高速公路路面温度极值预报模型研究

应用地表热量平衡方程,在太阳短波辐射、大气和地面长波辐射、感热和潜热等参数化方案的基础上,提出一种用于预报高速公路路面温度极值的数值模型.并利用沪宁高速公路梅村站和仙人山站2006年7月8日-12月31日的逐分钟的各要素实测数据对模型的有效性进行验证,结果表明:模型的平均绝对误差为1.32 ℃,预报误差在±3 ℃以内的频率高达85.23%,且对冬季路面温度低于0 ℃时的预报误差基本在-1～0 ℃,可以运用于冬季高速公路路面溜滑的实际预报中.     

银川城市道路路面温度变化特征及统计模型

采用人工定点观测路面温度资料,分析了不同天空状况和不同材质道路的路面温度日变化特征。结果表明：路面温度具有明显的日变化特征,晴空或少云时,日出和日落时段路面温度略高于气温,中午前后路面温度变幅最大,且明显高于气温;阴雨天时,路面温度略高于气温,变化相对平缓且与气温保持较好的相关性。由于水泥和沥青不同的物理特征,沥青路面对气温的反应灵敏,水泥路面反应平缓,即水泥路面最高温度多低于沥青路面,最低温度多高于沥青路面。在此基础上应用逐步回归方法建立逐时路面温度预报模型和最高道面温度预报模型,并应用模型模拟的结果与实测路面温度作对比分析,结果表明逐时道面温度预报模型的模拟效果较好,最高道面温度预报模型误差较大,需要进一步修正和改进。     

银川市路面温度预报与爆胎指数预报方法研究

利用7月份银川市沥青、水泥2种路面温度实测资料,研究了银川市水泥、沥青城市道路路面温度特征及其与气温、相对湿度、风等气象要素的关系,采用统计回归方法,建立了路面温度统计预报模型。在此模型基础上,分析了气温、车速和路面温度之间的关系,继而建立了爆胎指数分级预报方法和标准。结果表明：导致汽车爆胎的因素有很多,但当气温低于25℃时,即使是高速行驶的汽车,也不易因路面温度导致爆胎;而当气温高于35℃时,路面温度可高达70℃以上,此时车速在66km／h以上就有可能爆胎,车速超过82km／h时,爆胎的可能性非常大。通过对路面温度预报模型的检验表明,尽管建立的模型比较简单,也不能完全反应气象要素和路面温度之间更深层的关系,但是该模型的求解过程简单易懂,输人参数少且易于获得,可操作性强,预测精准度已满足业务需要,值得在业务中使用,在以后的业务中,通过不断的改进和完善,预报效果将得到进一步提升。     

基于BJ-RUC模式预报产品的北京冬半年道面温度预报模型

选用2012年11月1日至2013年3月30日3 km分辨率BJ-RUC模式输出的气象要素与5个道面站数据(A1027,A1325,A1412,A1414,A1512)温度进行统计分析,按不同起报时次(08、14和05时)分别建立三类逐步回归统计模型预报未来24 h逐时道面温度,选出最优模型预报2013年11月至2014年3月道面温度。结果表明:道面温度与RUC输出的2 m温度、短波辐射显著相关,与长波辐射、湿度次相关;有显著气象因子参与的回归模型预报的道面温度好于仅加入前一天对应时刻道面温度的回归模型,预报准确度可提高25%以上,误差减少1℃以上;滚动筛选不同起报时次预报时段可将模型预报误差控制在±3℃以内,且预报早高峰温度好于晚高峰,白天好于夜间,晴天好于其他天气类型。     

基于METRo模型的冬奥高速公路示范站路面温度临近预报方法

基于METRo模型探讨2022年北京-张家口冬季奥运会高速公路示范站(北京回龙观站)的冬季路面温度临近预报方法,采用大量样本数据迭代训练拟合的人为热参数作为前置参数加入METRo模型,拟减小METRo模型的系统性误差和人类生产生活对路面温度预报的影响。结果表明:(1)引入人为热参数后,METRo模型的模拟能力明显提升,特别是夜间,路面温度预报的均方根误差可控制在1℃左右;(2)人为热对路面温度有白天负反馈、夜间正反馈的作用;(3)白天路面温度受气象模式对辐射预报能力局限性的影响,仍存在一定误差。总体上,使用前置人为热参数的METRo模型对冬奥高速公路示范站进行路面温度尤其是路面低温的模拟是可行的,能够支撑冬季高速公路路面温度及路面结冰的预报预警能力。     

