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1.
以较为精确的大气辐射传输模式为基础,研制出晴天地表总辐射和净辐射瞬时值的计算方案。与以往的经验计算方法不同,该方案将辐射传输带模式的思路引入地面太阳辐射计算,并尽可能将大气中吸收和散射物质对太阳辐射的影响考虑进去,从而使该方法具有较好的精确性和普适性。在此基础上采用了Kokhanovsky等人提出的大气气溶胶反射率和透过率参数化方案,使得气溶胶对地面总辐射和净辐射的影响得到较好的处理。采用的自变量都是数值预报模式或卫星观测能提供的气象要素,因此该方案即可用于数值预报模式或陆面过程模式计算地表辐射平衡,又可以利用卫星观测或再分析资料估算地面太阳能资源分布。利用美国能源部三个大气辐射观测站点2005年全年的观测资料及欧洲宇航局提供的卫星反演气溶胶资料对计算方案进行了检验。结果表明,该方法十分精确,所有点的平均相对误差都小于6%,误差的均方差都小于0.3 W•m-2。  相似文献   

2.
GRAPES-Meso模式浅对流云辐射效应的改进试验   总被引:1,自引:0,他引:1  
在万子为等(2015)对GRAPES-Meso模式浅对流参数化改进的基础上,进一步引入了浅对流云量诊断计算,并设计旨在完善浅对流云辐射效应的浅云云量和云中水凝物的补偿方案,以改进模式低层云量偏少和浅对流云辐射效应不足的问题。通过对数值试验结果的诊断和对比分析以及与观测的比较,重点考察了浅对流云量计算与浅对流激发的协调性、浅对流云对低云补偿后所产生的辐射效应以及对模式地面要素预报的影响等,验证了改进方案的合理性与有效性。结果表明:(1)浅对流云量诊断计算合理,其云覆盖区与浅对流激发区相吻合,引入浅对流云量的计算可减小模式云量的计算偏差、使其向观测结果靠近;(2)改进方案在浅对流发生区低层0.5-4 km高度范围内,对影响模式云辐射过程的浅云云量和云中水凝物形成有效补偿,最明显的浅云补偿在1-1.5 km高度处,浅对流活跃时期浅对流过程对浅云水凝物(云水和雨水之和)的补偿量可达20%-55%;(3)云光学厚度对浅云水凝物的补偿响应合理,即水凝物的补偿引起云光学厚度增大,两者的变化特征在时空分布上十分相似,且云光学厚度之变化受云水补偿的影响比受雨水补偿的影响更明显;(4)在白天时段,浅云补偿所产生的辐射效应使模式地表太阳总辐射有所下降,缩小了与观测的偏差,进而使地表温度和地面2 m气温模拟偏差减小。改进方案在缓解模式云量偏少、地表太阳总辐射偏强和地面2 m气温偏高等方面的作用,在批量试验中得到了验证。   相似文献   

3.
北京地区太阳紫外辐射的观测与分析研究   总被引:10,自引:2,他引:10  
白建辉  王庚辰 《大气科学》1994,18(3):341-347
利用北京地区太阳辐射和其它常规气象观测资料,得到了到达地面的太阳紫外辐射的计算公式,并将计算值与观测值进行了比较,两者吻合得比较好。最后给出了北京地区地面太阳紫外总辐射的变化趋势,计算结果表明,地面太阳紫外总辐射对大气浑浊度的变化比对大气臭氧总量的变化敏感得多。  相似文献   

4.
《气象》2019,(8)
<正>云可以将大气动力、辐射、水分循环和下垫面等多个物理过程相互耦合、通过多种方式影响气候系统,是当前气候模拟和气候变化研究中最大的不确定因子之一。该书首先结合地面与多种卫星观测资料,分别给出全球和东亚地区云与太阳辐射的变化特征及归因,研究了地面太阳辐射的变化对地面气温的影响程度。其次,基于卫星观测资料研究了气候模式中描述云辐射过程的关键物理参数(抗相关厚度)的  相似文献   

