【作者】 文小航；

【导师】 尚可政；

【作者基本信息】 兰州大学 ， 气象学， 2008， 硕士

【摘要】 地球-大气系统的辐射收支对大气和海洋的热力及环流状况起着决定性的作用,塑造了地球气候的主要特征,到达地面的太阳辐射量是影响气候和环境最重要的物理量之一。因此对地面太阳辐射的研究具有特别的意义,能够帮助了解地面辐射变化对环境、区域气候的变化带来的影响。本文利用中国大陆122个常规地面辐射观测站1961-2000年地面观测太阳辐射的逐日总辐射、直接辐射、散射辐射和净辐射资料,首先对资料进行质量控制阈值检验,在剔除错误数据和缺测数据的基础上,按照中国地理气候区域的特征并考虑年总辐射,将中国大陆划分为5个不同的辐射区域(东北区;西北区;青藏区;中南区,华东区),系统地分析研究了这40年来我国太阳辐射时空分布状况和变化趋势。分析了各区近40年来总辐射、直接辐射、散射辐射量的年代际距平变化;然后结合全国729个常规气象观测站点1961-2000年逐日云量资料和能见度资料提出了一种估算一年中任何一天太阳总辐射的计算模型,并作误差分析;最后结合全国729个站点逐日平均气温,194个站点逐日最高气温和最低气温分析地面接收到的太阳辐射和气温之间的相关关系,获得了一些创新性的研究成果,归纳起来主要有:(1)中国大陆5个辐射气候区域的总辐射和直接辐射量在1961-1990年之间呈下降趋势,在上世纪80年代达到最低值,以青藏高原西南部地区降幅最明显;在1991-2000年总辐射和直接辐射量有回升趋势,其中青藏高原地区回升最显著,但均未达到历史最高水平。这与全球范围内出现的Dimming和Brightening现象相对应。东北区;西北区;青藏区;中南区;华东区各区总辐射近40年来年均下降率分别为-1.24%/10a,-1.66%/10a,-1.60%/10a,-1.89%/10a和-1.93%/10a。各区近40年来散射辐射量除东北无明显变化外,南疆和青藏高原有降低趋势,而南方有略微增加趋势。(2)通过对云量的分析发现西北地区低云量略增加,而其他地区低云量和总云量都有不同程度的下降趋势,各区总云量近40年来年均下降率为:-2.99%/10a,-1.68%/10a,-3.10%/10a,-1.17%/10a和-1.01%/10a,低云量变化率为:-1.51%/10a,4.46%/10a,-1.47%/10a,-0.89%/10a和-0.75%/10a。全国能见度在1961-2000年间不断下降,与辐射下降趋势相吻合。初步认为总辐射在1980年以前的下降原因是大气颗粒物增多造成,但1980年后能见度年际变幅不是影响辐射年际变幅的主要原因。(3)全国平均气温在1961-2000年间呈上升趋势,40年来平均上升0.84℃,年均日较差呈显著下降趋势,40年来全国平均下降0.92℃。逐日平均气温、最高气温、最低气温与总辐射、直接辐射、散射辐射和净辐射显著正相关。而年平均的各气温要素与年总辐射呈反相关的变化趋势,说明大气气溶胶和温室气体的增加,一方面引起到达地面的太阳辐射下降,另一面减少长波射出,使近地面气温上升。春季接收辐射大于秋季,但是春季气温和秋季相差不大,这是气温对太阳响应滞后的结果(4)基于云量和水平能见度提出的总辐射估算模型能较好的估算出太阳总辐射量。对中国大陆16个不同的代表站用多元回归拟合求得拟合值与实测值结果进行比较与统计检验表明:总辐射拟合值与实测值之间相关显著(相关系数为0.76-0.92),拟合方法的均方根偏差RMSE为3.6 MJ/m~2·d;平均偏差MBE为0.003MJ/m~2·d;平均绝对偏差MABE为2.72 MJ/m~2·d;平均绝对误差MAPE为19.10%。本方法的优点是简单实用,仅需要目测当地云量和能见度就能快速估算出当日太阳总辐射量,对临近地区也能普遍适用。更多还原

【Abstract】 The radiation budget of the Earth-atmosphere system plays a crucial effect to the heat and circulation station of the atmosphere and ocean,and forms the primary properties of the Earth climate.The radiation reached to Earth is one of physic factors affecting the climate and environment.So the research of ground solar radiation has significant sense to understand the effects of ground radiation’s change to the change of environment and regional climate.Based on the data of 122 routine ground radiation observatories’ Global radiation, Direct radiation,Scatter radiation and net radiation from 1961 to 2000,the quality control of the data used in the study were processed by the method of limitation test, to remove all the wrong data and missing data.We divide Chinese mainland into 5 different types of radiation region.In the study,the time and spatial distribution and the change properties of the solar radiation in China during this 40 years was analyzed Then in the combination of the data of each day’s cloud cover and the visibility,a new model to calculate the solar Global radiation of any day in a year was put forwarded, and it’s tested through the error analysis.In the end,the correlation between the temperature and the solar radiation received by the ground was presented in the combination of 729 stations’ daily average temperature and 194 stations’ daily maximum and minimum temperature,and tested by the significant test.The innovated research results are as follows:(1)Global radiation and Direct radiation declined during 1961-1990,but increased during 1990 to 2000,Increasing coefficient was significant in Tibetan plateau,but solar radiations did not get to the highest values in all areas.This phenomenon is anastomosis to "Dimming" and "Brightening" in all over the word. The decline rate of Global radiation is -1.24%/10a,-1.66%/10a,-1.60%/10a, -1.89%/10a and -1.93%/10a in every area.In recent 40 years,variation of Scatter radiation was not significant in northeast China,but declined in south Xin-Jiang and Qinghai-Tibet plateau and a little bit increase in South China.(2)By using statistical analysis on cloud cover,we found that low cloud cover increased in northwest China and both total cloud cover and low cloud cover decreased in other areas.The decline rate of total cloud cover is -2.99%/10a, -1.68%/10a,-3.10%/10a,-1.17%/10a and -1.01%/10a;the variation of low cloud cover is -1.51%/10a,4.46%/10a,-1.47%/10a,-0.89%/10a and -0.75%/10a in every area.The visibility in China was declined during 1961 to 2000,the downward trend was anastomosis to Global radiation.So we concluded that the reason of Global radiation decline before 1980 was caused by increased atmospheric particles.(3)The average temperature was increased during 1961 to 2000,increasing 0.84℃in recent 40 years,the DTR was a downward trend,decreased by 0.92℃. There was a significant correlation between average temperature,High temperature, Low temperature and Global radiation,Direct radiation,Scatter radiation and Net radiation,but also has inverse correlation between temperature and radiation.It shows that the increasing of atmospheric aerosol and greenhouse gases on the one hand it cause the decreasing of surface radiation,on the other hand it prevent long wave radiation.Lead to surface temperature increase.In spring surface receive radiation more than autumn,but temperature had not changed distinctly.The disproportion of radiation-temperature is corresponding with unique geography and climate in China.(4)The operative model based on cloud cover and visibility was built to estimate daily solar radiation easily.Compared the multivariate regression fitting value with the measured value,the results for 16 representative stations in the different region showed that:the fitted solar radiation value had significantly related to the observation value(R=0.76-0.92),RMSE was 3.6 MJ/m~2·d;MBE was 0.003 MJ/m~2·d; MABE was 2.72 MJ/m~2·d;MAPE was 19.10%.by using routine observation data of cloud cover and visibility,daily solar radiation can be easily estimated.更多还原