ENSO事件指数与指标研究

根据 1 951～ 1 996年完整可靠的海面温度 ( SST)和南方涛动指数 ( SOI)资料 ,以中、东太平洋 SST异常变化为指标 ,定义了 ENSO事件 ,并在此基础上提出了以 ENSO事件过程海温距平累积值为指标的强度指数。此外 ,还定义了 ENSO事件的海 -气综合强度指数 ,并对 ENSO事件的长度、强度及爆发类型等进行了分类。     

大兴安岭气候干湿变化及对森林火灾的影响

明确气候变化背景下大兴安岭林区气候干湿状况特征,揭示其对森林火灾的影响,可为该区域森林火灾管理和森林资源保护提供科学依据。基于大兴安岭林区1974—2016年标准化降水指数（SPI）,采用统计分析和对比分析方法,系统研究不同干湿情景对森林火灾发生次数及过火面积的影响,并讨论不同等级干旱对其影响的异同性。结果表明:1974—2016年,年、季尺度上大兴安岭林区气候均呈湿润化趋势。森林火灾发生次数多（少）和过火面积大（小）与气候的干湿状况（等级）基本一致,但森林火灾的发生次数与气候干湿状况相关更为密切。年尺度上,SPI与火灾次数呈负相关,与过火面积的自然对数则呈较弱的负相关;季尺度上,各季节SPI与对应的林火次数和过火面积自然对数均呈显著的负相关,但与过火面积的相关程度差异较大,以春季相关最为显著,秋季次之,夏季则相对较弱;不同季节SPI与年林火次数和过火面积自然对数呈负相关,前一年冬季SPI对当年火灾次数的贡献最大。可见,气候干湿状况对森林火灾的影响存在明显的滞后效应。SPI不仅能较好地反映区域气候的干湿状况,亦能较好地指示森林火灾发生的可能性及发生火灾的过火面积的相对变化情况,可为森林火灾预测和管理提供科学依据。     

区域气候模拟中多种对流参数化方案的比较研究

利用区域气候模式RegCM2,选择Betts-Miller、Kuo-Anthes和Grell3种积云对流参数化方案,进行了1991年和1994年5～7月2个个例的东亚季风区区域气候模拟试验,重点分析比较了3种参数化方案对降水总量分布、主要降水时段、雨带南北变动和基本气象要素场的模拟能力,并相对实测降水和基本要素的观测分析进行了统计检验.通过对比,发现Betts方案的模拟能力明显优于其他两种方案.     

地下水污染风险评价的迭置指数法研究综述

目前,我国大部分城市采用地下水作为饮用水源,而地下水污染状况日益严重,地下水污染风险评价作为管理者制定污染防治方案的一种手段,显得尤为重要。地下水污染风险评价虽然已经有一定范围的应用,但对其概念并没有统一的定义,因此,在总结国内外地下水污染风险评价研究进展的基础上,提出地下水污染风险的定义,并重点讨论迭置指数法在地下水污染风险评价中的应用,并在此基础上提出存在的问题及建议。     

Source Strata of Gold in Western Guangdong—Their Identification and Significance in Gold Mineralization

Strata of different geological periods extensively outcrop in western Guang-dong Province, but most gold deposits are restricted to the Middle-Late Proterozoic Yunkai Group and the Cambrian Bacun Group,showing obvious strata-boun character-istics .Gold abundance and trace element geochemistry of the Yunkai and Bacun Groups are compared with those of the Ordovician and Silurian strta.The Yunkai Group is considered to be the source strata for gold mineralization in the region.     

The vertical mixing induced by winds and tides over the Yellow Sea in summer: a numerical study in 2012

Ocean Dynamics - In the Yellow Sea (YS), besides the energetic tidal forcing, winds also induce strong vertical mixing, especially in the summer season when the thermocline is well developed. The...     

