洛阳市城市环境气象监测预报服务研究

利用洛阳市环境监测资料和气象资料,分析了洛阳市污染物浓度的日变化、季节变化、年际变化规律,并分析了污染物浓度与气象因子的关系。在此基础上,通过回归分析预报方法、污染潜势预报方法、CAPPS模式预报方法对洛阳市3种主要污染物的浓度和级别进行了24 h和48 h预测,并建立了气象局与环保部门共享的气象和污染数据库平台,为双方今后的合作奠定了基础。     

Impedance characteristics of carbon steel under cathodic protection

INTRODUCTIONInpraCticalengineeringapplicati0ns,thecormsionofstalundercathodicprotalioncanbecontr0llediftheproodi0np0tenhalisset2O()t03(X)mVnegativewithaspeCttothenatamlcormsi0np0tenial(MasatSugi,l976,Takehiko,l972).Theprotalnp0tentia1edinpraedcalapplicationisbedonexperienceandtheory.Tooru(l985,l986)foundthattheopbocathodicproodionpotentialcoinddedwiththepotentialwhenpolarhati0nresistancemaxndnd,s0thiscoinedencecanbeedt00btainoptbore-sultforcarbonstalundercathodicpronaion.Inthiswork,the…     

绍兴市城镇用地扩展的遥感监测

随着我国改革开放政策的实施,绍兴市的经济得到飞速发展,城市规模迅速扩大。城市扩展趋势如何,土地的开发利用现状如何是制定今后土地利用规划,进行土地管理、开发的重要依据。为此绍兴市土地局开展了以TM影像为基本信息源的城镇遥感监测工作,本文对此工作进行了分析探讨。     

Chemical ozone loss in the Arctic vortex in the winter 1995–96: HALOE measurements in conjunction with other observations

Severe chemical ozone loss has been detected in the Arctic in the winter and spring of 1995–96 by a variety of methods. Extreme reductions in column ozone due to halogen catalysed chemistry were derived from measurements of the Halogen Occultation Experiment (HALOE) on board the Upper Atmosphere Research Satellite in the Arctic vortex. Here, we discuss further aspects of the HALOE observations in the Arctic over this period. Potential problems, both in the data themselves and in the methodology of the data analysis are considered and the reason for the differences between the Arctic ozone losses deduced from HALOE data version 17 and 18 is analysed. Moreover, it is shown that HALOE measurements in the Arctic in winter and spring 1995–96 compare well with observations by other ground-based and satellite instruments.     

Intercomparison of New Zealand filter ozonometer and Dobson spectrophotometer total ozone measurements

A commercial version of the prototype New Zealand narrowband interference filter instrument has been run at Garmisch-Partenkirchen since autumn 1977. The vicinity of the Dobson stations Hohenpeissenberg and Arosa permitted a check of the filter instrument's utility, reliability and long-term stability in total ozone measurement by (i) station to station-or short-range intercomparisons of daily means and (ii) a several days' direct intercomparison at Arosa in spring 1978.The regression analysis with the Hohenpeissenberg data-covering the five month autumn-winter 1977/78 period with highly variable ozone-shows that the filter instrument's direct-sun modeX _AD total ozone values were systematically too low by a conversion factor of 0.93. The excellent proportionality between the instruments is indicated by the standard deviation of only 1,3%. The (–7.0±1.3%) bias perfectly agrees with the result reported byBasher [1] for a similar, yet direct, intercomparison.During the direct Arosa intercomparison the filter instrument also tracked down short-time variations in a remarkable, though biased, parallelism with the Dobson instruments, and theX _AD daily means fit well into the prognostic relationship derived from the preceding autumn-winter short-range intercomparison.A creeping deterioration of the characteristics of the 305.5 nm double filter then prevented any furtherX _AD total ozone intercomparison. No final decision is possible whether this behaviour after a half year's run is typical or just an unusual exception. The otherwise excellent long-term stability is demonstrated by the comparison of theX _CD daily means with the HohenpeissenbergX _AD data for a 1 1/2 year's period (autumn 1977–spring 1979), resulting in the same bias relationship as for theX _AD total ozone measurements.     

Upper Limit of Iodine Oxide in the Lower Stratosphere

It has been suggested that iodine oxides, IOx, could play a significant role in the ozone destruction in the lower stratosphere. To investigate this suggestion, spectra from nine SAOZ uv-visible spectrometer balloon flights were examined for the IO absorption signature between 405 and 450 nm. IO was not detected, either at mid- or high latitude, in the morning or the evening, in summer or winter. An upper limit of 0.2 parts per trillion by volume (pptv) at 20 km and 0.1 pptv at 15 km at the 95% confidence level (2), was derived from the best measurements at 90° SZA at sunset and sunrise. Since a photochemical model shows that 70% of inorganic iodine should be in the form IO at that time, it is concluded that unless iodine chemistry is different from that assumed at the moment, the role of iodine in stratospheric ozone depletion is small.     

A Study of Ozone Laminae Using Diabatic Trajectories, Contour Advection and Photochemical Trajectory Model Simulations.

In this paper, we show that the rate of ozone loss in both polar and mid-latitudes, derived from ozonesonde and satellite data, has almost the same vertical distribution (although opposite sense) to that of ozone laminae abundance. Ozone laminae appear in the lower stratosphere soon after the polar vortex is established in autumn, increase in number throughout the winter and reach a maximum abundance in late winter or spring. We indicate a possible coupling between mid-winter, sudden stratospheric warmings (when the vortex is weakened or disrupted) and the abundance of ozone laminae using a 23-year record of ozonesonde data from the World Ozone Data Center in Canada combined with monthly-mean January polar temperatures at 30 hPa.Results are presented from an experiment conducted during the winter of 1994/95, in phase II of the Second European Stratospheric And Mid-latitude Experiment (SESAME), in which 93 ozone-enhanced laminae of polar origin observed by ozonesondes at different time and locations are linked by diabatic trajectories, enabling them to be probed twice or more. It is shown that, in general, ozone concentrations inside laminae fall progressively with time, mixing irreversibly with mid-latitude air on time-scales of a few weeks. A particular set of laminae which advected across Europe during mid February 1995 are examined in detail. These laminae were observed almost simultaneously at seven ozonesonde stations, providing information on their spatial scales. The development of these laminae has been modelled using the Contour Advection algorithm of Norton (1994), adding support to the concept that many laminae are extrusions of vortex air. Finally, a photochemical trajectory model is used to show that, if the air in the laminae is chemically activated, it will impact on mid-latitude ozone concentrations. An estimate is made of the potential number of ozone molecules lost each winter via this mechanism.     

2008年冬季北京上空上对流层/下平流层臭氧的异常特征

利用国产GPSO3臭氧探空系统观测的大气臭氧探空资料和NCEP再分析资料,结合对天气形势、大气环流背景、高空位涡变化及对流层顶高度扰动的分析,深入研究了2008年冬季北京地区10~14 km高度范围内持续出现的臭氧次峰值及大气臭氧含量异常现象。结果表明:在2008年我国南方雪灾这一特殊时期,引起臭氧垂直分布持续出现次峰值现象及臭氧含量异常的主要原因是平流层空气强烈下沉运动及其与对流层的交换作用,而引起这种下沉运动及平流层-对流层交换则是由于该阶段特殊的天气背景,乌拉尔阻塞高压长时间维持,贝加尔湖到巴尔喀什湖一带横槽稳定存在,里海以东切断低压长期维持,造成冷空气长时间、稳定地南下影响北京上空臭氧的垂直分布。加之副热带急流的出现,北京正处于其入口区左侧,其上空有强烈的辐合下沉运动,有利于平流层空气向下输送。此次臭氧次峰值及臭氧含量异常的现象很好地说明,在冷空气天气过程的影响下,北京地区上空的平流层空气运动及其与对流层的交换十分活跃。     

Atmospheric Circulation Changes in Response to an Observed Stratospheric Zonal Ozone Anomaly

Abstract

In a sensitivity study, the influence of an observed stratospheric zonal ozone anomaly on the atmospheric circulation was investigated using the Fifth Generation European Centre Hamburg Model (ECHAM5) which is a general circulation model. The model was run from 1960 to 1999 (40 years) with a mean seasonal cycle of zonally symmetric ozone. In order to isolate the induced dynamical influence of the observed zonally asymmetric part of the three-dimensional stratospheric ozone, a second run was performed for the boreal extratropics using prescribed monthly means from the 40-year reanalysis dataset from the European Centre for Medium-range Weather Forecasts (ERA-40). The main findings are the interdecadal westward shift of the polar vortex at about 65°N and a significant increase in the number of stratospheric sudden warmings during the 1980–99 period. Under the action of zonally asymmetric ozone a decrease in the Arctic Oscillation was identified between the mid-1980s and the mid-1990s. The lag correlation between the mean Arctic Oscillation at the surface and the daily stratospheric northern annular mode increased in mid-winter. Furthermore, we examined the influence of the stratospheric zonal ozone anomaly on Rossby wave breaking in the upper troposphere and found a significant westward shift of poleward Rossby wave breaking events over western Europe in the winter. By this we show that the stratospheric zonal ozone anomaly has a strong influence on the tropospheric circulation as a result of enhanced dynamical coupling processes.     

Performance Evaluation of a Self-Developed Ozonesonde and Its Application in an Intensive Observational Campaign

To make a detailed test on the reliability and detection performance of the electrochemical concentra- tion cell （ECC） type ozonesonde which had been devel- oped and preliminarily evaluated by the authors, an inten- sive ozonesonde release experiment was held at two sites in Beijing and Changchun in June 2013. The results showed that the mean background current and its standard deviation were 0.03 （0.04） pA and 0.02 （0.03） pA in Bei- jing （Changchun）. The average response time and its standard deviation were 27.8 s （30.4 s） and 4.0 s （3.7 s） in Beijing （Changchun）. The ozone partial pressure profiles at both sites showed a central peak in the stratosphere and a side peak in the boundary layer. Large variation in ozone partial pressure was observed at the middle levels of the atmosphere （10-17 kin）. A more marked gradient of ozone change was observed in Beijing （3.4 mPa km-1） at the lower atmosphere level, as compared to that in Changchun （0.4 mPa km-l）. The results presented in this paper indicate that this self-developed ozonesonde shows a high level of reliability and good performance. The ozonsonde is expected to play an important role in opera- tional observations of ozone profiles.