Winds and waves in the middle atmosphere at Saskatoon (52°N, 107°W), Collm (52°N, 15°E) and Badary (52°N, 105°E)

Winds data from three radar systems in the U.S.S.R. G.D.R. and Canada, which are well-spaced along the 52°N latitude circle, are used to illustrate longitudinal/regional variations in the dynamics of the upper middle atmosphere 80–97 km. Responses to the stratospheric warming of 1982/3 are noted at all three locations, but the zonal wind does not reverse at Badary, consistent with the flow there being eastward during all months of the year. Planetary wave period oscillations (2–30 days) are observed at all locations, and highly significant cross-spectral coherences exist between the three stations.     

Quasi-biennial oscillation in ionospheric parameters measured at Juliusruh (55°N, 13°E)

When seasonal variations were eliminated by evaluating 12-month running means, the ionospheric parameters foE, foF2 and hmF2 at Juliusruh (54.6°N, 13.4°E) showed large solar cycle variations. However, when further 3-yr running averages were evaluated and subtracted, QBO (Quasi-biennial oscillations) were noticed in all these parameters. Sunspot series did not reveal a QBO, but geomagnetic Ap did show a QBO. The peaks of the ionospheric QBO and QBO of Ap could be roughly compared, with lags or leads of a few months. Also, these compared roughly with the well-known QBO peaks of tropical stratospheric (50 mb) zonal winds. Similar analyses at other locations are warranted.     

Tidal winds in the radio-meteor region over Trivandrum (8.5°N, 77°E)

Wind measurements using a meteor trail radar which performed during two June solstice and three December solstice months were analysed to study the tidal winds over Trivandrum (8.5°N). The ter-diurnal (8 h) component of wind was found to be as significant as the diurnal and semi-diurnal components. The modulations in the altitude profiles of amplitude and phase of the tidal wind components are interpreted to be due to higher order tidal modes. The amplitudes and vertical wavelengths of the tidal modes observed in the meteor zone are discussed.     

Long period wind oscillations in the meteor region over Trivandrum (8°N, 77°E)

The spectra of long period wind oscillations in the meteor zone over Trivandrum are presented. The spectral amplitudes were found to be much larger during June 1984 when the QBO in the stratospheric zonal wind was in a strong easterly phase compared with June 1987 when the zonal winds at the altitude of maximum QBO were weak westerlies. Zonal wind amplitudes for periods of 15 and 5 days were found to be most significant during these two June months. The amplitudes of these two oscillations in meridional wind were found to be as large as the amplitudes in the zonal wind. The vertical wavelength in both zonal wind and meridional winds of the 15-day oscillation is very large whereas for the 5-day oscillation the vertical wavelengths were 80 and 65 km during June 1984 and June 1987, respectively. The results are discussed.     

Winds oscillations (∼ 6h–6days) in the upper middle atmosphere at Monpazier (France, 45°N, 1°E) and Saskatoon (Canada, 52°N, 107°W) in 1979–1980

The medium frequency radar (∼ 2.2 MHz) at Saskatoon has been run continuously since 1978 and the Meteor Radar at Monpazier ran continuously for ∼ 10 day intervals in most months of 1979/1980. The radars are separated by ∼ 8000 km. Because of the excellent quality of the data, spectral and harmonic analyses have been completed from ∼ 70 to 100km and oscillations with periods of ∼ 6h–6days studied.There are substantial similarities in the mean zonal winds, both with regard to magnitudes and times of seasonal reversals; also in annual and semi-annual oscillations. In general, the semi-diurnal tide has similar amplitudes, phases and vertical wavelengths : there are consistent summer (long λ) and winter (short λ) characteristics, with rapid transitions between them. Differences between the timing of these transitions and in some of the mid-season tides are discussed. The diurnal tide is less regular and of smaller amplitude at both locations, often being too small to reliably characterize at Monpazier. However, seasonal variations between summer and winter months may be discerned.In addition to the 24 and 12 h tidal oscillations, which traditionally are studied in most detail, there is clear evidence for additional osculations near 6,8, ∼ 10 and ∼ 16 h and longer periods of ∼ 2 and ∼ 5 days. The amplitudes of these are often comparable or larger than the ‘dominant’ 24 and 12 h tides. The monthly and seasonal variations of these additional oscillations are studied, as a function of height, at the two locations. There is evidence for large scale (global) and small scale (local) disturbances in the wind field.     

神秘北纬30°

在地球北纬30度附近,有许多神秘而有趣的自然现象,该区域自然谜团频频发生。在中国,神秘的北纬30度横贯整个大陆腹地,各类自然现象和奇绝景观比比皆是。同样,位于北纬30度附近的浙东新昌,各类自然现象和奇绝景观也层出不穷,让人啧喷称奇……     

360°瑞士美景

<正>MySwitzerland.com在中国,提起瑞士,有人说那儿有美丽的阿尔卑斯雪山:有人想起经历了几个世纪的传奇——瑞士手表:也有人提及带些神秘色彩的瑞士银行……的确.这个西欧中不大的袖珍小国承载了太多的传奇。来瑞士.领略自然本色和人类文明发展到极致的完美与和谐:来瑞士.在依然纯净如初的保鲜空气里为自己洗去旅居大都市的尘嚣;来瑞士.敞开心肺.深呼吸!瑞士,一个你不能擦肩而过的地方……     

挪威北纬58°以北

飞机穿过云雾。带着我向斯堪的纳维亚前进,北极囤一点点在靠近,纬度不断地爬升。北纬58度,挪威最南端,比中国最北点还要北：北纬71度10分21秒,还是挪威,欧洲大陆到此结束。     