河南地区降水量和云量与地面太阳短波辐射的关系

对河南省2009~2018年地面太阳短波辐射量与降水量和云量的关系进行了分析,结果表明,地面太阳短波辐射量与降水量、云量具有显著的负相关关系,但在不同季节其相关关系差异较大。为了定量表征三者之间的关系,基于多年再分析资料,利用降水量和云量与地面太阳短波辐射量的关系对日辐射量进行拟合,并对拟合后的日辐射量进行检验。验证结果显示,此考虑季节性变化的回归模型对河南省地面太阳短波辐射有较好的拟合能力,可以作为基于气象预报的日辐射量短期变化评估基础,为光伏发电量的短期预报提供参考。     

WRF模式模拟的地表短波辐射与实况对比分析

利用中尺度数值模式WRFV3对2009年1、4、8和10月进行了约4个月的逐日（0～36小时）到达地表短波辐射模拟,将输出结果转换成逐小时太阳总辐射,并以武汉站为例,与地表实测逐小时总辐射值进行对比分析。结果表明：（1）模拟结果与观测结果有较好的对应关系,4个月的日间模拟和观测值的相关系数均在0.8以上,均通过了置信度0.01的显著性检验。（2）日间各时刻模拟值与实况相比,平均预报误差早晚小,中午大;平均绝对误差变化趋势与平均预报误差相同,平均绝对百分比误差则一般早晚大,09—15时较小且变化幅度小,可信度高于其他时刻。（3）WRFV3模式对太阳总辐射,在各种气象条件下均有一定预报能力,尤其以晴天表现最佳。距直接使用模式输出的地表短波辐射结果作为光伏发电系统初值用于发电量预报还有一些误差,可以尝试采用误差订正等方法修订,提高数值预报结果的可用性。     

包头市不同路面温度变化特征及预报模型研究

利用包头试验场2016年12月—2018年12月沥青、水泥、地砖、砂石路面温度、气温观测和同期气象站实况资料,统计分析了不同季节、不同天气状况下各种路面温度和气温的日变化特征,以及不同路面温度与气象因子的关系,采用逐步回归统计方法建立了不同季节不同路面温度预报模型并进行检验。结果表明,不同路面温度的日变化与季节和天空状况有密切关系,路面温度与平均气温、最高气温、最低气温呈显著正相关;与相对湿度呈负相关。基于不同路面温度预报方程的检验结果得出,预报准确率在82%～94%,相关系数在0.86～0.96,模型应用于路面温度预报业务。     

BJ-RUC产品在小区供暖供回水温度预报的应用研究

利用气象部门快速更新的BJ-RUC(Beijing-Rapid UpdateCycle)数值预报系统获得的24 h逐时的室外温度预报资料,应用能量平衡原理,建立建筑物热损失方程和供热量方程,从而推导出室外温度和室内温度、供水、回水温度的预报模型。用此模型对2010年3月1—15日期间的供、回水温度进行预报模拟,与北京市海园物业供热单位实况值进行对比分析。检验结果表明,该模型模拟的室内温度与设计要求的室内温度(20℃)之间的均方根误差为0.25℃,海园物业室内温度监测点数值与20℃之间的均方根误差为1.53℃。模拟的供、回水温度与海园物业监测点供水温度的均方根误差分别为3.69℃和3.80℃。     

陕西省高速公路路面温度特征及预报模型

利用2013年8月至2017年12月陕西高速公路交通气象站的路面温度、气温、相对湿度、风速等资料和全球大气再分析资料云量数据,分析四季不同天空状况下路面温度的分布特征,研究路面温度与气象因子的关系,建立多元回归方程。结果表明:四季路面温度有明显的日变化规律,雪后,00:00—08:00为路面结冰较易发生时段;气温是影响路面温度变化的最重要因子之一;对比路面温度实测值与预报值,回归模型对冬季路面最低温度的拟合效果较优,相关系数在0.94以上,标准差小于1,误差在±2℃的频率为98%。此外,模型对路面0℃低温预报水平较高。     

Evaluation of the Urban Tile in MOSES using Surface Energy Balance Observations

The UK Met Office has introduced a new scheme for its urban tile in MOSES 2.2 (Met Office Surface Exchange Scheme version 2.2), which is currently implemented within the operational Met Office weather forecasting model. Here, the performance of the urban tile is evaluated in two urban areas: the historic core of downtown Mexico City and a light industrial site in Vancouver, Canada. The sites differ in terms of building structures and mean building heights. In both cases vegetation cover is less than 5%. The evaluation is based on surface energy balance flux measurements conducted at approximately the blending height, which is the location where the surface scheme passes flux data into the atmospheric model. At both sites, MOSES 2.2 correctly simulates the net radiation, but there are discrepancies in the partitioning of turbulent and storage heat fluxes between predicted and observed values. Of the turbulent fluxes, latent heat fluxes were underpredicted by about one order of magnitude. Multiple model runs revealed MOSES 2.2 to be sensitive to changes in the canopy heat storage and in the ratio between the aerodynamic roughness length and that for heat transfer (temperature). Model performance was optimum with heat capacity values smaller than those generally considered for these sites. The results suggest that the current scheme is probably too simple, and that improvements may be obtained by increasing the complexity of the model.     

