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以一些易被忽略、简化的指示性云状及编码为依据,论述云天演变,对于观测、记录及编码具有重要意义。 相似文献
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就百色工业立市的情况作简要概叙,并在工业立市进程中,除了决策和公益气象服务以外,气象信息服务的市场前景、营销人员队伍、服务中应注意的事项及气象信息服务的可能服务对象和内容作了较为详细的探讨。 相似文献
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综合布线系统采用标准化的语音、数据、图像、监控设备,各线综合配置在一套标准的布线系统上,统一布线设计、安装施工和集中管理维护。综合布线系统在广东省气象局核心网络升级综合布线实际应用效果明显。 相似文献
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综合布线系统在气象核心网络升级中的应用 总被引:11,自引:0,他引:11
综合布线系统采用标准化的语音、数据、图像、监控设备,各线综合配置在一套标准的布线系统上,统一布线设计、安装施工和集中管理维护。综合布线系统在广东省气象局核心网络升级综合布线实际应用效果明显。 相似文献
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The Impact Of Air-Flow Separation On The Drag Of The Sea Surface 总被引:2,自引:1,他引:2
An approach that allows assessment ofthe impact of air-flow separation (AFS) fromwave breaking fronts on the sea-surface drag is presented. Wave breaking fronts are modelled by the discontinuities of the sea-surface slope. It is assumedthat the dynamics of the AFS from wave breaking crests is similar to thatfrom the backward facing step. The form drag supported by an individualbreaker is described by the action of the pressure drop distributed alongthe forward face of the breaking front. The total stress due to the AFS isobtained as a sum of contributions from breaking fronts of different scales.Outside the breaking fronts the drag of the sea surface is supported by theviscous surface stress and the wave-induced stress. To calculate the stressdue to the AFS and the wave-induced stress a physical model of the wind-wavespectrum is used. Together with the model of the air flow described in termsof surface stresses it forms a self-consistent dynamical system for the seasurface-atmosphere where the air flow and wind waves are strongly coupled.Model calculations of the drag coefficient agree with measurements. It is shownthat the dimensionless Charnock parameter (roughness length normalized onthe square of the friction velocity and the acceleration of gravity)increases with the increase of the wind speed in agreement with fieldmeasurements. The stress due to the AFS normalized on the square of thefriction velocity is proportional to the cube of wind speed. At low windsthe viscous surface stress dominates the drag. The role of the form drag,which is the sum of the stress due to the AFS and the wave-induced stress, isnegligible. At moderate and high winds the form drag dominates. At windspeeds higher than 10 m s-1 the stress supported by the AFS becomescomparable to the wave-induced stress and supports up to 50% of the totalstress. 相似文献
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黑潮OLR距平指数与华南西部主汛期降水的关系 总被引:1,自引:0,他引:1
OLR距平场与华南西部主汛期降水的相关分析场显示,在黑潮区域有强烈的高相关信号反映。黑潮区OLR距平指数与华南主汛期降水的遥相关分析显示,前期黑潮区OLR距平指数的异常,可以成为预测主汛期降水有一定指示意义的前兆信号。并在此基础上建立主成分降维分析方法,对1989~2000年主汛期降水作预测及回代检验,检验结果准确率达75%,说明用黑潮区OLR距平指数作为预报因子可以取得良好的预报成绩。 相似文献
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Releases of halocarbons into the atmosphere over the last 50 years are among the factors that have contributed to changes in the Earth’s climate since pre-industrial times. Their individual and collective potential to contribute directly to surface climate change is usually gauged through calculation of their radiative efficiency, radiative forcing, and/or Global Warming Potential (GWP). For those halocarbons that contain chlorine and bromine, indirect effects on temperature via ozone layer depletion represent another way in which these gases affect climate. Further, halocarbons can also affect the temperature in the stratosphere. In this paper, we use a narrow-band radiative transfer model together with a range of climate models to examine the role of these gases on atmospheric temperatures in the stratosphere and troposphere. We evaluate in detail the halocarbon contributions to temperature changes at the tropical tropopause, and find that they have contributed a significant warming