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1.
探讨了在无辐射站的情况下,使用效果较好的经验公式(Q q)=(Q q)0(a bs)来间接计算黔西南州太阳总辐射,在拟合经验系数时,考虑黔西南州的气候特点和地理位置等,采用昆明和贵阳的实测辐射值拟合经验系数;经验系数的确定不但与气候带有关,还与季节有关,因而拟合了12个月的经验系数,计算精度大大提高。并计算黔西南州1970—2005年逐年逐月太阳总辐射值,发现其太阳总辐射值在4217.18~4660.54M Jm-2之间,太阳能资源位于贵州省前列,具有较大的开发利用潜力。  相似文献   

2.
陈胜军  郭力民 《气象》1982,8(12):23-23
关于太阳总辐射的气候学计算,已有许多人做了这方面的工作。在经验公式的时段划分问题上,有的是全年配制一个公式,有的是每季配一个公式,还有的是每月配制一个公式。而广东省太阳辐射候总量的气候学计算则是以自然季节来划分经验公式所取的时段的。萧文俊等人曾指出:经验公式的系数因气候条件的差异而发生变化。因此,按年或季来配制公式虽然方便,但是不能反映出各时段的气候特点,计算精度就会受到一定影响。按月配制公式,工作量会增加很多。在对我省太阳辐射月总量进行计算时,考虑到既要提高计算精度,又要尽可能减少工作量,我们用聚类分析法来解决经验公式的时段划分问题。  相似文献   

3.
福建省散射辐射的计算方法及其分布特征   总被引:2,自引:0,他引:2  
林正云 《气象》1994,20(4):10-14
提出了综合考虑日照百分率和总云量来计算散射辐射的公式。将散射辐射D除以日照百分率S1,称其为净散射辐射。同时求出各月及年的净散射辐射与当地天文辐射的比值和总云量的相关系数r。各月与年的相关系数均为正值,且r均大于r0.01。在此基础上建立计算散射辐射的经验公式:D=S1Qoe^a+bN,式中D为散射辐射;S1为日照百分率;Qo为天文辐射;N为总云量;a和b为经验系数。使用该经验公式求得福建省所有市  相似文献   

4.
太阳辐射是重要的农业资源和立地环境,目前主要依靠公式计算获取,因此选择适当的计算方法是必要的。论文通过比较国内外5种太阳总辐射气候学计算结果与太阳辐射观测值,其方差平均值大小顺序为:孙治安经验公式〈朱志辉经验公式〈左大康经验公式〈翁笃鸣经验公式〈埃斯屈朗方程,因此选择孙治安经验公式Q=Qn[c+(1-c)s]为浙江省太阳总辐射的最佳计算公式。分析计算结果表明,浙江省年太阳总辐射在4332.19~4870.66MJ·m-2之间,东部沿海多,北部、西部少;多年平均年变化值呈双峰型变化,7月最大,12月或1月最小,6月份为一相对低值;以杭州站为代表分析其气候变化,发现太阳总辐射平均每10a下降20MJ·m-2。浙江省年光合有效辐射在2060.16—2310.07MJ·m-2之间;多年平均年变化呈单峰型或弱双峰型变化,分布特征与太阳总辐射类似,年际间光合有效辐射波动较小,趋势变化持平。  相似文献   

5.
平凉地区秋季旱涝气候特征   总被引:2,自引:1,他引:1  
选用平凉地区7站30年(1960~1989年)秋季的气象资料,引入张宝先生提出的干燥指数公式,进而得出秋季旱涝指数的经验公式;从划分秋季旱涝标准着手,分析了平凉地区秋季旱涝的气候特征。  相似文献   

6.
东北地区玉米气候生产潜力时空分布特征   总被引:4,自引:0,他引:4  
利用旋转经验正交函数和功率谱等方法分析了1961~2007年东北地区玉米光温生产潜力和气候生产潜力的时间变化趋势及区域特征。结果表明,东北地区玉米光温生产潜力呈显著的上升趋势;气候生产潜力呈下降趋势,但变化趋势不显著。玉米光温生产潜力和气候生产潜力均存在7~9年的显著周期变化。玉米气候生产潜力还存在5年和3年左右的显著周期;东北玉米光温生产潜力呈西南区域与东北区域相反的空间趋势分布,生产潜力的高值区位于辽宁大部、吉林西部和黑龙江西南部,低值区位于东北的东部地区;东北玉米气候生产潜力的高值区位于东北的东南部,低值区位于东北的西部。  相似文献   

7.
2008年1月起,新疆各级气象部门执行新的短期气候预测业务规定.针对新规定中要求的预测内容和评分标准,本文介绍了利用Excel电子表格进行短期气候预测评分工作的方法.并以伊犁地区2008年4月份气温、降水趋势预测为实例,详细介绍了用Excel电子表做短期气候预测评分的具体步骤、公式意义及结果生成.  相似文献   

