Stratospheric ozone variability near the IMF sector boundary

Summary We search for the effects of the interplanetary magnetic field (IMF) sector boundary crossing (SBC) in upper stratospheric ozone. The SBUV data (Nimbus-7) at the 10, 3 and 1 hPa levels are analysed for latitudes 45° N and 55° N for winters of the period December 1979 to December 1982. An effect of the IMF SBC wos only found at the 10 hPa level. These first results concerning the IMF SBC effect in upper stratospheric ozone are rather preliminary.

---

¶rt;m uu nu mau () nam aum n () a mam. SBUV ¶rt;a (u-7) a nm ¶rt;au 10, 3 u 1a aauum ¶rt; um 45° u 55° . . ua nu¶rt;a ¶rt;a 1979 – ¶rt;a 1982. m uu a¶rt; m a 10a. mu n mam n uuu a mam m n¶rt;aumu.

     

The IMF sector structure effects in total ozone in central Europe

Summary The influence of the IMF sector structure on the total ozone content is studied in the European middle latitudes (5 stations,46°–52°N, 1°W–20°E) for the winters of the period 1963–1982. The average effect of the IMF sector boundary crossing (SBC) is very weak. The correction for the seasonal trend is quite crucial. Only detrended results are considered to be reliable. A statistically significant and relatively large effect is found to exist in the total ozone only for geoactive proton sector boundaries, while there is no demonstrable effect for non-proton (common) sector boundaries. The effect of proton boundaries consists in a decrease of the total ozone from higher values before the IMF SBC to lower values after the IMF SBC and it differs from the common types of IMF SBC effects. Our results seem to explain the contradiction between results obtained by other authors.

---

¶rt;m uu m mm nam aum n () a n ¶rt;au a nu ¶rt;u uma (5 mau, 46° – 52° .., 1° .¶rt;. – 20° .¶rt;.) ¶rt; u nu¶rt;a 1963–1982. ¶rt;u m nu mau () a. naa a m¶rt; ma. mam mau m¶rt;a umam ¶rt;mu. mamumuu au u a m a¶rt; n ¶rt;auu a m ¶rt;amu nm mau. a mau ua ma m. m nm mau mum na¶rt;uu n ¶rt;au a u au ¶rt; ¶rt; uu au n . a am, m au mam m nmuu ¶rt; mamau ¶rt;u am.

---

---

Presented at the XIX General Assembly of IUGG, Vancouver 1987.     

Influence of the IMF sector boundaries on cosmic rays and tropospheric vorticity

Summary The effect of the IMF sector boundary crossing (IMF SBC) in the vorticity area index (VAI) — the well-known dip in the VAI after IMF SBC — is found to be independent of the IMF SBC effect in the cosmic ray flux. This finding refutes a recent suggestion by Lundstedt [1] that the IMF SBC effect in VAI is caused by a decrease in cosmic ray flux, but supports the concept of the IMF SBC effects in the ionosphere and atmosphere developed by Latovika [2–4]. Cosmic rays seem to affect the troposphere in another way.

---

¶rt;mu nu mau nam aum n ( ) a u¶rt; na¶rt;u aumu () — um uu n — a¶rt; auu m ma nm uu . mm mam nam ¶rt;a n¶rt;u ¶rt;m¶rt;a [1], m m a nuu nma uu , n¶rt;¶rt;uam nu m u u am, aum amu [2–4]. am m uu u m um a mn ¶rt;u a.

     

Low-latitude total ozone measurements in the Brazilian sector

Regular measurements of the atmospheric ozone in the Brazilian sector were started at Cachoeira Paulista (22.7°S, 45.0°W), and Natal (5.8°S, 35.2°W) in May 1974 and November 1978, respectively. The results of the total ozone measurements carried out at these two stations up to 1981 are presented in this communication and compared with other low-and mid-latitude stations. Although Natal is an equatorial station, it presents a prominent annual variation, and the average total ozone content is high compared to satellite measurements. During 1977–78, abnormally low values of total ozone were observed at Cachoeira Paulista. Some preliminary results about the QBO 9quasi-biennial oscillation) during 1974–81 are also presented.     

