U.S_Standard_Atmosphere(1976)美国标准大气(1976)

1、资料和计算丰富、可靠的气象观测资料是研究和了解大气环流及气候特征的最重要的基础。

正是由于它们，才大大加深和扩大了我们对大气和气候运动本身的认识，并为理论研究和数值模拟提供了重要素材和基本保证。

没有这些宝贵的资料作为基础，任何关于大气或气候的研究都只能停留在空中楼阁亦或海市蜃楼的阶段。

虽然气象观测可以追溯到千年以前，但显然由于条件、认识、技术手段和科学发展水平的限制，在早期只是对发生在某些局部区域的大气中某些特殊天气现象的零星观测，还算不上是对大气环流的从地面到高空、从区域到全球、从单一到综合、从特殊到一般、从里到外、由外及里、从下到上、由上至下、从离散到连续的全方位、全视角的、系统的三维观测。

近半个多世纪以来，随着科学技术的迅速发展、监测手段的日益先进、社会需求的不断增加、国际协作的日渐密切，上述状况有了本质的改变。

各种新技术如气象雷达、气象卫星、红外及微波遥感、高速电子计算机等在气象观测中的广泛应用，使得气象观测水平有了史无前例的发展，观测的种类和质量有了前所未有的提高。

加之，由于人类本身生存和发展的需要，使得气象观测项目和种类大大丰富起来；由于国际间广泛紧密的合作，使得观测资料的协调度和统一性也大大提高了。

目前，已经形成了可同时监测全球天气情况的气象观测系统和气象通讯系统。

特别是，1991年美国国家环境预报中心（NCEP）和美国国家大气科学研究中心（NCAR）联手实施的全球再分析计划（NCEP/NCAR Global Reanalysis Project），把全球观测资料的质量提高到一个新的水平。

该计划在全球范围内，通过世界各国及各主要科研机构和业务部门，把能搜集到的资料包括地面观测资料、高空探测资料、航舶资料、卫星遥感资料、雷达资料、飞机资料、气球资料，浮标资料以及其它观测资料等统一进行编码、详细的订正预处理和复杂的质量控制，并用一个较完善的同化系统统一进行资料同化，使得观测资料的统一性、协调性、可靠性、完善性、代表性都有了显著的提高，引起了国际大气科学界的极大关注和反响。

