生态水文学研究进展及水量平衡自动模拟监测系统

在中国科学院野外站网络重点科技基础设施建设项目的支持下,沙坡头沙漠研究试验站建成了以36台大型称重式蒸渗仪为主体的中国北方不同气候带沙区水量平衡自动模拟监测系统——Lysimeter群。概述了沙坡头生态水文学研究进展。介绍了Lysimeter群建设的科学目标、构建思路、建设内容和预期研究方向。Lysimeter群由大型称重式蒸渗仪、各类探头、移动大棚和降水模拟器等组成,具有集成性和唯一性。该平台可全自动模拟控制降水和地下水位,量化植物水分来源;自动监测蒸散发、植物蒸腾、土壤水渗漏、土壤水分、温度和电导率等。该平台的建成将提升在不同尺度上认知中国沙区生态和水文过程、植被重建的生态水文学和环境胁迫生理生态学机理等相关领域的研究能力,回答不同沙区土壤水分植被承载力和人工植被稳定性维持的生态水文阈值等国家在防沙治沙实践中所面临的核心科学问题。     

基于GWR模型的中国区域旅行社业效率空间分异及动力机制分析

基于DEA模型对中国31个省域的旅行社业效率空间分异特征进行了分析,首次运用GWR模型探索交通、资本、人才、信息化和经济动力对区域旅行社业效率影响的空间差异。结果表明：旅行社业效率在空间上具有正相关性和集聚特征,空间格局从“川”字型向“山”字型转变。各动力因子的系数均存在空间非平稳性。资本和人才动力的回归系数在空间分布上从南向北依次递减;经济动力的分布趋势为从北向南依次递减;交通动力对中西部地区旅行社效率提升的促进作用显著于东部地区;信息化动力则在东部地区表现出较强的促进作用。     

中国3A级以上旅游景区空间集聚特征研究

基于中国3 228个3A级以上旅游景区数据分析其空间集聚特征。结果表明,中国3A级以上旅游景区具有典型的“类型极化、区域分化、板块集聚”的分布特征,胡焕庸线两侧景区密度悬殊;中东部地区为凝聚-随机分布,西部地区为凝聚分布,不同区域发育主题和特色不同;5A级景区集聚在经济发达地区,4A级景区沿黄河、长江集中分布,3A级景区多处于东部滨海沿线;历史知名度、自然地理环境、人口经济规模、交通区位条件、审批标准、效仿发展等因素影响较大,循环累积效应显著。据此提出“区域平衡、跨区协调、分类优化”的发展建议。     

基于北极黄河站观测的日侧极光研究新进展

回顾了基于中国黄河站全天空极光观测对日侧弥散极光与喉区极光研究的最新进展。首先,利用黄河站极光观测,对日侧弥散极光展开系统性分类与统计研究,对这一重要空间物理现象取得新认识,指出日侧弥散极光对研究日侧外磁层冷等离子体的分布、形成及磁鞘粒子进入磁层都具有重要启示作用;同时发现并定义了一种新型分立极光结构——喉区极光,并推断其可能对应磁层顶的局地变形。喉区极光是指发生在电离层对流喉区附近、从极光卵赤道侧向低纬方向延伸出来的分立极光结构。全天空极光观测表明喉区极光走向大致与电离层对流方向一致。之后,观测验证了喉区极光对应磁层顶局地内陷式变形的推测;统计发现喉区极光是一种非常高发的现象,对应的磁层顶变形尺度可达2—3 Re,并指出这种变形最可能由磁鞘高速流冲击磁层顶产生;发现在喉区极光产生过程中还可能触发磁重联;证实伴随喉区极光的产生,磁鞘粒子会进入磁层并诱发产生一种新型弥散极光。通过喉区极光研究,可以将已有的磁鞘瞬态过程研究和触发式磁重联研究有机地结合在一起,对太阳风-磁层耦合过程形成一种新的认识,即:在磁鞘中局地产生(而不是存在于太阳风中)的瞬态过程可以在日下点附近频繁地导致磁层顶局地变形、触发重联、引发系列地球空间效应,可能对太阳风-磁层耦合具有不可忽略的重要性。以此为基础,讨论了日侧极光研究引出的新课题。     

Village-level multidimensional poverty measurement in China: Where and how

Village is an important implementation unit of national poverty alleviation and development strategies of rural China, and identifying the poverty degree, poverty type and poverty contributing factors of each poverty-stricken village is the precondition and guarantee of taking targeted measures in poverty alleviation strategies of China. To respond it, we construct a village-level multidimensional poverty measuring model, and use indicator contribution degree indices and linear regression method to explore poverty factors, while adopting Least Square Error (LSE) model and spatial econometric analysis model to identify the villages’ poverty types and poverty difference. The case study shows that: (1) Spatially, there is obvious territoriality in the distribution of poverty-stricken villages, and the poverty-stricken villages are concentrated in contiguous poverty-stricken areas. The areas with the highest VPI, in a descending order, are Gansu, Yunnan, Guizhou, Guangxi, Hunan, Qinghai, Sichuan, and Xinjiang. (2) The main factors contributing to the poverty of poverty-stricken villages in rural China include road construction, terrain type, frequency of natural disasters, per capita net income, labor force ratio, and cultural quality of labor force. The main causes of poverty include underdeveloped road construction conditions, frequent natural disasters, low level of income, and labor conditions. (3) Chinese poverty-stricken villages include six main subtypes, and most poverty-stricken villages are affected by multiple poverty-forming factors, reflected by a relatively high proportion of the three-factor dominant type, four-factor coordinative type, and five-factor combinative type. (4) There exist significant poverty differences in terms of geographical location and policy support, and the governments still need to carry out targeted poverty alleviation measures according to local conditions. The research can not only draw a macro overall poverty-reduction outline of impoverished villages in China, but also depict the specific poverty characteristics of each village, helping the government departments of poverty alleviation at all levels to mobilize all kinds of anti-poverty resources.     