of ~0.4 K over the last 50 years, dominating the effect of the other well-mixed greenhouse gases at these levels. The fact that observed tropical temperatures have not warmed strongly suggests that other mechanisms may be countering this effect. In a climate model this warming of the tropopause layer is found to lead to a 6% smaller climate sensitivity for halocarbons on a globally averaged basis, compared to that for carbon dioxide changes. Using recent observations together with scenarios we also assess their past and predicted future direct and indirect roles on the evolution of surface temperature. We find that the indirect effect of stratospheric ozone depletion could have offset up to approximately half of the predicted past increases in surface temperature that would otherwise have occurred as a result of the direct effect of halocarbons. However, as ozone will likely recover in the next few decades, a slightly faster rate of warming should be expected from the net effect of halocarbons, and we find that together halocarbons could bring forward next century’s expected warming by ~20 years if future emissions projections are realized. In both the troposphere and stratosphere CFC-12 contributes most to the past temperature changes and the emissions projection considered suggest that HFC-134a could contribute most of the warming over the coming century. 相似文献
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The flux-gradient model, often used to describe turbulent dispersion, implicitly defines an eddy diffusion coefficient K that is known to be related to the Eulerian probability density function (pdf) of the turbulent velocity field. In the strict limit of applicability of Fick's law, the relationship between K and the pdf is used to investigate the influence of non-Gaussianity on dispersion in homogeneous turbulence. A bi-Gaussian pdf is used as a closure model that allows for separate studies of skewness and kurtosis variations. The choice of model parameters can have a significant influence on K, especially when the pdf is bimodal. Both arbitrariness of the closure and bimodality are then reduced using the maximum entropy criterion for the selection of the free parameter of the closure scheme, together with the assumption that the model is valid only for those values of the parameters for which a unimodal pdf is possible. The variations of K are found to be sensitive to both skewness and kurtosis showing a more complex behaviour than that found in literature. 相似文献
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在刚刚过去的2006年,是“十一五”规划的开局之年,是新农村建设的起步之年,也是黑龙江省全面建设小康社会发展进程中的重要一年。农业、农村经济持续快速发展,粮食总产量再创历史新高。农民收入连续大幅度增长。结构调整进一步深化,农村改革进一步推进,全省农村呈现出心气顺、尽头足、干群关系和谐稳定的良好局面。这些成绩当中凝聚着全省气象战线广大干部职工做出的重要贡献。过去的一年全省气象工作有了长足的发展,最重要的是国务院下发了《关于加快气象事业发展的若干意见》,省政府也提出具体意见,气象战线的同志们认真学习贯彻国务院的文件和省政府的意见,做了大量卓有成效的工作,气象预测预报准确,提出的对策、措施、建议很及时、很有建设性,气象服务的领域不断拓宽,从对生产服务更多的转向为人民生活服务,得到了人民的普遍好评。 相似文献
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结合部门实际。对江西气象部门如何领会和贯彻落实2005年全省领导干部会议精神,提出了具体的指导意见。讲话指出,全省各级气象部门干部职工,要把思想和行动进一步统一到全省领导干部会议精神上来,围绕为全民创业提供优质气象服务,找准自己的位置,为不同创业主体提供精细化、个性化的气象服务产品。拓宽为全民创业服务的气象信息传递渠道,强化安全气象和资源气象服务,开展全民创业技能培训和创业资讯服务,营造优化有利于全民创业的气象政务环境。努力满足全民创业对气象服务的迫切需求。讲话还强调,全省气象干部职工要强化创业理念,大力培育气象创业文化;加强气象能力建设,加快提升气象现代化水平和效益;适应中国气象事业发展战略,加快全省新一轮气象业务技术体制改革;坚持改革创新,做大做强做优气象科技服务;加强队伍建设,为事业发展提供智力支持和组织保证,努力在全民创业的热潮中,实现江西气象事业在新的起点上更快更好的发展。另外。讲话在总结分析上半年工作的基础上,结合全省领导干部会议精神。对2005年下半年的工作进行了全面的部署。认为2005年下半年,全省气象部门要狠抓目标管理,积极做好气象服务工作,下大力气促科技服务上新台阶;要加强与有关部门的共建共享工作。及时完成“十一五”规划的编制。大力推进业务技术体制改革和现代化建设;要加强党建和气象文化建设,并根据《江西省气象局关于加强基层台站建设的实施意见》,以及《全省县(市、区)气象局“五大工程”建设考评办法》。抓好基层台站建设。 相似文献
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从预警信号发布的重要性、发布渠道、宣传工作、技术支撑以及如何科学发布预警信号等五个方面,探讨预警信号发布工作中的一些问题,并初步提出一些相关的对策。 相似文献
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以45年生酥梨树为试材,分析测定塑料薄膜覆盖、树盘覆草、自然生草、定期灌水、清耕等不同土壤水分管理措施对土壤水分和酥梨品质的影响,结果表明不同处理间以塑料薄膜覆盖处理效果最好,不但果个较大,果实的固酸比值和产量也较高;树盘覆草次之,且具有土壤水分变化幅度较小和省工、省时等优点. 相似文献