INTRODUCTIONThe average person sends approximately 90% of their time indoors. Studies haveindicated that indoor air is often dirtier and/or contains higher levels of contaminants than outdoor air. Because of this and increased awareness regarding poor indoor air quality (IAQ), it is not surprising that the number of reported employee complaints of discomfort and illness in non-industrial workplaces is increasing.WHEN DID POOR INDOOR AIR QUALITY BECOME A PROBLEM?Beginning in the mid-1970s, IAQ complaints increased for two reasons. The main reason was the impact of the energy crisis. To reduce heating and cooling costs, buildings were made “airtight” with insulation and sealed windows. In addition, the amount of outside air introduced into buildings was reduced. The second reason is that more chemical-containing products,office supplies, equipment, and pesticides have been introduced into the office environment increasing employee exposure. Thesechanges created IAQ health problems known as Sick Building Syndrome (SBS) or Building-Related Illnesses (BRI).WHAT IS SICK BUILDINGSYNDROME?A workplace is characterized with SBS when a substantial number of building occupants experience health and comfort problems that can be related to working indoors. Additionally,Richard J. Codey Acting GovernorINDOOR AIR QUALITYPublic Employees Occupational Safety andHealth ProgramNovember, 2004the reported symptoms do not fit the pattern of any particular illness, are difficult to trace to any specific source, and relief from thesesymptoms occurs upon leaving the building.WHAT ARE THE SYMPTOMS OF SICKBUILDING SYNDROME?Employee symptoms of SBS may include headaches; eye, nose, and throat irritation; dry or itchy skin; fatigue; dizziness; nausea; and loss of concentration.WHAT ARE BUILDING-RELATEDILLNESSES?A workplace is characterized with BRI when a relatively small number of employees experience health problems. Symptomsassociated with BRI are generally different from those associated with SBS and are often accompanied by physical signs that are identified by a physician and/or laboratoryfindings. Relief from the illness may not occur upon leaving the building. BRI are caused by microbial contamination and/or specificchemical exposures that can result in allergic and/or infectious responses. Microbialcontamiantion occurs when viruses, bacteria,or molds accumulate in areas such as heating, ventilation, and air conditioning(HVAC) systems, water-damaged ceiling tiles and carpets, hot water heaters, andhumidifiers. Chemical exposures can be generated from specific sources within the workplace, such as formaldehyde emitted from newly installed carpets.WHAT ARE THE SYMPTOMS OFBUILDING-RELATED ILLNESSES?Employee symptoms of BRI may include eye, nose, throat, and upper respiratory irritation; skin irritation or rashes; chills; fever; cough; chest tightness; congestion; sneezing; runny nose; muscle aches; and pneumonia. Examples of BRI include asthma; hypersensitivity pneumonitis; multiple chemical sensitivity; and Legionnaires’ Disease.WHAT ARE THE SPECIFIC CAUSESOF SBS AND BRI?The IAQ problems that cause SBS and/or BRI may include:Lack of fresh air;If insufficient fresh air is introduced intooccupied spaces, the air becomes stagnant and odors and contaminants accumulate.Lack of fresh air in occupied areas is thenumber one cause of SBS.Poorly maintained or operated ventilation systems;Mechanial ventilation systems must beproperly maintained and operated based on the original design or prescribed procedures.If these systems are neglected, their ability to provide adequate IAQ decreases. Oneproblem associated with poorly maintainedsystems is missing, overloaded, or inefficient filters. This can cause higher levels of dust, pollen, and cigarette smoke to enteroccupied spaces. Another problem isclogged condensate drain pans and drainlines in HVAC systems, which allow water to accumulate. The accumulation of water can lead to microbial contamination. Poorlymaintained ventilation systems cancontribute to both SBS and BRI.Disruption of air circulation throughout the occupied spaces;The quality of the air depends on the effectiveness of air distribution. If the air circulation is disrupted, blocked, or otherwise does not reach occupied areas, it can become stagnant. File cabinets, bookshelves, stored boxes, dropped ceiling tiles, added office walls, cubicles, and partitions can block or divert the supply of air to occupied spaces.Poorly regulated temperature and relative humidity levels;If the temperature and/or relative humidity levels are too high or too low, employees may experience discomfort, loss of concentration, eye and throat irritation, dry skin, sinus headaches, nosebleeds, and the inability to wear contact lenses. If relative humidity levels are too high, microbial contamination can build up and can cause BRI.Indoor and outdoor sources of contamination;Chemical emissions can contribute to BRI and SBS. Chemical contaminants in an office environment either originate from indoor sources or are introduced from outdoor sources. Common sources include emissions from office machinery or photocopiers; cigarette smoke; insulation; pesticides; wood products; synthetic plastics; newly installed carpets; glues and adhesives; new furnishings; cleaning fluids; paints; solvents; boiler emissions; vehicle exhaust; roof renovations; and contaminated air from exhaust stacks. Contaminants found in indoor environments can also include radon; ozone; formaldehyde; volatile organic compounds; ammonia; carbon monoxide; particulates; nitrogen and sulfure oxides; and asbestos.2WHAT IS CONSIDEREDACCEPTABLE IAQ?The American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE) defines acceptable IAQ as:“air in which there are no knowncontaminants at harmful concentrations asdetermined by cognizant authorities and with which a substantial majority (80% or more) of the people exposed do not expressdissatisfaction.”WHAT CAN BE DONE IF THE AIRQUALITY IS UNACCEPTABLE?In order to understand and resolve IAQ problems and concerns, standard investigative procedures should be followed. Investigating IAQ complaints, however, can be very complicated due to employee concerns, unknown sources of contamination, and the complexities of buildings and their ventilation systems. The New Jersey Department of Health and Senior Services, Public Employees Occupational Safety and Health (PEOSH) Program recommends the following general investigative procedures:•Conduct employee interviews to obtainpertinent information regarding whatsymptoms are being experienced, howmany employees are affected, when theyare affected, where they work, what theydo, etc. - this information may identifypossible IAQ problems;•Review building operations andmaintenance procedures to determinewhen and what type of chemicals are being used during cleaning, floor waxing andstripping, painting, gluing, pesticidespraying, roofing operations, and renovation and construction activities, etc. - alsodetermine when deliveries occur, whichmay generate vehicle exhaust, or iffurniture, drapery, or office equipment hasbeen recently installed;•Conduct a walk-through inspection toevaluate possible sources that maycontribute to IAQ complaints;•Inspect the HVAC system, window airconditioners, office dehumidifiers, etc., inorder to determine if the systems areworking properly and are in good condition;•Review the building blueprints of theductwork and ventilation system todetermine if the system is adequatelydesigned;•Conduct air sampling, if necessary, todetermine if specific contaminants arepresent or if adequate fresh air is beingsupplied.HOW CAN IAQ PROBLEMS BE CORRECTED AND/OR PREVENTED? ENSURE ADEQUATE FRESH AIR SUPPLYThis has been shown to be the single most effective method for correcting and preventing IAQ problems and complaints. To ensure that adequate fresh air is supplied to occupied spaces, the following is recommended:• A preventive maintenance schedule mustbe developed and followed in accordancewith the manufacturer’s recommendationsor with accepted practice to ensure that theventilation systems are properly checked,maintained, and documented.•The preventive maintenance scheduleshould include the inspection andmaintenance of ventilation equipment and/or system, making sure that:−outdoor air supply dampers are opened as designed and remain unobstructed;3−fan belts are operating properly, in good condition, and replaced when necessary;−equipment parts are lubricated;−motors are properly functioning and in good operating condition;−diffusers are open and unobstructed for adequate air mixing;−the system is properly balanced;−filters are properly installed and replaced at specified intervals;−components that are damaged orinoperable are replaced or repaired as appropriate; and −condensate pans are properly draining and in good condition.•To achieve acceptable IAQ, outdoor airshould be adequately distributed to all office areas at a minimum rate of 20 cubic feet per minute (cfm) per person OR theconcentration of all known contaminants of concern be restricted to some specified acceptable levels as identified in ASHRAE’s “Ventiliation for Acceptable Indoor Air Quality” Standard.•To determine if the ventilation system iseffectively providing adequate fresh air,carbon dioxide (CO 2) levels should be measured; ASHRAE sets the standard(ASHRAE 62-1989) of 1000 ppm of CO 2 as the maximum recommended level for acceptable IAQ; CO 2, a byproduct of human respiration, is an indicator of the lack of fresh outdoor air and is not considered harmful at this level.•If possible, gauges should be installed toprovide information on air volumes delivered by supply and return fans.Maintenance staff should be trained to read the gauges and respond appropriately.• A sufficient supply of outside air should beprovided to all occupied spaces. Aninsufficient supply can cause the building to be at negative pressure, allowing untreated air and/or contaminants to infiltrate from outside. This can be determined byobserving the direction of air movement at windows and doors. In order to prevent this problem, the air supply and exhaust system must be properly balanced.•If the office layout is changed (e.g., byerecting partitions or new walls), ensure that adequate air flow and distribution is maintained.•Ventilation system filters should have amoderate efficiency rating (60% or more),as measured by the ASHRAE atmospheric dust spot test, and be of an extended surface type. To determine if the filters have the appropriate efficiency rating,check with the manufacturer. Prefilters (e.g., roll type) should be used before air passes through higher efficiency filters.•Avoid overcrowding of employees, andmake sure that the proper amount of outdoor air is provided based on the number of occupants.ELIMINATE OR CONTROL ALL KNOWN AND POTENTIAL SOURCES OF CONTAMINANTS,BOTH CHEMICAL AND MICROBIAL To Control Chemical Contamination:•Hazardous chemicals should be removed orsubstituted by less hazardous or non-hazardous chemicals, where possible.•Properly store all chemicals to minimizeexposure hazards.4•Use local exhaust ventilation to capture and remove contaminants generated by specific processes where appropriate. Ensure that local exhaust does not recirculate the contaminated air, but directly exhausts the contaminant outdoors. Check with the manufacturer of your office machines for guidance on ventilation requirements for their equipment.•Check to be sure that HVAC fresh air intakes or other building vents or openings are not located in close proximity to potential sources of contamination (e.g., places where motor vehicle emissions collect, downwind of exhausts, cooling towers). If necessary, raise stacks or relocate intakes or exhausts.•Isolate areas of renovation such as painting, carpet installation, etc., from occupied nonconstruction areas, through use of physical barriers and isolation of involved ventilation systems. If possible, perform this type of work in the evening or on weekends. Supplying the maximum amount of fresh air to these areas can assist in the dispersion of contaminant levels.•Use a licensed pesticide applicator for pesticide applications and follow their recommendations regarding appropriate ventilation controls.•Eliminate or reduce cigarette smoke. Smoking restrictions or designated smoking areas should be considered. The air from designated smoking areas must not be recirculated to non-smoking areas of the building.To Control Microbial Contamination:•Promptly detect and permanently repair all areas where water collection or leakage has occurred.•Maintain relative humidity at less than 60% in all occupied spaces and low air-velocity plenums. During the summer, cooling coils should be run at a low enough temperature to properly dehumidify conditioned air.•Check for, correct, and prevent further accumulation of stagnant water by maintaining proper drainage of drain pans under the cooling coils.•Due to dust or dirt accumulation ormoisture-related problems downstream ofheat exchange components (as in ductworkor plenum), additional filtration downstream may be necessary before air is introducedinto occupied areas.•Heat exchange components and drain pans should be accessible so maintenance personnel can easily inspect and clean them. Access panels or doors should be installed where needed.•Non-porous surfaces where moisture collection has promoted microbial growth(e.g., drain pans, cooling coils) should be properly cleaned and disinfected. Careshould be taken to ensure that these chemical cleaners are removed before ventilation systems are reactivated.•Porous building materials contaminated with microbial growth, such as carpets and ceiling tiles, must be replaced or disinfected to effectively eliminate contamination. Note that the American Conference of Governmental Industrial Hygienists (ACGIH) recommends that contaminated porous materials should be discarded.5RESOURCESAgencies and organizations that provide information on indoor air quality:New Jersey State Department of Health and Senior ServicesPEOSH Program, 7th FloorPO Box 360Trenton, NJ 08625-0360(609) 984-1863The PEOSH Program has an Indoor Air Quality Standard (N.J.A.C. 100-13) for public employees in New Jersey. The following publications, including a copy of the standard and additional information may be obtained from the above address or the PEOSH web site at www.nj/gov/health/eoh/peoshweb:*PEOSH “Indoor Air Quality Model Program”;*The American Industrial Hygiene Association’s Consultants’ List;*PEOSH Information Bulletin, “Mold in the Workplace, Prevention and Control”;*PEOSH Information Bulletin, “Renovation and Construction in Schools, Controlling Health and Safety Hazards”.U.S. Environmental Protection AgencyIndoor Air Quality Information ClearinghousePO Box 37133Washington, D.C. 20013-7133(800) 438-4318The United States Environmental Protection Agency (USEPA) has various publications on indoor air quality in the home, at schools, and in offices. The publications can be obtained from the address above or from the USEPA IAQ Information Clearinghouse web site at /iaq/iaqxline.html.American Conference of Governmental Industrial HygienistsKemper Woods Center1330 Kemper Meadow DriveCincinnati, OH 45240(513) 742-2020The American Conference of Governmental Industrial Hygienists (ACGIH) has a publication that addresses indoor bioaerosols issues, “Bioaerosols-Assessment and Control” Publication #3180. This publication can be obtained from the above address.American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.1791 Tullie Circle, NEAtlanta, GA 30329(404) 636-8400The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has two publications that are especially useful:*ASHRAE 62-2001 “Ventilation for Acceptable Indoor Air Quality” Standard, and*ASHRAE 55-1992 “Thermal Environmental Conditions for Human Occupancy” Standard.The publications can be obtained from the address above or from the ASHRAE web site at / store.ORIG PRINTED 11/94, REV 7/96, REV 10/046PEOSH PROGRAM READER RESPONSE CARDINDOOR AIR QUALITYDear Reader:Please take a few minutes to help us evaluate this publication. Please check the following:Check the category that best describes your position: manageremployeeeducatorsafety professional occupational health professional other (specify)researcherhealth care worker____________________________________Check the category that best describes your workplace:academiamunicipal government labor organization state government municipal utilities authorityother (specify)county government____________________________________Describe how thoroughly you read this publication: cover-to-coversections of interest only (specify)________________________ other (specify)________________________How will you use this information (check all that apply): change the work environment provide information not usedchange a procedure copy and distribute other (specify)assist in researchin training__________________change training curriculum__________________Which section did you find most useful?Which section did you find the least useful and why?Other occupational health topics on which you would like to see the PEOSH Program develop an information bulletin:Other comments and suggestions:C u t h e r e , f o l d i n t h i r d s , t a p e .November 2004NO POSTAGENECESSARYIF MAILEDIN THEUNITED STATESBUSINESS R EPL Y M AILFIRST CLASS PERMIT NO. 206TRENTON, NJPOSTAGE WILL BE PAID BY ADDRESSEESTATE OF NEW JERSEYDEPT OF HEALTH & SENIOR SERVICESPEOSH PROGRAMPO BOX 360TRENTON, NEW JERSEY 08625-9985。

