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1.
我国太阳日总辐射计算方法的研究 总被引：13，自引：0，他引：13
对全国23个站点的日照时数、日最高气温、日最低气温、太阳日总辐射量等气象要素实测资料进行统计分析,利用回归分析法建立了以日照百分率和气温日较差为主要相关因子的各地日总辐射估算模型。结果表明：除了高原站拉萨以外,推算模型的复相关系数均介于0．80～0．93之间,拟合效果较好。在春、夏季使用独立的季节模型有一定的必要性,该方法适用于我国各地太阳日总辐射的推算, 相似文献
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B. Aksoy 《Theoretical and Applied Climatology》1997,58(1-2):71-77
Summary Since measured solar radiation data in Turkey have rather high random errors, sunshine duration data covering the period from 1960 through 1994 from 34 stations in Turkey were taken to derive estimates of monthly mean global solar radiation by a quadratic correlation. The least square linear regression method was applied for trend analysis. Significant negative trends of the annual means were observed with 71 percent of the stations A 3.44 percent decrease in global solar radiation was observed over the last 35 years in Turkey. The decrease in solar radiation is an indication of increased air pollution, as statistical parameters show that Turkey is rapidly expanding economically, and thus air quality has deteriorated correspondingly.With 3 Figures 相似文献
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河北省太阳总辐射经验系数两种气候学计算方法的比较分析 总被引：1，自引：0，他引：1
利用河北省周边8个日射站逐月日照百分率资料和太阳总辐射资料,采用最小二乘法拟合经验系数a、b,然后分别通过纬度分区和反距离权重插值两种方法得到河北省142个测站的经验系数a、b,并据此求出河北省内四个具有辐射观测数据台站的总辐射值,对比分析了实测值与不同经验系数下总辐射估算值之间的差异。结果表明：纬度分区和反距离权重插值两种方法所建立的太阳总辐射量估算公式的模拟精度总体差别不大,但采用纬度分区法所得的经验系数,在计算太阳辐射年总量时与实际观测值更为接近,因此建议采用纬度分区法计算河北省各地太阳总辐射量。 相似文献
4.
Solar radiation is an essential and important variable to many models. However, it is measured at a very limited number of meteorological stations in the world. Developing method for accurate estimation of solar radiation from measured meteorological variables has been a focus and challenging task. This paper presents the method of solar radiation estimation using support vector machine (SVM). The main objective of this work is to examine the feasibility of SVM and explore its potential in solar radiation estimation. A total of 20 SVM models using different combinations of sunshine ratio, maximum and minimum air temperature, relative humidity, and atmospheric water vapor pressure as input attributes are explored using meteorological data at 15 stations in China. These models significantly outperform the empirical models with an average 14 % higher accuracy. When sunshine duration data are available, model SVM2 using sunshine ratio and air temperature range is proposed. It significantly outperforms the empirical models with an average 26 % higher accuracy. When sunshine duration data are not available, model SVM19 using maximum temperature, minimum temperature and atmospheric water vapor pressure is proposed. It significantly outperforms the temperature-based empirical models with an average of 18 % higher accuracy. The remarkable improvement indicates that the SVM method would be a promising alternative over traditional approaches for estimation of solar radiation at any locations. 相似文献
5.
运用数据集群技术，在黄河流域建立了用日照百分率拟合太阳总辐射的不同时空尺度估算式，对比分析了不同数据集群下总辐射的拟合精度。利用逆距离加权插值法，将获得的黄河流域及其周边35个日射站1~12月总辐射拟合的经验系数进行空间内插，获得了黄河流域1~12月总辐射拟合经验系数的空间分布。结合黄河流域及其周边164个常规气象站日照百分率观测资料，对黄河流域1960~2000年太阳总辐射进行了计算，分析了其气候变化的时空分布规律。结果表明:黄河流域近年来太阳总辐射呈下降趋势，在季节上主要表现在夏季和冬季。 相似文献
6.
