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1.
Development and validation of a novel-based combination operational air quality forecasting system in Greece 总被引：1，自引：1，他引：0
Stamatis Zoras Vasilios Evagelopoulos Ioannis Pytharoulis Georgios Kallos 《Meteorology and Atmospheric Physics》2010,106(3-4):127-133
In the present work, a model combination is developed in order to provide the public, in north-western Greece, with the next day air quality forecast. Generally, the development and deployment of a real-time numerical air quality prediction system is technically challenging while even more in complex terrain. The Air Pollution Model (TAPM) (http://www.cmar.csiro.au/research/tapm) is a hydrostatic prognostic mesoscale model. It has been calibrated for the area in recent studies and used in air quality assessments. In 2007, TAPM has started operating in a real-time operational mode for the prediction of next day’s weather forecast, particulate matter (PM10 with an aerodynamic diameter <10 μm) daily average concentration and Air Pollution Indexes. The model setup is a link up between TAPM and SKIRON modeling system (http://forecast.uoa.gr). 相似文献
2.
Zodiatis G. Alexandri S. Pavlakis P. Jonsson L. Kallos G. Demetropoulos A. Georgiou G. Theodorou A. Balopoulos E. 《Annales Geophysicae》1997,14(11):1221-1231
A statistical technique for image processing, the maximum cross correlation (MCC) method, was utilized on sequences of NOAA-AVHRR thermal data in order to explore the surface advective current dynamics at the discharge region of the Hellespont in the North Aegean Sea. A 2D numerical flow model was also used in order to simulate the barotropic flow pattern of the surface water layer. The model was forced with diurnal wind fields obtained for the same period as the satellite infrared images. The currents (magnitude and direction) derived from the two methods compare satisfactorily despite the fact that some model simplifications were made. 相似文献
3.
I. Arsenić D. T. Mihailović D. V. Kapor G. Kallos B. Lalić A. Papadopoulos 《Theoretical and Applied Climatology》2000,67(1-2):109-113
Summary The calculation of rocky surface temperature encounters the problem of unrealistic results due to its large changes at the
interface where the energy balance equation is applied. In order to avoid this, we have modified the “force-restore” method
into a self-consistent procedure for simultaneous determination of both surface and the deep ground temperature. The approach
is applicable to any celestial body where external radiation can be represented by an arbitrary periodic function. The method
is tested with Earth based infrared observation on lunar surface temperature and it showed a high level of accuracy and a
rather fast convergence of procedure.
Received June 28, 1999/Revised June 19, 2000 相似文献
4.
Synoptic and mesoscale weather conditions during air pollution episodes in Athens,Greece 总被引：2，自引：0，他引：2
Based on regular climatological and air quality data from the Greater Athens Area (GAA), the air pollution episodes observed in Athens during the period 1983–1990 were analysed and classified. The main characteristics of atmospheric conditions during days with high air pollution concentrations are summarized too. Model simulations show that the worst air pollution episodes in Athens occur during days with a critical balance between synoptic and mesoscale circulations and/or during days with warm advection in the lower troposphere. 相似文献
5.
A new methodology for the extension of the impact of data assimilation on ocean wave prediction 总被引：1，自引：1，他引：0
It is a common fact that the majority of today's wave assimilation platforms have a limited, in time, ability of affecting
the final wave prediction, especially that of long-period forecasting systems. This is mainly due to the fact that after “closing”
the assimilation window, i.e., the time that the available observations are assimilated into the wave model, the latter continues
to run without any external information. Therefore, if a systematic divergence from the observations occurs, only a limited
portion of the forecasting period will be improved. A way of dealing with this drawback is proposed in this study: A combination
of two different statistical tools—Kolmogorov–Zurbenko and Kalman filters—is employed so as to eliminate any systematic error
of (a first run of) the wave model results. Then, the obtained forecasts are used as artificial observations that can be assimilated
to a follow-up model simulation inside the forecasting period. The method was successfully applied to an open sea area (Pacific
Ocean) for significant wave height forecasts using the wave model WAM and six different buoys as observational stations. The
results were encouraging and led to the extension of the assimilation impact to the entire forecasting period as well as to
a significant reduction of the forecast bias. 相似文献
6.
Summary This paper provides a theoretical calibration of Optical Array Probes (OAP) mounted on a given aircraft, in order to take
into account the aerodynamic influence of the entire aircraft on the measurements obtained. The measured parameters are corrected
through the computation of the air flow-field around the entire aircraft carrying the probes, for different flight conditions,
in order to obtain the corresponding undisturbed values. These undisturbed values have been compared to the microphysical
ones computed by an atmospheric model, the Regional Atmospheric Modeling System (RAMS). It was found that the removal of the
disturbances made by the aircraft on the atmospheric conditions is feasible and provides data that compare much better to
the model results. It is suggested that such kind of airborne data corrections may be performed in order to improve the quality
of the observations if the aircraft and probe geometries are known. Further information regarding the best location of the
probes on the considered aircraft is also obtained. 相似文献
7.
The diurnal evolution of the sea breeze hodograph over the Attic Peninsula has been studied using a three-dimensional numerical mesoscale model with fully nonlinear friction parameterization. The model results compare well with observed hodographs at three points in the modelling domain, and show that the balance of pressure gradient and terrain gradient forcing is dominant, and that this balance may result in either clockwise or anticlockwise rotation. 相似文献
8.
One of the main drawbacks in modern sea wave data assimilation models is the limited temporal and spatial improvement obtained
in the final forecasting products. This is mainly due to deviations coming either from the relevant atmospheric input or from
the dynamics of the wave model, resulting to systematic errors of the forecasted fields of numerical wave models, when no
observation is available for assimilation. A potential solution is presented in this work, based on a combination of advanced
statistical techniques, data assimilation systems, and wave models. More precisely, Kalman filtering algorithms are implemented
into the wave model WAM and the results are assimilated by an Optimum Interpolation Scheme, in order to extend the beneficial
influence of the latter in time and space. The case studied concerns a 3-month period in an open sea area near the South-West
coast of the USA (Pacific Ocean). 相似文献
9.
George Galanis Dan Hayes George Zodiatis Peter C. Chu Yu-Heng Kuo George Kallos 《Marine Geophysical Researches》2012,33(1):1-15
In this paper the main wave height characteristics in the Mediterranean Sea are studied from both observational and numerical
perspectives. The numerical wave model WAM is employed on a high spatial resolution mode and in two different versions, one
of which incorporates information for sea surface currents. Altimeter data obtained from all available satellite missions
over the area are also utilized. The data sets are analyzed both by conventional statistical measures as well as by advanced
techniques provided by a relatively new branch of mathematics, information geometry, in the framework of which the data under
study and the distributions that they form are treated as elements of non Euclidean spaces. In this framework, novel ideas
for the estimation of the deviations between the observed and modeled values are proposed. 相似文献
10.
Hindcast of oil-spill pollution during the Lebanon crisis in the Eastern Mediterranean, July-August 2006 总被引：2，自引：0，他引：2
Coppini G De Dominicis M Zodiatis G Lardner R Pinardi N Santoleri R Colella S Bignami F Hayes DR Soloviev D Georgiou G Kallos G 《Marine pollution bulletin》2011,62(1):140-153
MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations.The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results. 相似文献