Variation Trend of Total Solar Radiation in Nujiang Basin in Recent 30 Years

Based on the data of sunshine duration,cloud cover and relative humidity from 9 stations in 1981-2008,the spatial and temporal distribution and change trend of total solar radiation in river valley basin of Nujiang were analyzed,as well as its impact factors.The results showed that annual solar radiation decreased obviously in Nujiang basin from 1981 to 1997,with the rate of-161.1 MJ/(m2·10 a),while it went up after 1997 at the rate of 111.3 MJ/(m2·10 a).Annual total cloud cover showed significant decrease trend with the rate of 1.8%/10 a,but annual low cloud cover increased at the rate of 3.2%/10 a.Contrary to the change trend of annual solar radiation,relative humidity rose at the increase of 3.1%/10 a from 1981 to 1997 and decreased significantly at the rate of 5.6%/10 a in 1997-2008.The change of water vapor pressure was consistent with relative humility change.Low cloud cover was the main impact factor of total solar radiation and had a negative correlation with total solar radiation.

Effects of cloud,atmospheric water vapor,and dust on photosynthetically active radiation and total solar radiation in a Mongolian grassland

Photosynthetically active radiation （PAR） is an important input parameter for estimating plant produc- tivity due to its key role in the growth and development of plants. However, a worldwide routine network for sys- tematic PAR measurements is not yet established, and PAR is often calculated as a constant fraction of total solar radiation （SR）. Although the ratio of PAR to SR （PAR/SR） has been reported from many places, few studies have been performed for dry regions. The present study was therefore carried out in an arid region of Mongolia to obtain PAP-JSR and examine its dependency on sky clearness （the clearness index）, water vapor in the atmosphere and aeolian dust. Continuous measurements of PAR and SR were taken every one second using quantum and pyranometer sensors, respectively, and the readings were averaged and recorded at intervals of 30 minutes for a period of 12 months. The lowest monthly mean daily PAR/SR occurred in April （0.420）, while the highest ratio was observed in July （0.459）. Mean daily PAR/SR during plant growing season （May-August） was estimated to be 0.442, which could be useful for modeling plant productivity in the study area. The annual mean daily PAR/SR （0.435） was lower than the values reported in many previous studies. This difference could be explained with the regional variation in climate： i.e. drier climatic condition in the study area. PAR/SR was negatively correlated with the clearness index （r= -0.36, P〈0.001）, but positively with atmospheric water vapor pressure （r=0.47, P〈0.001）. The average PAR/SR was significantly lower （P=0.02） on the dusty days compared to the non-dust days. Water vapor in the atmosphere was shown to be the strongest factor in the variation of PAR/SR. This is the first study examining PAR/SR under a semi-arid condition in Mongolia.

Simple Analysis on Change Features of Total Solar Radiation in Sanjiang Plain

The yearly,quarterly,monthly and daily change tendencies of total solar radiation at Jiamusi station of Sanjiang Plain were analyzed by statistical approach such as linear tendency estimate with its hourly ground meteorological observation data during 1986 to 2015.The research results indicated that the yearly tendency rate of total solar radiation was increasing obviously,with the velocity of 114.30 MJ/(m2·10 a),while the yearly total solar radiation was 3 667.28-4 935.88 MJ/m^2,and that of March to September was higher than the average.The summer total solar radiation was the most,followed by spring,and that of all the seasons increased except autumn which decreased.The daily total solar radiation increased rapidly from the last ten days of January and reached the peak at the end of June,while it plummeted from the beginning of September to the middle ten days of November,then tended to be gentle.The amount of 5-year total solar radiation was less after 1980s while it was more before1990s,and the total solar radiation was decreasing from 1996 to 2005 but on the contrary it kept increasing in recent ten years.Over the years the earliest record of solar radiation appeared at 05:00 and the latest at 20:00,and the daily variation of the hourly solar radiation got a normal distribution centered on 12:00 to 13:00.