MOD37 使用要点1 MODTRAN 文件1.1 输出文件输入Edit|Edit File 可查看运行 Modtran 产生的 ASCII 数据文件，在 usr 目录下有：Modout1、Modout2、Modout3Modout1 包含完整结果，波段平均透过率、辐亮度在最后一段。

INTEGRATED ABSORPTION FROM 625 TO 25000 CM-1 = 7170.3120 CM-1 AVERAGE TRANSMITTANCE = 0.7058INTEGRATED TOTAL RADIANCE = 2.602227E-03 WATT S CM-2 STER-1 (FROM 625 TO 25000 CM-1 )MINIMUM SPECTRAL RADIANCE = 0.000000E+00 WATT S CM-2 STER-1 / CM-1 AT 25000 CM-1MAXIMUM SPECTRAL RADIANCE = 1.168842E-05 WATT S CM-2 STER-1 / CM-1 AT 640 CM-1BOUNDARY TEMPERATURE = 0.000BOUNDARY EMISSIVITY = 1.0001.2 输入文件1.2.1 数据库文件文件名.LTN，包含Modtran 模型参数的输入文件和输出曲线打印方式的输入文件。

1.2.2 NOVAM 参数文件：文件名.NPR，6000 米以下海面气溶胶分布，较以前海洋气溶胶模型有明显改进。

1.2.3 滤波器函数文件：文件名.FLT滤波器函数可用于计算有效大气透过率或有效路径辐亮度。

滤波器函数包含辐射源的光谱特性和辐射测量仪器的光谱带通特性。

辐射源的光谱特性用黑体温度表示，仪器光谱特性取决于探测器光谱响应和光学元件光谱透过或反射特性，Modtran 可设置最多 80 个波数点的相对响应。

1.2.4 扫描函数文件：文件名.SCNModtran 内部计算样点的光谱间隔为 1cm-1，为降低输出数据的光谱分辨率，Modtran 提供了扫描功能，可将输出光谱数据与一个狭缝函数进行卷积运算。

美国国家海洋和大气管理局（NOAA）测量标准和要求一、外业测量手册外业测量手册为开展、处理以及生成海道测量成果提供了最佳做法及标准的作业程序。

这些指南有助于测量机构满足NOS海道测量规范和交付标准规定要求。

相关内容有：•系统准备和维护，包括软硬件系统年审以及定期的质量保证；•测量计划，包括安全考虑和项目说明；•数据获取，包括声纳、垂直和水平控制以及辅助数据；•数据分析，包括软件配置以及标准的处理步骤；•数据管理，包括数据存储及安全；•最终成果交付，包括数字和模拟数据以及项目报告。

手册为外业测量人员、技术人员、船长、管理人员以及所有海道测量外业从业人员提供了有价值的资源和参考文件。

NOS的数据信息并不支持商业公司或产品，该手册与专利产品、产品测试相关的信息是禁止用于宣传和广告目的的。

二、规范和交付《NOS海道测量规范与交付标准》对海道测量活动提出了详细明确的要求。

2014版包括了新的规范和对2013版本所做的修订。

要获取与NOS规范相一致的海道测量数据应使用目前最新的版本。

可通过网站上的咨询系统提出问题和建议，如果要获得《NOS海道测量规范与交付标准》更早的版本也可以通过邮件与NOS联系。

三、XML海道测量报告NOS开发了一套可扩展标记性语言（XML）架构用来生成并验证描述性报告（DR）。

《NOS海道测量规范与交付标准》要求NOAA外业部门和海道测量承包商按照XML格式提交描述性报告，这样可以转换成PDF文件从而便于阅读和打印。

XML有助于减少错误，是标准化产品。

用户可从国家地球物理数据中心获取XML报告。

这些报告的元数据也会自动存储到如海道测量元数据库等数据库中。

四、海道测量手册《海道测量手册》第4版（1976年）已经被《NOS海道测量规范与交付标准》和《外业测量手册》所取代。

目前仅作为参考资料提供。

五、IHO标准OCS作为IHO的一名活跃的成员，积极参与IHO委员会与工作组的标准制定与修订工作，并在相关业务中采用IHO 标准。

标准大气、标准等压面和标准大气压力这里所说的标准大气指人为规定的、特性随高度平均分布的大气。

我国在建立自己的标准大气之前，使用1976年美国标准大气，并以其30km以下部分作为国家标准。

海平面温度15.0℃，气压 P=1013.25hPa，大气密度：1.225kg/m3
地面至11km对流层的气温垂直递减率：0.65℃/100m,标准海平面加速度9.80665m/s2
11-20km平海面,温度不变
气温为–56.5℃ 气压价格P=226.32mb
海拔11—20公里的气温变化率：0.0℃/公里
海拔20—32公里的气温变化率：+1.0/公里
下表列出不同高度处标准大气的气温、气压值。

表中“gpm”为海拔米，其负号代表海拔以下。

1976年美国标准大气
1976年，美国正式颁布了《美国标准大气》（U.S. Standard Atmosphere），这
一标准大气模型被广泛应用于航空航天领域、气象学、大气物理学等领域。

该模型描述了大气的温度、压强、密度等参数随高度的变化规律，为工程设计、科学研究提供了重要的参考依据。

根据《美国标准大气》，大气温度随着海拔的增加而逐渐下降，这一规律是由
大气层的结构和组成所决定的。

在低空，大气温度随着高度的增加而逐渐下降，这一现象被称为温度递减。

然而在一定高度之后，大气温度开始上升，这是由于平流层中臭氧层的吸收紫外线所致。

了解大气温度的变化规律，有助于飞行器的设计和气象预测。

另外，《美国标准大气》还描述了大气压强和密度随高度的变化规律。

随着海
拔的增加，大气压强和密度均呈指数衰减。

这一规律对于航空器的性能评估和气象学研究至关重要。

了解大气压强和密度的变化规律，有助于飞行器的设计和飞行性能的评估。

除了描述大气参数随高度变化的规律外，《美国标准大气》还提供了大气层的
分层结构和组成。

大气层可分为对流层、平流层、中间层、热层和外层等不同层次，每个层次的特点和组成均有所不同。

了解大气层的结构和组成，有助于理解大气的物理过程和气候变化规律。

总的来说，《美国标准大气》为我们提供了一个简洁清晰的大气模型，帮助我
们更好地理解大气的物理特性和气候变化规律。

这一模型的应用不仅局限于航空航天领域，还涉及到气象学、大气物理学等多个领域。

通过对《美国标准大气》的研究和应用，我们可以更好地认识和利用大气，促进科学技术的发展和社会的进步。

我国、欧洲和美国空气过滤器标准的试验尘源和分级简介摘要：本文简单地对比了我国、欧洲和美国空气过滤器标准中关于试验尘源的异同，并介绍了三个标准体系中有关空气过滤器分级的情况。

关键词：空气过滤器试验尘源分级目前，在我国应用比较广的空气过滤器性能检测标准有：中华人民共和国国家质量监督检验检疫总局和中国国家标准化管理委员会发布的GB/T 14295-2008《空气过滤器》[1]、欧洲标准化委员会批准制定的EN 779:2002《一般通风用空气过滤器——过滤性能的测定》[2]、美国国家/美国采暖、制冷与空调工程师协会标准ANSI/ASHRAE52.1-1992《一般通风用空气净化装置试验方法——计重法和比色法》[3]和ANSI/ASHRAE52.2-2007《一般通风用空气净化装置计径效率方法》[4]。

本文简要介绍了上述三个标注体系中试验尘源和分级情况的异同。

1 试验尘源上述三个标准体系中，用于计重效率和容尘量试验的标准人工负荷尘都是由72%的道路尘、23%的炭黑和5%的短棉绒组成，其粒径分布和化学性质也基本一致。

但是用于计数效率试验的尘源有所不同，见表1。

表1 计数效率用尘源的比较2 分级2.1 GB/T 14295-2008按照GB/T 14295-2008的规定，除了粗效3和粗效4级别的空气过滤器是以标准人工尘计重效率作为级别划分的依据，其它级别的是以其初始计数效率作为空气过滤器分级的依据，其分级情况见表2。

