基于EC模式闪电格点概率预报模型及应用

基于EC（0.25°×0.25°）模式预报资料和闪电定位资料，结合雷暴三要素形成条件，分别从水汽、能量、热力、动力等几个方面挑选预报因子，利用主成分分析方法配料权重系数，并根据海拔高度将四川划分为四川盆地、攀西地区、川西高原3个不同的区域分别建立预报模型，研发了四川省闪电格点概率预报产品。检验结果表明：四川盆地在概率预报值为70%以上时，预报效果较好，TS评分为0.294；攀西地区和川西高原在概率预报值为60%以上时，预报效果较好，TS评分分别为0.302和0.299。     

国家湿地公园河流廊道建设模式与技术研究——以江西修河国家湿地公园为例

在回顾和总结国内外生态廊道、河流廊道研究进展的基础上,以江西修河国家湿地公园为例,在分析江西修河国家湿地公园的主体——修河河流廊道的现状、建设要求和生态功能侧重点的基础上,确定了修河河流廊道的宽度,提出了针对不同功能需要和不同区段的修河河流廊道建设模式,以期为修河河流廊道的建设提供指导和依据,把修河打造成"蓝水绿岸"式的生态河流廊道,并为我国河流廊道型国家湿地公园的建设模式和技术提供指导。     

基于第二类无奇点根数的改进根数

采用经典Kepler根数描述天体的基本运动方程时,若出现近圆或近赤道情况,将导致一系列的不确定性,即奇点问题。由于导致这类数学奇点的原因是基本根数变量的选择不当,因此有针对性地选择无奇点根数可以解决这一问题。在前人提出的改进的第二类无奇点根数的基础上,给出详细的星历计算和轨道计算推导过程。并且通过摄动运动方程形式分析以及数值计算对改进根数进行了验证。     

2009年度大气科学领域项目评审与研究成果分析

1 2009年项目申请、送审与资助情况 2009年地球科学五处共受理各类项目768项(表1),其中,面上项目382项,青年科学基金254项,地区科学基金37项,上述3类项目共673项;"天气与气候系统变化过程与机制"优先发展领域重点项目18项(均为大气学科),"全球变化及其区域响应"优先发展领域重点项目41项(其中大气学科11项);国家杰出青年科学基金24项,海外及港澳学者合作研究基金5项,共计29项;创新研究群体科学基金3项;科学仪器专项基金3项;联合资助基金1项.     

东亚地区陆地植被净初级生产力与夏季气候的模拟

利用中国科学院大气物理研究所(IAP)一个海洋-大气-动态植被耦合模式(GOALS-AVIM),进行了100年模拟积分.基于模拟结果,对东亚地区的植被净初级生产力(NPP)、降水、地面气温和短波辐射的季节变化进行了标准化对比,分析了NPP的时空格局与气候因子(气温、短波辐射和降水)的关系;利用奇异值分解(SVD)对东亚夏季降水场和NPP的关系进行分解.结果表明,夏季东亚地区植被NPP及相关气候因子的时空变化规律明显,耦合模式可以很好地模拟出观测存在的降水及NPP、LAI(叶面积指数)大值区随季节北移南退的形态;由于耦合模式中AVIM的双向特点,模式模拟的NPP与其他物理场的季节变化有很强的对应关系,而且在不同时间和地区,NPP与降水、地面气温、短波辐射表现出不同的对应关系,其中植被NPP时间变化与气温和降水的相关性都较高;从NPP场和降水场夏季逐月标准化距平奇异值分解的空间分布模态来看.NPP与降水在时空场上表现出很强的耦合性,NPP的空间格局与降水存在较好的相关性,不同地理位置的相关性强弱不同,分解出的降水场异常相关模态也再现了东亚夏季降水移动的时空特征,同时东亚雨带随季节变化与NPP的气候变率表现出不同的对应模态.     

一个海陆气耦合模式中大气-植被的年际变化及其相互作用

含有动态植被过程的陆面模式Atmosphere-Vegetation Interaction Model(AVIM)与中国科学院大气物理研究所大气科学与地球流体力学数值模拟国家重点实验室(IAP/LASG)的9层大气环流模式AGCM 及20层的海洋环流模式(OGCM)耦合,建立了一个全球模式(GoALS-AVIM)并进行100年的模拟积分.后40年的结果分析表明,该耦合模式能够合理地模拟大气及陆地生态系统显著的年际变化.用奇异值分解(SVD)分析了东亚地区植被生长和气候变化的相互关系,发现在东业区域的植被净初级生产力(NPP)强弱的变化对血着大气环流的变化,特别是NPP分别与850 hPa的风场和500 hPa的高度场表现出很强的时空一致性.在东亚地区,由于植被类型的不同,导致NPP年际变化与降水、表面气温、短波辐射的年际变化的相关性不同,它们的年际变化与相关物理量场的年际变化表现出很强的植物种类的区别.     

