基于分段函数法计算湿球温度研究

核电厂冷却塔设计气象条件中,湿球温度是重要的设计气象参数之一。近年来,由于实行自动观测,相对湿度值由仪器自动测定,因此不少气象站已经停止了湿球温度的观测,这给电厂气象参数的分析计算造成了一定困难。为此,根据气压分布型特点和分段函数,提出利用干球温度和相对湿度来计算湿球温度的新方法,经河南省郑州、南阳和商丘3站的应用,效果良好。     

湿球温度循环迭代算法及其应用

许多大型能源项目的前期可行性论证工作都必须计算干湿球温度的设计参数,但从2001年开始,按照中国气象局的要求,安徽省各台站陆续将干湿球温度表更换为湿敏电容传感器,至2007年,所有台站的自动观测设备安装完毕.新的自动观测仪器对湿球温度不再进行观测.为了解决缺少资料的问题,设计了一种计算湿球温度的循环迭代算法,并把结果数据与查表计算的结果相比较,误差小于0.1℃的占92.52%,小于0.2℃的占99.49%,结果可靠,与传统查表方法相比,具有方便快捷的特点,适合作为补充历史湿球温度序列的方法,满足了气候应用服务的需要,可以在电站设计标准计算上得到广泛的应用,也可以作为地面历史资料审核程序的有益补充.     

湿球温度计算方法及序列连续性研究

湿球温度是许多大型工程设计的重要参数,是影响工程安全、投资成本和运营效益的关键因子。停止观测后,寻求合理的湿球温度计算方法及对其的连续性研究迫在眉睫。文章选取牛顿迭代法和最优逼近法,基于江苏省70台站1991—2001、2004年(及13站长年代——近40年)的观测数据检验两种方法的估算偏差及探讨资料的连续性应用。最优逼近法的计算精度高,离散度低,与湿球温度的观测记录吻合好(90.8%~100%),显著优于牛顿迭代法(12.7%~20.1%),且呈现出09—20时符合率较高,日出前后符合率较低的变化特征。近40年的长年代对比分析表明,最优逼近法的计算结果稳定性好,在一定程度上可替代湿球温度的观测值,估算效果在温度高时较好,温度低时相对较弱;并且基于最优逼近法,利用百叶箱柱状干湿表数据估算的时间序列,相对长年代数据的不均一性,对湿球温度数据的连续性研究更为可靠。     

大畈核电站拟址空气湿球温度推算

确定最终热阱系统的容量时,必须规定设计基准气象参数,首先确认了内陆核电站最终热阱关键气象参数之一为空气湿球温度.选取湖北大畈核电站拟选站址所在地通山县气象站的三种湿球温度数据序列--近10年最热月日最高值、历年最热月日最高值、历年最高值,分别用对数、Gumbel及多项式等3种曲线进行概率拟合,并分别计算了不同重现期的参数值.结果表明:日资料拟合的极值略高于历年最高值的拟合结果,历年最高值的拟合值更接近于实际情况;多项式拟合尽管拟合效果好,但有一个不可突破的最大值,显然具有局限性;选取近10年最热月日最高值进行拟合,可以弥补缺乏长期观测的不足;Gumbel曲线拟合概率误差比对数曲线的小.最终推荐采用Gumbel曲线对历年最高值进行拟合,湖北大畈核电站50年、100年、500年、1000年重现期湿球温度的极值分别为:30.3℃、30.5℃、31.1℃和31.3℃.     

黄山市暴雨强度公式的研制

利用黄山市屯溪气象站1987～2016年连续30a的降水观测资料,获得降水量统计样本;采用"年最大值法"进行资料选样,按照P—Ⅲ分布、耿贝尔分布和指数分布进行分布曲线拟合得到雨强—重现期—历时(i-P-t)三联表;采用最小二乘法、高斯牛顿法求解暴雨强度分公式和总公式参数,根据误差最小原则确定最优方法,得到黄山市暴雨强度公式。结果表明:耿贝尔分布和指数分布各降水历时下的相对均方根误差比P-Ⅲ分布较小;采用最小二乘法参数组合方法计算分公式和总公式误差比高斯牛顿法较小,精度满足国标要求,是目前较为合适的暴雨强度公式计算方法,推荐为最优的暴雨强度公式。     

两种湿球温度估计方法比较及误差分析

由于我国地面气象观测系统的自动化,停止了湿球温度要素观测.为解决无湿球温度资料给工程设计带来的问题,分别设计了逼近法和多元回归法估计湿球温度.逼近法利用湿球温度与气压、温度、相对湿度的关系,并通过数值求解方法实现;多元回归法以气压、温度、相对湿度、水汽压等要素为因子,建立估计湿球温度回归方程.基于全国134个基准气象站...     

