欧亚黄土沉积环境对比研究

本文对采自中国、法国、比利时等国43块黄土样品进行实验室处理后,分析对比了它们在碳酸盐含量、粒度组成、重矿物组成及粘土矿物成分方面的共同特性及差异性。结果表明,中国黄土碳酸盐含量稳定,西欧不同类型的黄土碳酸盐含量差别很大。在粒度组成上,欧亚黄土并没有本质的差别,但西欧不同层位的黄土粒度组成呈有规律变化。对西欧重矿物的分析可以追溯黄土的物质来源,粘土矿物含量在欧亚不同黄土中也有差别。比较结果说明,欧洲的黄土堆积受第四纪冰期、间冰期的气候波动影响较大,中国黄土在堆积期间始终处在干旱、半干旱的气候条件下。     

中国与俄罗斯及中亚地区的贸易格局分析

作为上海合作组织成员国及丝绸之路经济带的重点区域,俄罗斯及中亚地区与中国经贸关系日益密切,对中国内陆开放及地缘政治安全具有重大意义。利用贸易强度指数、贸易互补性指数、出口集中指数等,对1992-2012年中国与俄罗斯及中亚地区的贸易发展历程及空间格局、进出口产品格局进行深入分析。结果显示双方贸易强度不断提升,且贸易互补性增强,同时俄罗斯及中亚出口产品种类明显增加。当前双方贸易格局呈现以下特点:俄罗斯及中亚形成了以资源类初级产品为绝对主导的出口产品结构,中国则以机械设备及纺织服装等为主;中国对其出口贸易格局是边境贸易与地区产业专业化格局叠加的结果,进口贸易格局则受边境贸易及能源需求格局的影响。     

中纬度亚洲现代间冰期气候变化的“西风模式”讨论

中纬度亚洲地区存在主要受季风环流影响的东南部湿润地区(简称季风区)和主要受西风环流控制的内陆干旱区(包括青藏高原北部高寒干旱区,简称西风区)。根据对近年来新发表的气候变化记录证据梳理总结,发现西风区在中—晚全新世气候湿润,与亚洲季风在早—中全新世强盛的格局显著不同。过去千年的西风区中世纪暖期干旱,而小冰期相对湿润,与此相对,万象洞石笋氧同位素记录则显示季风降水在中世纪暖期时整体处于高值,在小冰期处于低值段。在近百年,尤其是近50a,西北干旱区湿度增加,而季风影响范围内的西北东部和华北等地变得更干。不仅如此,在分属西风和季风影响区的青藏高原北部和南部,年代际—百年尺度上降水变化也表现出反相位关系。据此我们提出,亚洲中部西风带控制区在现代间冰期从数千年到年代际的各个时间尺度上均存在不同于季风区的湿度(降水)变化模式,称之为现代间冰期气候变化的西风模式。     

利用掩星资料分析东亚地区云厚的分布特征

利用2007年1月至2009年1月COSMIC掩星湿空气数据,基于相对湿度廓线出入云层时发生突变反演云边界高度的思想,统计分析了东亚地区云厚的分布特征。结果表明,掩星最低探测高度集中在3km以下,主要影响部分中云和低云云厚的反演。云发生概率沿纬度和经度方向呈现不同的分布特征,各类云概率随高度也有不同的变化规律。东亚地区所有云的平均厚度为1.78km,其中单层云和顶层云分布相似,双层云与其他云层的地理差异不大,单层云在春秋季分布相对均匀,而在夏冬季差异较大。夏季和冬季顶层云云顶高与云厚的二维频率分布各异,主要在于夏季有更多云体较厚且位于对流层上部的高云存在。     