表2 GB/T 14295-2008的空气过滤器分级情况2.2 EN 779:2002按照EN 779:2002的规定，粗效过滤器是以人工尘平均计重效率作为分级依据，中效过滤器则是以达到终阻力时整个容尘过程对0.4μm（0.3μm～0.5μm）粒子的平均效率作为分级依据，其分级情况见表3。

表3 EN 779:2002的空气过滤器分级情况2.3 ANSI/ASHRAE52.2-2007按照ANSI/ASHRAE52.2-2007的规定，粗效过滤器（MERV 1~4）是以人工尘平均计重效率作为分级依据，中效过滤器则是以达到终阻力时整个容尘过程对0.3μm～1.0μm、1.0μm～3.0μm和3.0μm～10.0μm三个粒径档粒子的平均效率的最低值作为分级依据，其分级情况见表4。

气象常用计算公式(总11页)--本页仅作为文档封面，使用时请直接删除即可----内页可以根据需求调整合适字体及大小--?1、资料和计算?丰富、可靠的气象观测资料是研究和了解大气环流及气候特征的最重要的基础。

正是由于它们，才大大加深和扩大了我们对大气和气候运动本身的认识，并为理论研究和数值模拟提供了重要素材和基本保证。

没有这些宝贵的资料作为基础，任何关于大气或气候的研究都只能停留在空中楼阁亦或海市蜃楼的阶段。

虽然气象观测可以追溯到千年以前，但显然由于条件、认识、技术手段和科学发展水平的限制，在早期只是对发生在某些局部区域的大气中某些特殊天气现象的零星观测，还算不上是对大气环流的从地面到高空、从区域到全球、从单一到综合、从特殊到一般、从里到外、由外及里、从下到上、由上至下、从离散到连续的全方位、全视角的、系统的三维观测。

近半个多世纪以来，随着科学技术的迅速发展、监测手段的日益先进、社会需求的不断增加、国际协作的日渐密切，上述状况有了本质的改变。

各种新技术如气象雷达、气象卫星、红外及微波遥感、高速电子计算机等在气象观测中的广泛应用，使得气象观测水平有了史无前例的发展，观测的种类和质量有了前所未有的提高。

加之，由于人类本身生存和发展的需要，使得气象观测项目和种类大大丰富起来；由于国际间广泛紧密的合作，使得观测资料的协调度和统一性也大大提高了。

目前，已经形成了可同时监测全球天气情况的气象观测系统和气象通讯系统。

特别是，1991年美国国家环境预报中心（NCEP）和美国国家大气科学研究中心（NCAR）联手实施的全球再分析计划（NCEP/NCAR Global Reanalysis Project），把全球观测资料的质量提高到一个新的水平。

该计划在全球范围内，通过世界各国及各主要科研机构和业务部门，把能搜集到的资料包括地面观测资料、高空探测资料、航舶资料、卫星遥感资料、雷达资料、飞机资料、气球资料，浮标资料以及其它观测资料等统一进行编码、详细的订正预处理和复杂的质量控制，并用一个较完善的同化系统统一进行资料同化，使得观测资料的统一性、协调性、可靠性、完善性、代表性都有了显着的提高，引起了国际大气科学界的极大关注和反响。

空⽓质量指数美国标准和中国标准差别⼀、什么是空⽓质量指数空⽓质量指数（Air Quality Index，简称AQI），是⼀个⽤来定量描述空⽓质量⽔平的数值。

AQI的取值范围位于0 – 500 之间。

环境空⽓污染物的种类有很多，常见的有⼆氧化硫(SO2)、⼆氧化氮(NO2)、⼀氧化碳(CO)、臭氧(O３)和悬浮颗粒物。

悬浮颗粒物中，直径⼩于等于10µm的称为PM10，直径⼩于等于2.5µm的称为PM2.5。

其中，现阶段对⼈们健康影响最⼤的要数PM2.5。

正是由于意识到PM2.5的严重危害，我国于2012年发布，将于2016年1⽉1⽇实施的国家标准GB 3095-2012《环境空⽓质量标准》(1)中，新增了对PM2.5的监测要求并规定了浓度限值。

环境监测部门每天发布的空⽓质量报告中，会包含各种污染物的浓度值，⽐如SO2浓度为20.5µg/m3、PM10浓度为150.8µg/m3、PM2.5浓度为130.7µg/m3等等。

但是，⼈们很难从这么多个抽象的浓度数据中判断出到底当前的空⽓质量处在什么⽔平。

于是就有⼈想出了⼀个办法，将各种不同污染物含量折算成⼀个统⼀的指数，这就是空⽓质量指数。

空⽓质量指数的值在不同的区间，就代表了不同的空⽓质量⽔平。

⽐如0 – 50之间，代表“良好”；51 – 100之间，代表“中等”；101 – 150之间，代表“对敏感⼈群不健康”……等等。

为了更直观起见，每个区间都有⼀个固定的颜⾊值与它对应：这样，只需要根据报告的AQI值，甚⾄只看颜⾊，即可直观判断空⽓质量⽔平。

⼆、我国空⽓质量指数是怎么算出来的空⽓质量指数是根据各种污染物的浓度值换算出来的。

要计算AQI，就需要事先确定各污染物在不同空⽓质量⽔平下的浓度限值。

利⽤这个公式和表中规定范围就可以算出污染物的分指数和AQI.当污染物浓度超出最⾼上限时，AQI的值最⾼也只能是500，因为在这之上的指数是不存在的。

标准大气美国1976标准大气是指在大气科学研究中常用的一种理想化大气模型，它是基于大量观测数据和理论分析得出的。

标准大气模型可以帮助科学家们更好地理解大气的结构和变化规律，也可以为航空航天等领域的工程设计提供重要参考。

美国1976年发布的标准大气模型是其中一种，下面将对其进行详细介绍。

美国1976年发布的标准大气模型是一种严格按照国际标准大气模型（ISA）进行修订的大气模型。

该模型在1976年由美国国家航空航天局（NASA）和美国大气研究中心（NCAR）联合发布，并被广泛应用于航空航天、气象学、大气物理学等领域。

该模型的主要特点包括对大气温度、压强、密度等参数的详细描述，以及对不同高度范围内大气物理特性的精确计算。

根据美国1976年发布的标准大气模型，大气的温度随着高度的增加而逐渐下降，这是因为大气层中的气体受到地球引力的作用，导致气体分子向地表聚集，从而使得地表温度较高，而高空温度较低。

在该模型中，大气的温度变化符合一定的数学规律，科学家们可以根据这一规律对大气的温度分布进行精确计算。

此外，美国1976年发布的标准大气模型还对大气的压强和密度进行了详细描述。

根据该模型，大气的压强和密度随着高度的增加呈指数衰减规律，这意味着大气层越往上，气压和气体密度就越小。

这一规律在航空航天领域具有重要意义，航天器在进入大气层时需要考虑大气的压强和密度变化对其运动轨迹的影响，而美国1976年发布的标准大气模型为航天器的设计和运行提供了重要参考依据。

总的来说，美国1976年发布的标准大气模型是一种重要的大气科学研究工具，它为科学家们研究大气的结构和变化规律提供了重要参考，也为航空航天等领域的工程设计提供了重要依据。

通过对该模型的深入了解，我们可以更好地认识和理解地球大气层的复杂特性，为人类的科学研究和工程实践提供重要支持。

因此，我们应该充分利用美国1976年发布的标准大气模型，不断深化对大气科学的认识，推动大气科学领域的发展和进步。

COESA标准大气模型输出密度曲线
在气动力的计算中，需要获知飞行器所在位置的空气密度来计算动压等参数，因此需要大气模型来计算（不同高度的）空气参数。

jsbsim中采用了U.S.StandardAtmosphere,1976”，NASATM-X-74335（美国标准大气）模型。

标准大气模型描述了不同高度上大气参数的变化，这里我们需要了解两种高度的定义：geometricaltitude（标准高度）和面间的距离；后者考虑了不同高度上重力加速度g的变化，通过g与高度差的积分计算出了重力不变情况下的等效高度，从名字上也能看出来，物体的势能可以直接用这个高度与地表重力加速度、质量相乘获得。

温度、压强、密度
在标准模型中，温度基本是随着高度（分段）线性变化的，所以我们可以方便地将这些数据存在表格里，进行插值计算，而其他
两个参数则可以通过求解方程获得。