8.
根据山西省107个气象站1981—2012年10个历时的年最大降水量资料,利用Gumbel分布函数调整频率,得出雨强(i)-历时(t)-重现期(p)关系表。在此基础上,首先采用无约束的非线性优化求解方法拟合得到误差最小的暴雨强度公式参数,然后对暴雨强度公式参数进行分组拟合试验,得到另外一组暴雨强度公式,以最小误差的暴雨强度公式结果为标准,最终给出合理的暴雨强度公式参数空间分布,其结果可用于缺乏气象观测站的区域根据下垫面和气候分区特点构建暴雨强度公式。  相似文献   

9.
本文在上文基础上,进一步探讨了地面有效辐射的经验计算方法。根据Берлянд,М.Е.和Берлянд,Т.Г.理论公式推导出简化的经验公式。该式结构合理,使用方便。计算全国101个站的有效辐射与[1]的计算结果基本一致。文中还给出了全年各季代表月份地面有效辐射的全国分布图,并对地面有效辐射的年变化进行了分型和区划。我国有效辐射分布的一般规律是高原大于平原;干燥区大于湿润区;北方地区夏季大于冬季;青藏高原东南部地区冬季大于夏季;江淮流域的广大地区全年变化很小。  相似文献   

10.
根据月平均气温、月降水量推算蒸散量   总被引:1,自引:0,他引:1  
因为从月平均气温、月平均降水量推算蒸散量的桑斯威特(Thornth-waite)公式适用范围比较小,假定降水量、蒸散量和最大水汽压成比例,可以求得适用于更大范围的经验公式。为了检验这些经验公式的精度,把从这些公式计算的蒸散量,P-E比与实测的蒸散量,气候状况等进行比较。  相似文献   

11.
尹宏 《气象学报》1957,28(2):101-107
本文首先用北京和南京的总辐射及日照记录,比较了几种计算总辐射经验公式的精确程度,然后用哈蒙等人设计的图解,由日照求出中国东部总辐射的分布。  相似文献   

12.
潘守文 《气象学报》1991,49(1):75-79
本文给出的计算地球日射总量公式,在极圈内精度与Milankovitch公式一致,在极圈外仍具有极高的精度,而Milcnkovitch公式则不能应用。据此讨论了气候变化中地球轨道参数对辐射项的影响。结果表明,距今最近一次间冰期和冰期的日射分布特征与地质考古发现的新事实基本吻合,因而有可能在气候的未来变化中对辐射项进行预测。  相似文献   

13.
Variations in terrestrial insolation, induced by perturbations of the earth's orbital parameters, are calculated for different geographical latitudes for ±100000 yr and in detail for the modern period between A.D. 1800–2100. The calculations show that short-period insolation variations occur against a background of secular variation, with an amplitude which can be comparable in magnitude to that of the 300-yr secular trend. For comparison we calculate the secular trends of insolation for Milankovich's caloric half-years for the period ±100000 yr with high time resolution. The nature of secular and short-term insolation changes is discussed for different latitudinal circles during future centuries. We conclude that orbitally-induced variations of insolation with periods of 18.6, 11.9, 5.9, 4.0, and 2.7 yr will perturb the radiation regime at the upper atmospheric boundary.  相似文献   

14.
The sea roughness effect on insolation and sun rays reflection for different sun heights above the horizon and unclouded sky is considered. Numerical assessments for albedo, insolation, and absorbed radiation are received for Stokes waves. Normal ray falling at the wave crest is suggested. The ray trace approach is used that allowed to take into account such effects as the dependence of albedo on the wave tilt, double light reflection from neighboring wave crests and the trough shading by the crest. It is concluded that the main roughness effect on the radiative balance is the insolation increasing and albedo diminishing at large wave steepness when the sun height above the horizon is less than 40°.  相似文献   

15.
贵州高原起伏地形下日照时间的时空分布   总被引:1,自引:0,他引:1       下载免费PDF全文
由于坡度、坡向和地形之间相互遮蔽等局地地形因子的影响, 实际起伏地形下的日照时间与水平面上的日照时间有一定差异。该文建立了一种基于数字高程模型 (DEM) 的起伏地形下日照时间的模拟方法, 计算了起伏地形下贵州高原100 m×100 m分辨率日照时间的时空分布。结果表明:坡度、坡向、地形遮蔽对日照时间的影响较大, 实际起伏地形下日照时间的空间分布具有明显地域特征。1月太阳高度角较低, 坡度、坡向的作用非常明显, 地形遮蔽面积较大, 日照时间的空间差异较多, 日照时间为16~142 h, 最大值约为最小值9倍; 7月太阳高度角较高, 地形遮蔽面积相对较小, 日照时间的空间差异相对较少, 日照时间为133~210 h, 最大值为最小值1.6倍, 但由于7月日照时间相对较多, 局地地形对日照时间影响仍明显。4月、10月日照时间及其变化幅度介于1月和7月之间。  相似文献   

