“3S技术”集成在地震灾害调查与研究中的应用初探

遥感(RS)、全球定位系统(GPS)和地理信息系统(GIS)技术在自身进一步发展的同时,正日益朝集成化方向迈进,形成所谓“3S技术”集成。“3S技术”集成,为地震灾害调查和研究提供了新的、极具潜力的技术支持。本文简要分析了“3S技术”在震害调查与研究中的应用现状,并着重从“3S技术”集成的角度,探讨它在未来震害调查与研究中的应用模式及实施方案问题。     

重磁位场曲化平计算方法的改进

本文分析了“曲面转换系统”计算方法中存在的问题,提出了改进方法,可充分发挥系统功能。     

云南镇沅金矿煌斑岩矿化过程中元素活动规律

广泛分布于云南镇流金矿、与金矿化在时间上、空间上密切共生的煌斑岩普遍遭受不同程度的蚀变,部分经历了矿化作用,根据岩石的蚀变相对强弱及是否矿化,本区煌斑岩可分成新鲜（弱蚀变）、蚀变、矿化三种。在用质量平衡方程计算了区内煌斑岩蚀变过程中元素活动规律的基础上,本文采用该方法计算了煌斑岩矿化过程中元素的活动规律。结果表明,引起本区煌斑岩矿化的流体为一种富含K2O、CaO、CO2、F、Cl、S、As、Sb、An、Ag等组分的流体;成矿元素（Au）的来源及稳定同位素显示这种流体具有多源性。     

1992年6月26日Hα耀斑后环的不均匀性和物质运动的可能解释

本文利用电流不稳定性线性理论讨论了１９９２年６月２５日至２６日耀斑后环中出现不均匀“结”状结构（“ｋｎｏｔ”或“ｂｌｏｂ”）的可能性,并且在同时考虑重力、磁力和环顶物质下落初速的情况下,理论计算了１９９２年６月２６日Ｈα耀斑后环物质运动的规律。理论计算与观测求得的视向速度随高度分布的曲线基本符合。     

CMIP6模式对中国东部地区水循环的模拟能力评估

本文基于观测和再分析资料,采用Brubaker二元模型评估了第六次国际耦合模式比较计划（CMIP6）中19个模式对中国东部季风区气候态水循环过程的模拟能力,并分析了模拟误差来源。结果表明,CMIP6模式集合平均（MME）能够合理再现观测降水和蒸发的年平均气候态空间分布及年循环特征,与观测值的空间相关系数分别为0.92和0.87。较之观测,MME高估了华北地区降水（0.55 mm d?1）,低估了华南沿海地区降水（?0.3 mm d?1）。所有CMIP6模式均高估蒸发强度（偏差0.03～0.98 mm d?1）,使得模拟的降水与蒸发之差偏少。模式整体能够模拟出我国东部季风区降水再循环率及不同边界水汽来源的贡献率,但低估了由南边界进入季风区的水汽贡献,导致东亚季风区偏干。通过分析模式对影响水汽通量的两个气象要素（风速和大气比湿）的模拟能力,发现研究区南边界的风速大小决定了模式间水汽输送差异。南边界风速越大的模式,由南边界进入的水汽通量越大,模式模拟的降水越多。西北太平洋辐合带的东西位置是影响南边界南风速的重要系统之一,辐合带位置偏东的模式模拟的南风强度较弱,使得水汽输送偏弱、降水偏少;反之,南边界水汽输送偏强、降水偏多。本文通过评估最新一代CMIP6模式在东亚水循环方面的模拟性能,指出了当前气候模式在模拟西太平洋辐合带位置方面存在的偏差及其对东亚水循环的影响。     

Parameterizations of different hydrometeor spectral relative dispersion in the convective clouds

Spectral relative dispersion of different hydrometeors is vital to accurately describe sedimentation. Here, the Weather Research and Forecasting model with spectral bin microphysics is used to simulate convective clouds in Shouxian of Anhui province in China to study the spectral relative dispersion of different hydrometeors. Firstly, regardless of clean or polluted conditions, the relative dispersion of ice crystal spectra and its volume-mean diameter are negatively correlated, while the relative dispersion of other hydrometeor spectra is positively related to their respective volume-mean diameter. The correlations for cloud droplets and raindrops are affected by the process of collision–coalescence; the correlations for ice crystals, graupel particles, and snow particles could be affected by the deposition, riming, and aggregation processes, respectively. Secondly, relative dispersion parameterizations are developed based on a comprehensive consideration of the relationships between the relative dispersion and volume-mean diameter under both polluted and clean conditions. Finally, the relative dispersion parameterizations are applied to terminal velocity parameterizations. The results show that for cloud droplets, ice crystals, graupel particles, and snow particles, assuming the shape parameter in the Gamma distribution is equal to 0 underestimates the shape parameter and overestimates the relative dispersion; and for raindrops, assuming the shape parameter is equal to 0 is close to the relative dispersion parameterizations. The most appropriate constant shape parameters are recommended for different hydrometeors. The relative dispersion parameterizations developed here shed new light for further optimizing the terminal velocity parameterizations in models.摘要离散度的诊断对模式中沉降过程的准确描述至关重要. 本文利用WRF模式结合谱分档方案模拟安徽寿县地区的对流云, 研究不同水成物的离散度. 首先, 无论在清洁还是污染条件下, 除冰晶谱的离散度与体积平均直径间呈现负相关关系外, 云滴, 雨滴, 霰粒子与雪粒子谱离散度与体积平均直径呈现正相关关系; 云滴和雨滴受碰并过程影响, 冰晶, 霰粒子和雪粒子分别受凝华过程, 淞附过程和聚并增长影响. 其次, 综合考虑污染与清洁条件下离散度和体积平均直径之间的相关关系, 建立了离散度的参数化方案. 最后, 把该离散度方案应用到下落末速度的参数化方案中, 结果表明, 对于云滴, 冰晶, 霰粒子和雪粒子, 在Gamma分布中假设谱形参数等于0会低估谱形参数而高估离散度. 对于雨滴而言, 假设谱形参数等于0与参数化方案结果接近. 针对不同的水成物, 给出了最合适的谱形参数定值. 本文发展的离散度方案为进一步优化模式中下落末速度参数化方案提供参考.     

Speculations on the Thermal and Tectonic History of the Earth

Summary. The connection between the Earth's thermal history and convection in the mantle is exploited to elucidate the early evolution of the Earth. It appears probable that convection extending over almost all of the mantle has dominated vertical heat transport throughout the whole of the Earth's history. Only in boundary layers at the surface and at a depth of 650–700 km is conduction likely to be important. The resulting evolution appears to be consistent with geological observations on early Precambrian rocks.
Various arguments are put forward in favour of two horizontal scales of convective flow in the mantle at depths less than 650 km. The large scale flow is related to the motion of major plates, and must be ordered over distances of more than 5000 km. Its evolution and energetics are discussed and there are no obvious problems in maintaining the proposed convective motions. Small scale flow with an extent of the order of 500 km appears necessary both to explain the heat flow through older parts of the Earth's surface and to reconcile the geophysical observations with the results of numerical experiments. Though the existence of the small scale flow is at present speculative, various tests of its presence are proposed.