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731.
福建省冬季暴雨过程及其环流特征 总被引:4,自引:0,他引:4
利用福建省66个气象观测站1960年12月至2008年2月的暴雨资料,分析了福建冬季暴雨的时空特征及主要影响天气系统。结果表明,冬季暴雨主要发生在闽西;福建冬季暴雨主要是南支槽东移、切变线维持和冷空气南下影响所致;冬季暴雨的产生与充沛的水汽、对流不稳定和辐合上升运动密切相关,但大气层结比汛期暴雨要稳定得多;冬季暴雨异常与500 hPa大气环流和赤道中东太平洋海温异常关系密切,它们可能主要通过大气环流的改变引起福建冬季暴雨异常。 相似文献
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本文利用云南省跨断层短水准测量资料,提出且证实了一个新的观点:在地震平静期点位基本稳定的条件下,地震前不同测点间的不同变化是一种地震前兆信息。 相似文献
735.
Xin-Fa Deng Ji-Zhou He Jian-Ying Xu Ying-Ping Ding 《Astrophysics and Space Science》2009,323(3):273-279
From the approximately volume-limited Luminous Red Galaxy (LRG) sample of the Sloan Digital Sky Survey Data Release 6 (SDSS
DR6), we construct three LRG samples with different g-r color, which have the nearly same number density, to investigate the
color dependence of clustering properties of LRGs. It is found that the blue galaxies have a more filamentary distribution
than red galaxies, and that the bluest LRGs preferentially inhabit the dense groups and clusters. But in three LRG samples
with different u-g color, we do not observe the tendency for clustering properties of LRGs to significantly change with color.
We preferentially conclude that the clustering properties of LRGs are not strongly correlated with colors. 相似文献
736.
The first complete charge-coupled device (CCD) light curves in B and V bands of the short-period binary system, RV Psc, are presented. It is found that the light curves of RV Psc are symmetric and belong to the EW type rather than the EA type as described in the 4th edition of the GCVS. Photometric solutions were derived by using the 2003 version of the Wilson–Devinney (W-D) method. It is shown that RV Psc is a marginal contact system (f=5.8%±6.6%) with a mass ratio of q=0.5978±0.0096. The temperature difference between both components is only 17 K. Analysis of the O-C curve suggests that the period of RV Psc shows a long-term continuous decrease at a rate of dP/dt=?5.89×10?8 days/year. The long-time period decrease, the marginal-contact configuration, and the astrophysical parameters of the binary system, all suggest that it is a newly formed marginal contact binary from a case A mass transfer and will evolve into a normal overcontact binary. 相似文献
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Chuiyu Lu Bo Zhang Xin He Guoliang Cao Qingyan Sun Lingjia Yan Tao Qin Tianchen Li Zepeng Li 《Ground water》2021,59(1):90-99
MODFLOW is one of the most popular groundwater simulation tools available; however, the development of lake modules that can be coupled with MODFLOW is lacking apart from the LAK3 package. This study proposes a new approach for simulating lake - groundwater interaction under steady-state flow, referred to as the sloping lakebed method (SLM). In this new approach, discretization of the lakebed in the vertical direction is independent of the spatial discretization of the aquifer system, which can potentially solve the problem that the lake and groundwater are usually simulated at different scales. The lakebed is generalized by a slant at the bottom of each lake grid cell, which can be classified as fully submerged, dry, and partly submerged. The SLM method accounts for all lake sources and sinks, establishing a governing equation that can be solved using Newton's method. A benchmarking case study was conducted using a modified model setup in the LAK3 user manual. It was found that when there is a sufficient number of layers at the top of the groundwater model, SLM simulates an almost identical groundwater head as the LAK3-based model; when the number of layers decreases, SLM is unaffected while LAK3 may be at a risk of giving unrealistic results. Additionally, the SLM can reflect the relationship between the simulated lake surface area and lake water depth more accurately. Therefore, the SLM method is a promising alternative to the LAK3 package when simulating lake - groundwater interaction. 相似文献