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飞机积冰气象条件研究进展 总被引：1，自引：0，他引：1
飞机积冰的直接影响气象因子包括大气温度、云中过冷水含量、过冷水滴大小。飞机积冰气象条件的研究对于飞行安全保障、飞机适航验证、人工影响天气等方面具有重要意义。近年来在飞机积冰气象条件研究方面取得了很大进展,文章对飞机积冰气象条件的外场观测、天气系统、监测识别、预报方法、气候分布等方面进展进行了简要综述,并对有关问题进行了讨论。飞机探测结果表明,过冷水时空分布具有明显不均匀性,国外以大量飞机积冰观测试验为基础统计分析了积冰环境,并制定了用于飞机积冰适航验证的一系列标准。产生飞机积冰的主要天气系统是锋面、高空槽线和切变线,冻雨往往产生强积冰。综合多源遥感数据各自的优势信息,建立飞机积冰区域识别技术是主要趋势。具有对云水显式预报能力的中尺度模式为预报飞机积冰提供了更好的工具。同时将多种监测数据、模式数据相融合的实时积冰潜势系统是新的发展方向。 相似文献
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Recent Progress in Atmospheric Observation Research in China 总被引：2，自引：0，他引：2
Recent progress in atmospheric observation techniques, observational systems and their application in China are reviewed. According to different observational platforms, the review is presented in three sections, i.e., satellite remote sensing （SRS）, ground-based observation technologies and applications, and aircraft/balloon measurements. The section ＂satellite remote sensing＂ presents advances in SRS techniques, SRS of clouds and aerosols, and SRS of trace gases and temperature/moisture profiles. The section ＂groundbased observation technologies and applications＂ focuses on research such as lidar systems and applications, sun/sky radiometer and broadband radiation observations, weather radar and wind profilers, GPS measurements, and some new concept systems. The section ＂aircraft/balloon measurements＂ presents some newly developed aircraft- and balloon-based sounding techniques. 相似文献
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Theoretical and Applied Climatology - This paper describes an intercomparison experiment between airborne measurement systems, radiosondes and a Laser-Doppler-Anemometer (LDA). The aircraft are a... 相似文献
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Comparison of Boundary-Layer Profiles and Layer Detection by AMDAR and WTR/RASS at Frankfurt Airport
At Frankfurt airport (EDDF) vertical soundings of the lower atmosphere from two independent sources are available. One of
them is a wind and temperature profiler (wind temperature radar and radio acoustic sounding system, WTR/RASS) located at the
western end of the main pair of runways. The second source is aircraft meteorological data relay (AMDAR), i.e. measurements
operationally collected by approaching and departing aircraft. Together, both offer a rare opportunity to compare the performance
of these widely used systems. We use 1 year of continuous data to calculate systematic temperature and wind vector differences
between both measurement systems. The differences show a clear season-dependent structure in conjunction with typical inversion
heights. Possible causes for this behaviour are discussed. Second, we compare the ability of both systems to identify inversion
and wind-shear layers above the airport. AMDAR-detected layers are typically higher than wind profiler detections. The layer
base is usually detected with more agreement than the top. The mutual probability of detection of inversions is found to be
mostly between 40 and 60%. 相似文献
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B. A. Ridley M. A. Avery J. V. Plant S. A. Vay D. D. Montzka A. J. Weinheimer D. J. Knapp J. E. Dye E. C. Richard 《Journal of Atmospheric Chemistry》2006,54(1):1-20
On flights of a P3-B turboprop and a WB-57F jet aircraft within thunderstorm systems, short term spikes (1–2 sec or less in duration) in NO and O3 were recorded and are attributed to hot or cold discharges occurring on the aircraft fuselage or air sampling inlets. One such spike of only ∼300 msec duration reached 325 ppbv of NO on the flight of the jet aircraft while at 13.8 km altitude. In a lightning flash to the P3-B aircraft, production of NO (expected) and NO2 (unexpected) were directly observed. The NO production was ∼ 1.7 x 1022 molecules/m of flash length. In the P3-B flight at 5.5 km altitude and over a distance of ∼ 275 km within a highly electrically active thunderstorm complex in the equatorial central Pacific Ocean, there was no evidence of production of O3 or CO by lightning flashes or by any type of hot or cold discharge involved in the development of free-air lightning flashes. 相似文献