根据流体静力平衡和理想气体模型，公式：。

临近空间大气温度和密度特性分析韩丁;盛夏;尹珊建;孙永刚【摘要】To effectively analyze the changing characteristics of atmospheric parameters in near space,based on about 10-year satellite data fromT1MED and ENVISAT,the spatial distribution features of atmospheric temperature and density are statistically calculated,and by compared with USA Standard Atmosphere USSA-1976,the seasonal variation regulations of atmospheric parameter deviation along the altitude,latitude and longitude are analyzed,which can supply some references for the analysis of environmental characteristics and the application of satellite data in near space.The results are as follows:temperature has uniform distribution at mid-latitude and low-latitude areas along the longitude,and the characteristics are different at each altitude along the latitude.Density has uniform distribution at low-latitude areas along the longitude and it decreases monotonically along the latitude.Temperature from USSA 1976 model is larger than that from satellite data and the confidence gradually decreases as altitude increases,while density from USSA 1976 model is smaller than that from satellite data and the error gradually increases as altitude decreases.%为有效分析临近空间大气环境参数的变化特性,利用10年左右的TIMED和ENVISAT卫星探测数据,统计得到了不同高度处大气温度和密度的空间分布特征,并通过与美国标准大气模式USSA-1976对比,分析了大气参数误差随高度、纬度和经度的季节变化,可为临近空间环境特性分析和卫星数据应用提供参考.研究表明,大气温度沿经向在中低纬地区均匀分布,沿纬向在不同高度处的变化特征各异,而大气密度沿经向在低纬地区均匀分布,沿纬向单调减小.USSA-1976模式温度数据整体偏大,随高度上升可信度逐渐降低,而密度数据整体偏小,随高度降低误差逐渐增大.【期刊名称】《遥感信息》【年(卷),期】2017(032)003【总页数】8页(P17-24)【关键词】临近空间;TIMED;ENVISAT;USSA-1976;温度;密度【作者】韩丁;盛夏;尹珊建;孙永刚【作者单位】中国人民解放军96658部队,北京100094;中国人民解放军96658部队,北京100094;中国人民解放军96658部队,北京100094;中国人民解放军96658部队,北京100094【正文语种】中文【中图分类】P351临近空间是指距离地球表面20～100 km高度的区域，也称为“近空间”“亚轨道空间”或“空天过渡区”，包括大气平流层、中间层和部分电离层[1]。

国际标准大气温度
国际标准大气温度是一个基准温度，其定义是指海平面高度，静态状态下，标准大气的温度分布在不同高度上的分布图谱所对应的温度值。

然而，这些定义在不同的时期和国家都有些许变化。

最初提出国际标准大气温度是在1927年由国际大地测量与地球物理联合会提出。

根据当时提出的标准，标准大气温度在海平面高度合一时为15℃，而随着高度的增加，温度将会逐渐下降。

然而随着时间的推移，标准大气温度的定义也从早期的简单定义，逐渐扩展到综合考虑大气压力、密度、温度、湿度和重力等因素的复杂模型。

这也使得标准大气温度的数值不断修正和升级，以适应不同领域的需求。

例如，美国国家航空航天局在1976年提出的标准大气温度为15℃，但是这个数据是在1971到1980年各年份的平均值。

而国际民航组织则在1973年提出的标准大气温度为15℃，但是该定义是要求在一定高度以下。

还有一些国际标准大气温度的定义则是依据特定领域的需求而制定的，例如气象学、天文学、地球物理学等等。

实际上，不同领域的标准大气温度的定义和数值上存在着一定的差异，从而造成了一定的混淆。

总的来说，国际标准大气温度的定义是在渐进发展之中的。

虽然它的定义和数值在不同的领域和不同的国家存在差异，但是它的重要性和实用性在各个领域中都得到了广泛的认可和应用。

U.S_Standard_Atmosphere（1976）美国标准大气（1976）美国标准大气（1976）美国标准大气是一个对中纬度大气年温度、压力、密度垂直分布的假设。