Groundwater pollution containing ammonium,iron and manganese in a riverbank filtration system: Effects of dynamic geochemical conditions and microbial responses

Bench-scale experiments were conducted to investigate the effect of hydraulic loadings and influent concentration on the migration and biotransformation behaviour of three groundwater pollutants: ammonium (NH₄⁺), iron (Fe²⁺) and manganese (Mn²⁺). Columns packed with aquifer media collected from a riverbank filtration (RBF) site in Harbin City, NE China were introduced synthetic groundwater (SGW) or real groundwater (RGW) were at two different constant flow rates and initial contaminant concentrations to determine the impact of system conditions on the fate of the target pollutants biotransformation. The results showed that the biotransformation rate of Fe²⁺ Mn²⁺ and NH₄⁺ decreased by 8%, 39% and 15% under high flow rate (50 L d⁻¹) compared to low flow rate (25 L d⁻¹), which was consistent with the residence-time effect. While the biotransformation rate of Fe²⁺ Mn²⁺ and NH₄⁺ decreased by 7%, 14% and 9% under high influent concentration comparing with original groundwater. The 16S rRNA analysis of the aquifer media at different depths after experiments completion demonstrated that the relative abundance of major functional microbes iron-oxidizing bacteria and manganese-oxidizing bacteria under higher flow rate and higher influent concentration decreased 13%, 14% and 25%, 24%, respectively, whereas the ammonium-oxidizing bacteria and nitrite-oxidizing bacteria exhibited minimal change, compared to the lower flow rate. Above all results indicated that both high flow rate and high concentration inhibit the biotransformation of NH₄⁺, Fe²⁺ and Mn²⁺. The biotransformation of Fe²⁺ and Mn²⁺ occurs primarily in the 0–40 cm and 20–60 cm depth intervals, respectively, whereas the NH₄⁺ biotransformation appears to occur relatively uniformly throughout the whole 110 cm column. The biotransformation kinetics of NH₄⁺ in RGW and SGW, Mn²⁺ in RGW at different depths accords with the first order kinetics model, while Fe²⁺ in RGW and SGW, Mn²⁺ in SGW presented more complicated biotransformation process. The results should improve understanding of the transport and fate of common groundwater pollutants in RBF and other groundwater recharge environments.     

包头市2011年春季TSP和PM10的污染特征分析

利用包头市2011年春季TSP和PM10的逐时监测数据,对二者的浓度变化及二者之间的相关性进行分析,结果表明：包头市2011年春季空气中颗粒物污染较重,沙尘天气是影响环境质量并造成大气污染的一个主要来源。在TSP含量中,PM10占主要地位,但仍有其他颗粒成分影响其总体组成。TSP和PM10呈线性相关,在沙尘灭气过程中,二者相关性更为显著。     

雨雪天气对内蒙古交通影响服务评估

文章对2012年3月21-23日的一次降水、降温和大风过程,从500hPa高度场形势图和700hPa高度场图、700hPa流场图和850hPa温度场图对天气形势进行了分析,得出预报结论:受冷暖空气共同影响,我区大部地区将出现雨夹雪天气,其中鄂尔多斯市东部、包头市南部、呼和浩特市、乌兰察布市南部、锡林郭勒盟西南部有小到中雨夹雪或雪,个别地区偏大,呼伦贝尔市、兴安盟有小雪,锡林郭勒盟以东地区4、5级偏西风转5、6级西北风,气温下降6℃左右,锡林郭勒盟以西地区4级西南风转4、5级西北风,气温下降4～6℃.对我区境内所有高速公路、铁路沿线以及在建高速公路产生的影响及服务效益进行了评估;对如何提高气象服务提出了一些良好建议.     

Metadata Harvesting and Registration in a Geospatial Sensor Web Registry

A Sensor Web registry acts as a broker in a service‐oriented environment to publish and discover Sensor Web resources (e.g. sensors, sensor services, observations, and alerts). The Catalogue Service for the Web (CSW) developed by the Open Geospatial Consortium (OGC) defines a standard interface and protocol for publishing and discovering geospatial resources. This article adopts the CSW for the development of a Sensor Web registry. Metadata for Sensor Web resources are registered into the catalogue information model – the ebXML Registry Information Model (ebRIM). In the Sensor Web environment, sensor observations can be available in real‐time or near‐real‐time, and thus metadata registered in CSW need to be updated frequently. This article proposes an incremental harvesting approach, which can harvest the updated metadata efficiently. A prototypical implementation is provided to demonstrate the applicability of the approach.