5.
我们利用在中国西部黑河流域所进行的陆气相互作用实验的预试验期间地面和卫星观测资料,研究了在于旱地区地表辐射收支演算中所遇到的困难。通过理论辐射传输计算和用卫星资料对云的反演可以得到地表辐射。计算结果与地表测量的太阳辐射和红外辐射比较表明在有些情况下会发生较大的误差。误差主要是由于缺乏气溶胶资料.云反演时的不确定性以及地面观测与卫星测量之间的时间差异所引起。在无云情况下,模式计算的太阳辐射通量系统大于测量值,当地面温度大于50℃和由于不稳定边界层造成尘埃古量大时计算误差特别大,误差的原因是计算中没有考虑气溶胶.我们发现在下午当气溶胶单次散射反射率取为9.5.光学厚度近似地取为0.2时计算误差可以减小,计算的地面太阳辐射通量和实测值比较一致,然而在大气中太阳辐射如此强的吸收原因仍不清楚.对地面测量和卫星测量资料都可以用的个例研究结果表明,地表净太阳辐射通量和红外向下辐射通量的平均误差分别为4.3和-4.7W/m^2.相应的均方根误差分别为17.4和22.1W/m^2.较大的误差出现在云量较少时,这可能是反演中误把气溶胶当成了云所造成的.研究结果强调了气溶胶在地表辐射计算中的重要性。同时,由于该地区地表温度的日变化非常大,而地面红外辐射的计算,要求温度测量有较高的时间分辨率,因此在干旱地区地面辐射计算中,从卫星资料反演气溶胶和地面温度应予以最优先考虑.  相似文献   

6.
利用专门为太阳能资源评估应用的 WRF-Solar数值模式系统,结合 MODIS 气溶胶光学厚度(AOD550 nm)数据,设置了5种山东区域总辐射模拟方案,使用山东济南、福山、吉县3个太阳辐射站总辐射观测数据,对晴天、阴天、雨天以及四季代表月等逐时总辐射模拟结果进行了对比检验。 结果表明:WRF-Solar数值模式对总辐射模拟能力在晴天和少云天最好,阴雨天较差,四季代表月中,天气过程较少的秋季和冬季模拟效果较好,春季次之,夏季相对较差;晴天和少云天、阴天和雨天以及不考虑天气过程的四季代表月所有日条件下,长、短波辐射方案分别采用RRTMG方案、new Goddard 方案,积云对流参数化方案均采用Grell 3D集合方案,同时使用AOD550 nm的气溶胶数据的总辐射模拟能力最强;WRF-Solar模式中加入 MODIS 气溶胶光学厚度资料后,山东区域晴天总辐射模拟结果明显改善,秋季、冬季代表月亦明显改善,但阴天和雨天总辐射模拟结果改善不明显,低能见度日总辐射模拟结果有所改善。  相似文献   

7.
太湖地区太阳紫外辐射的初步研究   总被引:6,自引:1,他引:6       下载免费PDF全文
本文利用 1998年 1— 12月太湖湖泊生态系统研究站的太阳辐射观测资料进行分析 ,得到此间太湖地区近地面太阳紫外辐射及其占太阳总辐射比例的变化特征。结果表明 :该地区太阳紫外辐射年平均日总量为 0 .73MJ· m-2· d-1,大于临近的上海 ;紫外辐射瞬时极大值为 5 0 W· m-2 ;紫外辐射在总辐射中所占比例年平均值为 6 .2 % ,也比上海要大 ;其年变化特征与上海相同 ,夏季大冬季小  相似文献   

8.
WRF模式模拟的地表短波辐射与实况对比分析   总被引:2,自引:0,他引:2  
王明欢  赖安伟  陈正洪  白永清  成驰  李芬 《气象》2012,38(5):585-592
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。  相似文献   

9.
根据本站逐日总辐射观测资料,计算出紫外线辐射量,然后反查出该量与地面天气要素间的关系,从而根据每天的气象要素预报作出紫外线辐射强度预报.  相似文献   

10.
毕道华  陈月娟 《大气科学》1993,17(5):513-522
本文介绍一个简单、经济的适用于各种多层大气环流模式中计算臭氧加热率的参数化方案,利用这一方案,可根据臭氧总量气候观测值及其垂直分布资料计算臭氧加热率,也可以在模式中加入臭氧方程,用预报的臭氧含量计算臭氧加热率.用此方案对单站气候资料试算,结果指出,随着高度的增加,臭氧吸收太阳辐射对大气太阳加热率的贡献逐渐接近、达到并在平流层50hPa附近明显超过其它物质如水汽的贡献.此方案用于九层大气环流模式时,对其辐射加热率的计算有较理想的改进,并使模拟的大气温度垂直分布更符合观测事实.  相似文献   

11.
The global energy balance from a surface perspective   总被引:1,自引:1,他引:0  
In the framework of the global energy balance, the radiative energy exchanges between Sun, Earth and space are now accurately quantified from new satellite missions. Much less is known about the magnitude of the energy flows within the climate system and at the Earth surface, which cannot be directly measured by satellites. In addition to satellite observations, here we make extensive use of the growing number of surface observations to constrain the global energy balance not only from space, but also from the surface. We combine these observations with the latest modeling efforts performed for the 5th IPCC assessment report to infer best estimates for the global mean surface radiative components. Our analyses favor global mean downward surface solar and thermal radiation values near 185 and 342 Wm?2, respectively, which are most compatible with surface observations. Combined with an estimated surface absorbed solar radiation and thermal emission of 161 and 397 Wm?2, respectively, this leaves 106 Wm?2 of surface net radiation available globally for distribution amongst the non-radiative surface energy balance components. The climate models overestimate the downward solar and underestimate the downward thermal radiation, thereby simulating nevertheless an adequate global mean surface net radiation by error compensation. This also suggests that, globally, the simulated surface sensible and latent heat fluxes, around 20 and 85 Wm?2 on average, state realistic values. The findings of this study are compiled into a new global energy balance diagram, which may be able to reconcile currently disputed inconsistencies between energy and water cycle estimates.  相似文献   

12.
A new scheme for the estimation of daily global solar radiation over sloped topography in China is developed based on the Iqbal model C and MODIS cloud fraction. The effects of topography are determined using a digital elevation model. The scheme is tested using observations of solar radiation at 98 stations in China, and the results show that the mean absolute bias error is 1.51 MJ m~(-2) d~(-1) and the mean relative absolute bias error is 10.57%. Based on calculations using this scheme,the distribution of daily global solar radiation over slopes in China on four days in the middle of each season(15 January,15 April, 15 July and 15 October 2003) at a spatial resolution of 1 km × 1 km are analyzed. To investigate the effects of topography on global solar radiation, the results determined in four mountains areas(Tianshan, Kunlun Mountains, Qinling,and Nanling) are discussed, and the typical characteristics of solar radiation over sloped surfaces revealed. In general, the new scheme can produce reasonable characteristics of solar radiation distribution at a high spatial resolution in mountain areas,which will be useful in analyses of mountain climate and planning for agricultural production.  相似文献   

13.
China's Feng Yun 3(FY-3) polar orbiting satellites are set to become an important source of observational data for numerical weather prediction(NWP),atmospheric reanalyses,and climate monitoring studies over the next two decades.As part of the Climate Science for Service Partnership China(CSSP China) program,FY-3 B Microwave Humidity Sounder 1(MWHS-1) and FY-3 C MWHS-2 observations have been thoroughly assessed and prepared for operational assimilation.This represents the first time observations from China's polar orbiting satellites have been used in the UK's global NWP model.Since 2016,continuous data quality monitoring has shown occasional bias changes found to be correlated to changes in the energy supply scheme regulating the platform heating system and other transient anomalies.Nonetheless,MWHS-1 and MWHS-2 significantly contribute to the 24-h forecast error reduction by 0.3% and 0.6%,respectively,and the combination of both instruments is shown to improve the fit to the model background of independent sounders by up to 1%.The observations from the Microwave Radiation Imager(MWRI) also are a potentially significant source of benefits for NWP models,but a solar-dependent bias observed in the instrument half-orbits has prevented their assimilation.This paper presents the bases of a correction scheme developed at the Met Office for the purpose of a future assimilation of MWRI data.  相似文献   

14.
Fengyun-3 E(FY-3E),the world’s first early-morning-orbit meteorological satellite for civil use,was launched successfully at the Jiuquan Satellite Launch Center on 5 July 2021.The FY-3E satellite will fill the vacancy of the global early-morning-orbit satellite observation,working together with the FY-3C and FY-3D satellites to achieve the data coverage of early morning,morning,and afternoon orbits.The combination of these three satellites will provide global data coverage for numerical weather prediction(NWP)at 6-hour intervals,effectively improving the accuracy and time efficiency of global NWP,which is of great significance to perfect the global earth observing system.In this article,the background and meteorological requirements for the early-morning-orbit satellite are reviewed,and the specifications of the FY-3E satellite,as well as the characteristics of the onboard instrumentation for earth observations,are also introduced.In addition,the ground segment and the retrieved geophysical products are also presented.It is believed that the NWP communities will significantly benefit from an optimal temporal distribution of observations provided by the early morning,mid-morning,and afternoon satellite missions.Further benefits are expected in numerous applications such as the monitoring of severe weather/climate events,the development of improved sampling designs of the diurnal cycle for accurate climate data records,more efficient monitoring of air quality by thermal infrared remote sensing,and the quasicontinuous monitoring of the sun for space weather and climate.  相似文献   

15.
Long-term,ground-based daily global solar radiation (DGSR) at Zhongshan Station in Antarctica can quantitatively reveal the basic characteristics of Earth’s surface radiation balance and validate satellite data for the Antarctic region.The fixed station was established in 1989,and conventional radiation observations started much later in 2008.In this study,a random forest (RF) model for estimating DGSR is developed using ground meteorological observation data,and a highprecision,long-term DGSR dataset is constructed.Then,the trend of DGSR from 1990 to 2019 at Zhongshan Station,Antarctica is analyzed.The RF model,which performs better than other models,shows a desirable performance of DGSR hindcast estimation with an R~2 of 0.984,root-mean-square error of 1.377 MJ m~(-2),and mean absolute error of 0.828 MJ m~(-2).The trend of DGSR annual anomalies increases during 1990–2004 and then begins to decrease after 2004.Note that the maximum value of annual anomalies occurs during approximately 2004/05 and is mainly related to the days with precipitation (especially those related to good weather during the polar day period) at this station.In addition to clouds and water vapor,bad weather conditions (such as snowfall,which can result in low visibility and then decreased sunshine duration and solar radiation) are the other major factors affecting solar radiation at this station.The high-precision,longterm estimated DGSR dataset enables further study and understanding of the role of Antarctica in global climate change and the interactions between snow,ice,and atmosphere.  相似文献   

16.
In this study,the clear sky hourly global and net solar irradiances at the surface determined using SUNFLUX,a simple parameterization scheme,for three stations(Gaize,Naqu,and Lhasa) on the Tibetan Plateau were evaluated against observation data.Our modeled results agree well with observations.The correlation coefficients between modeled and observed values were > 0.99 for all three stations.The relative error of modeled results,in average was < 7%,and the root-mean-square variance was < 27 W m 2.The solar irradiances in the radiation model were slightly overestimated compared with observation data;there were at least two likely causes.First,the radiative effects of aerosols were not included in the radiation model.Second,solar irradiances determined by thermopile pyranometers include a thermal offset error that causes solar radiation to be slightly underestimated.The solar radiation absorbed by the ozone and water vapor was estimated.The results show that monthly mean solar radiation absorbed by the ozone is < 2% of the global solar radiation(< 14 W m 2).Solar radiation absorbed by water vapor is stronger in summer than in winter.The maximum amount of monthly mean solar radiation absorbed by water vapor can be up to 13% of the global solar radiation(95 W m 2).This indicates that water vapor measurements with high precision are very important for precise determination of solar radiation.  相似文献   

17.
东亚地区云和地表反照率对硫酸盐直接辐射强迫的影响   总被引:9,自引:3,他引:9  
王喜红  石广玉 《气象学报》2002,60(6):758-765
文中利用区域气候模式深入探讨了东亚地区云及地表反照率对硫酸盐直接辐射强迫的影响 ,同时定量估算了东亚地区云区气溶胶的直接辐射强迫 ,讨论了硫酸盐对地表和大气短波辐射平衡产生的不同影响。研究表明 :云对气溶胶的直接辐射强迫具有很强的减弱作用 ,这种减弱作用不仅取决于云覆盖份数 ,而且取决于云的光学厚度。就区域平均而言 ,文中模拟的东亚地区气溶胶直接辐射强迫为 - 0 .0 97W /m2 ,占总直接辐射强迫的 10 .4%左右。表明云对硫酸盐直接辐射具有很强的减弱作用 ,在估算其总的直接辐射强迫时 ,云区的贡献不可忽视。较高的地表反照率会减弱硫酸盐的直接辐射强迫 ,而较低地表反照率则会增加硫酸盐的辐射强迫。硫酸盐气溶胶对大气辐射平衡影响非常小 ,但对地表辐射平衡产生重要影响 ,影响程度与大气几乎一致。  相似文献   

18.
Summary Thin plate smoothing splines incorporating topographic dependence were used to interpolate daily global solar radiation in the Bavarian forest ecosystem monitoring network, with the degree of data smoothing determined by minimizing the generalized cross validation. A simple cross validation method was used to discuss the spatial distribution of mean relative errors at 18 forest climate stations. The results show that, from this network 14%–30% mean relative errors can be expected for most of these forest climate stations in summer, and 20%–30% mean relative errors can be found at a few of forest climate stations in winter. Time-averaging can reduce these interpolation errors. In this network a mean relative error of 10% can be expected for weekly and biweekly mean solar radiation at most of forest climate stations in summer. Large errors are related to low radiation amount under heavy cloud cover. Mean relative errors increase as daily global solar radiation decreases. Received April 20, 1999 Revised January 20, 2000  相似文献   

19.
晴天地表太阳辐射的参数化   总被引:2,自引:0,他引:2  
讨论了晴天地表太阳总辐射和地表太阳净辐射瞬时值的参数化方法。首先利用辐射传输模式和中纬度夏季标准大气廓线,分谱带计算晴天各种大气条件下地表反射率取定值时的地表太阳总辐射,并把所得的结果作为标准资料,提出参数化方案。然后将地表反射率的影响作为误差项进行订正,从而得到各种地表反射率条件下的晴天地表太阳净辐射的计算方法。该方法的拟合精度较高,拟合值与辐射模式标准值的平均相对误差在0.3%以下。该参数化公式可以用于大尺度数值模式中地表辐射平衡的计算,以期达到地表辐射平衡计算与模式积分同步进行的目的。  相似文献   

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