中国暴雨理论的发展历程与重要进展

利用中国气象局所提供的逐小时的站点降水资料与欧洲中期天气预报中心所提供的逐小时、0.25^o（纬度）×0.25^o（经度）的ERA5再分析数据,重点研究了产生郑州极端小时降水的关键天气系统,并对高空急流与副急流进行了动能收支诊断,研究发现：2021年“21·7”河南特大暴雨呈现出显著的阶段性特征,在郑州极端小时降水出现的时段内,强降水主要出现在河南北部的山区及山区的迎风坡周边,受地形影响显著。位于河南上空,对流层高层的高压脊、对流层中层的低压倒槽以及对流层低层的水平切变线与中尺度对流涡旋是引发郑州极端小时降水的关键天气系统。处于南亚高压东北部的高空急流与副急流通过引发强冷平流使得位于陕西上空的对流层高层短波槽快速发展,该槽的斜压发展使得其槽前的暖平流显著增强,从而导致河南上空对流层高层的高压脊迅速发展并维持强高空辐散条件,这为郑州极端小时降水的出现提供了极为有利的背景环流条件。南亚高压东北部的高空急流与副急流呈现出显著的水平分布不均特征,其中,风速增强趋势与冷平流强度均在上层急流分岔点（1区）达到极大值,这为陕西上空对流层高层短波槽的快速增强提供了最有利的条件。动能收支表明,南亚高压东北部偏西风的水平动能输送是本区域内高空急流与副急流发展/维持的最有利因子,其动能主要来源于南亚高压北部边缘的高空急流区;在此阶段内,气压梯度力主要做负功,是最不利于高空急流与副急流发展/维持的因子。     

Inland capture fisheries in the Mekong and their place and potential within food-led regional development

The inland capture fisheries of the Mekong represent critical sources of nutrition in rural diets in a region that faces endemic food and nutritional deficits. However within regional development debates that prioritize utilising the waters of the Mekong to generate electricity, capture fisheries are often presented as ultimately doomed, and therefore as an unfortunate, but necessary trade-off for hydropower. At the heart of these debates, lie contested definitions of development. The notion that fisheries could or should be traded-off for some other form of development exemplifies this tension.This paper draws on anthropological approaches to policy analysis based on discourse and narratives. We begin by placing the conventional wisdom regarding the place of fisheries in regional development under closer scrutiny. We then explore the potential for a counter narrative based around food and food sovereignty, in which fisheries and fishers are drivers, rather than costs of development. We argue that fisheries provide a range of livelihood and developmental values that cannot be replaced and that their management continues to hold potential for strengthening independence and self-reliance. In doing so, we build on empirical evidence from the Lao PDR, a country with a rich capture fishery but also endemic food crises, and also a national policy commitment to both poverty reduction and extensive large-scale hydropower development. As such, this paper attempts to reframe the debate on development in the Mekong. The paper has wider significance for considering how a broader focus on food and food producers can generate alternative development pathways.     

亚洲MAGSAT卫星磁异常图

使用２０多万个ＭＡＧＳＡＴ卫星磁测数据,编绘亚洲卫星标量（△Ｆ）和矢量（△Ｘ,△ｙ,△Ｚ）磁异常图（２０°ｓ－６０°Ｎ,５０°Ｅ－１６０°Ｅ）．为了提取岩石层卫星磁异常,首先对ＭＡＧＳＡＴ卫星数据进行了筛选,然后进行主磁场、磁层场、电离层场和感应场改正,并消除虚假测点．将卫星数据分成黎明组、黄昏组和联合组,分别绘制相应的卫星磁异常图．根据１°×１°的网点值,用计算机编绘亚洲卫星磁异常图．初步分析了卫星磁异常与大地构造的关系．     

Heating status of the Tibetan Plateau from April to June and rainfall and atmospheric circulation anomaly over East Asia in midsummer

Based on the 1958-1999 monthly averaged reanalysis data of the National Center for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) and the rainfall data of 160 Chinese surface stations, the relationship between rainfall and the atmospheric circulation anomaly over East Asia (EA) in July and the sensible heating (SH) over the Tibetan Plateau (TP) from April to June (AMJ) is investigated by using the rotational experimental orthogonal function (REOF) method. The results show that the TP is an isolated heating source in this period. The lagged correlation analysis between the first rotational principal component (RPC) of SH over the TP in May and rainfall of EA in July demonstrates that strong SH over the TP before July leads to a positive rainfall anomaly over the TP, the valley between the Yangtze River and Huaihe River, and the regions south and southeast of the TP, and the Sichuan Basin and Yunnan-Guizhou Plateau, but less rainfall anomaly over the regions north, northeas