Autumn MIST

Last year's one-day autumn meeting of the MIST (Magnetosphere, Ionosphere and Solar–Terrestrial) community was held on 22 November 2002 at the Geological Society, Burlington House. Jim Wild reports.     

Autumn MIST 2009

Colin Forsyth, Nicola Longden, Andrew Walsh and Robert Wicks summarize a MIST meeting where ground-based ionospheric science came under the spotlight, amid the broader concerns of the MIST community.     

Granta MIST

The magnetosphere, ionosphere and solar–terrestrial physics community gathered at Selwyn College, University of Cambridge, for three days between Tuesday 5 April and Thursday 7 April 2005. Neil Arnold and Andrew Lyons report.     

Soarly MIST

The magnetosphere, ionosphere and solar–terrestrial physics community gathered near the village of Soarly, at Stanford Hall, University of Leicester for its spring meeting, bathed for the most part in unseasonally warm and sunny weather. Neil Arnold reports.     

Interplanetary MIST

The London MIST meeting in November covered current research using satellites to investigate planetary environments across the solar system, including our own. Earth-bound instruments, GPS and modelling also came under discussion, as did a series of results from the Cluster mission. Neil Arnold reports.     

Millennium MIST

The magnetosphere, ionosphere and solar–terrestrial physics community gathered at the Civil Engineering Department, Imperial College of Science Technology and Medicine, London from 11–13 April 2000. Neil Arnold and Peter Cargill report.     

Season of MIST

Neil Arnold reports from the Autumn MIST Meeting held on 24 November 2000 at Burlington House, where discussion included a new electronic initiative that could improve access to solar–terrestrial data across the country.     

London MIST 2004

The annual one-day meeting of the MIST (Magnetosphere, Ionosphere and Solar–Terrestrial) community was held in November 2004 at Burlington House, with contributions on data and ideas ranging from Cassini to Cluster, with stops at many experiments in between.     

Auld Reekie MIST

The magnetosphere, ionosphere and solar–terrestrial physics community gathered at the University of Edinburgh from 29 March – 1 April 2004, for a meeting including a day of joint sessions with UKSP. The four day programme reflected the breadth and depth of the science covered. Neil Arnold and Alan Thomson report; the UKSP meeting is covered in the following pages.     

Jorvik MIST – 2001

The magnetosphere, ionosphere and solar–terrestrial physics community gathered at the Department of Chemistry, University of York from 9–11 April 2001. Neil Arnold and Ian Mann report.     

Steel MIST and UKSP together at Sheffield

The annual UK Solar Physics meeting this year joined a MIST meeting for the first time. The two drew together the considerable UK solar and solar–terrestrial physics community for discussion and debate at the University of Sheffield from 9–12 April 2002. Neil Arnold and Graham Bailey (MIST) and Robert Erdélyi (UKSP) report on this innovative joint meeting.     

Autumn intensification of the Ryukyu Current during 2003-2007

Inverse calculations using data from 16 repeat hydrographic transects collected from April 2003 to June 2007 have yielded velocity structures and volume transports(VTs) of the Ryukyu Current in the region east of the northern Ryukyu Islands.The inverse calculation results show that the Ryukyu Current is dominated by a subsurface velocity core with maximum velocities from 15.1 to 80.0 cm/s,whose positions vary between 110 and 600 dbar and 27.2°-28.2°N along the transect.The mean velocity exhibits a subsurface velocity core with a maximum value of 24.6 cm/s at 326 dbar depth,a VT of 14.0 Sv(1 Sv≡106 m3/s),a vertical dimension of 800 m,and a horizontal dimension of 60 km.The seasonal mean velocities show that the Ryukyu Current is stronger in autumn than in other seasons.It is suggested that this seasonal variation is coincident with the intensification of the anticyclonic eddy south of Shikoku,Japan.     

冬季富营养化湖泊中水生植物的恢复及净化作用

秋末冬初大多数水生植物处于衰亡期,在透明度较低的富营养化湖泊中引种和恢复水生植物往往十分困难,借助物理生态工程技术,秋末冬初在重富营养化湖泊中新建的1000m^2围隔内,引种漂移植物和沉水植物;利用群落间的相互作用及人工干预,若干种水生高等植物不仅能够引种存活,而且能够快速提高水体透明度、改善水质,引种水生高等植物3周后,有水生高等植物的围区内水体透明度提高一倍,并长期保持在较高水平,6周后,有植物围区内水体TN浓度比对照围区及开敞水域分别降低43．7％和59．4％,TP分别降低50．3％和57．0％;6个月后,TN分别降低61．6％和79．7％有植物围区较开敞水体降低72．9％。     