Relationship between Solar Activity, Total Ozone, and Solar Ultraviolet Radiation: Multifractal Analysis

We investigated the relationship between solar activity, total ozone, and solar ultraviolet B (UV-B) radiation from the perspective of multi-fractality. Fractal properties are observed in the time series of the dynamics of complex systems. To detect the changes in fractality, we performed a multifractal analysis using a wavelet transform. The changes in fractality indicated that solar activity was closely related to the total ozone and that the total ozone had a strong effect on UV-B radiation. For high solar activity, the F10.7 flux and global total ozone exhibited monofractality. The F10.7 flux and total ozone also increased, and a change from multifractality to monofractality was observed. This corresponded to the formation of the order. The strong interactions between the solar flux and ozone occur during the high solar activity. In contrast, UV-B radiation increased and showed multifractality, when fluctuations in UV-B radiation became large. For low solar activity, the F10.7 flux and total ozone exhibited multifractality, and UV-B radiation exhibited monofractality. Hence, the change in fractality of the F10.7 flux and total ozone was the opposite of UV-B radiation. A significant change in fractality for F10.7 flux and SSN, which had a significant fluctuation and a slight change in fractality for UV-B radiation, and total ozone were identified.

Influence of Solar Cycle Variations on Solar Spectral Radiation

The climatic changes associated with solar variability are largely caused by variations in total solar irradiance and solar spectral irradiance with solar activity. Thus the spectral composition of solar radiation is crucial in determining atomspheric structure. The variations in solar spectrum depend on the varied solar spots. Recently, evidence for a strong effect of solar activity on terrestrial isolation on ground-based measurements carried out by the National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Egypt (lat. 29?52'N and long. 31?20'E) during (1990-2000) were presented. Specifically, a strong increase of terrestrial isolation with sunspot number as well as a decline of the solar spectrum with solar activity was reported. Daily measurements of the solar radiation between 280 nm and 2800 nm were made by Eppley Pyranometer and Pyrheliometer instruments. The decreasing at the range 280 - 530 nm and 530 - 630 nm are represented less than 50% of direct solar radiation and the stability of at the range 630 - 695 nm and 695 - 2800 nm it mean that;some of difference radiation is appear in diffused radiation which allow to height of the temperature as much as the largest associated with significance as it appears from the curves of relative humidity.

Interannual and Decadal Variations of Surface Solar Radiation over East China in the First Half of the 20th Century

Variability and long-term trends of sunshine duration(SSD) and total cloud cover(TCC) were studied based on surface observations from 10 meteorological stations over East China in the first half of the 20 th century. The correlation coefficients between SSD and diurnal temperature range(DTR), as well as TCC, were analyzed. SSD experienced a significant increasing trend(0.16 h d-1 per decade) from 1908 to 1936, and the maximum brightening was in autumn(0.33 h d-1 per decade). The good agreement between the variability of SSD and DTR, supported by the correlation coefficient between them of 0.72, implies that the SSD measurements were reliable. TCC showed a decreasing trend(-0.93% per decade) and was significantly inversely related to SSD(-0.74), indicating the variation of SSD was attributable to changes in cloud cover. The result was obviously different to that since the 1960 s, when clouds could not account for the decadal trend of surface solar radiation in China.

Analysis of Meteorological Elements and Distribution Characters of Surface Solar Radiation in Guangxi

[Objective] The aim was to study the relation between solar radiation distribution and meteorological elements in Guangxi. [Method] Based on the observed data of solar radiation in Guangxi from 1995 to 2009, the total radiation, solar distribution and interannual changes in Guangxi were analyzed. By dint of observed data in Nanning station, the annual, seasonal and monthly changes of net radiation in Nanning and the linear relation between total radiation, solar distribution characteristics and interannual changes were discussed. [Result] The global radiation of surface solar radiation in the low latitude was higher tan the high latitude, as Beihai>Nanning>Guilin. The solar radiation changes and the seasonal changes in different places varied, as summer>autumn>spring>winter. The total radiation and solar radiation hours were consistent. The total solar radiation and the low cloud was in negative relation, but was in positive relation with sunny weather. The total solar radiation was in positive relation with ground temperature, except in winter. [Conclusion] The study provided effective theoretical basis and data reference to the study of climate and development of solar energy.