常用于压力测高校准、飞机性能计算、飞机和火箭设计、弹道、气象图和各种大气建模的依据。

其假设大气是干燥，且服从气体定律和流体静力学方程的。

综上所述，其包含了温度、压力和密度的垂直分布。

其考虑到了地球自转和昼夜循环，半年一次的变化、活跃到安静的地磁场和太阳黑子条件。

美国标准大气（1976）是一个理想条件下，北纬45度地面至1000KM高空地球大气年均状态。

其定义气象要素是海平面温度、压力、和1000KM温度廓线。

1976年标准大气使用的是数十年来沿用的海平面值。

温度——288.15K(15℃)压力——101325Pa（1013.25mbar，760mm of Hg,or 29.92 in.of(HG)密度——1225g/m3(1.225g/l)平均摩尔质量——28.964g/mol参数包括这些缩写，标准大气：Z——高度T——温度（K）P——气压（Pa）ρ——密度（1kg/m3）n——每立方米分子数密度ν——平均每秒碰撞率l——平均自由程（m）η——绝对粘度（1Pa s=1000c P）v s——音速（m/s）g——重力加速度海平面大气组成：N——78.084% He——0.000524O2——20.9476 Kr——0.000114Ar——0.934 Xe——0.0000087CO2——0.0314 CH4——0.0002Ne——0.001818 H2——0.00005温度和压力在对流层和平流层下部计算公式为：T/K P/PaH≤11000m 288.15-0.0065H 101325(288.15/T)-5.2557711000m<="" p="">20000m<="">这里H=rZ/(r+Z)为地势高度，r是北纬45°平均地球半径，取6356766m.对于32Km高度，ρ=0.003483677（P/T）Z /m T /K P /Pa ρ /kg m–3n /m –3ν /s –1l /m η /Pa s W m –1 K –1 v s /ms–1g /m s –25000 320 .68 1 .778E+05 1 .931 4 .015E+25 1 .151E+10 4 .208E – 08 1 .942E – 05 0 .02788 359 .0 9 .822 4500 317 .42 1 .685E+05 1 .849 3 .845E+25 1 .096E+10 4 .395E – 08 1 .927E –05 0 .02763 357 .2 9 .830 4000 314 .17 1 .596E+05 1 .770 3 .680E+25 1 .044E+10 4 .592E – 08 1 .912E – 05 0 .02738 355 .3 9 .819 3500 310 .91 1 .511E+05 1 .693 3 .520E+25 9 .933E+09 4 .800E – 08 1 .897E – 05 0 .02713 353 .5 9 .818 3000 307 .66 1 .430E+05 1 .619 3 .366E+25 9 .448E+09 5 .019E – 08 1 .882E –05 0 .02688 351 .6 9 .816 2500 304 .41 1 .352E+05 1 .547 3 .217E+25 8 .982E+09 5 .252E – 08 1 .867E – 05 0 .02663 349 .8 9 .814 2000 301 .15 1 .278E+05 1 .478 3 .102E+25 8 .623E+09 5 .447E – 08 1 .852E – 05 0 .02638 347 .9 9 .813 1500 297 .90 1 .207E+05 1 .411 2 .935E+25 8 .106E+09 5 .757E – 08 1 .836E –05 0 .02613 346 .0 9 .811 1000 294 .65 1 .139E+05 1 .347 2 .801E+25 7 .693E+09 6 .032E – 08 1 .821E – 05 0 .02587 344 .19 .810 – 500 291 .40 1 .075E+05 1 .285 2 .672E+25 7 .298E+09 6 .324E – 08 1 .805E – 05 0 .02562 342 .2 9 .8080 288 .15 1 .013E+05 1 .225 2 .547E+25 6 .919E+09 6 .633E –08 1 .789E – 05 0 .02533 340 .3 9 .807 500 284 .90 9 .546E+04 1 .167 2 .427E+25 6 .556E+09 6 .961E – 08 1 .774E – 05 0 .02511 338 .4 9 .805 1000 281 .65 8 .988E+04 1 .112 2 .311E+25 6 .208E+09 7 .310E – 08 1 .758E – 05 0 .02485 336 .4 9 .804 1500 278 .40 8 .456E+04 1 .058 2 .200E+25 5 .874E+09 7 .680E – 081 .742E – 05 0 .02459 334 .5 9 .802 2000 275 .15 7 .950E+04 1 .0072 .093E+25 5 .555E+09 8 .073E – 08 1 .726E – 05 0 .02433 332 .5 9 .801 2500 271 .91 7 .469E+04 0 .957 1 .990E+25 5 .250E+09 8 .491E – 08 1 .710E – 05 0 .02407 330 .6 9 .799 3000 268 .667 .012E+04 0 .909 1 .891E+25 4 .959E+098 .937E – 08 1 .694E –05 0 .02381 328 .69 .797 3500 265 .41 6 .579E+04 0 .863 1 .795E+25 4 .680E+09 9 .411E – 08 1 .678E – 05 0 .02355 326 .6 9 .796 4000 262 .17 6 .166E+04 0 .819 1 .704E+25 4 .414E+09 9 .917E – 08 1 .661E – 05 0 .02329 324 .6 9 .794 4500 258 .92 5 .775E+04 0 .777 1 .616E+25 4 .160E+09 1 .046E – 07 1 .645E –05 0 .02303 322 .6 9 .793 5000 255 .68 5 .405E+04 0 .736 1 .531E+25 3 .918E+09 1 .103E – 07 1 .628E – 05 0 .02277 320 .6 9 .791 5500 252 .43 5 .054E+04 0 .697 1 .450E+25 3 .687E+09 1 .165E – 07 1 .612E – 05 0 .02250 318 .5 9 .790 6000 249 .194 .722E+04 0 .660 1 .373E+25 3 .467E+09 1 .231E – 07 1 .595E –05 0 .02224 316 .5 9 .788 6500 245 .94 4 .408E+04 0 .664 1 .299E+25 3 .258E+09 1 .302E – 07 1 .578E – 05 0 .02197 314 .4 9 .787 7000 242 .70 4 .111E+04 0 .590 1 .227E+25 3 .058E+09 1 .377E – 07 1 .561E – 05 0 .02170 312 .3 9 .785 7500 239 .46 3 .830E+04 0 .557 1 .159E+25 2 .869E+09 1 .458E – 07 1 .544E –05 0 .02144 310 .2 9 .784 8000 236 .22 3 .565E+04 0 .526 1 .093E+25 2 .689E+09 1 .545E – 07 1 .527E – 05 0 .02117 308 .19 .782 8500 232 .97 3 .315E+04 0 .496 1 .031E+25 2 .518E+09 1 .639E – 07 1 .510E – 05 0 .02090 306 .0 9 .781 9000 229 .73 3 .080E+04 0 .467 9 .711E+24 2 .356E+09 1 .740E – 07 1 .493E –05 0 .02063 303 .9 9 .779 9500 226 .49 2 .858E+04 0 .440 9 .141E+24 2 .202E+09 1 .848E – 07 1 .475E – 05 0 .02036 301 .7 9 .777 0000 223 .25 2 .650E+04 0 .414 8 .598E+24 2 .056E+091 .965E – 07 1 .458E – 05 0 .02009 299 .5 9 .776 10500 220 .012 .454E+04 0 .389 8 .079E+24 1 .918E+09 2 .091E – 07 1 .440E –05 0 .01982 297 .4 9 .774 11000 216 .77 2 .270E+04 0 .365 7 .585E+24 1 .787E+09 2 .227E – 07 1 .422E – 05 0 .01954 295 .2 9 .773 11500 216 .65 2 .098E+04 0 .337 7 .016E+24 1 .653E+09 2 .408E – 07 1 .422E – 05 0 .01953 295 .1 9 .771 12000 216 .65 1 .940E+04 0 .312 6 .486E+24 1 .528E+09 2 .605E – 07 1 .422E –05 0 .01953 295 .1 9 .770 12500 216 .65 1 .793E+04 0 .288 5 .996E+24 1 .412E+09 2 .818E – 07 1 .422E – 05 0 .01953 295 .1 9 .768 13000 216 .65 1 .658E+04 0 .267 5 .543E+24 1 .306E+09 3 .048E – 07 1 .422E – 05 0 .01953 295 .1 9 .767 13500 216 .65 1 .533E+04 0 .246 5 .124E+24 1 .207E+09 3 .297E – 07 1 .422E –05 0 .01953 295 .1 9 .765 14000 216 .65 1 .417E+04 0 .228 4 .738E+24 1 .116E+09 3 .566E – 07 1 .422E – 05 0 .01953 295 .1 9 .764 14500 216 .65 1 .310E+04 0 .211 4 .380E+24 1 .032E+09 3 .857E – 07 1 .422E – 05 0 .01953 295 .1 9 .762 15000 216 .65 1 .211E+04 0 .195 4 .049E+24 9 .538E+08 4 .172E – 07 1 .422E –05 0 .01953 295 .1 9 .761 16000 216 .65 1 .035E+04 0 .166 3 .461E+24 8 .153E+08 4 .881E – 07 1 .422E – 05 0 .01953 295 .1 9 .75817000 216 .65 8 .850E+03 0 .142 2 .959E+24 6 .969E+08 5 .710E – 07 1 .422E – 05 0 .01953 295 .1 9 .754 18000 216 .65 7 .565E+03 0 .122 2 .529E+24 5 .958E+08 6 .680E – 07 1 .422E –05 0 .01953 295 .1 9 .751 19000 216 .65 6 .467E+03 0 .1042 .162E+24 5 .093E+08 7 .814E – 07 1 .422E – 05 0 .01953 295 .1 9 .748 20000 216 .65 5 .529E+03 8 .891E –02 1 .849E+24 4 .354E+08 9 .139E – 07 1 .422E – 05 0 .01953 295 .1 9 .745 21000 217 .58 4 .729E+03 7 .572E – 02 1 .574E+24 3 .716E+08 1 .073E –06 1 .427E – 05 0 .01961 295 .1 9 .742 22000 218 .57 4 .048E+03 6 .451E – 02 1 .341E+24 3 .173E+08 1 .260E – 06 1 .432E – 050 .01970 296 .4 9 .739 23000 219 .57 3 .467E+03 5 .501E – 021 .144E+242 .712E+08 1 .477E – 06 1 .438E – 05 0 .01978 297 .1 9 .736 24000 220 .56 2 .972E+034 .694E –02 9 .759E+23 2 .319E+08 1 .731E – 06 1 .443E – 05 0 .01986 297 .7 9 .733 25000 221 .55 2 .549E+03 4 .008E – 028 .334E+23 1 .985E+08 2 .027E –06 1 .448E – 05 0 .01995 298 .49 .730 26000 222 .54 2 .188E+03 3 .426E – 02 7 .123E+23 1 .700E+08 2 .372E – 06 1 .454E – 05 0 .02003 299 .1 9 .727 27000 223 .54 1 .880E+03 2 .930E – 02 6 .092E+23 1 .458E+08 2 .773E – 06 1 .459E – 05 0 .02011 299 .7 9 .724 28000 224 .53 1 .610E+03 2 .508E –02 5 .214E+23 1 .250E+08 3 .240E – 06 1 .465E – 05 0 .02020 300 .4 9 .721 29000 225 .52 1 .390E+03 2 .148E – 02 4 .466E+23 1 .073E+08 3 .783E –06 1 .470E – 05 0 .02028 301 .1 9 .718 30000 226 .51 1 .197E+03 1 .841E – 02 3 .828E+23 9 .219E+07 4 .414E – 06 1 .475E – 05 0 .02036 301 .7 9 .715 31000 227 .50 1 .031E+03 1 .579E – 02 3 .283E+23 7 .925E+07 5 .146E – 06 1 .481E – 05 0 .02044 302 .4 9 .712 32000 228 .49 8 .891E+02 1 .356E –02 2 .813E+23 6 .818E+07 5 .995E – 06 1 .486E – 05 0 .02053 303 .0 9 .709 33000 230 .97 7 .673E+02 1 .157E – 02 2 .406E+23 5 .852E+07 7 .021E –06 1 .499E – 05 0 .02073 304 .7 9 .706 34000 233 .74 6 .634E+02 9 .887E – 03 2 .056E+23 5 .030E+07 8 .218E – 06 1 .514E – 050 .02096 306 .5 9 .703 35000 236 .51 5 .746E+02 8 .463E – 031 .760E+23 4 .331E+07 9 .601E – 06 1 .529E – 05 0 .02119 308 .3 9 .70036000 239 .28 4 .985E+02 7 .258E –03 1 .509E+23 3 .736E+07 1 .120E – 05 1 .543E – 05 0 .02142 310 .1 9 .697 38000 244 .82 3 .771E+02 5 .367E – 03 1 .116E+23 2 .794E+07 1 .514E –05 1 .572E – 05 0 .02188 313 .7 9 .690 40000 250 .35 2 .871E+02 3 .996E – 03 8 .308E+22 2 .104E+07 2 .034E – 05 1 .601E – 05 0 .02233 317 .2 9 .684 42000 255 .88 2 .200E+02 2 .995E – 03 6 .227E+22 1 .594E+07 2 .713E – 05 1 .629E – 05 0 .02278 320 .7 9 .678 44000 261 .40 1 .695E+02 2 .259E –03 4 .697E+22 1 .215E+07 3 .597E – 05 1 .657E – 05 0 .02323 324 .1 9 .672 46000 266 .93 1 .313E+02 1 .714E – 03 3 .564E+22 9 .318E+06 4 .740E –05 1 .685E – 05 0 .02376 327 .5 9 .666 48000 270 .65 1 .023E+02 1 .317E – 03 2 .738E+22 7 .208E+06 6 .171E – 05 1 .704E – 05 0 .02397 329 .8 9 .660 50000 270 .65 7 .978E+01 1 .027E – 03 2 .135E+22 5 .620E+06 7 .913E – 05 1 .703E – 05 0 .02397 329 .8 9 .654 52000 269 .03 6 .221E+01 8 .056E –04 1 .675E+22 4 .397E+06 1 .009E – 04 1 .696E – 05 0 .02384 328 .8 9 .648 54000 263 .52 4 .834E+01 6 .390E – 04 1 .329E+22 3 .452E+06 1 .272E –04 1 .660E – 05 0 .02340 325 .4 9 .642 56000 258 .02 3 .736E+015 .045E – 04 1 .049E+22 2 .696E+06 1 .611E – 04 1 .640E – 05 0 .02296 322 .0 9 .636 58000 252 .52 2 .872E+01 3 .963E – 048 .239E+21 2 .095E+06 2 .051E – 04 1 .612E – 05 0 .02251 318 .69 .632 60000 247 .02 2 .196E+01 3 .097E –04 6 .439E+21 1 .620E+06 2 .624E – 04 1 .584E – 05 0 .02206 315 .1 9 .624 65000 233 .29 1 .093E+01 1 .632E – 04 3 .393E+21 8 .294E+05 4 .979E –04 1 .512E – 05 0 .02093 306 .2 9 .609 70000 219 .59 5 .221 8 .283E – 05 1 .722E+21 4 .084E+05 9 .810E – 04 1 .438E – 05 0 .01978 297 .1 9 .594 75000 208 .40 2 .388 3 .992E –05 8 .300E+20 1 .918E+05 2 .035E – 03 1 .376E – 05 0 .01883 289 .4 9 .579 80000 198 .64 1 .052 1 .846E – 05 3 .838E+20 8 .656E+04 4 .402E – 03 1 .321E – 05 0 .01800 282 .5 9 .564 85000 188 .89 4 .457E – 018 .220E – 06 1 .709E+20 3 .766E+04 9 .886E – 03 1 .265E – 05 0 .01716 275 .5 9 .550 90000 186 .87 1 .836E – 01 3 .416E – 06 7 .116E+19 1 .560E+04 2 .370E – 02 9 .53595000 188 .42 7 .597E –02 1 .393E –06 2 .920E+19 6 .440E+03 5 .790E – 02 9 .520100000 195 .08 3 .201E –02 5 .604E –07 1 .189E+19 2 .680E+03 1 .420E – 01 9 .505110000 240 .00 7 .104E –03 9 .708E –08 2 .144E+18 5 .480E+02 7 .880E – 01 9 .476120000 360 .00 2 .538E –03 2 .222E –08 5 .107E+17 1 .630E+02 3 .310 9 .447130000 469 .27 1 .251E –03 8 .152E –09 1 .930E+17 7 .100E+01 8 .800 9 .418140000 559 .63 7 .203E –04 3 .831E –09 9 .322E+16 3 .800E+01 1 .800E+01 9 .389150000 634 .39 4 .542E –04 2 .076E –09 5 .186E+16 2 .300E+01 3 .300E+01 9 .360 160000 696 .29 3 .040E – 04 1 .233E – 09 3 .162E+16 1 .500E+01 5 .300E+01 9 .331 170000 747 .57 2 .121E –04 7 .815E –10 2 .055E+16 1 .000E+01 8 .200E+01 9 .302 180000 790 .07 1 .527E – 04 5 .194E – 10 1 .400E+16 7 .200 1 .200E+02 9 .274 190000 825 .16 1 .127E –04 3 .581E –10 9 .887E+15 5 .200 1 .700E+02 9 .246 200000 854 .56 8 .474E – 05 2 .541E – 10 7 .182E+15 3 .900 2 .400E+02 9 .218 220000 899 .01 5 .015E – 05 1 .367E – 10 4 .040E+15 2 .300 4 .200E+02 9 .162 240000 929 .73 3 .106E –05 7 .858E –11 2 .420E+15 1 .400 7 .000E+02 9 .106 260000 950 .99 1 .989E –05 4 .742E –11 1 .515E+15 9 .300E – 01 1 .100E+03 9 .051 280000 965 .75 1 .308E –05 2 .971E –11 9 .807E+14 6 .100E –01 1 .700E+03 8 .997 300000 976 .01 8 .770E – 06 1 .916E – 11 6 .509E+14 4 .200E – 01 2 .600E+03 8 .943 320000 983 .16 5 .980E –06 1 .264E –114 .405E+14 2 .900E – 01 3 .800E+03 8 .889 340000 988 .15 4 .132E –06 8 .503E –12 3 .029E+14 2 .000E –01 5 .600E+03 8 .836 360000 991 .65 2 .888E – 06 5 .805E – 12 2 .109E+14 1 .400E – 01 8 .000E+03 8 .784 380000 994 .10 2 .038E –06 4 .013E –12 1 .485E+14 1 .000E – 01 1 .100E+04 8 .732 400000 995 .83 1 .452E –06 2 .803E –12 1 .056E+147 .200E –02 1 .600E+048 .680 450000 998 .22 6 .447E – 07 1 .184E – 12 4 .678E+13 3 .300E – 02 3 .600E+04 8 .553 500000 999 .24 3 .024E –07 5 .215E –13 2 .192E+13 1 .600E – 02 7 .700E+04 8 .429 550000 999 .67 1 .514E –07 2 .384E –13 1 .097E+13 8 .400E –03 1 .500E+05 8 .307 600000 999 .85 8 .213E – 08 1 .137E – 13 5 .950E+12 4 .800E – 032 .800E+05 8 .188 650000 999 .934 .887E –085 .712E –143 .540E+12 3 .100E – 034 .800E+05 8 .072 700000 999 .97 3 .191E –08 3 .070E –14 2 .311E+12 2 .200E –03 7 .300E+05 7 .958 750000 999 .98 2 .260E – 08 1 .788E – 14 1 .637E+12 1 .700E – 03 1 .000E+067 .846 800000 999 .99 1 .704E –08 1 .136E –14 1 .234E+12 1 .400E –03 1 .400E+06 7 .737 850000 1000 .00 1 .342E – 08 7 .824E – 159 .717E+11 1 .200E – 03 1 .700E+06 7 .630 900000 1000 .00 1 .087E –08 5 .759E –15 7 .876E+11 1 .000E –03 2 .100E+06 7 .525 950000 1000 .00 8 .982E –09 4 .453E – 15 6 .505E+11 8 .700E – 04 2 .600E+06 7 .422 1000000 1000 .00 7 .514E –09 3 .561E –15 5 .442E+11 7 .500E –04 3 .100E+06 7 .322。

