T106数值预报产品在赣南温度预报中的释用

利用1995年7～9月、1996年7～8月24～144h、1000～500hPa的T106格点资料与赣南17个县（市）的最高、最低、平均温度作相关分析;用逐步回归方法建立了分县逐日滚动预报方程。并用1996年9月份T106格点资料对方法进行检验,同时对预报方法及T106产品在温度预报中的释用能力作了初步分析。     

雹云判别和适宜作业时机分析

人工防雹作业中关键是雹云判别和适时作业。雹云判别用4因子组合表征雹云特征，还能判别雹落区；在cb云路径上确定查强区进行雹云判别，以决定适时作业的时间。     

Review of measurements of the RF spectrum of radiation from lightning

Summary A review is presented of the measurements reported in the literature of the spectrum of electromagnetic radiation from lightning in the frequency range from 1 kHz to 1 GHz. Measurements have been made either by monitoring the power received at inidividual frequencies using a narrow bandwidth recording device or by recording the transient (time dependent) radiation with a wide bandwidth device and then Fourier transforming the waveform to obtain a spectrum. Measurements of the first type were made extensively in the 1950's and 1960's and several composite spectra have been deduced by normalizing the data of different investigators to common units of bandwidth and distance. The composite spectra tend to peak near 5 kHz and then decrease roughly as 1/(frequency) up to nearly 100 MHz where scatter in the data make the behaviour uncertain. The spectrum obtained with measurements of the second type is similar. Recent experiments have extended the frequency range covered to several 10's of MHz and include spectra for return strokes, the stepped leader and for some intracloud processes. The spectrum of first return strokes obtained in this manner is very similar to the spectrum of the composite flash obtained from the narrowband measurements.With 9 Figures     

A study of spatial structure of conditions of river network formation

Catchments of first-order streams in the Chita River basin in Zabaikal’skii krai are studied in order to reveal the spatial structure of conditions influencing the river network formation. The river network construction was carried out using the TAS GIS (Terrain Analysis System Geographic Information System) software and SRTM (Shuttle Radar Topographic Mission) digital terrain model. The comparison of the TAS river network with the river network of topographic maps enables to reveal the distribution of conditions of river network formation for the territory of the basin as well as the type and degree of their impact on the surface runoff. The obtained data enabled to group the basin streams according to these conditions and to reveal favorable and unfavorable areas for the first-order stream initiation.     

Numerical simulation of the scavenging rates of ice crystals of various microphysical characteristics

Numerical models of trajectories of small aerosol spheres relative to oblate spheroids were used to determine ice crystal scavenging efficiencies. The models included the effects of aerodynamic flow about the ice particle, gravity, aerosol particle inertia and drag and electrostatic effects. Two electric configurations of the ice particle were investi-gated in detail. The first applied a net charge to the ice particle, of magnitude equal to the mean thunderstorm charge distribution, while the second applied a charge distribution, with no net charge, to the ice particle to model the electric multipole charge distribution. The results show that growing ice crystals with electric multipoles are better scavengers than single ice crystals with net thunderstorm charges, especially in the Greenfield gap (0.1 to 1.0 μm), and that larger single crystals are better scavengers than smaller single crystals. The results also show that the low density ice crystals are more effective scavengers with net charges than they are with charge distribution.     

温室黄瓜生育期模拟模型的研究

根据黄瓜（Cucumis sativus）发育的光温反应过程,建立了基于生理发育时间的黄瓜生育期模拟模型,并利用不同品种的试验资料对模型进行了检验。结果表明,黄瓜从播种到第一批瓜成熟需积累生理发育时间30d,播种—幼苗、幼苗—伸蔓、伸蔓—开花、开花—结瓜、结瓜—成熟所需的生理发育时间分别为3、11、9、5、2d。发芽期、幼苗期、伸蔓期、开花期、结瓜期等各生育期持续时间的模拟值与实际观测值的回归估计标准误差（root mean squared error;RMSE）分别为0、2．6、1．7、0．8、2．1d,从播种到第一次采收的模拟值与观测值的RMSE为1．4d。而用有效积温法对发芽期、幼苗期、伸蔓期、开花期、结瓜期等各生育期持续时间的模拟值与实际观测值的RMSE分别为0．7、10．0、5．7、2．4、2．5d,从播种到第一次采收的模拟值与观测值的RMSE为22．0d。本模型比用有效积温法能更准确地预测黄瓜各个生育期的起止日期和黄瓜的收获期。     

