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101.
武辉芹  时珉  赵增保  尹瑞 《气象科技》2020,48(5):752-757
太阳辐照度与光伏电站发电功率密切相关,其预报的准确性直接影响发电功率预报的准确性。根据光伏电站太阳辐照度实况、气象站实况、WRF(Weather Research and Forecast Model)模式辐照度预报、EC细网格数值预报以及太阳理论辐照度,利用逐步回归法开展太阳辐照度预报订正研究,得到以下结论:①太阳辐照度实况与太阳理论辐照度的比值与EC细网格数值预报中气象要素的相关性优于太阳辐照度实况与气象要素的相关性;②不同时刻影响太阳辐照度的气象因子存在差异,通过逐步回归法建立不同时刻太阳辐照度预报模型;③在非晴天情况下,回归预报辐照度相对均方根误差比WRF模式预报辐照度降低10%左右,减小了辐照度预报误差。该研究成果在光伏电站的新能源数值预报服务中有一定的应用价值。  相似文献   
102.
额济纳地区苜蓿地光合有效辐射(PAR)的基本特征   总被引:14,自引:1,他引:13  
利用额济纳地区查干毛道饲草料基地(主要种植苜蓿)内2001年6~9月的辐射观测资料.对该荒漠绿洲的光合有效辐射(PAR)的月变化、日变化、极值及其所占太阳短波辐射比例ηQ的一些基本特征作了分析和讨论,并与张掖、临泽、太湖地区及美国Texas站作了比较,发现该地区PAR的夏季总量、月平均日总量及各项极值都大于前述其它站点,辐射资源十分丰富;晴天日和阴天日PAR的变化有明显的区别;对于ηQ,云和水汽、太阳辐射强度、光周期对它都有影响。  相似文献   
103.
Physical understanding of total and spectral solar irradiance variation depends upon establishing a connection between the temporal variability of spatially resolved solar structures and spacecraft observations of irradiance. One difficulty in comparing models derived from different data sets is that the many ways for identifying solar features such as faculae, sunspots, quiet Sun, and various types of “network” are not necessarily consistent. To learn more about classification differences and how they affect irradiance models, feature “masks” are compared as derived from five current methods: multidimensional histogram analysis of NASA/National Solar Observatory/Kitt Peak spectromagnetograph data, statistical pattern recognition applied to SOHO/Michelson Doppler Imager photograms and magnetograms, threshold masks allowing for influence of spatial surroundings applied to NSO magnetograms, and “one-trigger” and “three-trigger” algorithms applied to California State University at Northridge Cartesian Full Disk Telescope intensity observations. In general all of the methods point to the same areas of the Sun for labeling sunspots and active-region faculae, and available time series of area measurements from the methods correlate well with each other and with solar irradiance. However, some methods include larger label sets, and there are important differences in detail, with measurements of sunspot area differing by as much as a factor of two. The methods differ substantially regarding inclusion of fine spatial scale in the feature definitions. The implications of these differences for modeling solar irradiance variation are discussed. K.L. Harvey and S.R. Walton are deseased, to whom this paper is dedicated.  相似文献   
104.
饶俊峰  张显峰 《热带地理》2015,35(6):852-859
以香港地面站观测的AOD与WVC数据为参照,首先分析了MISR/AOD和MODIS/WVC产品的不确定性描述方法,然后在考虑二者联合不确定性的影响下,推导了辐射传输方程法估算地面太阳短波辐射的相对误差分布函数。通过统计2005―2013年香港MISR/AOD和MODIS/WVC反演值的分布情况,得出两者的联合概率密度函数,然后将AOD和WVC的联合概率密度函数作为权重函数与相对误差分布函数积分,得到对辐射传输方程法估算地面太阳短波辐射的相对误差数学期望。结果表明,夏季在太阳天顶角为0°时,使用MISR/AOD和MODIS/WVC产品估算地面太阳短波辐射的相对误差期望为3.17%,并且有90%的把握使估算结果相对误差<3.53%;不同季节不同太阳天顶角下、不同置信水平下,地面太阳短波辐射估算的相对误差大小,可为不同应用研究提供基础数据,为评估亚热带地面太阳短波辐射估算结果是否符合应用需求提供依据。  相似文献   
105.
This work investigates the spectral atmospheric transmittance due to aerosols in the urban environment of Athens during a period of one year. The spectral transmittance due to aerosols is derived using measurements of spectral direct-beam solar irradiance in the 310–575 nm spectral band. This derivation is accomplished by using a radiative transfer model for estimating the partial spectral atmospheric transmittance functions due to Rayleigh scattering, and absorption by ozone, nitrogen dioxide and water vapor. The seasonal and diurnal variation of the aerosol transmittance is investigated and the results are discussed with a view to air pollution sources, meteorological factors and topographic characteristics of the Athens basin.  相似文献   
106.
在实验室培养条件下,详细观察了披针形蜈蚣藻(Grateloupia lanceolata)早期发育过程及生活史,研究了温度与光周期、温度与光照强度的交互作用对其盘状体发育及幼苗生长的影响。结果表明:(1)披针形蜈蚣藻孢子发育类型为"间接盘状体"类型;(2)披针形蜈蚣藻生活史由单倍体的雌、雄配子体,二倍体的果孢子体和四分孢子体组成,配子体与四分孢子体形态一致,为典型的同型世代交替;(3)温度与光周期、温度与光照强度的交互作用对披针形蜈蚣藻盘状体发育及幼苗生长均有极显著影响(P0.01)。其中由温度与光周期交互实验得出:适宜披针形蜈蚣藻生长发育的温度范围为10—25°C,在温度15°C、光周期16L︰8D的条件下,盘状体相对生长速率最大[RGR=(9.902%±0.51%)/d],幼苗的相对生长速率最大[RGR=(9.569%±0.48%)/d]。温度与光照强度交互实验得出:在温度15°C、光照强度80μmol/(m~2·s)条件下,盘状体相对生长速率最大[RGR=(10.113%±0.51%)/d],幼苗的相对生长速率最大[RGR=(8.839%±0.44%)/d]。本研究为披针形蜈蚣藻的种质保存、人工育苗、规模化栽培以及可持续开发利用提供了理论依据和技术支撑。  相似文献   
107.
The new version (version 8) TOMS (Total Ozone Mapping Spectrometer) ozone and noontime erythemal ultraviolet (UV) irradiance products are used to analyze their long-term changes in this paper. It is shown that the summer UV irradiance has increased significantly from Central China to the northern and western parts of China, especially in Central China near Chongqing, Shaanxi, and Hubei provinces; whereas the UV irradiance has decreased significantly in the southern part of China, especially in South China. In July, when UV irradiance is at its maximum and hence when the most serious potential damage may happen, the results indicate an increase in the UV irradiance in Central China and the Yangtze River- Huaihe River valley and a decrease in South China and the eastern part of North China. At the same time, the total ozone amount is lower over China in summer with the most serious depletion occurring in Northeast China and Northwest China. It is found that the thinning of the ozone layer is not the main reason for the UV irradiance trend in the eastern and southern parts of China, but that the rainfall and the related cloud variations may dominate the long-term changes of the UV irradiance there. In addition, the future UV irradiance trend in China is also estimated.  相似文献   
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