为深入了解气象探测环境对气温观测数据的影响,利用2017年北京市观象台（54511）与南海子站（A1274）逐小时地面气象要素数据,分析两站气温差异以及因站点探测环境导致的日照、风速和降水对两站气温差异的影响。结果表明：2017年两站气温差异较明显,年平均气温54511站比A1274站高0.75℃;两站逐月平均气温54511站全年高于A1274站,两站差值7月最低为0.60℃,9月最高为1.09℃;两站平均日最高气温较接近,平均日最低气温差异较大,54511站较A1274站高1.24℃;两站气温的日变化特征相似,呈单峰分布,54511站气温日较差低于A1274站。两站小时气温差值随着日照时长和强度的增加而增加,短波辐射效应最强的10-14时和长波辐射效应最强的19-23时两站气温差值与当日白天直接辐射曝辐量的相关系数分别为0.459和0.601;水平风速对两站气温差值的影响较大。水平风速超过5 m·s-1时,两站气温差小于0.1℃;当水平风速不超过1 m·s-1时,两站观测气温差值达到1.28℃;降水天气下两站的气温差值小于非降水天气,出现降水时次54511站平均气温仅比A1274站高0.2℃。两站相距4.3 km,气候均一,测站周边2 km范围内建设用地占比54511站比A1274站高约30%,植被占比低28%,水体占比相差不大。另外,54511站附近的五环路具有低反射率和高热容的特征,白天能够吸收太阳辐射储存较多的热量,这些热量在夜间释放,可能是两站探测环境对太阳辐射吸收的差异决定了两站温差受太阳辐射和风速的影响较大,而受降水影响较小。 相似文献
7.
我国太阳总辐射气候学计算方法的再讨论 总被引：24，自引：2，他引：24
根据我国建站时间在30a以上的辐射资料以及对应的地面站日照资料，在分析太阳总辐射统计特征的基础上，讨论了总辐射气候学计算公式中a、b系数的地理分布和季节变化特征，分析了辐射气候学计算的可能误差，得到了用日照资料估算总辐射的误差范围。结果表明，太阳总辐射月总量接近正态分布特征；总辐射气候学计算公式中的a、b系数具有较明显的时空变化特征，需按不同月份确立；通过逐年观测资料计算各基本站a、b系数，再由内插求得无辐射资料测站的a、b系数，进而计算无辐射资料站的辐射总量，其误差在可接受的范围内。 相似文献
8.
O. Senkal 《Russian Meteorology and Hydrology》2018,43(1):49-55
This study creates a database on incoming solar radiation using artificial neural networks (ANN) and information on altitude, air temperature and pressure, water vapor pressure, dry air density, water vapor density, and mixing ratio obtained at five weather stations in Turkey. The coefficients of correlation of the calculation results for three regimes of air density with observational data for the training sample (2000–2001) are 99.24%, 99.82%, and 96.67%; for the testing sample (2002), 95.97%, 82.32%, and 95.11%. These values indicate that the usage of artificial neural networks and data of at-mosphere parameters is a correct and effective method for estimation of solar radiation and creation solar databases. 相似文献
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为了便于研究水气界面辐射传输、水下光辐照度以及湖泊储热量，探讨太湖地区总辐射概况及其变化。文章在概述当前太阳总辐射气候学计算的主要方法及公式基础上，采用最小二乘法，利用上海、南京、杭州3站1961~2000年共40年的历史资料，确定各站的经验系数，然后内插求出太湖无锡地区的经验系数。由此推导出太湖无锡地区太阳总辐射的气候学计算公式，并利用无锡站日照百分率资料求算出近40年到达地面的太阳实际总辐射。然后利用太湖站1998年的太阳总辐射实测资料检验其公式精度，确定公式的可信度。最后对计算值进行分析，阐述了近40年来太湖无锡地区太阳总辐射的变化特征及其原因。研究结果表明:无锡地区太阳总辐射呈下降趋势，而这种下降主要是由于大气中悬浮物增加所致；总辐射年内变化趋势基本上与天文辐射相吻合，但又存在差异，这主要与梅雨的存在有关。 相似文献
12.
几种水平面太阳总辐射量计算模型的对比分析 总被引：2，自引：1，他引：1
利用中国区域1961-1999年39 a间98个常规气象观测数据,建立6个模型分别以天文辐射、干洁大气总辐射和湿洁大气总辐射为起始数据,进行太阳辐射日总量的模拟,对比分析了6个水平面太阳总辐射量计算模型的性能.结果表明:在三种起始数据中,干洁大气总辐射和湿洁大气总辐射均能较好地体现宏观地势对太阳辐射空间分布的影响,以湿洁大气总辐射为起始数据的计算模型拟合精度相对较高.对6个水平面太阳总辐射量计算模型的对比分析发现:2个以日照百分率为主导因子,气温日较差为修正项的综合模型拟合误差最小,精度最高;经典的日照百分率模型次之,但其模型系数最稳定可靠;3个气温日较差模型拟合效果最差.最终选用经验系数稳定、拟合精度较高的日照百分率模型,制作了2001年中国水平面太阳辐射日总量空间分布图. 相似文献
13.