The AtmosphereFor the purposes of analyzing aircraft performance, the characteristics of the atmosphere can be simplified into a standard model. This section discusses the characteristics of the atmosphere up to the top of the stratosphere (approximately 65,600 ft). The aircraft performance engineer must know the values of atmospheric temperature, T , pressure, p , density, ρ, and the local speed of sound, a , throughout the aircraft’s flight.Equations are given here without derivation. For derivation the student should refer to Lan & Roskam (Ref 2).International Standard Atmosphere (ISA)The most commonly used atmosphere model is the International Civil AviationOrganization (ICAO) Standard Atmosphere, of which the main part is the International Standard Atmosphere (ISA). At all altitudes of interest to an aircraft performanceengineer, the ISA model is the same as that of the 1976 U.S. Standard Atmosphere, and the MIL-STD Standard Atmosphere.ISA assumes the following characteristics: Pressure altitude, h [ft] 36,089 ftT 0T 0' TemperatureThe altitude used in most performance calculations is not the geometric altitude but the pressure altitude. The performance engineer is usually interested in the air pressure, density and temperature in the immediate vicinity of the airplane. Absolute altitude (except for calculations for time to climb) is of secondary importance.Source: FAA AC 61-23BFigure 1. AltimeterAn aircraft altimeter does not directly measure altitude. It is an aneroid barometer (Figure 1), and the dial converts the pressure value into an equivalent altitude. If the sea level pressure is not the standard value (as a result of high or low pressure weather systems), the altimeter must be corrected manually (using a knurled knob) to take account of the difference at that locality and at that time. The foregoing procedure applies below 18,000 ft MSL. Above that altitude, the altimeter is set to standard day pressure (29.92 inches of mercury) and pilots fly to the pressure altitude for a standard day.TroposphereAt any altitude h [ft] within the troposphere, the temperature is given by:T=T+λh (1) The pressure is:p=p01+λhT0 f f f f f f f f ff g5.2561 (2) The density is derived from the standard gas equation:ρ=pgRTf f f f f f f f f f f f f f (3)Sometimes you may see reference to “density altitude”, which is the altitude on a standard day which has the same air density as that actually experienced. Thus a highervalue of density altitude implies that the air is less dense than that of a standard atmosphere at the same pressure altitude. Both aircraft and engine performance are degraded as the air density decreases.The local speed of sound is a function only of temperature:q w w w w w w w w w w w w w w w w w w w w w w w (4) a=γgRTStratosphereIn the stratosphere the temperature is independent of altitude and has a value of 390 0R or -69.7 0F.Pressure is given byf f f f f f=0.2234e@h@36,08920806.7f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f (5) ppDensity can be derived from the standard gas equation shown above.Non-Standard AtmosphereThere are many non-standard atmospheres, of which the most simple involves a temperature offset from the standard day temperature gradient, as shown in the figure above. On a hot day the whole atmosphere is displaced upwards, so that the geometric height of the tropopause is increased. For example, at ISA + 15 0C (+ 27 0F) the geometric height of the tropopause increases by about 2,200 ft. At a given geometric altitude (except at sea level) air pressure increases, because there is now more atmosphere bearing down on a given area. There is no correction for ambient temperature on a standard altimeter so pilots must be aware that on a cold day the geometric altitude of an airplane will be lower than the pressure altitude as indicated on the altimeter. For example, on an ISA - 10 0C (- 18 0F) day, an altimeter indicating 6000 ft will actually be at 5787 ft MSL.Fortunately the vertical displacement of the atmosphere doesn’t concern us (and thus makes calculations a lot easier), because we are concerned only with pressure altitude, and on a pressure altitude scale (as shown on the figure above), the height of the tropopause remains at a pressure altitude of 36,089 ft.TroposphereThe temperature offset is defined by:T.=T+∆T (6)so that the temperature at altitude h is:T .=T 0.+λh (7)The assumed pressure variation with altitude is unchanged (remember that the altitude is defined as the pressure altitude, not geometric altitude).The density is therefore: ρ.=p gRT .f f f f f f f f f f f f f f f f f f f(8)where the pressure, p , is obtained from Eq. (2) above.StratosphereTemperature in the stratosphere is given by:T .=390+∆T 0R (9)Pressure, by definition, remains independent of temperature offset from an ISA day and is therefore defined by Eq. (5). Density as before can be calculated from Eq. (8).There are many other non-standard atmospheres, some of which are defined by MIL-STDs. A review of some of these atmosphere models may be found in Ref 1.Effect of humidityISA assumes dry air. Water vapor has a lower molecular weight than either nitrogen or oxygen, so humid air is less dense than dry air at the same temperature and pressure.According to Roskam (Ref 2), the density of saturated air is 1.8% less than that of dry air. This is small but significant. However, for the purposes of performance calculations this effect is usually neglected.Absolute ViscosityFor skin friction calculations, Reynolds Number must be calculated, which implies that absolute viscosity must be known. This is a function only of temperature and may be determined from the equation from Ref. 2: µ=0.3170T 0Rbc 32f f f f f 734.7T 0R +216f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f gH L J I MK X 10@10lb second ft2f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f(10)References:1.Zuppardo, Joseph S., “ Graphical Comparison of U.S. Standard Atmospheres andMilitary Standard Climatic Extremes”, Wright Patterson AFB Air Force Materiel Command Dept ASC/ENFTA, Report ASC-TR-93-5002, Feb 1993.2Lan, Chuan-Tau, and Roskam, Jan, “Airplane Aerodynamics and Performance”, Roskam Aviation and Engineering, 1981.。