乌兰察布市气象资料应用处理与共享技术分析

乌兰察布市气象资料应用处理与共享系统,以该市已经建成的自动气象站实时监测数据为信息资源,充分利用信息网络通讯技术和数据库存储与查询、分析、统计技术,实现全市气象部门自动气象站资料的整合与管理。通过气象资料应用处理与共享平台的建设,实现了气象资料在全市气象部门内的高效共享,并提高了气象资料在业务领域和服务领域的使用率和共享率。     

GPRS自动站数据传输的可行性分析

GPRS支持因特网上广泛应用的TCP/IP协议和X.25协议,作为专业数据的无线网络传输技术,被广泛的应用于各种无人自动气象站。本文分析了GPRS无线网络在气象台站资料传输中应用的特点,并通过实验在OSSMO2004地面气象测报业务软件中利用移动GPRS实现了自动气象站实时资料及天气报文的传输。     

南宁市气象站拟迁站新站址对比观测资料分析

采用差值统计方法,对南宁市气象观测站、田东县气象观测站、邕宁县气象观测站、五合区域自动气象站2011年1到12月同期资料及南宁市气象观测站1991至2010年20年月平均值资料进行对比分析,以为南宁市气象观测站的观测资料序列延续和台站迁站提供参考.     

湖北省荆门市城区新一代暴雨强度公式的研制

利用湖北省荆门市气象站1974—2014年分钟降水数据,采用"年最大值法"进行资料选样,采用指数分布、耿贝尔分布和P-Ⅲ分布进行分布曲线拟合得到雨强一历时一重现期(i-t-T)三联表,采用最小二乘法、高斯牛顿法求解暴雨强度分公式和总公式参数,根据误差最小原则确定最优方法,并将新公式与现用公式计算所得雨强进行比较。结果指出:P-Ⅲ分布各降水历时下的相对均方根误差较小;采用P-Ⅲ分布、最小二乘法参数组合方法计算分公式和P-Ⅲ分布、高斯牛顿法参数组合方法计算总公式误差较小;新分公式和总公式较现用公式算出的对应雨强整体偏大。建议相关排水规划部门在设计地下管网时加大管径的设计。目前,该公式经荆门市政府同意已发布执行。     

LOW-FREQUENCY CIRCULATION AND EXTENDED-RANGE FORECAST IN CONNECTION WITH AUTUMN EXTREME HEAVY RAINFALL PROCESS IN HAINAN

Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.     

AN ATTRIBUTION ANALYSIS OF CHANGES IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING–TIANJIN–HEBEI REGION UNDER CLIMATE CHANGE

Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.     

ANALYSIS OF “BIMODAL PATTERN” STORM ACTIVITY CHARACTERISTICS OF THE BAY OF BENGAL

Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.     

CHARACTERISTICS AND TRENDS OF CLIMATIC EXTREMES IN CHINA DURING 1959–2014

The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.     

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正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.SUBMISSIONAll submitted     

A Brief Introduction to Marine Meteorological Science Experiment Base at Bohe Town,Maoming City,Guangdong Province

<正>With the support of specialized funds for national science institutions,the Guangzhou Institute of Tropical and Marine Meteorology,China Meteorological Administration set up in October 2008 an experiment base for marine meteorology and a number of observation systems for the coastal boundary layer,air-sea flux,marine environmental elements,and basic meteorological elements at Bohe town,Maoming city,Guangdong province,in the northern part of the South China Sea.     

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AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome.     

Information for Authors

AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome.     

Information for Authors

正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences