Biosensors for marine pollution research,monitoring and control

Measurement of ecological, climatic and anthropogenic changes underpins the formulation of effective management strategies for sustainable use and protection of the marine environment. Sensors are traditionally used in marine studies to determine physical parameters, but there is increasing demand for real-time information about chemical and biological parameters. These parameters are currently measured in samples collected at sea and subsequently analysed in the laboratory. Biosensors fuse the exquisite sensitivity and specificity of living systems with the processing power of microelectronics to deliver simple, inexpensive measurement systems for use in the field or deployment in situ. While their potential for use in the marine environment is enormous, much published work to date has focussed on applications in freshwater and wastewater. Marine applications pose a substantial challenge in the robustness required for remote application, but recent developments in portable medical devices and receptor design suggest that these demands can now be realistically tackled.     

GMS多通道资料综合判别可降水云

利用１９９５年７～１０月影响山东的１２次降水天气过程３７０个时次的ＧＭＳ－５卫星云图,以及对应时次全省９５个雨量观测站自记降水资料,统计分析了静止气象卫星各通道资料与降水概率的关系。探讨了静止气象卫星云图综合识别可降水云的方法。     

不同气候生态棉区化学调控适宜期的试验及其应用

在山东省气候条件下,棉花生长发育主要受热量条件制约．由积温推算出在不同气候生态棉区以及不同品种、种植方式、密度和产量水平下的棉田物候期,由此得到相应棉田各次化调期,可改变田间小气候,提高成铃率１０％～１５％,单铃重增加０．３～０．９ｇ,使棉田因蕾期缩短而改变播期及种植品种,扩大麦棉两熟种植区域,提高棉花品质．     

遥感化探信息综合分析在地质找矿中的应用研究

利用适当比例尺的遥感资料对新疆三区林场金化探异常进行了综合解译分析和评价,并圈定了多处金矿(化)体,在遥感与化探相结合进行地质找矿方面取得了明显效果。     

Solar activity effects in the ionospheric D region

Variations in the D-region electron concentration within the solar activity cycle are considered. It is demonstrated that conclusions of various authors, who have analyzed various sets of experimental data on [e], differ significantly. The most reliable seem to be the conclusions based on analysis of the [e] measurements carried out by the Faraday rotation method and on the theoretical concepts on the D-region photochemistry. Possible QBO effects in the relation of [e] to solar activity are considered and an assumption is made that such effects may be the reason for the aforementioned disagreement in conclusions on the [e] relation to solar indices.Paper Presented at the Second IAGA/ICMA (IAMAS) Workshop on Solar Activity Forcing of the Middle Atmosphere, Prague, August 1997     

On the application of the classic Kessler and Berry schemes in Large Eddy Simulation models with a particular emphasis on cloud autoconversion, the onset time of precipitation and droplet evaporation

Many Large Eddy Simulation (LES) models use the classic Kessler parameterisation either as it is or in a modified form to model the process of cloud water autoconversion into precipitation. The Kessler scheme, being linear, is particularly useful and is computationally straightforward to implement. However, a major limitation with this scheme lies in its inability to predict different autoconversion rates for maritime and continental clouds. In contrast, the Berry formulation overcomes this difficulty, although it is cubic. Due to their different forms, it is difficult to match the two solutions to each other. In this paper we single out the processes of cloud conversion and accretion operating in a deep model cloud and neglect the advection terms for simplicity. This facilitates exact analytical integration and we are able to derive new expressions for the time of onset of precipitation using both the Kessler and Berry formulations. We then discuss the conditions when the two schemes are equivalent. Finally, we also critically examine the process of droplet evaporation within the framework of the classic Kessler scheme. We improve the existing parameterisation with an accurate estimation of the diffusional mass transport of water vapour. We then demonstrate the overall robustness of our calculations by comparing our results with the experimental observations of Beard and Pruppacher, and find excellent agreement.     