Variations of mean winds and tides in the upper middle atmosphere over a solar cycle,Saskatoon, Canada, 52°N, 107°W

Saskatoon (52 N, 107 W) medium frequency (MF) radar data from 1979 to 1990 have been analyzed to investigate the solar activity effects on upper middle atmospheric winds and tidal amplitudes. The period of study covers two solar maxima and a solar minimum; the continuous data allow a systematic analysis of solar cycle dependence on mean winds and tides. The height region of 79–97 km sampled in the study shows an apparent but very weak dependence of mean winds and tidal amplitudes on solar activity variation. The observed features are fairly consistent with the early results reported by Sprenger and Schmindkr [(1969) J. atmos. terr. Phy. 31, 217). The mean zonal wind and the semidiurnal tidal amplitudes appear to exhibit positive and negative correlations with the solar activity, respectively; the statistical significances of these correlations are generally low. There is a biennial periodicity evident in the zonal wind oscillations but this docs not have a consistent phase relationship with the equatorial stratospheric wind oscillations (QBO). The meridional winds and the tidal amplitudes are characterized with different and quite irregular periods of oscillations (2–5 yr). The diurnal tidal variations over the solar cycle are small and irregular, although amplitudes are slightly larger during the solar minimum years.     

Semidiurnal tidal winds at Collm (52°N, 15°E) and Saskatoon (52°N, 107°W) over the decade 1978–1988

Mean winds and tides have been measured by the LF and MF radar systems at Collm and Saskatoon respectively. Semidiurnal tide amplitudes and phases near 90 km evidence very similar monthly variations. A detailed comparison of mean wind and tidal profiles (85–110 km) in the Septembers of 4 years shows some differences however, which are consistent with regional (Europe-Canada) differences in the mean background winds.     

Initial EISCAT observations of plasma convection at invariant latitudes 70°–77°

The potential of the EISCAT radar system for observing plasma convection patterns at high latitudes has been explored in a preliminary experiment on 27 November 1982. Using a beamswinging technique, plasma velocity was measured at slant ranges of 645–1170 km, enabling velocity vectors to be derived for invariant latitudes 70°–77°. Although operational problems limited the experiment to 80 min, some interesting observations of high-latitude flows were made. Typical afternoon westward flows of about 1 km s⁻¹ were recorded over much of the interval, but important temporal and spatial variations were also seen as a result of the good time and space resolution of the experiment (5 min and 75 km, respectively). In particular, the westward flow was interrupted for about 10 min by a surge of poleward flow, possibly related to dynamic coupling occurring at the dayside magnetopause, such as a flux transfer event.     

《健康美人36.7°》

正内容简介:东方女性中约有1/2的人受到体寒症的困扰,其中80%以上是20~35岁的职业女性。体温34℃、35℃的女性正在OL人群中激增,这种寒性体质正成为东方女性的美丽杀手!寒性体质对人体有很多害处,它不仅是你美丽肌肤的杀手,还是你健康身体的杀手。本书从教你如何判断自己是否寒性体质开始,通过向食物要体温,向运动要体温,向生活细节要体温……来帮助你改善寒性体质。     

外滩270°视野 究竟什么样

上海外滩东方商旅精品酒店如果想念维港的"幻彩咏香江",那么就来外滩。对于我来讲,面对眼前这流光溢彩的镭射灯光汇演,就如同欣赏一个happyending,有着同样的治愈疗效。华灯初上,黄浦江变身为一个声光交织的水面舞台,对岸矗立的地标景观和摩天     

不来梅,北纬50°的童话

<正>不来梅是一座童话之城,除了重温格林兄弟笔下的著名篇章,1200年的历史,也让这座城市的现实生活充满童话色彩,遍布中世纪木屋的古老街道,威悉河畔连成一串的咖啡馆和餐厅,世界遗产与活泼市集共存的广场,讲述着文艺复兴与大航海时代的辉煌,也展示着一座古城历久弥新的独特魅力。"童话之路"的最北端Die Bremer Stadtmusikanten初夏的傍晚,漫步不来梅(Bremen),这座中世纪古城呈现出一派悠然的姿态,弯曲狭长的街道,纵横交错的路口,古老的德式建筑……不来梅位于威悉河     

东经121°08’北纬29°13’到渔镇石浦做个渔民

<正>东海之滨,象山半岛的最南端,将海洋文化保存最原始的古镇——石浦无时不在的大洋气息三月三踏沙滩,海钓节,开渔节,海鲜节海浪声伴着浓郁的海鲜味让人痴迷,石浦的丰富,不知从何说起……伴着海浪声,让我们到这里做个彻头彻尾的渔民     

漠河 北纬53°的时间简史

位于中国最北部的漠河,有着与其他地主不同的时间节奏。“一天无尽的日夜”,冬天漫长的“黑昼”,注定会给漠河人留下不一样的生活印记。     

环湖360°——纳木错环湖路线图

通常意义上的纳木错,已被当雄县纳木错扎西半岛景区所取代。游客们往往从拉萨出发,赴扎西半岛一日或两日游,也就逗留区区几个小时的时间,顶多算是“到此一游”,浅尝辄止而已。     

流淌在17°的柔软光阴

一阵东风吹出来绝世景观 由市区驶到梅城旅游码头,不过短短半个小时,大家有说有笑踏上“扬帆之星”的游轮,江风拂面吹来无限的惬意,抬眼沿途尽是青山绿水构建而成的诗境.“七里扬帆”景点有“小三峡”之称,融江湖之浩瀚、峡谷之幽深、水乡之秀媚于一体,既是一条山水长廊,也是一条极富情韵的诗画长廊,引人人胜.