16.
Summary The solar insolation at any point on the Earth can be expressed in terms of the latitude and longitude of that point and the parameters of the Earth's orbit. The derivation of such an equation is given here. One purpose of the equation is to gain theoretical insights into how the insolation varies on the time scales of the Milankovitch cycles. The most easily attained insights are that neither the main pacemaker of the ice agese, nor Milankovitch's precession indexe sin appear as terms in the equation (e is the eccentricity of the Earth's orbit and is the argument of perihelion.) Obliquity does appear. These results are already well-known, but are easily derived when the insolation is formulated as given here. The equation also suggests expressing the Earth's albedo in the same form as the insolation. When this is done a term which looks likee sin can be made to appear, for example, multiplied by an albedo coefficient and lagged in phase. However, the term is small, of the order ofe 2. Besides theoretical insights, a second purpose of the equation is to provide a convenient formula for computing insolation when using numerical climate models. Its usefulness to this end is yet to be established.With 3 Figures  相似文献   

17.
大同市空气污染对太阳辐射的影响   总被引:1,自引:1,他引:1       下载免费PDF全文
根据大同市辐射、日照条件变差、烟幕日数增多等事实,利用大同市1963—1987年地面实测的太阳辐射资料分析了大同空气污染对太阳辐射的影响及其长期变化情况。结果表明,到达地面的太阳辐射量的减弱与空气中混合污染物的影响有较密切的关系;空气污染对太阳辐射量减弱的逐年变化情况,与混浊度因子的变化有很好的相关关系。  相似文献   

18.
Short-term variations of the elements representing the Earth's motion around the Sun and its rotation have been analyzed over the last 6000 years using 1-year steps. Their low-frequency part is compared first to the values obtained from a secular theory of the planetary long-term motion showing that they can be considered reliable enough to represent adequately the motion of the Earth over the last 5000 years. Spectral analysis of these values shows that the main periodicities are 2.67, 3.98, 5.26, 5.93, 7.9, 9.8, 11.9, 14.7, 15.8, 29, 42, 61, 122, 165 and 250 years for the eccentricity as well as for the climatic precession, with an additional component at around 930 years for the eccentricity and around 840 years for the climatic precession. Periodicities at 2.67, 3.8, 5.9, 8.0, 9.3, 11.9, 14.7, 18.6, 29, 135, 250 and 840 yr are also shown for the obliquity. Spectral analyses of the daily July mid-month insolation at 65°N show essentially the same periodicities as the climatic precession and the obliquity, i.e. 2.67, 3.98, 5.92, 8.1, 11.9, 15.7, 18.6, 29, 40, 61 and around 900 years. Finally a wider analysis of the insolation pattern was performed related to the large periodicity band of the insolation time series for the solstices and the equinoxes for 7 different latitudes. In equatorial latitudes the insolation variance is largely explained by precession. But precession dominates everywhere with the obliquity signal being stronger at polar latitudes at the solstices. The amplitudes of the insolation change at these frequencies is of the order of 0.2 Wm–2 at the maximum. Offprint requests to: A Berger  相似文献   

19.
Summary For astronomical seasons, Rubincam insolation deviations at latitude 65° N varied from 218.50 Wm−2 to 225.75 Wm−2 (3%). The periodicity of the insolation cycles varied from 36.7 Kyr to 44.7 Kyr (20%) due to phase shift. Phase shift of insolation variations can induce asymmetry of the insolation cycles, permitting rapid melting and prolonged glaciation of ice sheets to occur. For instance, an abnormal decrease of the insolation frequency during the longer period of glacial interval would prolong glaciation into deep ice age. In this study, we apply Rubincam’s insolation equations to investigate the phase shift effect of insolation variations on climate change. Using complex transforms of the changing insolation, we have detected a phase modulation signal in the insolation variations. As a result, an especially new and interesting series of the phase-related insolation pulsation is established. The phase modulated insolation is then introduced as a forcing function into energy balance climate models. Results of model computations shed new insights into the spectrum of the paleoclimatic proxy-data. It is shown that phase modulation of the insolation may provide an appropriate and complete external forcing mechanism to which the climate system would respond. The 100 Kyr cycle of the frequency modulation of the Rubincam’s insolation variations does seem adequate to change the climate. Received July 16, 1997 Revised May 18, 1998  相似文献   

20.
Solar surface insolation (SSI) represents how much solar radiance reaches the Earth??s surface in a specified area and is an important parameter in various fields such as surface energy research, meteorology, and climate change. This study calculates insolation using Multi-functional Transport Satellite (MTSAT-1R) data with a simplified cloud factor over Northeast Asia. For SSI retrieval from the geostationary satellite data, the physical model of Kawamura is modified to improve insolation estimation by considering various atmospheric constituents, such as Rayleigh scattering, water vapor, ozone, aerosols, and clouds. For more accurate atmospheric parameterization, satellite-based atmospheric constituents are used instead of constant values when estimating insolation. Cloud effects are a key problem in insolation estimation because of their complicated optical characteristics and high temporal and spatial variation. The accuracy of insolation data from satellites depends on how well cloud attenuation as a function of geostationary channels and angle can be inferred. This study uses a simplified cloud factor that depends on the reflectance and solar zenith angle. Empirical criteria to select reference data for fitting to the ground station data are applied to suggest simplified cloud factor methods. Insolation estimated using the cloud factor is compared with results of the unmodified physical model and with observations by ground-based pyranometers located in the Korean peninsula. The modified model results show far better agreement with ground truth data compared to estimates using the conventional method under overcast conditions.  相似文献   

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