东亚地区云和地表反照率对硫酸盐直接辐射强迫的影响

文中利用区域气候模式深入探讨了东亚地区云及地表反照率对硫酸盐直接辐射强迫的影响 ,同时定量估算了东亚地区云区气溶胶的直接辐射强迫 ,讨论了硫酸盐对地表和大气短波辐射平衡产生的不同影响。研究表明 :云对气溶胶的直接辐射强迫具有很强的减弱作用 ,这种减弱作用不仅取决于云覆盖份数 ,而且取决于云的光学厚度。就区域平均而言 ,文中模拟的东亚地区气溶胶直接辐射强迫为 - 0 .0 97W /m2 ,占总直接辐射强迫的 10 .4%左右。表明云对硫酸盐直接辐射具有很强的减弱作用 ,在估算其总的直接辐射强迫时 ,云区的贡献不可忽视。较高的地表反照率会减弱硫酸盐的直接辐射强迫 ,而较低地表反照率则会增加硫酸盐的辐射强迫。硫酸盐气溶胶对大气辐射平衡影响非常小 ,但对地表辐射平衡产生重要影响 ,影响程度与大气几乎一致。     

Clarification of nonlinear retardation factors for colloid-enhanced transport in porous media

There have been a couple of contaminant retardation factors reported for the three-phase (aqueous, solid, and colloid) groundwater system. However, the retardation factor has often been presented by itself and not incorporated into the relevant transport equation, particularly when derived from the mass fraction approach. This may cause a misunderstanding of the retardation factor especially for the systems where multi-phases exist due to the presence of colloids and/or nonlinear sorption processes are involved. It is, therefore, necessary to clarify the form of the nonlinear retardation factor along with the relevant transport equation in the multi-phase system. Alternative forms of the retardation factor and relevant transport equation for specific conditions are presented in various combinations of the nonlinearity of involved sorption mechanisms. The retardation factors for specific conditions are compared with the ones available in the literature. The results indicate that more caution should be given in applying the retardation factor in order to explore contaminant transport in the multi-phase system where any nonlinear sorption is involved. Finally, presentation of the retardation factor along with the relevant transport equation in this study would help prevent possible misuse of the retardation factor in investigating contaminant transport in the multi-phase system.     

中川地区一次负地闪的起始过程研究

利用ＧＰＳ同步的多点慢天线电场变化仪在甘肃中川地雷暴过程中测量得到的资料,对一次负地闪的起始过程进行了分析。发现地闪产和在击发之前常有持续１７０－３００ｍｓ的去２内放电过程发生,它可有数据不等的Ｋ变化组成。     

Geo-environmental parametric 3D models of SARS-CoV-2 virus circulation in hospital ventilation systems

The novel coronavirus, SARS-CoV-2, has the potential to cause natural ventilation systems in hospital environments to be rendered inadequate, not only for workers but also for people who transit through these environments even for a limited duration. Studies in of the fields of geosciences and engineering, when combined with appropriate technologies, allow for the possibility of reducing the impacts of the SARS-CoV-2 virus in the environment, including those of hospitals which are critical centers for healthcare. In this work, we build parametric 3D models to assess the possible circulation of the SARS-CoV-2 virus in the natural ventilation system of a hospital built to care infected patients during the COVID-19 pandemic. Building Information Modeling (BIM) was performed, generating 3D models of hospital environments utilizing Revit software for Autodesk CFD 2021. The evaluation considered dimensional analyses of 0°, 45°, 90° and 180°. The analysis of natural ventilation patterns on both internal and external surfaces and the distribution of windows in relation to the displacement dynamics of the SARS-CoV-2 virus through the air were considered. The results showed that in the external area of the hospital, the wind speed reached velocities up to 2.1 m/s when entering the building through open windows. In contact with the furniture, this value decreased to 0.78 m/s. In some internal isolation wards that house patients with COVID-19, areas that should be equipped with negative room pressure, air velocity was null. Our study provides insights into the possibility of SARS-CoV-2 contamination in internal hospital environments as well as external areas surrounding hospitals, both of which encounter high pedestrian traffic in cities worldwide.     

卫星云图和数值预报产品及雷达资料相结合作短时预报

在短期和短时天气预报工作中，本文通过对卫生云图的定量分析和研究，结合天气形势、数值预报产品及雷达回波资料，给出了运城市短时降水预报指标，以提高云图在短时预报中的可用性。     

利用探空资料计算云层对辐射的影响

本文对两次江淮流域的梅雨天气过程作了辐射特征分析。着重考虑了云层对太阳辐射和大气长波辐射的影响。计算时假设云层随高度的分布由大气的湿度决定,方案考虑了大气中云层随高度的分布,所得结果能反映实际大气中各种云的辐射特征。     

A comparison of geochemical information obtained from two fluvial bed sediment fractions