Isaac Moradi Richard Mueller Richard Perez 《Theoretical and Applied Climatology》2014,116(3-4):661-669
Solar radiation is an important variable for studies related to solar energy applications, meteorology, climatology, hydrology, and agricultural meteorology. However, solar radiation is not routinely measured at meteorological stations; therefore, it is often required to estimate it using other techniques such as retrieving from satellite data or estimating using other geophysical variables. Over the years, many models have been developed to estimate solar radiation from other geophysical variables such as temperature, rainfall, and sunshine duration. The aim of this study was to evaluate six of these models using data measured at four independent worldwide networks. The dataset included 13 stations from Australia, 25 stations from Germany, 12 stations from Saudi Arabia, and 48 stations from the USA. The models require either sunshine duration hours (Ångstrom) or daily range of air temperature (Bristow and Campbell, Donatelli and Bellocchi, Donatelli and Campbell, Hargreaves, and Hargreaves and Samani) as input. According to the statistical parameters, Ångstrom and Bristow and Campbell indicated a better performance than the other models. The bias and root mean square error for the Ångstrom model were less than 0.25 MJ m2 day?1 and 2.25 MJ m2 day?1, respectively, and the correlation coefficient was always greater than 95 %. Statistical analysis using Student’s t test indicated that the residuals for Ångstrom, Bristow and Campbell, Hargreaves, and Hargreaves and Samani are not statistically significant at the 5 % level. In other words, the estimated values by these models are statistically consistent with the measured data. Overall, given the simplicity and performance, the Ångstrom model is the best choice for estimating solar radiation when sunshine duration measurements are available; otherwise, Bristow and Campbell can be used to estimate solar radiation using daily range of air temperature. 相似文献
14.
The study presents a critical assessment of the possibility of global solar irradiation computation by using air temperature instead of sunshine duration with the classical Ångström equations. The reason for this approach comes from the fact that, although the air temperature is a worldwide measured meteorological parameter, this is rarely used in solar radiation estimation techniques. More than that, the literature is very silent concerning the testing of such models in Eastern Europe. Two new global solar irradiation models (to be called AEAT) related to solar irradiation under clear sky conditions and having the minimum and maximum daily air temperature as input parameters were tested and compared with others from the literature against data measured at five stations in Romania in the year 2000. The accuracy of AEAT is acceptable and comparable to that of the models which use sunshine duration or cloud amount as input parameters. Since temperature-based Ångström correlations are strongly sensitive to origin, the approach for AEAT as a tool for potential users is presented in detail. Additionally reported is a new method to increase the generality of AEAT concerning the extension of the geographical application area. Based on overall results it was concluded that air temperature successfully substitutes sunshine duration in the estimation of the available solar energy. 相似文献
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Yoshimitsu Masaki Tsuneo Kuwagata Yasushi Ishigooka 《Theoretical and Applied Climatology》2010,100(3-4):283-297
We have developed a method for estimating hourly global solar radiation (GSR) from hourly sunshine duration data. This procedure requires only hourly sunshine duration as the input data and utilizes hourly precipitation and daily snow cover as auxiliary data to classify time intervals into six cases according to weather conditions. To obtain hourly GSR using a simple algebraic form, a quadratic function of the solar elevation angle and the sunshine duration ratio is used. Daily GSR is given by a sum of hourly GSRs. We evaluated the performance of the newly developed method using data obtained at 67 meteorological stations and found that the estimated GSR is highly consistent with that observed. Hourly and daily root-mean-square misfits are approximately 0.2 MJ/m2/h (~55 W/m2) and 1.4 to 1.5 MJ/m2/day (~16 to 17 W/m2), respectively. Our classification of weather conditions is effective for reducing estimation errors, especially under cloudy skies. Since the sunshine duration is observed at more meteorological stations than GSR, the proposed new method is a powerful tool for obtaining solar radiation with hourly resolution and a dense geographical distribution. One of the proposed methods, GSRgrn, can be applicable to hourly GSR estimations at different observation sites by setting local parameters (the precipitable water, surface albedo, and atmospheric turbidity) suitable to the sites. The hourly GSR can be applied for various micrometeorological studies, such as the heat budget of crop fields. 相似文献
17.
EVALUATION OF TEMPERATURE RECORDS OBTAINED BY AWS IN HAINAN PROVINCE AND ADJUSTMENT OF CLIMATOLOGICAL TIME SERIES 总被引：1，自引：0，他引：1
Based on the parallel air temperature data of automatic sounding and manual observations at 16
weather stations in Hainan province from 2004 to 2005, a comparative analysis and evaluation is made for
validity according to relevant standards. The results indicate that there are daily and seasonal differences
between temperature observations recorded by automatic weather stations (AWSs) and with conventional
methods. The reasons for the differences are the systematic error, the sensitivity of the two types of
instruments to the environmental temperature change, the difference of the observation time and the effect
of solar radiation. Because the long-range data were obtained from manual observation, an empirical
conversion formula between the temperature records obtained by the instruments is provided for
continuous use of the climate data after the changes in instruments. 相似文献
18.
