一种从经纬度网格资料获得正方形网格资料的插值方案

本文提出了一种把经纬度网格点上的气象要素值转化到正方形网格点上的多项式插值方案。对插值方案作了稳定性讨论和定量及定性分析。结果表明,这种插值方案方便可行,而且有广泛适用性。     

Geo-effectiveness of solar wind extremes

Examples of extreme events of solar wind and their effect on geomagnetic conditions are discussed here. It is found that there are two regimes of high speed solar wind streams with a threshold of ∼ 850 km s^-1. Geomagnetic activity enhancement rate (GAER) is defined as an average increase in Ap value per unit average increase in the peak solar wind velocity (Vp) during the stream. GAER was found to be different in the two regimes of high speed streams with +ve and-ve IMF. GAER is 0.73 and 0.53 for solar wind streams with +ve and -ve IMF respectively for the extremely high speed streams (< 850 km s^-1). This indicates that streams above the threshold speed with +ve IMF are 1.4 times more effective in enhancing geomagnetic activity than those with -ve IMF. However, the high speed streams below the threshold with -ve IMF are 1.1 times more effective in enhancing geomagnetic activity than those with +ve IMF. The violent solar activity period (October–November 2003) of cycle 23 presents a very special case during which many severe and strong effects were seen in the environment of the Earth and other planets; however, the z-component of IMF (Bz) is mostly positive during this period. The most severe geomagnetic storm of this cycle occurred when Bz was positive.     

Multivariate analysis of heavy metal contents of sediments from Gumusler creek, Nigde, Turkey

In this study, heavy metal contents of samples from Gumusler creek in Turkey were studied and the metal contamination characteristics were investigated. In this respect, considering the pollutant sites in the area, systematic sediment samples were collected in a zone starting from the manifestation part of the water to the entrance of the Karasu creek in Gumusler town. Samples were taken from lower section of the river bed at 30 stations along Gumusler creek, 13 km in length and their heavy metal contents were analyzed with XRF Spectrometer. Correlation coefficients, element coefitic coefficient correlation, dendogram hierarchical cluster, model summary and Annova analysis statistical methods were applied to data. Strong positive correlations were determined for some elements which are believed to have possibly the same origin. In addition, mineralizations in the area are thought to cause variation in metal contents. Results of chemical analysis show that soil limit values and clark values were exceeded. The heavy metal accumulation in the creek is believed to be derived from non-operated Sb-Hg-W and Fe quarries.     

Heavy metals in sediments of the Tecate River, Mexico

Ten sites along the Tecate River, Mexico were sampled to evaluate the cadmium, lead, nickel and chromium concentrations in sediments. The result shows contamination for cadmium in most of the sites, where two sites were class 4 (polluted to strongly polluted) according to geoaccumulation index proposed by Muller. Two sites were found polluted for all the heavy metals analyzed (Cr, Cd, Pb and Ni), indicating the effect of anthropogenic activities. A correlation between Ni and Cd concentration had been found indicating a common source. These metals are usually used in electroplating industry. The results of this study can be used for decision makers to prioritize measures to control the pollution for these metals.     

Anthropogenic influence on trace element geochemistry of healing mud (peloid) from Makirina Cove (Croatia)

Due to their balneotherapeutic features, the organic-rich sediments in Makirina Cove are an important source of healing mud. An environmental geochemistry approach using normalization techniques was applied to evaluate the anthropogenic contribution of trace metals to sediments used as healing mud. Sediment geochemistry was found to be associated with land-use change and storm events, as well as with proximity of a road with heavy traffic in the summer months. Local valley topography preferentially channels lithogenic and pollutant transport to the cove. Concentrations and distribution of trace metals indicate lithogenic (Ni, Cr, Co) and anthropogenic (Pb, Cu, Zn and Se) contributions to the sediments. The calculation of enrichment factors indicates a moderate (EFs between 2–3.5) input of anthropogenic Cu and Pb in surficial sediments to a depth of 10 cm. Patients using the Makirina Cove sediments as healing mud could be to some extent exposed to enhanced uptake of metals from anthropogenic sources via dermal contact.     

An operational multiscale system for hazards prediction, mapping, and response

By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3) have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number of different situations.     

松花江哈尔滨段河床冲积物与沙尘天气关系的讨论

笔者重点分析了哈尔滨河床冲积物的粒度组成,结合沙尘沉降物的粒度组成,论述了裸露河床冲积物对沙尘天气的影响。河床冲积物及沙尘沉降物粒度分析结果显示,裸露河床冲积物粒径大于63μm的颗粒占84%以上,而小于63μm粒径的颗粒很少,小于10μm的颗粒微乎其微;沙尘沉降物中小于63μm的粉粘颗粒含量在90%以上。对河床冲积物而言,无论是砂级别的粗颗粒物质还是粉粘级别的细颗粒物质都与沙尘沉降物的粒度无相关性,对沙尘暴物质组成没有影响或影响很小。受砂级别的粗颗粒物质扬起高度和搬运距离的限制,沙尘暴发生时,裸露河床中的冲积物颗粒不会被远距离搬运而影响到整个哈尔滨地区,真正影响整个哈尔滨地区的沙尘物质是小于63μm的粉砂级别的颗粒,特别是小于10μm的粉尘。笔者认为对哈尔滨沙尘天气产生重大影响的是含有大量细颗粒物质的城市地表土和建筑土等,这些地域是防止沙尘天气的重点治理区域。     

气象卫星用于近海污染监测及赤潮预报方法探索

近年来，由于工农业和沿海养殖业的发展，我国近海污染逐年加重，赤潮发生频次增加。因此，监测近海污染和赤潮发生预报方法研究势在必行。本文用ＮＯＡＡ／ＡＶＨＲＲ数据，分析近海水域污染状况，并探索赤潮发生的预报方法。     

一个具有下垫面温度耦合的大气环流的统计—动力模式

本文从动力学定律出发,推导了一个线性的、具有下垫面温度耦合的大气环流的统计—动力模式,并用该模式对500hPa高度场及1000hPa温度场作1～30天的平均预报试验。模式的预报结果大大优于惯性预报,但耦合与不耦合的结果差别不大。     

前颌间银鱼资源变动原因的初步探讨

于1985—1988年对前额间银鱼生物学特性、资源变动状况及其原因进行了现场和社会调查。调查表明,前颌间银鱼资源变动的原因是南、西区和吴淞口三大污染源对其生态环境严重污染;同时还有多年持续过捕超过其再增殖能力。为此,提出治理污染,恢复前颌间银鱼的生活环境及保护繁殖亲体的对策和建议。