扇形边界条件下的龙门山壳幔电性结构特征

沿甘肃碌曲—四川龙门山—重庆合川布设了长周期大地电磁剖面,对龙门山及邻区进行了壳幔电性结构探测,采用更直观合理的扇形边界条件下的反演算法对长周期大地电磁资料进行二维反演.该剖面电性结果揭示了自北西向南东岩石圈深部的若尔盖壳幔高阻块体、松潘壳幔低阻带、龙门山壳幔高阻块体和川中壳幔高阻块体电性结构特征;龙门山逆冲推覆构造带下方的龙门山壳幔高阻体显示为向北西延伸的楔形构造,推断龙门山及松潘—甘孜地块由于受青藏高原东缘和上扬子地块双向挤压,松潘—甘孜地块地壳物质向龙门山逆冲推覆,中下地壳至上地幔向下向南东俯冲,呈现上扬子地块西缘壳幔高阻楔形体插入青藏高原东缘的态势;初步认为上扬子地块西缘深部以松潘壳幔韧性剪切带作为中新生代以来的边界.     

Anomalous solar-diurnal variations in cosmic rays related to crossing of the IMF sector boundaries by the Earth and the problem of earthquakes

Based on a comparison of the cases of a decrease in the ratio of A _n/A _μ (where A _n and A _μ are the amplitudes of the diurnal variations of the neutron and hard cosmic ray components) to the instants of the Earth crossing the neutral IMF, it has been indicated that the process of such crossing is most effective for stimulating large destructive earthquakes with a magnitude of M ≥ 6. The 11-year period in the cyclicity of the occurrence probability of the above earthquakes has been revealed.     

The response of the total electron content to the interplanetary magnetic sector boundary crossing

¶rt;m uu n ¶rt;au m uu nu mau nam aum n. mu uu auam mmmuu uuu ¶rt;u u naam. a¶rt;am auu ¶rt; uuu n ¶rt;au m u u. a auu a¶rt;am nuu amm 245 . ¶rt;aam umnmau m a¶rt;a uu.     

Anisotropy and polymodal distribution of IMF fluctuations

The IMF statistical characteristics, depending on duration of the averaging intervals, are studied based on the ACE spacecraft measurements. The distributions of the induction (B) vector directions and the estimates of the variance and excess coefficient of the vector components are presented. The polymodal model of the density distribution function of the vector (B) component variations is proposed. The parameters of this model, which make it possible to approximate empirical distributions accurate within several hundredths of percent, are presented.     

Vertical distribution of ozone in the planetary boundary layer at the Ming Tombs, Beijing

Surface ozone (O3) and vertical O3 distribution in the planetary boundary layer (PBL) at the Ming Tombs (40°17′15″N, 116°12′51″E), Beijing during September 7―12, 2001 were measured by ground based measurements and an in-situ tethersonde system. The results indicated that O3 concentration measured at surface level agreed well with that measured by tethersonde system in daytime when active thermal mixing was dominated. Ozone showed the lowest concentration before the sunrise and then gradually increased in the morning and reached the maximum in the afternoon 14:00―17:00 (lst). After sunset, O3 gradually decreased and resulted in low value below 200―300 m due to surface loss processes and chemical destruction in stable boundary layer characterized by temperature inversions. High O3 was observed whenever there was pollutants transport from the metropolitan areas of Beijing. Our analysis suggested the complex terrain of the Ming Tombs region caused pollutants transported from Beijing to accumulate in the PBL, and resulted in severe O3 pollution, with a maximum over 160×10-9, when the synoptic conditions was favorable for photochemical O3 production.     

Pc3 pulsations during variable IMF conditions

Pc3 geomagnetic field fluctuations detected at low latitude (L’Aquila, Italy) during the passage of a high velocity solar wind stream, characterized by variable interplanetary magnetic field conditions, are analyzed. Higher frequency resonant fluctuations and lower frequency phenomena are simultaneously observed; the intermittent appearance and the variable frequency of the longer period modes can be well interpreted in terms of the variable IMF elements; moreover their polarization characteristics are consistent with an origin related to external waves propagating in antisunward direction. A comparison with simultaneous observations performed at Terra Nova Bay (Antarctica) provides additional evidence for a clear relationship between the IMF and Pc3 pulsations also at very high latitudes.     

