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121.
122.
大气环流的奇偶对称性(Ⅰ)理论依据和气候特征 总被引:1,自引:0,他引:1
文中使用奇偶对称分析方法,利用观测资料对全球环流的奇偶对称分量的分布做了分析,指出奇偶分布的气候特征及其时间演变能反映南北半球海陆差异带来的影响,揭示大气对辐射加热响应的时间尺度、环流的波动结构及全球环流季节性调整等一些特征。 相似文献
123.
七月大气环流对南极海冰异常的响应 总被引:2,自引:0,他引:2
本文用一个全球大气九层谱模式,模拟了七月份南极两个不同海区海冰区异常对大气环流的影响。主要讨论了大气环流对南极海冰异常存在的局地性的及全球性的响应。细致分析了二个区域极冰异常导致的南北半球低频波列分布的差异,以及它们对热带区域及亚洲季风区降水、越赤道气流的不同影响。最后则依据我们的模拟结果,讨论了南极海冰异常影响全球大气环流的动力学机制。 相似文献
124.
在冀北丰宁、沽源、赤城一带的上侏罗统火山岩中发现有不同形态的铁质及玻璃质微球粒。经电镜扫描及外貌结构构造的鉴定,显示有熔融、碰撞、逸气、旋纹、冷疑、收缩等特征;经电子探针及X射线粉晶衍射分析,认为是宇宙尘。对其进行研究不仅有重要的地质意义,而且有找矿意义。 相似文献
125.
G. A. Herbert R. C. Schnell H. A. Bridgman B. A. Bodhaine S. J. Oltmans G. E. Shaw 《Journal of Atmospheric Chemistry》1989,9(1-3):17-48
The second Arctic Gas and Aerosol Sampling Program (AGASP-II) was conducted across the Alaskan and Canadian Arctic in April 1986, to study the in situ aerosol, and the chemical and optical properties of Arctic haze. The NOAA WP-3D aircraft, with special instrumentation added, made six flights during AGASP-II. Measurements of wind, pressure, temperature, ozone, water vapor, condensation nuclei (CN) concentration, and aerosol scattering extinction (bsp) were used to determine the location of significant haze layers. The measurements made on the first three flights, over the Arctic Ocean north of Barrow and over the Beaufort Sea north of Barter Island, Alaska are discussed in detail in this report of the first phase of AGASP II. In the Alaskan Arctic the WP-3D detected a large and persistent region of haze between 960 and 750 mb, in a thermally stable layer, on 2, 8, and 9 April 1986. At its most dense, the haze contained CN concentrations >10,000 cm–3 and bsp of 80×10–6 m–1 suggesting active SO2 to H2SO4 gas-to-particle conversion. Calculations based upon observed SO2 concentrations and ambient relative humidities suggest that 104–105 small H2SO4 droplets could have been produced in the haze layers. High concentrations of sub-micron H2SO4 droplets were collected in haze. Ozone concentrations were 5–10 ppb higher in the haze layers than in the surrounding troposphere. Outside the regions of haze, CN concentrations ranged from 100 to 400 cm–3 and bsp values were about (20–40)×10–6 m–1. Air mass trajectories were computed to depict the air flow upwind of regions in which haze was observed. In two cases the back trajectories and ground measurements suggested the source to be in central Europe. 相似文献
126.
Summary The accuracy of the electrochemical ozone sonde, type OSR, has been estimated by analysing tandem ozone soundings of the balloon-borne electrochemical ozone sonde OSR at the Lindenberg Observatory from May to November 1982. A negative bias, though not significant, has been observed above about 28 km for soundings having high single correction factors. Random errors are at their minimum just above the level of the maximum of ozone partial pressure, and reach their maximum in the troposphere. Except at heights above about 28 km the random error of ozone sondes is a factor 2 to 3 times less than the error of the short Umkehr method. Provided that soundings with too high correction factors are neglected, the ozone sonde OSR has an accuracy comparable to that of other Brewer type sondes.The maximum amount of information on the vertical ozone distribution can be drawn from sonde measurements in the lower stratosphere. A study is underway to improve the sensitivity of the sonde OSR and thus to further enhance its reliability. 相似文献
127.
The lunar barometric tide has been determined with reasonable accuracy, on an annual and seasonal basis, at five stations on the mainland of New Zealand and at three of the outlying islands. The determinations show that in the New Zealand region the lunar tide has a larger amplitude and smaller phase than might have been expected from previously available southern-hemisphere results. In general, the seasonal variation of phase in the New Zealand region conforms to the currently recognised global pattern, with the J-season phase greater than that of the D-season. Similarly, the amplitude variation tends to support the suggestion that, south of latitude 30°S, the D-season amplitude is greater than that of the J-season. Approximate tests are introduced and used to assess the statistical significance of some of the apparent differences in amplitude and phase made evident by the analysis. These assessments indicate that although many of the apparent differences may be attributed to sampling fluctuations, the main regional anomalies in amplitude and phase are likely to be real. It is suggested that these anomalies may indicate a significant regional input of tidal energy to the atmosphere (at the lower boundary) from the Pacific oceanic tide. 相似文献
128.
Syed Nizamuddin 《Pure and Applied Geophysics》1984,122(1):86-88
Potential gradients were measured in the valley of the Simhachalam hills and near the top. They were found to be higher at the top than in the valley, where they increased in the forenoon. It was the reverse at the top of the hills. The valley winds were found to play an important role in the variation of potential gradient. 相似文献
129.
首次报道齐依求金矿中微球粒的发现,对微球粒形态特征、表面及断面结构、物理特性、矿物组成、化学成分进行分析测试,并就其成因作了初步探讨,认为属宇宙成因。 相似文献
130.