Increased heat fluxes near a forest edge

Summary ?Observations of sensible and latent heat flux above forest downwind of a forest edge show these fluxes to be larger than the available energy over the forest. The enhancement averages to 56 W m⁻², or 16% of the net radiation, at fetches less than 400 m, equivalent to fetch to height ratios less than 15. The enhancement of turbulent energy fluxes is explained by advection and increases with the difference in temperature and humidity of the air over the upwind area as compared to the forest. The relatively high temperature and humidity of the upwind air are not caused by high surface heat fluxes, but are explained by the relatively low aerodynamic roughness of the upwind surface. Although the heat fluxes over forest are enhanced, the momentum fluxes are almost adjusted to the underlying forest. The different behaviour of heat and momentum fluxes is explained by absorption of momentum by pressure gradients near the forest edge. It is concluded that fetch requirements to obtain accurate surface fluxes from atmospheric observations need to be more stringent for scalar fluxes as compared to momentum fluxes. Received November 23, 2001; accepted May 13, 2002     

基于INCA和METRo的江苏省路面高温精细化预报

使用INCA（Integrated Nowcasting through Comprehensive Analysis）多源资料融合分析和短临外推预报系统的预报结果作为气象强迫场,驱动一路面温度理论预报模型（Model of the Environment and Temperature of Roads,METRo）,开展江苏省高速公路夏季路面高温预报试验,并使用公路沿线逐小时的路面温度观测资料对预报结果进行检验。结果表明:该预报方法能够较好地预报出高速公路沿线日最高路面温度的逐日变化趋势,以及日最高路面温度的大范围空间分布特征。平均日最高路面温度预报绝对偏差为4.1℃,平均相对偏差为10.8%。其中,日最高路面温度预报绝对偏差在5℃以内的站次占总数的64.5%,相对偏差在15%以内的站次占总数的74.6%,比常规业务预报方法分别提高了23.1%和25.3%。但该预报方法对较小的温度波动以及局地性较强的极端温度分布特征的预报技巧还需进一步提高。     

Comparison of in-situ measured ground heat fluxes within a heteorogeneous urban ballast layer

Summary This study concentrates on measurements of ground heat fluxes within a porous urban ballast layer that were conducted from June to September 2002 at the goods station in Osnabrück, Germany. To account for the limitation of accurately installing sensors within the heterogeneous and porous ballast bulk, the heat fluxes were calculated from four different methods to compare their variability, dynamics and shortcomings. Ground heat fluxes were gathered from 1) a heat flux plate with the inclusion of heat storage between the soil surface and the heat flux plate, 2) temperature gradient measurements with correction for heat storage, 3) temperature gradient measurements with a modelled surface temperature and a laboratory derived thermal conductivity, 4) as residual from the surface energy balance equation. The results show a distinct deviation of the four methods for absolute values of the ground heat flux as well as for temporal dynamics on the diurnal cycle. As indicated by the temporal dynamics of the ground heat flux times series and a simple error analysis of the four methods, the most plausible estimates for an urban application in a heterogeneous ballast layer were obtained by temperature gradient measurements between the surface and −0.05 m. Overall, the results indicate that accurate ground heat flux measurements in urban applications still prove difficult to acquire.     

北方地区小麦蚜虫气象适宜度预报模型构建

根据1958—2015年我国北方地区8个主产省（市）小麦蚜虫分省发生面积和发生程度资料、1958—2015年601个气象站点相应逐日气象资料和农业气象站小麦发育期资料,采用相关分析、主成分分析和逐步回归等方法,并利用相关系数法进行因子普查,结合小麦蚜虫适宜生理气象指标和华北、黄淮小麦生育期规律,筛选影响小麦蚜虫年发生程度的关键气象因子,构建分区域的小麦蚜虫气象适宜度预报模型,并将气象适宜度指数划分为非常适宜、适宜、较适宜、不适宜4个等级,以反映气象条件对小麦蚜虫发生发展的适宜程度。结果表明:筛选出影响华北小麦蚜虫年发生程度的8个关键气象因子,影响黄淮小麦蚜虫年发生程度的6个关键气象因子。建立的华北、黄淮模型回代检验等级准确率分别为91.2%,93.1%,2016—2018年3年外推预报平均准确率均在75%以上;利用黄淮模型反演苏皖两省2016—2018年小麦蚜虫发生等级、异地检验3年预报效果均较理想。模型适用于从气象角度对华北、黄淮及江淮地区小麦蚜虫发生等级进行监测和预报。     

