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961.
The CRA-Interim trial production of the global atmospheric reanalysis for 10 years from 2007 to 2016 is carried out by the China Meteorological Administration (CMA) in 2017. The structural characteristics of the horizontal shear line over the Tibetan Plateau (TPHSL) based on the CRA-Interim datasets are examined by objectively identifying the shear line, and compared with the analysis results of the European Centre for Medium-Range Weather Forecasts (ECMWF)the European Center (ECMWF) reanalysis data (ERA-Interim). The case occurred at 18UTC on July 5, 2016. The results show that both of the ERA-Interim and CRA-Interim datasets can well reveal the circulation background and the dynamic and thermal structure characteristics of TPHSL, and they have shown some similar features. The middle and high latitudes at 500 hPa are characterized by500hPa present the circulation situation of 相似文献
962.
Impact of tropical cyclone development on the instability of South Asian High and the summer monsoon onset over Bay of Bengal 总被引:2,自引:0,他引:2
Guoxiong Wu Suling Ren Jianmin Xu Dongxiao Wang Qing Bao Boqi Liu Yimin Liu 《Climate Dynamics》2013,41(9-10):2603-2616
This paper analyzes the evolution of the South Asian High (SAH) during and after the development of tropical cyclone Neoguri over the South China Sea (SCS) in mid-April 2008, the formation of tropical storm Nargis over the Bay of Bengal (BOB) in late April, and the Asian summer monsoon onset, as well as their interrelationships. Numerical sensitivity experiments are conducted to explore the underlying mechanism responsible for these seasonal transitions in 2008. It is demonstrated that strong latent heating related with tropical cyclone activities over the SCS can enhance the development of the SAH aloft and generate zonal asymmetric potential vorticity (PV) forcing, with positive vorticity advection to its east and negative advection to its west. Following the decay of the tropical cyclone, this asymmetric forcing leads to instability development of the SAH, presenting as a slowly westward-propagating Rossby wave accompanied by a westward shift of the high PV advection. A strong upper tropospheric divergence on the southwest of the SAH also shifts westward, while positive PV eddies are shed from the high PV advection and eventually arrives in the southern BOB. Such synoptic patterns provide favorable pumping conditions for local cyclonic vorticity to develop. The latent heating release from the cyclogenesis further intensifies the upper-layer divergence, and the lower and upper circulations become phase locked, leading to the explosive development of the tropical cyclone over the southern BOB. Consequently, a tropical storm is generated and the BOB summer monsoon commences. 相似文献
963.
玉溪空气负氧离子变化特征分析 总被引:6,自引:1,他引:5
利用2008~2011年玉溪市9县区及主要旅游景点14台大气负氧离子自动测报系统适时观测数据,使用相关分析、灰度分析、回归分析、GIS空间分析等方法,分析空气中负氧离子变化规律;参照世界卫生组织制定的空气负氧离子等级标准,对玉溪市8县1区空气负氧离子等级进行区划。结果表明玉溪市空气负氧离子浓度有明显的日变化特征,早晨6~7点最高,下午4~5点最低,然后又逐渐升高;有森林地区空气负氧离子浓度明显高于无林地区;湖泊、瀑布等水体所在区域空气负氧离子浓度明显高于无水体区域。 相似文献
964.
利用1960—2020年京津冀83个气象观测站常规观测资料,统计分析了京津冀高温热浪日数、频次、有效积温分布特征及变化规律。结果表明:1) 气候态上,京津冀高温热浪日数、频次和有效积温在空间上均呈现南多(强)北少(弱)的分布特征,大值区均位于39°N以南。2) 京津冀地区高温热浪具有2—5 a显著的短振荡周期,同时也具有“多—少—多—少”的年代际变化特征;高温热浪日数、频次和有效积温均出现了3次突变点,并且第一次和第二次突变较第三次突变明显。3) 对比两次高温热浪日数集中偏多期发现,最近一个偏多集中期(1996—2005年)相对于上一个(1960—1972年)表现为北增南减的特征;对比两次偏少集中期发现,最近一个偏少集中期(2006—2020年)相对于上一个(1973—1995年)表现为中南部整体增加的特征,且高温热浪日数大于4 d的影响区域均呈扩大的态势。 相似文献
965.