标准大气压的三种表述方法的相关标准和规范前言标准大气压是描述地球上大气压强的参考值，是衡量大气压强的基准。

在科学、工程和气象学等领域中，常常需要使用标准大气压来进行计算、评估和设计。

本文将详细介绍标准大气压的三种表述方法，包括国际标准大气（ISA）、美国标准大气（US Standard Atmosphere）以及国际民航组织标准大气（ICAO Standard Atmosphere）。

我们将从标准的制定、执行和效果等方面进行阐述，并对三种表述方法进行比较和分析。

1. 国际标准大气（ISA）1.1 标准的制定国际标准大气（International Standard Atmosphere，简称ISA）是由国际民航组织（International Civil Aviation Organization，简称ICAO）于1953年制定的，后来由联合国教科文组织（United Nations Educational, Scientific and Cultural Organization，简称UNESCO）于1976年再次修订和发布。

1.2 标准的执行国际标准大气被广泛应用于航空、航天、气象学和大气科学等领域。

在航空领域中，飞行员和飞行控制员使用国际标准大气来计算和验证飞行参数，以确保飞行安全。

在气象学和大气科学中，国际标准大气被用来分析和模拟大气层的结构和性质。

1.3 标准的效果国际标准大气提供了一种统一和标准化的方式来描述大气压强和温度随高度的变化。

它为航空和航天工程提供了一个理想的参考模型，使得飞行员和工程师能够进行准确的计算和预测。

2. 美国标准大气（US Standard Atmosphere）2.1 标准的制定美国标准大气（US Standard Atmosphere）是由美国标准大气局（U.S. Standard Atmosphere）于1958年制定的，后来在1976年进行了修订和更新。

空气质划分标准
空气质量划分标准是指根据空气中污染物的种类和浓度，将空气质量分为不同等级的标准。

这些标准通常由政府或环境保护机构制定，旨在保护公众健康和环境。

以下是一些历史上真实存在的空气质量划分标准：
1. 美国环保署（EPA）空气质量指数（AQI）：该标准将空气质量划分为六个等级，从0到500，其中0到50为“良好”，51到100为“中等”，101到150为“敏感人群不健康”，151到200为“不健康”，201到300为“非常不健康”，301到500为“危险”。

2. 中国空气质量指数（AQI）：该标准将空气质量划分为六个等级，从0到500，其中0到50为“优”，51到100为“良好”，101到150为“轻度污染”，151到200为“中度污染”，201到300为“重度污染”，301到500为“严重污染”。

3. 欧洲空气质量指数（AQI）：该标准将空气质量划分为五个等级，从0到500，其中0到50为“优”，51到100为“良好”，101到200为“中等”，201到300为“差”，301到500为“非常差”。

4. 世界卫生组织（WHO）空气质量指南：该标准将空气质量划分为四个等级，从0到500，其中0到50为“安全”，51到100为“可接受”，101到200为
“不健康”，201到300为“非常不健康”，301到500为“危险”。

这些标准的制定和实施对于保护公众健康和环境至关重要。

通过监测和控制污染物的排放，可以减少空气污染对人体健康和环境的影响。

标准大气条件由权威性机构颁布的一种“模式大气”。

它依据实测资料，用简化方式近似地表示大气温度、压力和密度等参数的平均垂直分布。

标准大气主要是应飞行器设计和飞行器试验的需要而提出的。

国际性组织（如国际民用航空组织、国际标准化组织）颁布的称为国际标准大气，国家机构颁布的称为国家标准大气。

20世纪20年代美国首次制定“标准大气”，接着国际航空联合会在美国标准大气的基础上制定了第一个国际标准大气。

随后，各个国家、各种组织的标准大气也陆续出现。

1976年美国国家海洋和大气局、美国国家航空航天局、美国空军部合作制定了新的美国国家标准大气，它依据大量的有关中间层和较低热层的探空火箭探测资料和人造地球卫星对一个以上完整的太阳活动周期的探测结果，把高度扩展到1000公里，内容也大大增加。

1980年中国国家标准总局发布了中华人民共和国国家标准大气（30公里以下部分）。

比较通用的国际标准大气的主要内容包括：①基本假定：大气是静止的,空气为干燥洁净的理想气体,在规定温度-高度廓线和海平面上的温度、压力和密度初始值后，通过对大气静力方程和气体状态方程的积分，获得压力和密度数据。

②海平面大气物理属性等主要常数：海平面温度t0=15°C；海平面绝对温度T0=288.15K；海平面空气密度ρ0=1.225千克/米3；海平面空气压力p0=101325帕(1013.25毫巴或760毫米汞柱);海平面音速a0=340.294米/秒；标准重力加速度g0=9.80665米/秒2干空气的气体常数R=287.05278焦耳/开·千克。

③大气温度随高度变化的计算公式。

④大气压力随高度变化的计算公式。

⑤空气密度随高度变化的计算公式。

此外，还有粘性系数、分子碰撞频率、分子量等。

根据上述各公式计算出来的数据排列成表即为标准大气表。

各地的实际大气与标准大气之间存在着一定的差别。