Random encounters in probabilistic time geography

Probabilistic time geography considers the encounter of moving agents to be random; therefore, a quantitative time geography analysis must consider the actual encounter probability. The existing algorithm of encounter probability is oriented over a discrete space and is sensitive to the unit definition of a virtual grid; thus, it is not suitable for continuous space. For this reason, a new method is presented in this paper for the encounter of two moving agents in continuous space. When the encounters are less than a specified distance threshold apart, an encounter event occurs based on the probability of the product, which is calculated by their respective probability density functions over their respective potential location areas. This probability provides a quantitative basis for predicting the likelihood of two agents meeting, as well as the location of this meeting point. Finally, the validity of the proposed model is verified by an experiment, which uses tracking data to calculate the encounter probabilities of three zebras and analyse the distribution characteristics of these probabilities over time and space.     

Local meteorology in a northern Himalayan valley near Mount Everest and its response to seasonal transitions

An automatic weather station(AWS) has been installed at the Qomolangma Station of the China Academy of Sciences(QOMS) since 2005, in a northern Himalayan valley near Mount Everest, with an altitude of 4,270 m a.s.l.. Nine years of meteorological records(2006–2014) from the automatic weather station(AWS) were analyzed in this study, aiming to understand the response of local weather to the seasonal transition on the northern slopes of Mount Everest, with consideration of the movement of the subtropical jet(STJ) and the onset of the Indian Summer Monsoon(ISM). We found:(1) Both the synoptic circulation and the orography have a profound influence on the local weather, especially the local circulation.(2) Southwesterly(SW) and southeasterly(SE) winds prevail alternately at QOMS in the afternoon through the year. The SW wind was driven by the STJ during the non-monsoon months, while the SE was induced by the trans-Himalayan flow through the Arun Valley, a major valley to the east of Mount Everest, under a background of weak westerly winds aloft.(3) The response of air temperature(T) and specific humidity(q) to the monsoon onset is not as marked as that of the nearsurface winds. The q increases gradually and reaches a maximum in July when the rainy period begins.(4) The alternation between the SW wind at QOMS and the afternoon SE wind in the pre-monsoon season signals the northward shift of the STJ and imminent monsoon onset. The average interval between these two events is 14 days.     

公路积水阻断与降雨关系的探讨

利用2011—2013年全国公路积水阻断资料,分析了公路积水阻断的时空分布特征,并对公路积水阻断与不同时效降雨的关系进行了探讨。结果表明,公路积水阻断事件发生时间主要集中在5—9月,其中7月最为频繁,公路积水阻断事件以07:00—14:00为第一多发时段,16:00—20:00为次多发时段。公路积水阻断与前24h内的降水关系更为密切。区域不同,公路积水阻断随各强度降水变化的特点也不尽相同。经过开立方根处理后的降水因子与公路积水阻断发生的频次服从于高斯分布。其中,区域1公路积水阻断与处理后的1h最大降水因子关系密切,相关系数大于0.91;区域2和3公路积水阻断与处理后的6h最大降水因子关系密切,相关系数均在0.8以上;区域4公路积水阻断则与处理后的24h最大降水因子关系密切,相关系数在0.75左右。对于任何一个区域,诱发公路积水阻断的不同时效降水都处于一个较大的空间。对于给定的降水量只能判断公路积水阻断发生的可能性大小。     

基于MICAPS4的智能网格预报平台设计与实现

随着我国智能网格预报业务的开展,海量高分辨率客观数据需要便捷的分析显示及产品制作平台高效处理。该文基于MICAPS4（Meteorological Information Comprehensive Analysis and Processing System Version 4.0,人机交互气象信息处理和天气预报制作系统）设计并实现智能网格预报平台,采用MVVM（模型-视图-视图模型,model-view-viewmodel）设计模式,实现业务逻辑与视图的分离,通过对各子功能模块的划分,降低模块之间的耦合度,具有良好的可扩展性。平台实现了高分辨率网格预报数据的显示分析和产品输出,开发了基于等值线、网格、关键点等智能化预报制作工具,集成了降水时间拆分、温度极值订正等客观预报方法,开发了降水、温度、相对湿度等要素一致性处理方法,可有效帮助预报员提高工作效率,同时能够确保产品之间的一致性。平台继承MICAPS4的微内核组件服务、高性能渲染引擎和开放式插件扩展管理等优良特性,实现面向智能网格预报的业务编排、智能编辑和算法集成。目前,该平台已经实现业务应用,为全国智能网格预报业务提供重要支撑。     

1983—2015年湖南雨凇时空分布特征及影响因子

采用经验正交函数（EOF）并对1983—2015年湖南省95个地面气象站的雨凇观测资料以及与北半球海冰和西太平洋和东北印度洋海温资料的相关性进行分析。结果表明：湖南各站年均雨凇频次为219次,总体呈现北少南多、山区北侧少南侧多、平原地带少的分布特点;雨凇频次呈逐年下降趋势,且在湖南中北部地区下降趋势显著;湖南雨凇主要发生于相对湿度较大、极大风为偏北风且风速较小、最低气温在-3~0 ℃、最高气温在0~4 ℃的环境中。冬季同期（12月至次年2月）,北地群岛以东至白令海峡以北海域海冰密度和湖南雨凇频次的相关关系为显著正相关关系,而西北太平洋海温和湖南雨凇频次的显著负相关区域表现为C型分布。