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Aircraft and ground-based measurements made during the1995 Australian OASIS field campaign are compared. The aircraft data were recorded during low-level flightsat 6 m above ground level and grid flights at altitudes of between 15 and 65 m, allin unstable atmospheric conditions. The low-level flights revealed an inadequate temperaturesensor response time, a correction for which was determined from subsequent work ina wind tunnel. Aircraft and ground-based measurements of mean wind speed, wind directionand air temperature agree to within 0.2 m s-1, 4° and 0.9 °C respectively.Comparisons between aircraft and ground-based observations of the standarddeviations of vertical velocity, horizontal wind speed, air temperature and specifichumidity have slopes of 0.96, 0.97, 0.92 and 0.99 respectively but the observed scatter isroughly twice the random error expected due to the averaging length of the aircraft data andthe averaging period of the ground-based data. For the low-level flights, the ground-basedand aircraft measurements of sensible and latent heat flux show mean differences of 27 and-25 W m-2 respectively, which reduce to 11 and -4 W m-2 respectivelywhen analysis of aircraft data is limited to areas immediately adjacent to the fluxtowers. For the flights at 15 to 65 m above ground level, the mean differences between theground-based and aircraft measurements of sensible and latent heat flux are -22 and-1 W m-2 respectively and these change to -1 and -7 W m-2 respectively oncethe effect of surface heterogeneity is included. Aircraft and ground-based measurementsof net radiation agree to within 6% at one ground-based site but differ by 20% at a second.Aircraft measurements of friction velocity at 6 m above the ground agree well withground-based data, but those from flights between 15 and 65 m above ground level do not.This is because at these heights the aircraft measurements provide the local shear stress,not the surface shear stress. Overall, the level of agreement allows confidence in the aircraftdata provided due care is taken of instrument response times and differences in thesurfaces sampled by aircraft and ground-based systems. 相似文献
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W. F. Dabberdt G. L. Frederick R. M. Hardesty W.-C. Lee K. Underwood 《Meteorology and Atmospheric Physics》2004,87(1-3):57-88
Summary Air quality forecasting and emergency response are receiving increasing emphasis in the US and elsewhere; both share similar but not identical needs for advanced meteorological observations. At the same time, there has been a steady increase in the performance characteristics of ground-based remote sensing systems as well as ground-based and airborne in situ measurement systems. The structure of the planetary boundary layer is summarized in the context of implications for transport and diffusion, along with the measurement requirements for dispersion modeling. We then review the current state-of-the-art of operational and quasi-operational measurement systems with a focus on boundary layer measurements. Measurement systems discussed include: meteorological radar, radar wind profilers, radio acoustic sounding systems, lidar, sodar, GPS receivers, microwave radiometers, radiosonde systems, commercial aircraft measurements, and traditional near-surface in situ sensors. 相似文献
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飞机积冰是影响飞行安全的重要危险天气,准确的积冰诊断对民航运行与安全具有重大意义,特别是对国产大飞机适航取证具有重要作用。本文参考改进的CIP(Current Icing Potential)指数,使用垂直速度和云中液态水含量对积冰潜势诊断指数进行优化得到SCIP(Simplified Current Icing Potential)指数,该指数直接基于大气层结资料给出较为准确地飞机积冰潜势,具有命中率高、实用性强的特点。用2021年2月28日至12月31日民航航空器报告对原CIP指数和SCIP指数进行对比验证评估,发现相比于原CIP指数,SCIP指数具有更优异的ROC曲线(Receiver Operating Characteristic Curve)和TSS评分(True Skill Score)。但是对于不同程度的积冰,原CIP指数和SCIP指数均表现出较一致诊断效果,表明SCIP指数对诊断飞机积冰潜势具有重要作用,但无法判断积冰强度。根据2020年3月16日陕西区域飞机结冰个例验证表明增加垂直速度和云中液态水含量的影响对飞机积冰的描述更加细致,对提升积冰潜势诊断效果具有重要意义... 相似文献
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Phase Two of the Integrative Monsoon Frontal Rainfall Experiment (IMFRE-II) over the Middle and Lower Reaches of the Yangtze River in 2020 总被引：1，自引：0，他引：1
Phase Two of the Integrative Monsoon Frontal Rainfall Experiment(IMFRE-II)was conducted over the middle and lower reaches of the Yangtze River during the period 16 June to 19 July 2020.This paper provides a brief overview of the IMFRE-II field campaign,including the multiple ground-based remote sensors,aircraft probes,and their corresponding measurements during the 2020 mei-yu period,as well as how to use these numerous datasets to answer scientific questions.The highlights of IMFRE-II are:(1)to the best of our knowledge,IMFRE-II is the first field campaign in China to use ground-based,airborne,and spaceborne platforms to conduct comprehensive observations over the middle and lower reaches of the Yangtze River;and(2)seven aircraft flights were successfully carried out,and the spectra of ice particles,cloud droplets,and raindrops at different altitudes were obtained.These in-situ measurements will provide a“cloud truth”to validate the ground-based and satellite-retrieved cloud and precipitation properties and quantitatively estimate their retrieval uncertainties.They are also crucial for the development of a warm(and/or cold)rain conceptual model in order to better understand the cloud-to-rain conversion and accretion processes in mei-yu precipitation events.Through an integrative analysis of ground-based,aircraft,and satellite observations and model simulations,we can significantly improve our cloud and precipitation retrieval algorithms,investigate the microphysical properties of cloud and precipitation,understand in-depth the formation and dissipation mechanisms of mei-yu frontal systems,and improve cloud microphysics parameterization schemes and model simulations. 相似文献