应用E-ε湍流动能闭合湖泊热力学过程模型对东太湖湖-气交换的模拟

采用考虑沉水植物影响的E-ε湍流动能闭合湖泊热力学过程模型,模拟2013年8月东太湖湖-气交换过程,并利用太湖的站点观测数据对模型进行了验证。太湖水温的模拟值与观测值吻合较好,模型计算的各层水温与观测值相比,均方根误差均未超过1℃。同时模型也较好地模拟出太湖表面感热通量和潜热通量,潜热通量的模拟值与观测值的标准差为54.7 W/m2。由于湖水较浅,太湖的水温层结会明显受到天气状况的影响。晴朗小风条件下的湖水呈现显著的热分层现象,当风速为0.8 m/s,高层和底层的温差达到7.9℃。大风天气条件驱动较强的水体湍流混合,水温的热分层消失,风速为12 m/s,湖泊上层与底层的水温差仅0.12℃。此外,模拟结果较好地呈现出了东太湖沉水植物的存在通过增大湖体消光系数,减小到达湖体内部的热量,并增加对湖水的阻力,影响湖体中湍流动能的分布,并进而影响湖水温度的分布。综上所述,该模型能够较好地模拟出浅水大湖湖-气交换的过程。      

Sensitivity of the thermohaline circulation in coupled oceanic GCM — atmospheric EBM experiments

We analyze the sensitivity of the oceanic thermohaline circulation (THC) regarding perturbations in fresh water flux for a range of coupled oceanic general circulation — atmospheric energy balance models. The energy balance model (EBM) predicts surface air temperature and fresh water flux and contains the feedbacks due to meridional transports of sensible and latent heat. In the coupled system we examine a negative perturbation in run-off into the southern ocean and analyze the role of changed atmospheric heat transports and fresh water flux. With mixed boundary conditions (fixed air temperature and fixed surface fresh water fluxes) the response is characterized by a completely different oceanic heat transport than in the reference case. On the other hand, the surface heat flux remains roughly constant when the air temperature can adjust in a model where no anomalous atmospheric transports are allowed. This gives an artificially stable system with nearly unchanged oceanic heat transport. However, if meridional heat transports in the atmosphere are included, the sensitivity of the system lies between the two extreme cases. We find that changes in fresh water flux are unimportant for the THC in the coupled system.     

Temporal variations in heat fluxes over a central European city centre

Summary Energy fluxes have been measured over an area near the centre of the city of Łódź, Poland, since November 2000. The site was selected because the building style (surface cover and morphology) is typical of European cities, yet distinct from the majority of cities where energy balance observations have been studied thus far. The multi-year dataset permits consideration of temporal changes in energy balance partitioning over a wide range of seasonal and synoptic conditions and of the role of heat storage and anthropogenic fluxes in the energy balance. Partitioning of net radiation into the turbulent fluxes is consistent in the two years, with the largest differences occurring due to differing precipitation. The monthly ensemble diurnal cycles of the turbulent fluxes over the two years are similar. The largest differences occur during the July–September period, and are attributable to greater net radiation and lower rainfall in 2002. The latent heat flux accounts for approximately 40% of the turbulent heat transfer on an annual basis. The average daily daytime Bowen ratio and its variability are slightly reduced during the summer (growing) season. Anthropogenic heat is a significant input to the urban energy balance in the winter. The fluxes observed in this study are consistent with results from other urban sites.     

根系吸水过程参数化方案对青藏高原陆面过程模拟的影响研究

根系吸水过程对地表能量平衡和水循环起着重要作用，目前不同的根系吸水过程参数化方案对青藏高原陆面过程模拟的影响尚不明确，探讨相关参数化方案的影响，可以为今后建立陆面过程模式根系参数化方案提供参考。本文利用2010年6月1日至9月30日青藏高原玛曲站的观测资料作为大气强迫资料，驱动BCC_AVIM模式（北京气候中心陆面模式）引入不同的根系吸水过程参数化方案，对玛曲站2010年6月1日至9月30日时段感热通量、潜热通量、土壤温度、土壤含水量等要素进行数值模拟，分析根系吸水过程参数化方案对青藏高原地区陆面过程的影响。模式中有关根系吸水过程的参数化方案主要分为根分布模型和土壤水分对根系有效性函数两类，根分布模型用Jackson方案、Schenk方案替换，土壤水分对根系有效性函数用Li方案、LSM1.0方案、CLM4.5方案替换。对比结果表明:不同的根系吸水过程参数化方案对土壤温度、土壤含水量的模拟影响较小，对感热通量、潜热通量模拟影响较大，尤其对冠层蒸腾量模拟差异显著，相关参数化方案的变动直接影响冠层蒸腾量。两类方案模拟的差异受降水的影响，在多雨期，根分布对比方案与原模式方案模拟的感热、潜热通量间存在较大差异；在少雨期，土壤水分对根系有效性函数对比方案与原模式方案模拟的感热、潜热通量间存在较大差异。