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61.
62.
通过对1956-1996年11次厄尔尼诺现象与太阳黑子、大气环流的关系分析,发现有一定规律,用概率统计方法建立起厄尔尼诺的预报模式。 相似文献
63.
J. Kar 《Earth, Moon, and Planets》1996,73(2):187-192
Recently, the possibility of strong mass loss from an early sun has been proposed in connection with the lithium depletion problem along with early solar system problems. However, the time scale for this enhanced mass loss is uncertain. Using an empirical relation for the dependence of the Martian surface temperature on solar luminosity and surface pressure, we find that the mass loss time scale for a 1.1 M sun should be about 1 × 109 years or longer if Mars had liquid water on its surface 3.8 billion years ago. The minimum surface pressure on early Mars should be about 5 bars of CO2. 相似文献
64.
The probability distribution of the sea surface slope has been estimated using sun glitter images derived from the visible
wavelength radiometer on the Geostationary Meteorological Satellite (GMS) and surface vector winds observed by spaceborne
scatterometers. The brightness of the visible images is converted to the probability of wave surfaces which reflect the sunlight
toward GMS in grids of 0.25° × 0.25° (latitude × longitude). The slope and azimuth angle required for the reflection of the
sun's rays toward GMS are calculated for each grid from the geometry of GMS observation and location of the sun. The GMS images
are then collocated with surface wind data observed by three scatterometers. Using the collocated data set of about 30 million
points obtained in a period of 4 years from 1995 to 1999, the probability distribution function of the surface slope is estimated
as a function of wind speed and azimuth angle relative to the wind direction. The results are compared with those of Cox and
Munk (1954a). The surface slope estimated by the present method shows a narrower distribution and much less directivity relative
to the wind direction than that reported by Cox and Munk. It is expected that their data were obtained under conditions of
growing wind waves. In general, wind waves are not always developing, and the slope distribution might differ from the results
of Cox and Munk. Most of our data are obtained in the subtropical seas under clear-sky conditions. This difference in the
conditions may be the reason for the difference of slope distribution.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
65.
I. CHARVÀTOVÀ 《Surveys in Geophysics》1997,18(2-3):131-146
The time series of solar and volcanic activities have been processed to show, mostly by means of statistical characteristics, the exceptional and recurring pattern of these phenomena in the intervals of the exceptional and recurring pattern of solar motion, i.e. in the intervals of the Sun's motion along the trefoils which reoccur in steps of 178.7 years. Nearly the same sets of five sunspot cycles have been found in the latest trefoil intervals (1730–1780 and 1910–1960), their length being constant and equal to 10 years (cycles No. 15–19). The steadily attenuated volcanic activity have been pointed out in the three latest trefoil intervals. The long-term maxima of surface air temperature occured in the central decades of the trefoil intervals. The results indicate a primary role of solar motion in a causal chain of ST-relations and a need of taking the Solar System as a whole into account to explain climatic changes. The solar motion can be computed in advance. Predictive assesments, so far in form of analogies, have been made: Because the solar motion in the next decades will be chaotic, lower and longer solar cycles (with irregular length), ocurrence of huge volcanic events and a decrease of global surface air temperature can be expected. 相似文献
66.
T. G. Forbes 《地球物理与天体物理流体动力学》2013,107(1-4):15-36
Abstract The magnetic energy stored in the corona is the only plausible source for the energy released during large solar flares. During the last 20 years most theoretical work has concentrated on models which store magnetic energy in the corona in the form of electrical currents, and a major goal of present day research is to understand how these currents are created, and then later dissipated during a flare. Another important goal is to find a flare model which can eject magnetic flux into interplanetary space. Although many flares do not eject magnetic flux, those which do are of special importance for solar-terrestrial relations since the ejected flux can have dramatic effects if it hits the Earth's magnetosphere. Three flare models which have been extensively investigated are the emerging-flux model, the sheared-arcade model, and the magnetic-flux-rope model. All of these models can store and release magnetic energy efficiently provided that rapid magnetic reconnection occurs. However, only the magnetic-flux-rope model appears to provide a plausible mechanism for ejecting magnetic flux into interplanetary space. 相似文献
67.
68.
为配合大型太阳设备西部选址工作,研制了一架现代日晕光度计(Sky Brightness Monitor,SBM).前期实验对日晕光度计性能进行了测试,同时积累了云南部分址点的日晕数据.资料分析结果显示,轿子雪山正午前后的日晕水平最低可至日面中心强度百万分之几的量级(蓝波段).这表明该日晕光度计内部杂散光水平已达到了国际同类产品的标准.日晕光度计的内部杂散光源主要来自两部分:镜筒前端中性滤光片(ND4)固定套圈的边缘衍射(视场靠内区域)和镜筒内置光阑的边缘衍射(视场靠外区域).针对后者进行的变换光阑孔径大小试验结果证实,适当缩小光阑孔径可有效减小数据中视场靠外区域的衍射光干扰. 相似文献
69.
Jian-Xia Cheng Cheng Fang Peng-Fei Chen Ming-De Ding Department of Astronomy Nanjing University Nanjing 《中国天文和天体物理学报》2005,5(3):265-272
Sympathetic coronal mass ejections (CMEs) usually occur in different active regions connected by interconnecting magnetic loops, while homologous CMEs occur within the same active region with an almost the same background magnetic field, and so are similar in shapes. Two sympathetic CMEs erupted within 3 hours on 2002 May 22, originating from the same active region, AR 9948. Their multi-wavelength data were collected and analyzed. It is suggested that emerging flux triggered the occurrence of the first CME and the corresponding flare, the reconnection inflow of which in turn triggered the eruption of the second CME. Based on the fact that the two sympathetic CMEs have many similarities, in their shapes, their low-lying dimming areas, etc., we tentatively propose, for the first time, the phenomenon of sympathetic homologous CMEs. 相似文献
70.