The mistral and its effect on air pollution transport and vertical mixing

Within the framework of ESCOMPTE, the influence of local wind systems like land–sea/mountain–valley winds on the distribution of air pollutants in the southern part of the Rhône valley and the coastal regions of southern France was investigated. In addition, the influence of the mistral on the long-range transport and vertical mixing of such substances on July 1, 2001 was analyzed. The results of the measurements of this mistral situation show high concentrations of O₃ and NO₂ in the layer just above the PBL at the southern exit of the Rhône valley near Avignon. By measurements from airborne and ground-based platforms and numerical simulations with the “Local Model” (LM) of the German Weather Service (DWD), it is shown that the mistral develops according to the theory conceived by Pettré [J. Atmos. Sci. 39 (1982) 542–554]. The synoptic-scale northerly flow through the Rhône valley is accelerated up to a Froude number (Fr) of 2.1, while the valley widens. Then, near the Mediterranean coast, a hydraulic jump occurs and Fr drops down to values below 1.0. High ozone concentrations of 112 ppb measured above the mistral layer disappear due to enhanced mixing after the flow has passed the hydraulic jump. There is some evidence that the ozone-rich air originates from the source region of greater Paris or upwind. The results confirm that regional wind systems associated with transport of trace gases in the high-grade industrialized Rhône valley can be successfully predicted using data of operational weather forecast models.     

塔里木河下游生态输水对沙漠化逆转的影响

1 IntroductionThe Tarim River (Figure 1), located in the X injiang U ygur A utonom ous Region in N orthw estChina,is the largestinland river in China.The annualaverage precipitation of the Tarim Rivervaries from 17.4 m m to 42.0 m m w hile the annual aver…     

Evaluation of the optimal performance of passenger vehicle by integrated energy-environment-economic modeling

Analysis of multi dimensional interactions of flow of energy in passenger vehicle is a complex task that necessitates development and utilization of analytical tools. Development of analytical tools with high complexity is usually based on conclusions of many concepts and theories from different scientific disciplines. In this approach, Passenger vehicle is supposed to be organized in the form of a firm and appears in the market that oriented towards establishing an effective energy supply system which may be identified as delivering the product (person kilometer or tone kilometer) with minimum operation costs. To this end, an optimization model named power software founded on theory of firm of microeconomics has been developed using technique of mathematical programming. Base on this theory, the car owner tries to minimize the total cost of the system subject to the satisfaction of the required transport services and technological, economical, environmental and institutional constraints. The approach and the application of the model shall be demonstrated with the help of a case study. The result of this study shows the extent of optimal energy usage subject to meeting the required certain urban transport service.     

Early Variscan HP metamorphism in the western Iberian Allochthon—A 390 Ma U–Pb age for the Bragança eclogite (NW Portugal)

HP rocks (eclogites and granulites) occur in the upper unit of the western Iberian allochthonous complexes in Spain and Portugal. This HP metamorphism was considered as Early Variscan or Ordovician in Spain and Precambrian in Portugal. We have dated eclogites retrogressed into granulites in the Bragança massif in NE Portugal by U–Pb on rutile and zircon. The upper intercept of the discordia gives 390±4 Ma that we consider as the age of the HP/HT metamorphism.     

太阳整体行为研究

黑子相对数与黑子群在日面纬度上分布的蝴蝶图表征着太阳长期活动演化的特征 ,本文主要对这二者尤其是后者进行了研究。太阳活动在日面上分布表现为不对称 ,这是近 30年太阳物理研究的主要内容之一。本文对这一领域进行了详细调研 ,发现太阳活动的南北半球分布不对称性的确存在 ,是否存在东西半球分布不对称性目前还没有定论 ,但在日面经度上的分布肯定是不均匀的。本文还利用太阳 2 2周活动极大时期X射线 (Imp≥M1 .0 )耀斑事件进行了统计分析 ,给出了不对称演化特征 ,发现不对称性并不是事件活动剧烈程度的函数。统计分析表现 2 1周太阳活动既不是已往文献中所述的南半球占优 ,也不是北半球占优。本文总结了以往对太阳长期活动特征研究的结论 ,也分析了黑子面积描述的活动周特征 ,发现可用一个二参数函数来描述太阳活动周 ,这个结论对太阳长期活动预报是有用的。本文还详细解剖了蝴蝶图 ,揭示了其所含的物理信息 ,同时将不对称研究引入到这种解剖工作中 ,或是定量再现已有的一些定律 ,一些效应 ,或是揭示一些新的长期活动特征。本文最后对太阳长期活动预报方法和预报结论进行了总结 ,2 1～ 2 3周的预报事例说明前兆因子方法比其它方法要好。本文用Moscow中子监测值对 2 3周作了预报 ,其峰值为 1 51 .1