地面测报业务软件现状及发展趋势

地面测报业务软件现状及发展趋势汪勇进（安徽省桐城气象局，２３１４１０）引言自计算机引人气象测报业务后，测报质量得到了显著提高，减轻了观测员的劳动强度，深受广大观测员的欢迎。随着计算机产业的迅猛发展，气象台站的机型已由初期的ＰＣ－１５００和ＡＰＰｌｅ一...     

怎样实施新的农业气象观测规范

怎样实施新的农业气象观测规范周志香（山西省气科所，省农业气象中心０３０００２）国家气象局气候司农气处组织有关专家，历经数年编写的新的农业气象观测规范，即将开始实施。农气观测员怎样才能把新规范不折不扣地贯彻到工作中去呢？我认为，除了争取领导的重视和支持...     

EOS/MODIS遥感数据的接收与处理

提高地面测报工作的质量，在短期内也许是易事，而要长期保持高质量的地面测报工作则决非易事。我经过８年的地面测报值班工作（从观测员到预审员再到分管业务的副局长），初步摸索出５点体会。１有高度的工作责任感和正确的职业道德观念每一个观测员都知道测报工作的宗旨是什么，目的是什么，《地面观测规范》中的内容是什么，但如果不把这些落实在行动上，于是，迟测、早测者有之；涂改伪造者有之；天气现场不连续观测随便记录者有之；冬季不溶冰观测者有之等。因此所获得的资料也就失去其真实性。如果每个观测员都有高度的工作责任感和正…     

Gstar-Ⅰ型自动土壤水分站一次故障处理

<正>洛川国家基准站使用Gstar-Ⅰ型自动土壤水分观测仪。该仪器运行以来,不但提高了观测数据的时空密度,而且很大程度减轻了观测员的劳动量。Gstar-Ⅰ型自动土壤水分观测仪传感器安装在室外,通过4芯电缆使用RS485通讯模块与室内采集器和专用控制计算机连接。但是由于其传感器安装在室外,传输电缆较长,设备难免发生故障。本文以洛川国家基准站Gstar-Ⅰ型自动土壤水分观测仪的一次故障排除为例,阐述排除这类故     

土壤水文物理常数测定应注意的几个问题

在农业气象观测中,土壤水文物理常数的测定非常重要,其测定方法技术性强,观测员不容易掌握,且因人为因素容易出现偏差。结合十多年来全省多次土壤水分测量培训和在各个地区土壤水文物理常数测定中的实际经验,介绍了以《农业气象观测规范》为标准的土壤水文物理常数测定的实用方法,为农业气象观测人员提供参考。     

就如何做一名优秀观测员的几点浅识

就如何做一名优秀观测员的几点浅识刘学军（阳城县气象局０４８１００）１９８８年参加工作，我就一直从事地面测报工作。在７年多的测报实践中，自己虽然取得了一些成绩，但缺点也不免存在。下面我就对如何做一名优秀的观测员淡几点粗浅认识。１优秀观测员的前提条件树立...     

TDR──一种测定土壤湿度的最新仪器

TDR（TimeDomainReflectometry），即时城反射水分测量仪，是8O年代后期出现的一种能快速测定土壤水分含量的新仪器。近几年，我国的一些科研机构也开始引进这一技术。这一技术的探测原理为土壤基质的介电常数（ka）与容积含水量密切相关。水的介电常数较高（Ka=80）。与土壤（ho丝3－5）和空气（Ka=l）相比，水的人在土壤中处于支配地位，因此土壤湿度越高，ha值越大，沿波导的电磁波传播时间就越长，因此通过测定土壤中电磁波沿波导的传播速度就可以确定土壤容积含水量。具体测量时是由同轴电缆线末端的两根（或3根）不锈钢棒（波导）…     

用微机制作本站气压和海平面气压查算简表和程序设计

用微机制作本站气压和海平面气压查算简表和程序设计王凤刚（九台市气象局）自１９８７年４月，吉林省各基层气象站在地面测业务中开始使用ＰＣ—１５００微机计算和编发电报。这样，大大减轻了观测员的工作量，错情率也相应减少。ＰＣ—１５００微机经过七年多的使用，许...     

