The Open Atmospheric Science Journal最新文献_第7页

An Adaptive Base Point Algorithm for the Retrieval of Aerosol Microphysical Properties 气溶胶微物理特性检索的自适应基点算法

The Open Atmospheric Science Journal Pub Date : 2011-04-25 DOI: 10.2174/1874282301105010061

L. Osterloh, C. Böckmann, R. Mamouri, A. Papayannis

{"title":"An Adaptive Base Point Algorithm for the Retrieval of Aerosol Microphysical Properties","authors":"L. Osterloh, C. Böckmann, R. Mamouri, A. Papayannis","doi":"10.2174/1874282301105010061","DOIUrl":"https://doi.org/10.2174/1874282301105010061","url":null,"abstract":"We propose a new iterative algorithm for the retrieval of the microphysical properties of stratospheric and tropospheric aerosols from multiwavelength lidar data. We consider the basic equation as an ill-posed problem and solve the system derived from spline collocation via a Pade iteration. The algorithm takes special care of the fact that the reconstruction of the distribution via spline collocation is very sensitive to the choice of base points of the chosen spline basis. The algorithm makes use of this fact by changing the base points used for the spline collocation at certain iteration steps. In addition, the effects of projection to ensure a nonnegative solution are examined. We tested how well this and other algorithms are suitable for retrieving the complex refractive index of the particles as well. We also examine whether the algorithm is capable of distinguishing between different, very small imaginary parts of the refractive index, which is often a main problem in practice. Finally, the algorithm is applied to real multiwavelength Raman lidar data and our results are partially validated by the thermodynamic chemical model Isorropia II.","PeriodicalId":122982,"journal":{"name":"The Open Atmospheric Science Journal","volume":"198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125731462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

On the Features of Magnetogradient Planetary Waves in the Approximation of the Spherical Symmetry of the Ionosphere 磁梯度行星波在电离层球对称近似中的特征

The Open Atmospheric Science Journal Pub Date : 2011-04-01 DOI: 10.2174/1874282301105010033

G. Jandieri, A. Ishimaru, V. Gavrilenko, A. Surmava, A. Gvelesiani

引用次数: 0

Multi-Frequency HF Observations of Farley-Buneman Phase Velocities 法利-布曼相速度的多频高频观测

The Open Atmospheric Science Journal Pub Date : 2011-04-01 DOI: 10.2174/1874282301105010050

D. Moorcroft, L. Kagan, R. S. Kissack

引用次数: 1

Detecting a Large-Scale Upper-Atmospheric Plasma Inhomogeneity Using the Method of Multifrequency Radio Sounding in the Decametric Wavelength Range 利用十米波长范围内的多频无线电探测方法探测大尺度大气上层等离子体不均匀性

The Open Atmospheric Science Journal Pub Date : 2011-04-01 DOI: 10.2174/1874282301105010043

N. T. Afanasiev, A. Afanasiev, V. Markov

引用次数: 0

Editorial: Waves Propagation in the Upper Atmosphere 社论:波在高层大气中的传播

The Open Atmospheric Science Journal Pub Date : 2011-04-01 DOI: 10.2174/1874282301105010032

G. Jandieri

引用次数: 0

Detection of Tornado Frequency Trend Over Ontario, Canada 加拿大安大略省龙卷风频率趋势的探测

The Open Atmospheric Science Journal Pub Date : 2011-03-16 DOI: 10.2174/1874282301105010027

Z. Cao, Huaqing Cai

引用次数: 13

On the Stability of Three-Dimensional Disturbances in Stratified Flow with Lateral and Vertical Shear 横向和垂直剪切分层流中三维扰动的稳定性研究

The Open Atmospheric Science Journal Pub Date : 2011-02-17 DOI: 10.2174/1874282301105010023

I. Panayotova, J. McHugh

引用次数: 0

Long-Term Dependencies of Annual and Semiannual Components of NmF2 Over Concepción NmF2年际和半年分量在Concepción上的长期依赖关系

The Open Atmospheric Science Journal Pub Date : 2011-01-31 DOI: 10.2174/1874282301105010002

