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41.
The global distribution of the ground-level temperature variance and its long-term variations have been investigated on the basis of the monthly mean temperature anomalies, obtained from ground-based and sea-borne meteorological observations from 1896 to 1990. Particular characteristics of the large-scale structure of the temperature variance have been found. There are three pronounced maxima in the global distribution of the temperature variance: in Central Siberia (60°75°N and 70° 120°E), North America (60°75°N and –170°–120°E) and the Antarctica (50°65°S and –60°10°E, where and are the geographic latitude and longitude, respectively) and there are two minima: over the Atlantic and Pacific Ocean areas. The minimum over the Pacific is not as pronounced, as over the Atlantic. The spatial pattern of the ground-level temperature variance is, on the whole, stable, the positions of the zones of extrema remaining practically unchanged over a long time interval. These results indirectly corroborate the mechanism of solar impact on the properties of the low atmosphere by the modulation of the flux of galactic cosmic rays. The mechanism accounts for the spatial distribution of the temperature variance as a result of combined effect of solar activity and ocean. Long-term variations of the Siberian maximum of the ground-level temperature variance agree with the changing duration of the sunspot cycle, in contrast to the North American maximum.  相似文献   
42.
Tree ring studies are usually used to determine or verify climatic factors prevailing at a given place or region that may cause tree-ring width variations. Few studies are dedicated to the solar phenomena which may underlie these tree-ring width variations. Furthermore, it is known that some terrestrial phenomena are influenced by short- and long-time scale solar variability. An optical and computational method was set up and applied to tree samples (Araucaria angustifolia from Santa Catarina State in Southern Brazil) in order to obtain a growth ring width mean chronology. Spectral analysis is used for the search of periodicities, by maximum entropy and iterative regression methods. The results evidenced several embedded signals at periods which may be related to solar activity variations. Cross-correlation analysis between sunspot number and tree-ring data was performed and a lag of zero year was obtained. From our work, it seems that the tropical conifer species Araucaria angustifolia may be a good choice for studies on Sun-Earth relationships and their regional effects.  相似文献   
43.
SCL与中国东部气候年代际变化   总被引:3,自引:2,他引:1  
据宇地磁耦合原理,利用太阳黑子周期长度(SCL)的变化及其与地磁场(文中主要考虑地热)的关系,模拟计算并重建了中国东部历史时期的气温序列变化,除了个别时段外,模拟曲线与修正后的竺可桢曲线十分相似;分析了2500a来中国东部气候的年代际变化.结果表明,该曲线能较好地再现2500a来中国东部气候的冷暖变化.对竺氏曲线中有争议的几个冷暖时段,如公元150—350年的温暖期、1050—1150年的小气候适宜期等,模拟结果与后来研究者分析的结果相合.中唐至五代的气候冷暖交替变化不稳定.该曲线也能清晰地反映出小冰期中国东部气候各个时段的变化以及现代气候的变化趋势。  相似文献   
44.
战淑芸 《海洋预报》1997,14(4):37-43
本文对亚洲逐日西风指数与逐日太阳黑子数二者之间的变化关系进行了计算分析。结果表明,太阳活动对大气的影响,不仅在长周期变化中存在,在逐日变化过程中也同样存在。  相似文献   
45.
对比分析1957--2008年间Dst≤-100nT的强磁暴数与太阳黑子数的变化趋势,发现太阳黑子数和Dst≤-100nT的强磁暴数的变化趋势有很好的一致性。进一步统计强磁暴在太阳周不同阶段的分布后发现,同一太阳周内60%以上的强磁暴出现在下降年,但从太阳周各个阶段的平均磁暴年发生率来看,强磁暴平均年发生率最高的年份仍然是太阳活动极大年。  相似文献   
46.
近54年来辽西北地区降水与太阳黑子关系研究   总被引:3,自引:1,他引:2  
曹永强  刘佳佳  高璐 《地理科学》2015,35(8):1027-1032
根据1960~2013年辽西北地区50个雨量站逐日降水量数据和同期太阳黑子相对数数据,利用Mann-Kendall检验法对辽西北地区近54 a来的降水量变化趋势进行分析,采用Morlet小波分析技术分析了研究区降水量和太阳黑子的变化周期,并计算了相应的小波系数。结果表明:辽西北地区降水量年际变化表现为微弱的下降趋势,突变点在1996~1997年之间,突变前后降水趋势由升转降。太阳黑子与降水距平值的负相关关系显著,且存在5 a的滞后性,对降水周期影响较小,与降水量相关关系复杂。  相似文献   
47.
We give an extensive multi-wavelength analysis of an eruptive M1.0/1N class solar flare, which occurred in the active region NOAA 10044 on 2002 July 26. Our empha-sis is on the relationship between magnetic shear and flare shear. Flare shear is defined as the angle formed between the line connecting the centroids of the two ribbons of the flare and the line perpendicular to the magnetic neutral line. The magnetic shear is computed from vector magnetograms observed at Big Bear Solar Observatory (BBSO), while the flare shear is computed from Transition Region and Coronal Explorer (TRACE) 1700A images. By a detailed comparison, we find that: 1) The magnetic shear and the flare shear of this event are basically consistent, as judged from the directions of the transverse mag-netic field and the line connecting the two ribbons' centroids. 2) During the period of the enhancement of magnetic shear, flare shear had a fast increase followed by a fluctuated decrease. 3) When the magnetic shear stopped its enhancement, the fluctuated decreasing behavior of the flare shear became very smooth. 4) Hard X-ray (HXR) spikes are well correlated with the unshearing peaks on the time profile of the rate of change of the flare shear. We give a discussion of the above phenomena.  相似文献   
48.
Spectral analyses were made of derived area-index series of areas subject to extreme temperatures and precipitation as well as cross-spectral analyses of the area-index series with double sunspot cycle (Zurich) numbers. Superposed epoch analyses also were made of area-index series versus various double-sunspot cycle phases. Area series for wet and dry Junes, warm Junes, defined June drought, and warm Januaries all show statistically significant double sunspot cycle (21 year) periodicities. The 21-year cycle of above-normal June precipitation is most striking and has not received previous recognition.Journal Paper No. J-10007 of the Iowa Agric. and Home Econ. Exp. Stn., Iowa State University, Ames, IA, 50011, Project 2397.  相似文献   
49.
本文分析了第21 、22 、23 太阳活动周的上升期23 个月( 月均值) 太阳黑子资料。结果表明:太阳黑子相对数和面积南北不对称。23 周的太阳黑子相对数和面积(23 个月的平均) 高于22 周,但低于21 周。我们估计第23 周峰年为2000 年3 月或1999 年12 月。  相似文献   
50.
Can Asymmetry of Solar Activity be Extended into Extended Cycle?   总被引:1,自引:0,他引:1  
With the use of the Royal Greenwich Observatory data set of sunspot groups,an attempt is made to examine the north-south asymmetry of solar activity in the “extended” solar cycles. It is inferred that the asymmetry established for individual solar cycles does not extend to the “extended” cycles.  相似文献   
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