The morphology of oxygen greenline dayglow emission

In this study, the morphology of the oxygen greenline dayglow emission is presented. The volume emission rate profiles are obtained by using Solomons glow model. The glow model is updated in terms of recent cross sections, reaction rate coefficients and quantum yield of greenline emission. Throughout most of the thermosphere the modelled and observed emission rates are in reasonably good agreement. In the region between 98 and 120 km, the modelled emission rates are substantially higher (about a factor of 1.7) than the observed emission rates. This discrepancy is discussed in terms of scaling of solar fluxes which accounts the variation of solar activity for the day on which calculations are made. The modelled morphology of greenline emission is compared with those cases where WINDII data is available. The modelled and observed morphology is in reasonably good agreement at most of the latitudes above 120 km. In the mesosphere the qualitative nature of morphology is very similar to those of WINDII observation except the modelled emission rates are about a factor of 1.7 higher than the observed emission rates.     

Development of a chemistry module for GCMs: first results of a multiannual integration

The comprehensive chemistry module CHEM has been developed for application in general circulation models (GCMs) describing tropospheric and stratospheric chemistry, including photochemical reactions and heterogeneous reactions on sulphate aerosols and polar stratospheric clouds. It has been coupled to the spectral atmospheric GCM ECHAM3. The model configuration used in the current study has been run in an –off-line mode, i.e. the calculated chemical species do not affect the radiative forcing of the dynamic fields. First results of a 15-year model integration indicate that the model ECHAM3/CHEM runs are numerically efficient and stable, i.e. that no model drift can be detected in dynamic and chemical parameters. The model reproduces the main features regarding ozone, in particular intra- and interannual variability. The ozone columns are somewhat higher than observed (approximately 10%), while the amplitude of the annual cycle is in agreement with observations. A comparison with HALOE data reveals, however, a serious model deficiency regarding lower-stratosphere dynamics at high latitudes. Contrary to what is concluded by observations, the lower stratosphere is characterized by slight upward motions in the polar regions, so that some of the mentioned good agreements must be considered as fortuitous. Nevertheless, ECHAM3/CHEM well describes the chemical processes leading to ozone reduction. It has been shown that the mean fraction of the northern hemisphere, which is covered by polar stratospheric clouds (PSCs) as well as the temporal appearance of PSCs in the model, is in fair agreement with observations. The model results show an activation of chlorine inside the polar vortex which is stronger in the southern than in the northern winter hemisphere, yielding an ozone hole over the Antarctic; this hole, however, is also caused to a substantial degree by the dynamics. Interhemispheric differences concerning reformation of chlorine reservoir species HCl and ClONO₂ in spring have also been well reproduced by the model.     

Extrapolating EISCAT Pedersen conductances to other parts of the sky using ground-based TV auroral images

Ionospheric conductivity is not very easily measured directly. Incoherent scatter radars perhaps offer the best method but can only measure at one point in the sky at any one time and are limited in their time resolution. Statistical models of average conductivity are available but these may not be applied to individual case studies such as substorms. There are many instances where a real-time estimate of ionospheric conductivity over a large field-of-view is highly desirable at a high temporal and spatial resolution. We show that it is possible to make a reasonable estimate of the noctural height-integrated Pedersen conductivity, or conductance, with a single all-sky TV camera operating at 557.7 nm. This is not so in the case of the Hall conductance where at least two auroral wavelengths should be imaged in order to estimate additionally the energy of the precipitating particles.     

Effects of geomagnetic activity on the mesospheric electric fields

The results of three series of rocket measurements of mesospheric electric fields carried out under different geomagnetic conditions at polar and high middle latitudes are analysed. The measurements show a clear dependence of the vertical electric fields on geomagnetic activity at polar and high middle latitudes. The vertical electric fields in the lower mesosphere increase with the increase of geomagnetic indexes K_p and K_p. The simultaneous increase of the vertical electric field strength and ion conductivity was observed in the mesosphere during geomagnetic disturbances. This striking phenomenon was displayed most clearly during the solar proton events of October, 1989 accompanied by very strong geomagnetic storm (K_p = 8+). A possible mechanism of generation of the vertical electric fields in the mesosphere caused by gravitational sedimentation of charged aerosol particles is discussed. Simultaneous existence in the mesosphere of both the negative and positive multiply charged aerosol particles of different sizes is assumed for explanation of the observed V/m vertical electric fields and their behaviour under geomagnetically disturbed conditions.Paper Presented at the Second IAGA/ICMA (IAMAS) Workshop on Solar Activity Forcing of the Middle Atmosphere, Prague, August 1997