M. Bravo, A. Foppiano, R. A. Rio

{"title":"Long-Term Dependencies of Annual and Semiannual Components of NmF2 Over Concepción","authors":"M. Bravo, A. Foppiano, R. A. Rio","doi":"10.2174/1874282301105010002","DOIUrl":"https://doi.org/10.2174/1874282301105010002","url":null,"abstract":"In this work an attempt is made to determine whether the annual and semiannual components of the NmF2 observed over Concepcion (36.8°S; 73.0°W), Chile, exhibit long-term trends. Monthly median hourly values of NmF2 determined from ionosonde observations are analyzed. Although the assessed trends for NmF2 and for the semiannual and annual components of NmF2, are hardly significant by any statistical test, they exhibit a systematic diurnal evolution. NmF2 trends are almost null during night time and negative from around noon to the early evening. The same can be said for trends of the amplitudes of the semiannual component. On the contrary, trends for the annual component are always positive and exhibit a rather irregular diurnal pattern. It seems reasonable then to particularly look for an explanation of the semiannual component long-term changes when concerned with long-term changes of NmF2. The semiannual variation is linked to composition and thermospheric wind effects, and solar zenith angle changes which may be connected to changes of the strength of the global circulation. But, more study is needed to envisage the changes on the semiannual component of NmF2 which may arise from eventual long-term changes of the global circulation.","PeriodicalId":122982,"journal":{"name":"The Open Atmospheric Science Journal","volume":"6 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122701087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Stratospheric Temperature Trends Between 10 and 70 hPa During the Period 1948-2009 1948-2009年间10 - 70 hPa之间的平流层温度趋势

The Open Atmospheric Science Journal Pub Date : 2011-01-31 DOI: 10.2174/1874282301105010016

M. M. Z. Artigas, P. Campra

{"title":"Stratospheric Temperature Trends Between 10 and 70 hPa During the Period 1948-2009","authors":"M. M. Z. Artigas, P. Campra","doi":"10.2174/1874282301105010016","DOIUrl":"https://doi.org/10.2174/1874282301105010016","url":null,"abstract":"Trends in zonal mean temperatures between 10 and 70 hPa have been assessed for the period 1948-2009 using zonal monthly mean temperature from the NCEP/NCAR reanalysis dataset. Monthly temperature linear trends were calculated for the Northern and Southern Hemisphere at a 5o step in latitude. The observed trend pattern agrees with a general cooling for every month. The area of negative trends, in the latitude-month grid, increases as we go down in the stratosphere. Positive trends are also observed, mainly at 10 hPa for equatorial zones and summer northern and southern latitudes, and also at southern high-latitudes during the months July-February for every height analyzed. The positive trends observed at 10 hPa at equatorial and mid-latitudes are due to a warming from the beginning of the record until the beginning of 1980s, coincident with the El Chichon eruption. In the case of high latitudes, also at 10 hPa, there seems to be a \"step\" in 1979. For lower altitudes the positive trends are smoother. In the case of 10 hPa we suggest as a hint, that the temperature behavior for the \"warming\" cases follows the 11-year running mean of the total solar irradiance.","PeriodicalId":122982,"journal":{"name":"The Open Atmospheric Science Journal","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128930005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Possible Sources of Long-Term Variations in the Mid-Latitude Ionosphere 中纬度电离层长期变化的可能来源

The Open Atmospheric Science Journal Pub Date : 2011-01-31 DOI: 10.2174/1874282301105010009

A. Elias

{"title":"Possible Sources of Long-Term Variations in the Mid-Latitude Ionosphere","authors":"A. Elias","doi":"10.2174/1874282301105010009","DOIUrl":"https://doi.org/10.2174/1874282301105010009","url":null,"abstract":"Trends in the upper atmosphere, together with the global warming of the lower atmosphere, are part of the global change of the Earth system. In the present work, which is focused in the upper atmosphere, long-term variations of the critical frequency of the ionospheric F2 layer, foF2, are studied in terms of the following possible causes: (1) long- term variations of the solar EUV radiation shown by the solar cycle length (SCL), (2) long-term variations in geomagnetic activity measured by the aa index, (3) the increasing greenhouse gases concentration in the lower atmosphere which would be producing a temperature decrease in the upper atmosphere, and (4) the Earth's main magnetic field secular variation, which implies changes in the dip angle (I) affecting the thermospheric neutral winds that move the conducting plasma of the ionosphere. For this purpose, foF2 time series of four mid-latitude stations were processed. After filtering the solar activity effect, the long-term variability of these time series and that of the mentioned possible trend sources, were analyzed. The study of trends in the upper atmosphere is an important contribution to one of the present focus of climate science that is the determination of the extent to which human activities are altering the planetary energy balance through the emission of greenhouse gases and pollutants.","PeriodicalId":122982,"journal":{"name":"The Open Atmospheric Science Journal","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117308119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5