 A total of 121 bed sediment samples were collected from a 5.8-km stretch of Manoa Stream, Hawaii. Samples were physically partitioned into two grain-size fractions, <63 μm and 63–125 μm, acid digested and analyzed by ICP-AES and FAAS. Non-parametric matched-pair statistical testing and correlation analysis were used to assess differences and strengths of association between the two fractions for Al, Ba, Cu, Fe, Mn, Ni, Pb, Ti and Zn. Results indicated statistically significant differences between fractions for all elements except Mn. Concentrations were significantly greater in the <63 μm fraction for Al, Cu, Pb, Ti and Zn, while Ba, Fe and Ni were higher in the 63–125 μm fraction. Though some elements had statistically significant differences between fractions (Al, Ba, Fe and Zn) percentage differences were in the range of analytical precision of the instrument and thus differences were not practically significant. Correlation analysis indicated strong positive associations for all elements between the two fractions (p<0.0001). Three contamination indices indicated similar degrees of pollution for each size fraction for four elements having an anthropogenic signal (Ba, Cu, Pb and Zn). The environmental information obtained from the 63–125 μm fraction was essentially equivalent to that from the <63 μm fraction. In this system it is clear that both bed sediment fractions indicate anthropogenic enrichment of trace metals, especially Pb, and further supports previous research that has found that aquatic sediments are critical median for tracing sources of pollution. Received: 17 August 1998 · Accepted: 30 October 1998     

Military pollution and natural purity: seeing nature and knowing contamination in Vieques, Puerto Rico

Military activities have produced contaminated environments at many sites around the world. This contamination and the associated health risks play a large role in how these places can be redeveloped after military use. In this essay we focus on the island of Vieques, Puerto Rico which was used as a bombing range by the US military for six decades until 2003. We examine the ways different groups of people perceive this formerly militarized landscape and the ways that these perceptions legitimatize certain redevelopment options over others. Through participant observation, semi-structured interviews and an analysis of textual materials we found that many local residents view the island as suffering from severe contamination while the large number of visitors, tourism promoters and North Americans now flocking to the post-militarized Vieques view it quite differently. These perceptions of purity and contamination, affected by different knowledges of the island’s history, have led to differing valuation of the landscape and contentious economic, political, and cultural battles over an island often labeled “natural” despite a history of military use and social exclusion.

东亚地区云垂直结构的CloudSat卫星观测研究

本文利用卫星CloudSat同时结合了与其同轨道的卫星CALIPSO(Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations)2007至2009年3年的观测资料,将东亚地区划分为六个研究区域,着重研究了东亚地区云垂直分布的统计特征.结果表明:东亚地区不同高度的云量之和具有明显的季节变化趋势,夏季最大,春秋次之,冬季最小.海洋上空的单层云量最大值出现在冬季,而在陆地上空则出现在夏季.从云出现概率来看,东亚地区单层云出现的概率在春、夏、秋、冬季节依次为52.2%,48.1%,49.2%和51.9%,而多层(2层和2层以上)云出现的概率在春、夏、秋、冬季节分别为24.2%,31.0%,19.7%,15.8%.云出现的总概率和多层云出现的概率,在六个区域都呈现出夏季最大,冬季最小;对4个季节都呈现出东亚南部比东亚北部大,海洋上空比陆地上空大的特点,表明云出现的总概率的季节变化主要由多层云出现的概率的变化决定.东亚地区云系统中最高层云云顶的高度,在夏季最高,为15.9 km,在冬季最低,为8.2 km;在东亚南部和海洋上空较高,平均为15.1 km;在东亚北部较低,平均为12.1 km,且呈现东亚南北部之间差异较大的特点.东亚地区云系统的云层厚度基本位于1 km到3 km之间,且夏季大,冬季小;对同一季节,不同区域的云层厚度差别较小;当多层云系统中的云层数目增加时,云层的平均厚度减少,且较高层的云层平均厚度大于较低层的.云层间距的概率分布基本呈单峰分布,出现峰值范围的云层间距在1到3 km之间,各区域之间没有明显差别,季节变化也不大.本文的研究为在气候模式中精确描述云的垂直结构提供了有用的参数化依据.     

CloudSat/CALIPSO卫星资料分析云的全球分布及其季节变化特征

全球气候模式（GCM）中云的参数化方案具有不确定性,了解云的时、空变化能为参数化方案提供有效参考。利用搭载在属于A-Train卫星序列的CloudSat和CALIPSO上的94 GHz云廓线雷达（CPR）以及正交极化云-气溶胶激光雷达（CALIOP）联合的2级云分类产品,分析了2007年3月-2010年2月8种云类及三相态的云量地理分布、纬向垂直分布的季节变化特征以及云层分布概率。结果发现,卷云的分布体系与深对流云相似,主要集中在西太平洋暖池、全球各季风区及赤道辐合带,分布格局与气压带、风带季节性移动一致。层云与层积云主要分布在中低纬度非季风区以及中高纬度的洋面上。高积云与高层云的分布形成明显的海陆差异,雨层云与积云的分布形成明显的纬度差异。冰云分布与卷云相似,云高随纬度递增而递减;水云分布与层积云相似,平均分布于2 km高度;混合云集中于高纬度地区及赤道辐合带,中纬度地区随纬度变化集中于海拔0-10 km的弧形带。层状云多以多层云形式出现,积状云多以单、双层云的形式出现,层状云的云重叠现象比积状云更显著。积状和层状云的分布特征与积云和层云降水的分布特征基本一致,验证了不同类型降水的卫星观测结果,同时为气候模式的云量诊断方案提供对比验证的数据。