Stabilization of Atmospheric Concentrations of Greenhouse Gases

Given the present commitment of the developed countries according to the Kyoto Protocol, most published scenarios demonstrate that global greenhouse gases concentrations would not be stabilized at any level. In order to stabilize these concentrations, a deeper global involvement is needed. Taking Israel as an example of a `recently-developed' country, we assess the role that such countries could play by assuming voluntary commitments in strengthening global involvement. This case as a model may encourage a global scheme for curbing carbon emissions, in which the more developed countries assume a stronger role and the less developed countries participate according to the principle of common but differentiated responsibility. The scheme builds on the inverse relation that exists between the per capita gross domestic product and the rate of increase of emissions due to economic growth. According to this theoretical scheme, the voluntary commitments assumed by the `recently-developed' countries encourage the more developed countries to deepen their involvement by assuming more stringent reductions of emissions at home and transferring technological and financial means to the less developed countries. The proposed scheme would enable non-Annex I countries, both `recently-developed' countries and less developed countries, to participate much earlier in the net mitigation of greenhouse gases.     

台风“巨爵”近海急剧加强的特征及成因分析

源自东风波动的0915号台风"巨爵"在自东向西靠近广东沿海时出现了近海急剧加强的异常现象。利用热带气旋定位资料、NCEP全球同化分析资料、卫星云图以及海上平台自动站探测资料等对"巨爵"近海加强特征和成因进行了诊断分析。结果表明:"巨爵"形成源自于西太副高南侧的东风波动,副高演变及引起的"北高南低"和"东高西低"的形势与"巨爵"环流增强发展密切相关;弱的垂直风切变、高空明显的辐散出流以及台风中心正涡度增大并向对流层中上层拓展有利于"巨爵"强度增强;低层弱冷空气南下,一方面从增加气压梯度和温度梯度来加强台风环流和暖心结构,另一方面通过触发外围对流云团发展并往台风中心输送进而对"巨爵"近海加强产生重要的触发作用;孟加拉湾西南季风气流、105°~110°E附近越赤道气流和西太副高西侧东南气流3支气流汇合为"巨爵"近海加强提供了充沛水汽条件。     

RG13型雨量传感器测量结果的不确定度评定

国内民航机场主要使用的雨量观测设备为芬兰维萨拉公司生产的RG13型雨量传感器,为保证雨量测量数据的真实可靠,对其测量结果的不确定度分析很有必要。根据自动气象站现场校准方法,分别进行大雨强和小雨强的重复测试,并依据JJF1059.1-2012测量不确定度的评定与表示要求,进行A类不确定度评定。分析测量过程中的B类不确定度来源,进行B类评定,最终给出扩展不确定度。结果表明：在小雨强下,测量不确定度为U95=0.17mm,包含因子k=2。在大雨强下,测量不确定度为U95=0.16mm,包含因子k=2。该研究完善了雨量传感器的现场校准工作流程,对雨量传感器测量结果的可信度评定具有参考价值。     

Calibration of sunphotometer for measurements of turbidity

Summary This study investigates an alternative method to the Langley plot, a widely used but complex calibration method for sunphotometers. A sunphotometer has been calibrated using two different methods: the Langley method, a calibration to the extraterrestrial irradiance, and second by comparison to a standard instrument. The standard instrument used for these studies is spectrophotometer. The relative difference between the calibration factors obtained by the two methods is between 0.13% for the channel with the greatest sensitivity (500 nm) and 2% for the channel with the lowest signal (368 nm). The accuracy of both calibrations is of the same order of magnitude with relative errors between 1.2 and 7% for the Langley method and 2.9 to 5.3% for the standard instrument method. Analyses of the origin of possible errors show the sensitivity of the Langley method to less than ideal weather conditions, which could cause an error in calibration of up to 45% under extreme conditions and when too few measurements are made. This studies are made only for the UV and the visible range, investigations about the application of this technique in the near IR have still to be done and would also require spectrometers with a wider sensitivity range.These investigations do not alter the fact that frequent calibrations are still needed due to sensitivity changes like filter degradation.With 6 Figures     

Analyses of the global distribution of precipitation

The global distribution of area-averaged precipitation is extremely difficult to determine with precision. In this paper we will explain why satellite measurements are necessary for the production of global analyses of precipitation, summarize some of the various methods which have been used to estimate rainfall from satellite observations over the past two decades, and describe an attempt to use a mix of remotely sensed estimates and surface observations of rainfall to produce analyses of the large-scale rainfall for the globe. We will discuss the relationship between two types of satellite-derived precipitation estimates over the oceans from 40°N to 40°S, and then will conclude with a discussion of some possible physical mechanisms which might be responsible for the observed correlation between area-averaged rainfall and cloudiness.     

