Variability of soil moisture and its relationship with surface albedo and soil thermal parameters over the Loess Plateau

Data from July 2006 to June 2008 observed at SACOL(Semi-Arid Climate and Environment Observatory of Lanzhou University,35.946°N,104.137°E,elev.1961 m),a semi-arid site in Northwest China,are used to study seasonal variability of soil moisture,along with surface albedo and other soil thermal parameters, such as heat capacity,thermal conductivity and thermal diffusivity,and their relationships to soil moisture content.The results indicate that surface albedo decreases with increases in soil moisture content,s...     

Progress in Semi-arid Climate Change Studies in China

This article reviews recent progress in semi-arid climate change research in China.Results indicate that the areas of semiarid regions have increased rapidly during recent years in China,with an increase of 33%during 1994-2008 compared to 1948-62.Studies have found that the expansion rate of semi-arid areas over China is nearly 10 times higher than that of arid and sub-humid areas,and is mainly transformed from sub-humid/humid regions.Meanwhile,the greatest warming during the past 100 years has been observed over semi-arid regions in China,and mainly induced by radiatively forced processes.The intensity of the regional temperature response over semi-arid regions has been amplified by land-atmosphere interactions and human activities.The decadal climate variation in semi-arid regions is modulated by oceanic oscillations,which induce land-sea and north-south thermal contrasts and affect the intensities of westerlies,planetary waves and blocking frequencies.In addition,the drier climates in semi-arid regions across China are also associated with the weakened East Asian summer monsoon in recent years.Moreover,dust aerosols in semi-arid regions may have altered precipitation by affecting the local energy and hydrological cycles.Finally,semi-arid regions in China are projected to continuously expand in the 21st century,which will increase the risk of desertification in the near future.     

江苏句容早三叠世鱼类化石之发现及其意义

记述了江苏句容下三叠统青龙组下三叠统青龙组下部地层中发现的软骨硬鳞鱼类一新种－江苏裂齿鱼和半椎鱼类一新种－句容鳞齿鱼化石，并讨论了其分类特征、生存环境及化石埋藏状况。     

突出小地震活动事件作为中强震短临预报判据的研究

对新疆1970年以来突出小震活动事件进行了统计分析,给出突出小地震活动事件与5级以上中强震的对应关系,提出以突出小地震活动事件中小地震发生的时间间隔和频度预报中强震的短期判据。     

Preliminary studies on the diel vertical migration of Clanus sinicus (nauplius-adult) larvae atevery stage in the North Huanghai Sea

There have been a lot of papers on the diel vertical migration of marine copepoda published at home and abroad. But so far, no report on the diel vertical migration of the larvae of Clanus sinicus has been seen. The present paper discusses this problem and the result obtained will provide useful reference for further researches on this subject. Moreover, exploring the law of diel vertical migration of the secondary productivity in the ocean will help the development of marieulture and fishing in a scientific way.     

Effect of lateral boundary scheme on the simulation of tropical cyclone track in regional climate model RegCM3

The effect of the lateral boundary scheme in regional climate model (RCM) on the track simulation of tropical cyclone (TC) was investigated using RegCM3, for the case of Winnie (1997), which formed in the Western Pacific and landed on China in August 1997. The results show that there is an inevitable simulation error in the track of Winnie, and the narrower buffer zone size (BZS) will make a great error. However, it was demonstrated that a much broader BZS does not allow a better track simulation of Winnie, and the optimal BZS does not reduce the track error substantially. Moreover, the configuration scheme of nudging parameters plays an important role in the track simulation, and different nudging parameter configuration scheme could make the root mean square errors (RMSEs) of simulated track by more than two times. Nevertheless, the optimal configuration scheme can reduce the track error effectively by maintaining the equilibrium between the two additional nudging terms in the prognostic equations in the buffer zone, whereas both the strong nudging scheme and the weak nudging scheme distort the track simulation of the Winnie. It is also found that the simulated weaker west Pacific subtropical high (WPSH), which leads to the turning of the TC ahead of time, is the reason for the track simulation error. A possible approach for reducing track simulation error of TCs is also discussed.     

耦合模式在局地辐射雾三维数值模拟研究中的应用

本文利用中尺度数值模式MM5与三维辐射雾模式相耦合,分别对重庆和长沙地区的一次冬季辐射雾过程进行了模拟研究。结果表明,中尺度数值模式与三维辐射雾模式的单向耦合可以较好地模拟出雾的生消演变过程,以及雾的浓度、地理分布特征、形成和维持。由此可以说,利用耦合模式开展雾的预报是可行的。     

改进的SCS模型在黑龙江省中小流域径流模拟中的应用

针对黑龙江省中小流域特征,以烟筒山、铁力、岔林河桥、中和4个流域为研究区,引入初损比例m和系统偏差系数k两个参数对SCS模型进行改进,探讨改进的SCS模型在模拟黑龙江中小流域降雨-径流的可行性。结果表明:改进的SCS模型模拟的效率系数均为0.80以上,可以有效的模拟黑龙江省中小流域的降雨-径流。     

广西区域极端特大暴雨成因个例分析

利用常规观测资料、FY-2E卫星观测资料、雷达探测资料以及自动站雨量资料等,对2010年6月28日广西极端特大暴雨过程进行分析;结果表明：①暴雨灾害具有区域小、降雨时段集中、过程雨量大、短历时降雨强及引发次生灾害特别重等特点;②亚欧中高纬度500 hPa呈两脊一槽型、200 hPa南亚高压脊线贯穿广西上空及西南季风活跃是暴雨的环流背景;高空低涡、地面干线是主要天气系统配置,属低涡暴雨型;③强不稳定能量及层结的存在、850 hPa以下低层辐合、700 hPa附近明显涡旋、整层大气上升运动、850 hPa以下层高湿及水汽强烈辐合是主要物理量特征;④中尺度低压、低涡及气流辐合等是中尺度对流触发条件.FY-2E红外云图上对流云团生成、合并对强降雨有重要指示意义,暴雨发生在云团合并发展阶段,FY-2E的TBB值小于200 K可以作为短历时强降雨的指标.低质心雷达回波产生的列车效应和地形作用是造成强降雨的重要因素,低层辐合、高层辐散导致的强烈上升运动,有利于强对流的发展与维持.