Estimation and Comparison of Solar Radiation Intensity by Some Models in a Region of Iran

Due to the increasing explanation of new energy application on a world scale and because of the reduction of environmental pollution arise from usage of solar energy in high potential regions, the necessity of solar radiation measurement in different regions of Iran is obvious. Therefore, in this study, the amount of radiation is measured by Pyranometer from beginning of February to August 2010 in Semnan (The central part of Iran), and it is compared with daily sunny hours, different estimated models of daily radiation such as Angstrom-Pryskat (Montis, Climate classification based on the Terwartha scientific map, using the results of 40 worldwide station, using the results of 9 Synoptic stations in Iran), the Maximum likelihood (using the results of 100 stations in worldwide, using the results of 9 Synoptic station in Iran). Finally, Terwartha scientific map model is proposed because of matching more with measured data on location.

化德县太阳能资源评估及光伏发电技术 可开发量的研究

利用内蒙古自治区化德县气象站1993—2022年的月太阳辐射资料、月平均日照时数和日照百分率资料,以及空间分辨率为75 m×75 m的国家基础地理数据,通过地理信息系统(GIS)技术对化德县的太阳能资源进行了分析和评估;然后考虑当地地形影响,在剔除不可开发区域和一定比例的限制开发区域后,得到了当地的光伏发电可开发区域,并对其光伏发电的技术可开发量进行了计算。研究结果表明:1)全县的多年平均水平面太阳总辐照量的平均值为1561.3 kWh/m^(2),固定式光伏发电最佳倾斜面的多年平均太阳总辐照量的平均值为2076.3 kWh/m^(2),可调节式光伏发电最佳倾斜面的多年平均太阳总辐照量的平均值为2141.6 kWh/m^(2),属于中国太阳能资源总量等级B类(即“很丰富”)。2)全县太阳能资源的空间分布总体呈现从西南到东北逐渐降低的特征,年内水平面太阳总辐照量呈正态分布特征,属于中国太阳能资源稳定度等级C类(即“一般”)。3)全县的光伏发电可利用土地面积占全县总面积的31.71%,光伏发电技术可开发量为2107.5万kW,主要集中在太阳总辐照量为2000~2200 kWh/m^(2)的区域。由此可见,化德县的太阳能资源有较大开发空间,光伏发电的开发潜力巨大。研究结果可为后续化德县的太阳能资源开发及光伏电站建设提供技术支撑和科学依据。

A method for calculating the total ozone amount in the clear skies

A new method for calculating the clear day total ozone amount was obtained by the regression analysis of the observation data of ozone,solar UV radiation, and meteorological parameters.With this method the monthly mean total ozone amounts for the year 1991 in Beijing were calculated. Generally, the calculated values agree well with the Dobson spectrophotometer measurements, the average relative deviation between them being less than 2. 2%. According to the F-test,the photochemical reactions in the atmosphere,the solar UV radiation,and the aerosols are three most important factors to affect the column total ozone amount.

Solar Radiation Climatology Calculation in China

The Angstrom-Prescott formula is commonly used in climatological calculation methods of solar radiation simulation. Fitting the coefficients is carried out using linear regression and in recent years it has been found that these coefifcients have obvious spatial variability. A common solution is to divide the study area into several subregions and ift the coefifcients one by one. Here, we use ground observation data for sunshine hours and solar radiation from 1961 to 2010. Adopting extraterrestrial radiation as the initial value, Angstrom-Prescott coefifcients are obtained by Geographically Weighted Regression at a national scale. The surfaces of solar radiation are obtained on the basis of the surfaces of sunshine hours interpolated by high accuracy surface modeling and astronomical radiation;results from spatial y nonstationary and error comparison tests show that Angstrom-Prescott coefifcients have signiifcant spatial nonstationarity. Compared to existing research methods, the method presented here achieves a better simulation effect.

西北四省太阳能资源分布与长期变化趋势分析

根据我国西北四省1978—2017年的观测数据,分析该区域太阳总曝辐量的空间分布特征,绘制太阳能资源区划图,并分析了以往研究中未涉及的太阳总曝辐量长期变化趋势。结果表明:西北四省多年平均年太阳总曝辐量为3 676~7 036 MJ/m^(2),且自西北向东南逐渐递减,高值区主要在青海大部、甘肃河西西部、宁夏大部与陕西北部。各季节太阳总曝辐量分布特征为夏季最高、春秋季次之、冬季最低。西北四省大部分地区太阳总曝辐量长期变化呈减少趋势,少部地区呈增加趋势,其中青海中西部区域减少最为明显,甘肃河西西部与武威地区、陕北部分地区增加趋势明显。在四季中,秋季太阳总曝辐量呈减少趋势的范围最大,春季太阳总曝辐量呈增加趋势的范围最大。研究结果对掌握西北四省太阳能资源的长期变化趋势与光伏电厂长期收益及风险防范有参考价值。