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飞机积冰云微物理特征分析及监测技术研究 总被引：2，自引：2，他引：0
利用7个架次有积冰报告的飞机探测资料,对积冰云的微物理特征进行了分析,详细描述了云中相态组成、液水含量、中值体积直径和过冷大滴浓度特征。介绍了基于卫星、数值模式输出和地面观测资料的飞机积冰潜势监测技术,在与20个飞机探测积冰报告对比中,积冰监测可识别率为90%,并应用飞机积冰潜势监测技术具体分析了2010年10月26日的积冰个例。最后介绍了基于积冰潜势监测技术的飞机积冰监测系统,该系统能够支持水平分辨率为20 km、垂直分辨率为25 hPa、时间分辨率为1 h的飞机积冰潜势产品的运算和显示,该系统可为实际业务提供参考。 相似文献
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甘肃中部地区飞机积冰的气象条件分析 总被引：1，自引：0，他引：1
利用3a空中观测资料和机载仪器采集资料分析了影响飞机积冰的气象条件,总结了飞机积冰的一般规律。分析结果表明：飞机积冰在水汽充沛地域发生较多;通常飞机积冰形成于温度低于0℃的云中,出现积冰的温度范围在0～-11℃,而出现较强积冰的温度范围在-1--18℃;云中过冷水含量越大,积冰强度也越大。 相似文献
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The mei-yu season,typically occurring from mid-June to mid-July,on average,contributes to 32%of the annual precipitation over the Yangtze-Huai River Valley(YHRV)and represents one of the three heavy-rainfall periods in China.Here,we briefly review the large-scale background,synoptic pattern,moisture transport,and cloud and precipitation characteristics of the mei-yu frontal systems in the context of the ongoing Integrative Monsoon Frontal Rainfall Experiment(IMFRE)field campaign.Phase one of the campaign,IMFRE-I,was conducted from 10 June to 10 July 2018 in the middle reaches of the YHRV.Led by the Wuhan Institute of Heavy Rain(IHR)with primary support from the National Natural Science Foundation of China,IMFRE-I maximizes the use of our observational capacity enabled by a suite of ground-based and remote sensing instruments,most notably the IHR Mesoscale Heavy Rainfall Observing System(MHROS),including different wavelengths of radars,microwave radiometers,and disdrometers.The KA350(Shanxi King-Air)aircraft participating in the campaign is equipped with Ka-band cloud radar and different probes.The comprehensive datasets from both the MHROS and aircraft instruments are combined with available satellite observations and model simulations to answer the three scientific questions of IMFRE-I.Some highlights from a previously published special issue are included in this review,and we also briefly introduce the IMFRE-II field campaign,conducted during June-July 2020,where the focus was on the spatiotemporal evolutions of the mei-yu frontal systems over the middle and lower reaches of the YHRV. 相似文献
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Vertical turbulent transports of latent and sensible heat through the tropical marine boundary layer were measured with ship and airborne instruments in the GATE experimental area. The measurements from the two systems are compared for cases of simultaneous sampling in the same locations during undisturbed weather and during the wakes of convective disturbances. The paired average fluxes from the airborne eddy correlation measurements and the shipboard bulk aerodynamic measurements, for undisturbed weather, are related with correlation coefficients in the range of 0.6 to 0.9; the correlations depend primarily on stratifications of the aircraft data according to sampling altitude (15–153 m msl) and flight pattern relative to the mean wind. The agreement between the two types of measurements is best for ship data paired with aircraft samples from the lowest altitudes (15 and 30 m) and from alongwind rather than crosswind flights, as is appropriate since the stationary ships monitor the alongwind characteristics of the turbulence. The use of long (1–3 hr) versus short (10 min) ship samples did not significantly affect the comparability with the aircraft samples during undisturbed periods.The good baseline comparability demonstrated by the undisturbed-weather comparisons was applied to interpret the results from the wakes behind showers. Although these paired measurements were few, not only the sensible heat, but also the latent heat flux was shown to decrease substantially with altitude from 10 m to at least 150 m in the wakes, where the mixing was relatively intense. Variations in the fluxes were much greater at the higher level than nearer the sea surface. 相似文献
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We discuss the accuracy requirements for measuring mesoscale (roughly horizontal scales > 10 km or 5 to 10 times the planetary
boundary-layer (PBL) depth) fluxes in the convective PBL, and the ability of current research aircraft to achieve this accuracy.