Further ozone transport calculations and the spring maximum in ozone amount

Summary Calculations of the covariance between ozone amounts and meridional wind in the lower stratosphere are presented for all stations in the northern hemisphere for the IGY-IGC. Northward ozone transport occurs by large-scale quasi-horizontal transient and standing eddies and the transport is a maximum early in the year. It is suggested that the transport is governed by the exchange of energy between the troposphere and stratosphere and data are presented on the energy transformations within the lower stratosphere and the transfer of energy into the region which support this suggestion. The vertical flux of energy is also calculated from tropospheric data and its seasonal changes are seen to be in the correct phase to explain the spring maximum in ozone amount.The research reported in this article was sponsored by the Atomic Energy Commission under Contract AT (30-1)2241.     

The IMF structure effects in vernal and autumnal midlatitude ionosphere

au a u naam u a nu¶rt; 1963–1973 . naam, m aum mun ma m mm nam aum n (II) na¶rt;am m u a uu ¶rt; u u,¶rt; ua ma u¶rt;, u u¶rt;a ma mn muna. mu u m ¶rt;u mam nm nmum n¶rt;auma amu m m mm II u a¶rt; ¶rt; n.     

Relationship between the IMF azimuthal angle and solar wind velocity

The relationship between the IMF azimuthal angle and plasma velocity has been studied independently for three types of solar wind streams (recurrent and transient high-speed streams and low-speed background wind) based on the interplanetary medium parameters measured in the near-Earth orbits in 1964–1996. The relationships between the IMF azimuthal angle cotangent and plasma velocity are close to linear but strongly differ from one another and from the theoretical relationship for all types of streams. These differences area caused by the magnetic field disturbance on the time scales smaller than a day, and the effect of this disturbance has been studied quantitatively. The effective periods of rotation of the IMF sources on the Sun, depending on the solar cycle phase, have been obtained from the relations between the IMF azimuthal angle cotangent and plasma velocity. During the most part of the solar cycle, the periods of rotation of the IMF sources are close to the period of rotation of the solar equator but abruptly increase to the values typical of the solar circumpolar zones in the years of solar minimums.     

行星际磁场北向时太阳风－磁层的能量耦合

利用量纲分析法研究太阳风磁层的能量耦合问题。得到了在考虑磁层对太阳风的粘滞作用情况下,行星际磁场北向时的太阳风－磁层能量耦合函数,并首次在耦合函数中引入太阳风温度变量,在此基础上得到了一般情况下的太阳风－磁层耦合函数．     

Polar ionospheric responses to solar wind IMF changes

Auroral and airglow emissions over Eureka (89° CGM) during the 1997/98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and variable. During most of the period, B_z was northward and polar arcs were observed. Several overpasses by DMSP satellites during the four day period provided a clear picture of the particle precipitation producing the polar arcs. The spectral character of these events indicated excitation by electrons of average energy 300 to 500 eV. Only occasionally were electrons of average energy up to 1 keV observed and these appeared transitory from the ground optical data. It is noted that polar arcs appear after sudden changes in IMF B_y, suggesting IMF control over arc initiation. When B_y is positive there is arc motion from dawn to dusk, while B_y is negative the motion is consistently dusk to dawn. F-region (anti-sunward) convections were monitored through the period from 630.0 nm emissions. The convection speed was low (100/150 m/s) when B_z was northward but increased to 500 m/s after B_z turned southward on January 20.     

行星际磁场北向时太阳风－磁层的能量耦合

利用量纲分析法研究太阳风磁层的能量耦合问题。得到了在考虑磁层对太阳风的粘滞作用情况下，行星际磁场北向时的太阳风－磁层能量耦合函数，并首次在耦合函数中引入太阳风温度变量，在此基础上得到了一般情况下的太阳风－磁层耦合函数．     

行星际磁场北向时太阳风－磁层的能量耦合

利用量纲分析法研究太阳风磁层的能量耦合问题。得到了在考虑磁层对太阳风的粘滞作用情况下，行星际磁场北向时的太阳风－磁层能量耦合函数，并首次在耦合函数中引入太阳风温度变量，在此基础上得到了一般情况下的太阳风－磁层耦合函数．     

Aerosol extinction and ozone measurements

The effect of aerosol extinction on Dobson measurements of total ozone is investigated, and several recent attempts to resolve this problem are reviewed. It is pointed out that the balloon measurements of Paetzold and his colleagues circumvent this problem: Solar-cycle and quasi-biennial effects can be clearly discerned in the balloon data. It is suggested that Paetzold's data would be ideal for testing stratospheric models and searching for man's effect on the stratospheric ozone layer.