Estimating sunshine duration from other climatic data by artificial neural network for ET0 estimation in an arid environment 总被引：1，自引：0，他引：1
Ali Rahimikhoob 《Theoretical and Applied Climatology》2014,118(1-2):1-8
Sunshine duration data are desirable for calculating daily solar radiation (R s) and subsequent reference evapotranspiration (ET0) using the Penman–Monteith (PM) method. In the absence of measured R s data, the Ångström equation has been recommended by the Food and Agriculture Organization (FAO) of the United Nations. This equation requires actual sunshine duration that is not commonly observed at many weather stations. This paper examines the potential for the use of artificial neural networks (ANNs) to estimate sunshine duration based on air temperature and humidity data under arid environment. This is important because these data are commonly available parameters. The impact of the estimated sunshine duration on estimation of R s and ET0 was also conducted. The four weather stations selected for this study are located in Sistan and Baluchestan Province (southeast of Iran). The study demonstrated that modelling of sunshine duration through the use of ANN technique made acceptable estimates. Models were compared using the determination coefficient (R 2), the root mean square error (RMSE) and the mean bias error (MBE). Average R 2, RMSE and MBE for the comparison between measured and estimated sunshine duration were calculated resulting 0.81, 6.3 % and 0.1 %, respectively. Our analyses also demonstrate that the difference between the measured and estimated sunshine duration has less effect on the estimated R s and ET0 by using Ångström and FAO-PM equations, respectively. 相似文献
19.
Ren Li Lin Zhao Tonghua Wu Yongjian Ding Yufei Xin Defu Zou Yao Xiao Yongliang Jiao Yanhui Qin Linchan Sun 《Theoretical and Applied Climatology》2013,113(3-4):573-583
Global solar radiation is of great significance to the balance of ground surface radiation, the energy exchange between the Earth’s surface and atmosphere, and the development of weather and climate systems in various regions. In this study, the monthly global radiation recorded at 23 stations over the Qinghai–Tibetan Plateau (QTP) was utilized to estimate global solar radiation (Q) from sunshine duration and to obtain improved fits to the variation coefficients of the monthly Angström–Prescott model (APM). The modeling results were evaluated by calculating the statistical errors, including mean bias error, mean absolute error, root mean square error, and mean relative error. We demonstrate that the monthly Q values can be predicted accurately by APM over the QTP. We also assess the variations of Q values at 116 meteorological stations by APM over the QTP during 1961–2000. The analysis shows that the annual mean sunshine duration amounted to more than 3,000 h over the whole plateau, implying promising prospects for economic applications of solar energy. During the past 40 years, the mean global solar radiation has been relatively high in the western QTP, extending northward to the Inner Mongolian Plateau. Although its decadal variations in the QTP and surrounding regions were inconsistent, the anomaly values of global solar radiation were generally positive during the 1960s and 1970s, indicating that the QTP’s global solar radiation has increased during those periods. The anomaly values were negative during the 1980s and 1990s, showing that the plateau’s global solar radiation has decreased during those periods. Global solar radiation over the QTP is negatively proportional to latitude but positively proportional to altitude and relative sunshine duration. Three factors, the sunshine duration, latitude, and altitude, exert great influence on global surface radiation, of which sunshine duration is most significant. A high-variation-coefficient zone of global solar radiation occurred in the western part of the QTP but, on average, the variation coefficient of the plateau’s global solar radiation was only 0.031, suggesting that the variation in global radiation was relatively stable over the whole QTP. 相似文献
20.
使用2006年7月-2007年6月沪宁高速公路沿线梅村和仙人山站附近的逐分钟路面温度、气温、湿度、风向、风速、降水气象资料, 分析了梅村和仙人山不同季节和不同天气状况下路面温度的日变化特征。结果表明:不同季节路面温度和气温具有明显的日变化;日出至日落时段,路面温度与气温有较大差异。在此基础上,应用逐步回归方法建立了梅村和仙人山最高和最低路面温度统计模型, 得出最低路面温度模型模拟结果与实况的变化趋势接近,误差绝对值不超过2℃, 具有很好的实际应用价值; 而最高路面温度模型在一定程度上模拟结果偏差较大,实际应用中需进行适当修订。 相似文献