We conclude that aircraft equipped with inertial nagivation systems capable of < 3 km hr−1 navigational accuracy are able to resolve mesoscale fluctuations in velocity, and thus variances and fluxes on the mesoscale.
We then discuss measurements of velocity and scalar spectra, and cospectra of vertical velocity with horizontal velocity components
and scalars, obtained from long flight legs with the National Center for Atmospheric Research Electra aircraft over the boreal
forest of Canada in summer during the BOreal Ecosystem-Atmosphere Study (BOREAS), over the tropical Pacific Ocean from the
Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE), and over the East China Sea during
wintertime cold-air outbreaks from the Air Mass Transformation Experiment (AMTEX). Each of these studies has somewhat different
forcings and boundary conditions, so we can compare their consequences on the spectra and cospectra. On average, we found
no significant scalar or momentum fluxes for horizontal scales > 10 km. We also develop a simple model based on observed
thermal structure to explain the phase angle between vertical velocity and the along-wind horizontal velocity as a function
of height, which shows good agreement with the observed phase angle in AMTEX.
The National Center for Atmospheric Research is sponsored by the National Science Foundation. 相似文献
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Summary This paper provides a theoretical calibration of Optical Array Probes (OAP) mounted on a given aircraft, in order to take
into account the aerodynamic influence of the entire aircraft on the measurements obtained. The measured parameters are corrected
through the computation of the air flow-field around the entire aircraft carrying the probes, for different flight conditions,
in order to obtain the corresponding undisturbed values. These undisturbed values have been compared to the microphysical
ones computed by an atmospheric model, the Regional Atmospheric Modeling System (RAMS). It was found that the removal of the
disturbances made by the aircraft on the atmospheric conditions is feasible and provides data that compare much better to
the model results. It is suggested that such kind of airborne data corrections may be performed in order to improve the quality
of the observations if the aircraft and probe geometries are known. Further information regarding the best location of the
probes on the considered aircraft is also obtained. 相似文献
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Blacklist methods are used in the CMA Global Forecasting System (CMA-GFS) to improve the application of aircraft temperature data to numerical weather prediction in the Northern Hemisphere and the tropics. In this paper, the ERA5 re-analysis data are used to analyze aircraft temperature observation errors of each aircraft and a blacklist is established using pre-quality controls and threshold methods. The blacklist-filtered and blacklisted aircraft temperature data are then applied to the four-dimensional variational assimilation system, respectively, and an assimilation cycle forecast for the period from September 1 to 30, 2019 is carried out. The results show an uneven distribution in the global aircraft blacklist data. After the application of the blacklist methods, the RMSE of geopotential height and temperature analysis field decrease in the vertical direction by a maximum of ~ 1.5 gpm at 200 hPa and ~ 0.15 K at 250 hPa, respectively. Overall, the blacklist methods of aircraft temperature data improve the analysis and forecast in the CMA-GFS. 相似文献
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设计并实现人工影响天气飞机作业实时监测移动应用系统（TEAM）,对飞机作业实时监测并可视化与共享,以解决飞机作业监测中作业信息采集渠道多样、标准不统一、共享范围小、飞机内外场交流渠道不畅等业务问题。TEAM基于人工影响天气飞机作业实时监测的移动应用平台框架（RMPF-WMA）构建并在移动终端上实现。该框架包括海事卫星、北斗卫星双链路传输、安全加固体系和分层策略,可作为数据和移动终端技术实现的标准化解决方案。TEAM基于HTML5混合开发模式与Ionic/Angular JS开发,提高开发效率和终端运行性能。TEAM实时可视化显示飞机准备情况、轨迹、播撒动态以及飞行简报、通知,提升飞机作业各环节沟通效率和共享覆盖度。全国人工影响天气作业飞机中,TEAM可实时监测并实现信息共享的飞机占总数的80%以上,应用于东北、华北、西北、西南、中部等多个区域日常飞机作业监测和重大应急服务一线指挥。移动应用程序响应迅速,运行稳定,作业监测和可视化效果良好。 相似文献