降水对雾中能见度参数化的影响

雾的能见度是雾滴数浓度和含水量的函数,可以利用雾滴数浓度和含水量进行参数化得到能见度拟合值。但是当雾中有降水存在时,降水会影响雾滴数浓度和含水量,进而影响能见度参数化。2009年1月19日至3月5日在湖北恩施雷达站进行了包括雾微物理特征、雨滴谱及雨滴末速度、能见度以及基本气象要素的观测。利用不同的能见度参数化公式得到能见度拟合值,并与实测值进行对比分析,考虑雾中降水影响时的能见度拟合值要比不考虑降水时的能见度偏差大,因此在有降水伴随雾产生时,降水的效应可忽略不计。同时,利用40％的雾滴谱观测数据建立了良好的模型用于拟合当地的能见度,并利用Gultepe公式得到相应的参数,对当地的能见度进行了计算和预报。     

共轭方程理论在月平均温度距平季节预报中的应用

说明了共轭方程方法的可行性，使用历史资料代入共轭函数公式中计算了东北地区12月、6月月平均温度距平，并与实况进行了比较。为了建立东北地区12月、6月平均气温距平的长期预报方法，使用预报时间半年前的海温作参数化月平均热流量距平，代入简化的共轭函数公式中得到了预报值。     

Limitations of integrated assessment models of climate change

The integrated assessment models (IAMs) that economists use to analyze the expected costs and benefits of climate policies frequently suggest that the “optimal” policy is to go slowly and to do relatively little in the near term to reduce greenhouse gas emissions. We trace this finding to the contestable assumptions and limitations of IAMs. For example, they typically discount future impacts from climate change at relatively high rates. This practice may be appropriate for short-term financial decisions but its extension to intergenerational environmental issues rests on several empirically and philosophically controversial hypotheses. IAMs also assign monetary values to the benefits of climate mitigation on the basis of incomplete information and sometimes speculative judgments concerning the monetary worth of human lives and ecosystems, while downplaying scientific uncertainty about the extent of expected damages. In addition, IAMs may exaggerate mitigation costs by failing to reflect the socially determined, path-dependent nature of technical change and ignoring the potential savings from reduced energy utilization and other opportunities for innovation. A better approach to climate policy, drawing on recent research on the economics of uncertainty, would reframe the problem as buying insurance against catastrophic, low-probability events. Policy decisions should be based on a judgment concerning the maximum tolerable increase in temperature and/or carbon dioxide levels given the state of scientific understanding. The appropriate role for economists would then be to determine the least-cost global strategy to achieve that target. While this remains a demanding and complex problem, it is far more tractable and epistemically defensible than the cost-benefit comparisons attempted by most IAMs.     

改进的最优窗宽理论对年径流量的插值预测研究——以黄河利津等站为例

针对小样本数据造成年径流量预测效果不理想的情况,以及非对称和非正态资料的处理问题,引入信息扩散和模糊映射思想,同时运用遗传算法改进最优窗宽理论,建立了新的扩散插值模型。该模型通过对零散数据点的信息进行模糊扩散,进而实现对有限数据点信息向其邻近区域点的概率插值。选取黄河利津站为例,根据其近70 a(1942—2011年)径流量实测数据,进行了缺损数据的插值和预测试验,同时与正态扩散插值模型进行对比分析,结果表明:1)预测值能较好地模拟实际径流序列的波形变化,对丰水年(如2007年)和枯水年(如2009年)的预报都比较准确;2)中长期预报(10a)平均相对误差仅为11.59%,相较传统方法有较大的改进;3)以黄河流域2个站点(花园口和兰州)和长江流域的3个站点(朱沱、宜昌和大通)年径流量预测试验以及海温资料的插值试验作为补充,验证了该算法的有效性和普适性。该模型可为实际水文数据资料的客观分析和中长期预报提供参考。     

丹东地区大风气候事实分析

选取1980-2005年丹东地区4个测站的地面自记风记录,分析了大风时空分布特征,揭示了丹东地区大风的一些气候事实.丹东地区大风日数年际变化分3个阶段,1980-1991年正常偏少但波动较大,1992-1998年偏多,1999年以后明显减少;大风天气最多的季节是春季,以4月最多,其次是冬季,夏、秋季最少;大风最多风向是NNW,风向具有季节性差异;大风的空间分布与地形关系密切,沿海测站大风日数多于山区,且南大风日数居多.同时依据大风主要影响系统和天气形势特征,用天气学方法对大风进行了分型与分析.     