医用CT增益可编程的多路高速数据采集系统设计

介绍了一种医用CT增益可编程的多路高速数据采集系统,该系统以FPGA为时序控制器,以ADC4344为模数转换器,通过串行移位寄存器控制多路模拟开关实现多路模拟数据的采集,并采用可编程增益放大器提高了系统的分辨率。该系统电路结构简单,对多路高速、宽动态范围的数据采集系统具有一定的通用性,可根据系统的需要进行扩展。     

珠江口盆地惠州地区A区块碳酸盐岩油气储层预测

珠江口盆地珠江组碳酸盐岩油藏在近年取得了勘探新突破,如LF15-1油藏的成功评价,极大地鼓舞了区域碳酸盐岩勘探。由于碳酸盐岩储层非均质性强、分布复杂,受古地形、沉积环境、成岩作用叠合影响,储层评价困难。笔者在前人研究的碳酸盐岩地层速度和储层孔隙度呈线性关系成果的基础上,充分挖潜地震资料计算碳酸盐岩地层速度对研究区储层发育区进行宏观分析,结合叠前叠后联合相控反演进行碳酸盐岩储层精细刻画,在研究区评价出3个有利储层发育区,识别出有利储层Ⅰ区是一个规模超过12km2的岩性圈闭,为区域后续勘探奠定了良好基础。     

Carbonate ramp depositional systems from a late Jurassic epeiric platform (Iberian Basin, Spain): a combined computer modelling and outcrop analysis

No counterparts to epeiric-sea carbonate ramps are known in present-day environments. This hinders the interpretation of the factors controlling the growth and evolution of these depositional settings. In this study we analyse the facies and geometries of two Jurassic examples both from outcrop study and through computer modelling. This analysis is constrained by two important features of these Oxfordian and Kimmeridgian ramps: firstly, they are very well exposed, allowing accurate reconstruction of a 200-km section from proximal to distal ramp environments, and, secondly, a time framework for correlation, section reconstruction and modelling is provided by a well-defined ammonite biostratigraphy. The modelling results in a synthetic stratigraphy which closely matches the reconstructed cross-sections and, when integrated with the field study, constrains and provides additional quantitative data on the following aspects of carbonate ramp systems. Resedimentation by storms is an important process in maintaining the ramp profile through time. Down-ramp transport distances of between 25 and 40 km are indicated from the distribution of storm beds and shallow-water allochems and from model-matching known stratigraphic thicknesses and geometries. Modelling sediment production within the time constraints from the ammonite biozones indicates that shallow-water carbonate production was 1–2 orders of magnitude less than that predicted for present-day open-marine carbonate platforms. Deeper-water production rates were reduced by lesser amounts. These proportionally higher, outer-ramp production rates also help to maintain ramp geometries through time. The enigmatic slope crest of ramps is shown to result from a combination of higher, shallow-water production and erosion rates, together with loss of accommodation during highstands and high-stillstands in the modelled sea-level curves. The most parsimonious modelling of the two ramp sequences comes from a relative sea-level curve composed of a linear subsidence component superposed by 20- and 100-kyr cycles on a third-order cycle. The third-order cycles and their timing do not correspond to those of the Exxon curve.     

Response of Growing Season Gross Primary Production to El Ni?o in Different Phases of the Pacific Decadal Oscillation over Eastern China Based on Bayesian Model Averaging

Gross primary production (GPP) plays a crucial part in the carbon cycle of terrestrial ecosystems. A set of validated monthly GPP data from 1957 to 2010 in 0.5° × 0.5° grids of China was weighted from the Multi-scale Terrestrial Model Intercomparison Project using Bayesian model averaging (BMA). The spatial anomalies of detrended BMA GPP during the growing seasons of typical El Ni?o years indicated that GPP response to El Ni?o varies with Pacific Decadal Oscillation (PDO) phases: when the PDO was in the cool phase, it was likely that GPP was greater in northern China (32°–38°N, 111°–122°E) and less in the Yangtze River valley (28°–32°N, 111°–122°E); in contrast, when PDO was in the warm phase, the GPP anomalies were usually reversed in these two regions. The consistent spatiotemporal pattern and high partial correlation revealed that rainfall dominated this phenomenon. The previously published findings on how El Ni?o during different phases of PDO affecting rainfall in eastern China make the statistical relationship between GPP and El Ni?o in this study theoretically credible. This paper not only introduces an effective way to use BMA in grids that have mixed plant function types, but also makes it possible to evaluate the carbon cycle in eastern China based on the prediction of El Ni?o and PDO.