土壤湿度数据处理及资料查询系统

土壤湿度数据处理及资料查询系统张青珍杨光仙李红卫白宇樊瑞峰（郑州市气象局·４５００６１）（河南省气象局）１引言土壤水分是植物耗水的直接来源,对植物的生理活动有重大影响。进行土壤水分状况测定,掌握土壤水分变化规律,对农业生产实时服务和理论研究都具有重要...     

GStar-Ⅰ型自动土壤水分观测仪故障快速诊断及解决办法

近年来,地面自动气象探测设备全面投入业务应用,围绕设备保障诊断及排除进行了一些研究。GStar-Ⅰ型自动土壤水分观测仪（以下简称土壤水分仪）是近年陕西气象部门启用的自动测定土壤水分常规仪器之一。     

The numerical scheme development of a simplified frozen soil model

In almost all frozen soil models used currently, three variables of temperature, ice content and moisture content are used as prognostic variables and the rate term, accounting for the contribution of the phase change between water and ice, is shown explicitly in both the energy and mass balance equations. The models must be solved by a numerical method with an iterative process, and the rate term of the phase change needs to be pre-estimated at the beginning in each iteration step. Since the rate term of the phase change in the energy equation is closely related to the release or absorption of the great amount of fusion heat, a small error in the rate term estimation will introduce greater error in the energy balance, which will amplify the error in the temperature calculation and in turn, cause problems for the numerical solution convergence. In this work, in order to first reduce the trouble, the methodology of the variable transformation is applied to a simplified frozen soil model used currently, which leads to new frozen soil scheme used in this work. In the new scheme, the enthalpy and the total water equivalent are used as predictive variables in the governing equations to replace temperature, volumetric soil moisture and ice content used in many current models. By doing so, the rate terms of the phase change are not shown explicitly in both the mass and energy equations and its pre-estimation is avoided. Secondly, in order to solve this new scheme more functionally, the development of the numerical scheme to the new scheme is described and a numerical algorithm appropriate to the numerical scheme is developed. In order to evaluate the new scheme of the frozen soil model and its relevant algorithm, a series of model evaluations are conducted by comparing numerical results from the new model scheme with three observational data sets. The comparisons show that the results from the model are in good agreement with these data sets in both the change trend of variables and their magnitude values, and the new scheme, together with the algorithm, is more efficient and saves more computer time.     

浅谈计算机病毒的预防工作

本文针对目前气象业务工作中常常会遇到计算机被病毒感染的情况，提出了一些预防病毒感染的方法，以减少计算机病毒对业务工作的不利影响。     

基于CLM4.5模式的季节冻土区土壤参数化方案的模拟研究

利用位于季节冻土区的中国科学院那曲高寒气候环境观测研究站那曲/BJ观测点的野外观测数据,通过CLM4.5的单点模拟实验,分析评估了Luo土壤热导率参数化方案、Johansen土壤热导率参数化方案、Coté土壤热导率参数化方案和虚温参数化方案对土壤温、湿度的模拟能力,为将来选取最优的参数及参数化方案来更合理的模拟青藏高原土壤冻融过程为目的的工作提供依据。结果表明:(1)三种土壤热导率参数化方案模拟结果的土壤热传导率有明显差异,其中Coté方案的土壤热传导率最高,Luo方案的土壤热传导率最低。(2)三种热传导率方案均能合理地模拟出土壤温湿度的日变化趋势,Johansen方案对土壤温度年变化趋势模拟的更好,Coté方案对土壤温度模拟的数值较观测值偏离的更小,Luo方案对土壤湿度的模拟更好。(3)加入虚拟温度方程,并引入相变效率参数后,减少了模式对土壤湿度模拟的负偏差,Y-L方案在保持土壤温度较好模拟能力的基础上,能够进一步的提升土壤湿度的模拟能力。     