The analysis of the protein and carbohydrate in P-POM (Plankton and Particulate Organic Matter) samples collected from the fishing ground in Minnan-Taiwan Bank in five voyages (April, June, July, August and November, 1988) shows that the protein and carbohydrate contents and amounts in samples from four stations (501, 401, 301, 201) along the coast and another four stations (404, 304, 403, 204) south and southeast of the shoal were higher than those in April and November, indicating that this phenomenon is related to the upwelling in the two regions in summer . 相似文献
966.
用富里叶分析提取垂直形变信息,是值得进一步研究的课题。本文主要讨论了两个问题:1)采样点间距与可能得到的富氏系数的最高阶数;2)如何获取合理的富氏系数。 相似文献
967.
Luo Fa-Long Bao Zheng Zhao Xiao-Peng 《Oceanic Engineering, IEEE Journal of》1992,17(4):320-325
A neural network for implementing the Marcos `propagator' bearing estimation algorithm is presented. It is shown both analytically and by simulations that this neural network is guaranteed to be stable and to provide the results arbitrarily close to the accurate propagator operator and the orthogonal projection operator on the noise subspace within an elapsed time of only a few characteristic time constants of the network. The parameters such as the interconnection strengths and bias currents of this proposed network can be obtained from the cross-spectral matrix without any computations 相似文献
968.
黄沅 《地球科学与环境学报》1997,(Z1)
本研究继哥白尼“日心说”理论,用一种新天体演化论揭示金星逆转是视运动,金星的真正运动是在内能释放、磁场减弱;体积增大、自转速率减慢;旋转轴趋于直立、公转轨道接近正圆;从自转天体向无自转天体(惰性天体)的演化过程。研究认为.天体是在物质聚集下形成,能量释放中发生演变(衰亡),所有的天体都将遵循这种规律。故本研究以水星向同步自转天体演化,月球恰是颗同步自转天体,金星向无自转天体演化为据,论证了金星自转是正转而不是逆转,同时通过模拟实验也证明这一结论的正确性,这都充分说明金星逆转违背了哥白尼体系(Copernicansystem),而传统以地球为中心的认识应该废弃。 相似文献
969.
LUXue-mei BAOJi-gang 《中国地理科学(英文版)》2004,14(1):82-89
Despite the considerable literatures defined what Ecotourism is or should be, it is experiencing various practices with different features. Now the term “Ecotourism” is almost applied to all tourism activities which are based on nature. Faced to the flooding of those unqualified Ecotourism, it is of great necessity to put forward professional claim. The present writer holds that the key to the realization of rigorous Ecotourism chiefly lies in the relationships among the different interest groups involved in it. So the focus of this paper is just on giving a special analysis to the interest relations between those stakeholders which include local government, tour-operators, local residents and eco-tourists, and thus helping to find out what wrong is in those unqualified Ecotourism and the roots of those problems. 相似文献
970.
Liu Zong-li Hao Xiang-liang Li You-gang Mei Bao 《Chinese Astronomy and Astrophysics》1981,5(3):322-328
Nova Cygni 1978 was observed from October 11 to December 23, 1978 at the Beijing Observatory with the grating spectrograph attached to the Naismith focus of the
Schmidt telescope. This paper gives postmaximum photographic magnitudes, identification of the spectral features, emission line structures, intensity ratios of some emission lines and the temperature of the underlying star.The main spectral lines in wavelength range
from October 11 to 30 are those of the following atoms or ions: H, FeII, NII, TiII, [0I], NIII. From November 10, lines of [0III], HeI and Hell become visible one after the other. The emission line Hα shows three components of which the most redshifted is the strongest. In turn, each component is split into a number of secondary peaks. Temperature of the underlying star increases with decline of the nova brightness. The upper limit of temperature may be 120000 K. 相似文献