葡萄越冬防寒技术研究综述

葡萄冻害严重影响着我国北方葡萄的正常生产和品质,采取适宜的越冬防寒技术是确保葡萄产业健康发展的关键。通过查阅我国北方地区有关葡萄防寒越冬的相关方法和技术,以葡萄冻害入手,分别从覆盖保温被、保温膜、草帘等保温材料,埋土覆盖越冬防寒措施以及积雪覆盖的保温作用等多方面,分析对比了各防寒越冬技术的材料、原理、效果及优缺点。提出了以下建议:(1)葡萄安全越冬应采取因地制宜的措施,对于葡萄本身来说应采用综合的葡萄抗寒性锻炼,提高葡萄抗寒能力。(2)在探索不同地区切实有效、经济实惠的防寒越冬措施时,需要充分注重细节;不同覆膜技术和埋土技术应因地制宜,选择适合的安全越冬方式;在温度不是太寒冷的地区可采用机械埋土技术。(3)应该继续开发机械覆膜技术,以节约经济和劳力投入。(4)基于双层膜技术的保温效果及经济投入状况,以及自身在环保、耐磨以及人力投入较大等自身不足等特点,建议选择双层膜环保耐磨新材料,结合机械化覆膜新技术,在寒冷且风沙强烈的地区加以大力推广,这可能是未来葡萄防寒越冬措施的发展趋势。     

A Gcm Study of the Impact of Greenhouse Gas Increase on the Frequency of Occurrence of Tropical Cyclones

In order to make inferences on the possible future changes of tropical cyclogenesis frequency, we apply the diagnostic computation of the Yearly Genesis Parameter (YGP) proposed by Gray (1975) to the large-scale fields simulated by a GCM. The YGP is an empirical diagnostic of the frequency of Tropical Cyclones (TCs) based on six physical parameters computed from seasonal means of atmospheric and oceanic variables. In this paper, we apply the YGP diagnostic to the results of three climate simulations performed with the atmospheric General Circulation Model (GCM) of Météo-France: ARPEGE-Climat. In a control simulation of the current climate, it is shown that the model has a realistic tropical climatology and that the computed YGP reproduces the geographical distribution of the tropical cyclogenesis frequency. The YGP is then applied to two simulations corresponding to two scenarios of doubled carbon dioxide concentration. The two experiments differ by the sea surface temperatures (SSTs) used as a lower boundary condition. In both simulations the YGP gives a large increase of total cyclogenesis frequency, but without extension of the area of possible cyclone genesis. The increase in YGP is due essentially to the contribution of the ocean thermal energy factor in the thermodynamical potential. The dynamical parameters, on the contrary, limit the cyclogenesis increase and are a major explanation of the difference between the two experiments. This is in agreement with the results of the previous similar study of Ryan et al. (1992) concerning the importance of large-scale atmospheric circulation modifications on tropical cyclone climatology. After discussing the observed relationships between ocean surface temperature and large-scale convection, and questioning the use of a fixed temperature threshold in the diagnosis of tropical cyclone frequency, we propose a modification to the YGP consisting in replacing the thermodynamical potential by a term proportional to the convective precipitation computed by the GCM. For the simulation of the present climate this modification affects only marginally the geographical distribution of tropical cyclone genesis, but for the doubled CO₂ case, the modified YGP diagnoses a more limited increase in TC genesis in the Northern Hemisphere and a small reduction in the Southern Hemisphere, which seems in better agreement with other recent modelling studies with high resolution climate models (Bengtsson et al., 1996). We conclude that the modified YGP based on convective precipitation could serve as a useful diagnostic of tropical cyclone genesis, and should be tested in simulations with other GCMs.     

Observations of turbulence downwind of a forest-heath interface

The growth of the equilibrium layer downwind of a forest — heath interface has been observed using eddy correlation measurements made in real time. The atmosphere adjusts more quickly to the transition from heath to forest than to the transition from forest to heath.     

广西近百年气温和降水序列的多时间尺度分析

对广西近百年平均气温及降水量变化进行了多时间尺度的层次结构研究,并与Nino3区的海温距平进行奇异交叉谱分析。结果表明：平均气温有较强上升趋势并伴有明显的准两年周期振荡;降水则呈下降趋势,主要周期为32 a左右及准两年振荡。1884至1910年代初,广西处于干冷期;1910年代初至1930年前后,处于湿冷期;1930年前后至1950年代后期,处于湿暖期;1950年代后期至1990年代前期,处于干暖期。ENSO事件3~7 a的周期对广西平均气温及降水影响显著,赤道太平洋海温变化对广西气温的影响主要表现在年代际变化上,对降水的影响主要体现在年际变化上。