水地春小麦全生育期地膜覆盖节水增产效果初探

本文通过试验研究,初步肯定了全生育期地膜覆盖对水地春小麦的节水增产效果。初步看出其节水增产的机理为:地膜覆盖的增(地)温和保墒作用,增加了春小麦幼苗期的干物质积累和叶面积,促进了根系的生长发育;并使出苗提早,促进延长了穗分化,起到增粒作用;同时使千粒重也有所增加,从而达到增产;由于保墒作用及头水的推迟,减少了灌溉定额和灌溉次数及耗水量,因此具有明显的节水效果。通过对两年试验所建立的回归模型进行计算机选优,得出了节水、节种、增产的优化栽培措施组合为:头水叶龄4～4.5叶,二水时期为开花,全生育期灌水2次,灌溉定额155～200方/亩,播种23～32万粒/亩,施氮10公斤左右,氮磷比1∶0.5～0.7,但对地膜复盖技术还需继续研究,继续提高其经济效益,同时上列措施组合尚待进一步完善和经生产验证。     

河南省自动土壤水分观测网的建设与运行管理

河南省是产粮大省,但是粮食生产时常受到旱灾的影响。为满足新时期抗旱工作的需要,河南省气象局自2009年开始布设自动土壤水分观测站,截至2010年年底在作物地段安装127部,在固定地段安装11部,自动土壤水分观测站网覆盖了全省120多个县区,形成了较为有效的土壤水分与干旱监测网络。为了实现高效管理、设备及时维护、确保自动...     

冬小麦夏玉米土壤水分预报及优化灌溉模型

利用土壤水分平衡方程，结合河南省冬小麦和夏玉米的生长规律和1994～2000年冬小麦、夏玉米田实测土壤湿度资料，建立了河南省冬小麦、夏玉米土壤水分预报及优化灌溉的计算机模型。用1998～1999年郑州市麦田实测土壤湿度资料验证该模型模拟结果，未来10、20、30天土壤湿度相对误差分别为-7．3％～7．7％、-8．3％～6．8％、-7．6％～7．7％，表明利用该模型，可以较为准确地预报未来1个月的土壤水分变化，并可根据小麦、玉米不同发育期特点，给出以最高产量和最佳经济效益为目标的灌溉建议。     

Impact of Land Surface Heterogeneity on Mesoscale Atmospheric Dispersion

Prior numerical modelling studies show that atmospheric dispersion is sensitive to surface heterogeneities, but past studies do not consider the impact of a realistic distribution of surface heterogeneities on mesoscale atmospheric dispersion. While these focussed on dispersion in the convective boundary layer, the present work also considers dispersion in the nocturnal boundary layer and above. Using a Lagrangian particle dispersion model (LPDM) coupled to the Eulerian Regional Atmospheric Modeling System (RAMS), the impact of topographic, vegetation, and soil moisture heterogeneities on daytime and nighttime atmospheric dispersion is examined. In addition, the sensitivity to the use of Moderate Resolution Imaging Spectroradiometer (MODIS)-derived spatial distributions of vegetation characteristics on atmospheric dispersion is also studied. The impact of vegetation and terrain heterogeneities on atmospheric dispersion is strongly modulated by soil moisture, with the nature of dispersion switching from non-Gaussian to near-Gaussian behaviour for wetter soils (fraction of saturation soil moisture content exceeding 40%). For drier soil moisture conditions, vegetation heterogeneity produces differential heating and the formation of mesoscale circulation patterns that are primarily responsible for non-Gaussian dispersion patterns. Nighttime dispersion is very sensitive to topographic, vegetation, soil moisture, and soil type heterogeneity and is distinctly non-Gaussian for heterogeneous land-surface conditions. Sensitivity studies show that soil type and vegetation heterogeneities have the most dramatic impact on atmospheric dispersion. To provide more skilful dispersion calculations, we recommend the utilisation of satellite-derived vegetation characteristics coupled with data assimilation techniques that constrain soil-vegetation-atmosphere transfer (SVAT) models to generate realistic spatial distributions of surface energy fluxes.     