2009年秋至2010年春我国西南地区干旱及与历史场次干旱对比分析

2009年10月至2010年4月,我国西南地区由于受厄尔尼诺影响,气温偏高、降雨偏少,发生了秋冬春三季连旱,耕地受旱面积占全国同期耕地受旱面积的78%,受灾人口和大牲畜饮水困难头数都达到了近十年来该地区的最高水平。通过对比本次和历史场次干旱发现,西南干旱并非稀遇现象,1951~1990年的40年间该地区曾发生干旱12次,且1949年以来,干旱有缓慢加重的趋势;本次旱灾与1963年旱灾在时空分布、灾害成因和灾情方面较为相似,但从气象干旱的角度来看,虽然1963年部分受旱地区无有效降雨历时为11个月,高于本次旱灾的6个月,但本次受灾率和成灾率均为1949年以来的最大值,说明在快速发展背景下,经济社会面对干旱显得更为脆弱。这些结论对于认清西南地区干旱特性与旱灾演变规律,加强抗旱减灾体系建设,具有重要的参考价值。     

春秋两季鄱阳湖浮游动物的编目、数量分布与变动

分析鉴定了1999年春、秋两季,在鄱阳湖区8个断面24个采样站采得的水样．共观察到各类浮游动物共150种．其中轮虫动物物种最为丰富,为96种,占总种数的64．0％,且单位体积的数量亦呈明显优势,说明轮虫动物是该湖区浮游动物的优势类群;其次为原生动物．24个采样站中,原生动物、轮虫动物、枝角类、桡足类这四类浮游动物个体数量分布的差异极大,其中第10、12、13和23号站中的个体数量较高,超过100ind／L最大数量出现在13号站,个体数量高达1101．60ind／L鄱阳湖浮游动物的数量有明显的季节变动,尤属轮虫的变动最大．本次调查中轮虫和枝角类的数量春季大于秋季,而原生动物和桡足类则秋季大于春季．     

Zooplankton biomass and production in the North Sea during the Autumn Circulation experiment, October 1987–March 1988

Distribution and abundance of zooplankton in the North Sea during the Autumn Circulation Experiment (October 1987–March 1988) were examined. From shipboard egg production incubations and the distributions of eggs, nauplii and females, the productivity of various copepod species was described. Against the background of surface temperature, salinity and chlorophyll-a distributions, major seasonal changes in plankton biomass distributions and specific production of copepods were seen. High biomass levels in October rapidly declined into November and January, especially in the north. These changes were followed by early (January/February) production and biomass increases in the southeastern North Sea. Although lowest between November and January, depending on species and location, production continued for many copepod species throughout the winter, despite low temperatures and large predator populations. It was concluded that winter survival of herring larvae and other predators was enhanced by herbivore production in the southeastern North Sea, and that in the north, low herbivore production, competition and predation decreased the probabilities of predator survival. Copepod overwintering strategies and the implications of winter herbivore production and predator abundance for later plankton production processes are discussed.     

安徽霍山戴家院西周-春秋晚期文化层物质变形的显微分析及其意义

皖西霍山戴家院西周-春秋晚期遗址发掘调查中,发现了与构造运动有关的地裂缝,其中充填有粉细砂,初定为地震液化遗迹.从变形物质的定向微观分析中发现了大量显微级地震遗迹标志,如负荷构造,流动构造,截断面,有机质悬浮,等等.这些发现和认识从微观角度验证了遗址所在地区西周-春秋晚期曾发生两次地震事件.上述工作在一定程度上丰富和发展了对我国东部地区史前地震事件的识别和研究方法.     

Significance and Microscopic Analysis of Deformation in the Cultural Remains of Western Zhou Dynasty-Late Spring and Autumn Period at Daijiayuan Ruins in Huoshan,Anhui Province,China

During an excavation survey to the Daijiayuan vestige of the Western Zhou Dynasty-Late Spring and Autumn Period at Huoshan in Western Anhui,a ground crack related to tectonic movement and filled with silty fine sand was found. This phenomenon was initially confirmed to be due to seismic liquefaction. Many microscopic seismic relics,such as load structure,flow structure,cutoff plane and flotation of organic matter were found in the directional microscopic analysis of deformation. These discoveries and cognitions prove that there were two earthquake events taking place in the Western Zhou Dynasty-Late Spring and Autumn Period in this area. Above-mentioned works enrich and develop the research methods to identify prehistoric earthquake event in eastern China area to a certain extent.