石羊河流域太阳辐射总模型适用性评价及基于天气类型的模型率定研究

石羊河流域光照资源充足,太阳辐射强,准确估算其太阳总辐射对石羊河流域农业生产具有重要意义。为了对常见太阳辐射总模型在石羊河流域的模拟精度进行评价,确定适合石羊河流域太阳总辐射估算的模型,本研究基于中国农业大学石羊河实验站2014-2018年的气象数据资料,选取5种太阳总辐射模型,采用决定系数R2、平均绝对误差MAE、均方根误差RMSE、一致性指数d以及整体评价指标GPI共5个指标进行适用性评价,并进行了基于不同天气类型的太阳总辐射模型模拟与评价。结果表明:基于日照百分率、日平均温度、相对湿度的综合模型具有最佳的模拟效果;晴天天气下,三次函数型A-P模型具有最佳模拟效果;多云天气下,综合模型模拟效果最佳,提出了基于天气组合的石羊河流域太阳总辐射估算模型,为石羊河流域太阳总辐射估算提供了进一步的模型支持。

1970—2021年河池市太阳总辐射时空变化特征分析

利用1970—2021年河池市气象观测及地理信息等数据,根据太阳辐射气候学估算模型,采用统计学、 Mann-Kendall突变检验和小波分析等方法,分析河池市太阳总辐射时空变化特征。结果表明,1970—2021年河池市年太阳总辐射呈现“下降-上升”趋势,年际波动总体平稳。春、夏、秋、冬四个季节均出现“变暗”和“变亮”交替过程,但各年代际变化的趋势不同,且春夏波动较为明显。年太阳总辐射在1981年发生突变。太阳总辐射变化的主周期为30 a,且呈现“多-少”周期性震荡变化。太阳能资源时空分布不均,存在空间和季节分布差异,年平均太阳总辐射在3 665.6~4 390.7MJ·m-2之间,高值区在巴马,低值区在天峨,呈现南部向西北部逐渐减小特征。各季节太阳总辐射从大到小排到为夏季、秋季、春季、冬季。

近43年江西省太阳辐射变化特征及其影响因素研究

基于江西省20个国家站1980—2022年逐日气象数据,利用Mann-Kendall趋势检验法、Pearson相关分析法分析了太阳辐射的长期变化趋势及其与气溶胶光学厚度、整层大气水汽含量、低云量和总云量之间的关系。研究发现:1)近43年来,受气溶胶光学厚度和整层大气水汽含量显著增长的影响,江西省太阳辐射以-5.7×10^(-3) MJ m^(-2) decade^(-1)的速度下降,总云量、低云量的微弱变化对太阳辐射的影响有限;2)夏季、秋季和冬季太阳辐射分别以-24×10^(-3) MJ m^(-2) decade^(-1)、-2.4×10^(-3) MJ m^(-2) decade^(-1)、-2.8×10^(-3) MJ m^(-2) decade^(-1)的速度下降,而春季太阳辐射以11.5×10^(-3) MJ m^(-2) decade^(-1)的速度上升,其中,夏季太阳辐射的下降受气溶胶光学厚度和低云量显著增加的影响,秋、冬季太阳辐射的下降受气溶胶光学厚度显著增加的影响,春季太阳辐射的增长主要取决于总云量的显著下降;3)气溶胶光学厚度和整层大气水汽含量增加导致80%的台站太阳辐射呈下降趋势,总云量和低云量下降导致20%的台站太阳辐射呈上升趋势,而修水、赣州站太阳辐射与4个影响因素的变化趋势相同的原因还需进一步研究。