Soil erosion in the West African Sahel: a review and an application of a “local political ecology” approach in South West Niger

A review of soil erosion research in the West African Sahel finds that there are insufficient data on which to base policy. This is largely because of the difficulties of measuring erosion and the other components of “soil life”, and because of the highly spatially and temporarily variable natural and social environment of the Sahel. However, a “local political ecology” of soil erosion and new methodologies offer some hope of overcoming these problems. Nonetheless, a major knowledge gap will remain, about how rates of erosion are accommodated and appraised within very variable social and economic conditions. An example from recent field work in Niger shows that erosion is correlated with factors such as male migration, suggesting, in this case, that households with access to non-farm income adopt a risk-avoidance strategy in which soil erosion is accelerated incidentally. It is concluded that there needs to be more research into the relations between erosion and socio-economic factors, and clearer thinking about the meaning of sustainability as it refers to soil erosion in the Sahel.     

Simulating evapotranspiration in a semi-arid environment

Summary In this work, simulations with the mesoscale meteorological model FOOT3DK for a semi-arid research site in southern morocco are presented. The main aim of this study is to introduce two different ways to improve the soil moisture distribution towards a more realistic pattern. One of them resembles the availability of groundwater resources below the lower boundary of the soil part of the model, the other one resembles irrigation practices in the region. Additionally, we introduce a newly derived land use/land cover data set obtained from analysis of LANDSAT data and compare the simulation results to those obtained with the USGS GLCC data. To evaluate the results with the refinements in soil moisture and land use/land cover, we focus on evapotranspiration, as the quantity which is most tentative to the changes in soil moisture and is an important part of the local hydrological cycle. To evaluate the importance of sub-grid scale surface heterogeneity in soil moisture and land use/land cover, we present simulations with enhanced surface resolution. Simulation results are compared to point measurements at different sites in the research area for validation.The results show, that a deep groundwater table and irrigation of parts of the research area can be represented by the methods we used. Simulated transpiration is overestimated compared to measured values, but this is due to the maximum approach used in this work. Finer tuning of the artificial enhancement of soil moisture with the two methods presented here are expected to lead to realistic distributions of evapotranspiration and related quantities, therewith drastically enhancing simulation accuracy for this site. As uncertainties of soil moisture distribution and restricted representation of soil moisture dynamics in meteorological models is a common problem especially for arid and semi-arid sites, we expect our results to be useful for meteorological simulations in other arid or semi-arid areas as well.     

陆面过程模型中垂直非均匀土壤的水分传输及相变的模拟

土壤湿度在陆气相互作用中的重要性体现在它既能影响陆地和大气之间水循环的速率, 又能改变地表的能量分配。本文针对陆面过程模型中描述土壤湿度变化的方程进行了理论分析, 指出在非均匀土壤和冻土中采用土壤水势梯度描述垂直非均匀土壤水分流动的合理性。基于描述土壤内部水热传输的统一土壤模型, 并利用推广的表征土壤水分特征的Clapp-Hornberger关系式, 研究了非冻结和冻结的土壤湿度对于垂直非均匀土壤的敏感性。结果表明, 由土壤质地决定的土壤水势和导水率对土壤湿度的模拟有重要的影响。具体地, 在决定土壤性质的Clapp-Hornberger关系式中, 与土壤质地有关的饱和水势、饱和导水率以及土壤孔隙大小分布指数B, 对土壤湿度的模拟起到了关键作用。参数B的重要性尤为突出, 它的增加会引起导水率的大大下降, 从而对水分在土壤中的垂直分布产生重要影响。饱和水势的绝对值和参数B的增加会使得土壤水势绝对值增加明显, 使土壤的结冰(融化)过程延迟, 土壤温度因为没有结冰(融化)释放(吸收)的潜热加热(冷却)而持续下降(上升), 因此在冻融时期土壤温度会比观测值振幅偏大。上述结果揭示了考虑土壤垂直非均匀性并采用有效的土壤特性参数对于陆面过程模型的重要性。