江苏省可用太阳能资源潜力评估

基于气象观测资料,分析了江苏省太阳能资源时空分布特征,从太阳能资源丰富度、资源稳定性及可利用价值3个方面分析了江苏省太阳能资源潜力;在此基础上,以单晶硅电池作为屋顶可用太阳能资源的评价参考,评估了研究区太阳能资源的应用潜力。结果表明:江苏省太阳能资源北丰南贫,资源稳定性北部优于南部,且丰富程度及稳定性的变化较为一致,从北向南逐渐减少;研究区屋顶可装光伏电池面积约1.89亿m2,年均发电量约366亿kWh。

陕西太阳总辐射的计算及分布特征

文章利用了陕西省延安、西安、安康三站逐月太阳总辐射和98站的1971—2005年月日照百分率资料,建立回归分析方程,推算并分析了全省各地逐月的太阳总辐射分布,进而分析了陕西月、季、年太阳总辐射的空间分布特征为陕北5月或6月最大,关中和陕南7月份最大,并指出了省内太阳能资源的富集区,在陕北长城沿线,渭北高原次之;为陕西省太阳能资源的开发利用及太阳辐射对陕西省气候影响的研究提供了科学依据。

新疆太阳总辐射资料的均一性检验与气候学估算式的再探讨

参照新疆105个气象台站"元数据",在对12个辐射站逐月日照百分率与月总辐射资料序列进行质量控制检验的基础上,对无效值与缺测值进行了插补订正,继而以Potter非均一性客观检验方法对资料序列进行了非均一性检测,同时以SNTH方法对产生间断的序列进行了相应的非均一化订正。在均一化的月总辐射与月日照百分率资料序列基础上,探讨了利用辐射气候学估算总辐射的最佳方案及其系数的空间差异与年变化特征。结果表明:(1)月日照百分率序列仅乌鲁木齐与伊宁站有间断现象,而月辐射资料序列间断的有乌鲁木齐、伊宁、阿勒泰、哈密、和田站,且并非都与日照百分率序列同步间断。其中,和田、阿勒泰站月辐射资料序列非均一化现象最严重;(2)月辐射序列的间断大多出现在冬半年,这可能与冬季空中气溶胶含量的突然增加有关;(3)在利用辐射气候学估算式Q=Q0(a+bS)对新疆总辐射进行估算时,采用"单站单月式"效果最佳,单站平均绝对误差为3%～8%,系数a、b具有明显的空间分布特征与季节变化特征。除伊宁站外,两者还具有显著且稳定的互补关系;(4)新疆的年总辐射分布特征为自东向西、自南向北依次递减,天山山区为低值中心。秋季纬向特征最明显,冬季次之,春季转为经向,夏季多呈"涡状",且南北疆两大盆地辐射差异小。

重庆地区太阳总辐射的气候学计算方法研究

根据重庆市沙坪坝日射站1988-2007年逐日太阳总辐射、日照百分率、低云量和水汽压等资料,采用常规统计方法分析了重庆市地面总辐射的时间变化;由太阳总辐射气候学计算原理,采用线性回归方法建立月总辐射计算公式;通过相关系数检验和回归误差分析,确定了适用于重庆地区太阳总辐射月总量的气候学推算公式;进而根据所得推算公式分别计算了各站点逐月太阳总辐射总量,分析了重庆地区四季和年太阳总辐射的空间分布特征.结果表明:日照百分率的单因子线性拟合整体效果较好,但冬季月份拟合误差较大;采用日照百分率和低云量的双因子拟合,使得冬季月份的拟合误差明显减小,显著提高了整体拟合效果.分析认为,日照百分率是重庆地区地面总辐射的主要影响因子,冬季雾日数和低云量对地面总辐射具有重要影响.重庆太阳总辐射有逐年增大的趋势,与该地区实际日照时数逐年增大而低云量逐年减少等因素有关.四季及全年太阳总辐射的区域分布以重庆地区东北部最高,东南部和西部边缘一带为低值区.

陕西省太阳辐射及其日照时数的时空变化特征

根据陕西省气象台站观测资料,分析了陕西省太阳总辐射和日照时数的时空演变特征。结果表明,陕西省太阳总辐射和日照时数呈现出一致性的从北向南递减趋势,且在渭北高原一带存在太阳总辐射和日照时数的次高值区,同时指出了陕北地区4—8月,关中、陕南地区5—8月是太阳能资源利用的最佳时期。研究结果可为进一步研究区域气候变化、指导农业生产及合理利用太阳能资源提供参考依据。