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Spatial and Temporal Variation in PBL Height over the Korean Peninsula in the KMA Operational Regional Model  [PDF]
Seung-Jae Lee,Juwon Lee,Steven J. Greybush,Minseok Kang,Joon Kim
Advances in Meteorology , 2013, DOI: 10.1155/2013/381630
Abstract: Spatial and temporal variations in planetary boundary layer height (PBLH) over the Korean Peninsula and its surrounding oceans are investigated using a regional grid model operated at the Korea Meteorological Administration (KMA). Special attention is placed on daily maximum mixing height for evaluation against two radiosonde observation datasets. In order to construct a new high-resolution PBLH database with 3-hour time and 10?km spatial resolution, short-term integrations with the regional model are carried out for a one-year period from June 2010 to May 2011. The resulting dataset is then utilized to explore the seasonal patterns of horizontal PBLH distribution over the peninsula for one year. Frequency distributions as well as monthly and diurnal variations of PBLH at two selected locations are examined. This study reveals specific spatiotemporal structure of boundary layer depth over the Korean Peninsula for the first time at a relatively high-resolution scale. The results are expected to provide insights into the direction for operational tuning and future development in the model boundary layer schemes at KMA. 1. Introduction The diurnally evolving structure of the planetary boundary layer (PBL) for a typical synoptic high-pressure system is described by Stull [1]. The depth of the PBL provides important information for numerical weather prediction (NWP) and atmospheric dispersion models. It has been used as a key parameter in the trigger function for convection in cumulus parameterization schemes in many NWP models (e.g., [2, 3]). Accurate prediction of PBL’s vertical extent is crucial in determining whether harmful gases (e.g., those erupted from a volcano) would reach the ground or not [4]. It affects near-surface atmospheric pollutant concentrations (e.g., [5]), low-level moisture availability, and updraft conditions prior to thundershowers (e.g., [6]). In particular, daytime mixed-layer (ML) height has been regarded as the location of a capping temperature inversion atop the convective boundary layer. Raupach et al. [7] and Denmead et al. [8] formularized the relationship between carbon dioxide concentration and ML depth through entrainment processes. To identify the ML top, there have been several methods for which radiosondes, wind profilers, and ceilometer/light detection and ranging (LIDAR) were utilized (e.g., [9–14]). These kinds of techniques to extract PBLH information have been also applied over the Korean Peninsula to surface flux [15–17], radiosonde [18, 19], LIDAR [20], and wind profiler [21] data. Most of the researchers
An operational procedure for Hankel type integrals
C. Nasim
International Journal of Mathematics and Mathematical Sciences , 1987, DOI: 10.1155/s0161171287000346
Abstract: In this paper, an operational procedure is established to evaluate Hankel type integrals. First, an operator L( ), ¢ ‰ ¢ ’xddx is constructed, which defines the integral. Then making use of some basic properties of this operator, an elementary procedure is developed for evaluating integrals for a special class of analytic functions. A few example are given to illustrate the technique.
Application of Direct Assimilation of ATOVS Microwave Radiances to Typhoon Track Prediction
ZHANG Hu,XUE Jishan,ZHU Guofu,ZHUANG Shiyu,WU Xuebao,ZHANG Fengying,
ZHANG Hu
,XUE Jishan,ZHU Guofu,ZHUANG Shiyu,WU Xuebao,ZHANG Fengying

大气科学进展 , 2004,
Abstract: In order to solve the difficult problem of typhoon track prediction due to the sparsity of conventional data over the tropical ocean, in this paper, the No. 0205 typhoon Rammasun of 4-6 July 2002 is studied and an experiment of the typhoon track prediction is made with the direct use of the Advanced TIROS-N Operational Vertical Sounder (ATOVS) microwave radiance data in three-dimensional variational data assimilation. The prediction result shows that the experiment with the ATOVS microwave radiance data can not only successfully predict the observed fact that typhoon Rammasun moves northward and turns right, but can also simulate the action of the fast movement of the typhoon, which cannot be simulated with only conventional radiosonde data. The skill of the typhoon track prediction with the ATOVS microwave radiance data is much better than that without the ATOVS data. The typhoon track prediction of the former scheme is consistent in time and in location with the observation. The direct assimilation of ATOVS microwave radiance data is an available way to solve the problem of the sparse observation data over the tropical ocean, and has great potential in being applied to typhoon track prediction.
A practical guide for operational validation of discrete simulation models
Leal, Fabiano;Costa, Rafael Florêncio da Silva;Montevechi, José Arnaldo Barra;Almeida, Dagoberto Alves de;Marins, Fernando Augusto Silva;
Pesquisa Operacional , 2011, DOI: 10.1590/S0101-74382011000100005
Abstract: as the number of simulation experiments increases, the necessity for validation and verification of these models demands special attention on the part of the simulation practitioners. by analyzing the current scientific literature, it is observed that the operational validation description presented in many papers does not agree on the importance designated to this process and about its applied techniques, subjective or objective. with the expectation of orienting professionals, researchers and students in simulation, this article aims to elaborate a practical guide through the compilation of statistical techniques in the operational validation of discrete simulation models. finally, the guide's applicability was evaluated by using two study objects, which represent two manufacturing cells, one from the automobile industry and the other from a brazilian tech company. for each application, the guide identified distinct steps, due to the different aspects that characterize the analyzed distributions
Geophysical validation of MIPAS-ENVISAT operational ozone data  [PDF]
U. Cortesi,J. C. Lambert,C. De Clercq,G. Bianchini
Atmospheric Chemistry and Physics Discussions , 2007,
Abstract: The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), on-board the European ENVIronmental SATellite (ENVISAT) launched on 1 March 2002, is a middle infrared Fourier Transform spectrometer measuring the atmospheric emission spectrum in limb sounding geometry. The instrument is capable to retrieve the vertical distribution of temperature and trace gases, aiming at the study of climate and atmospheric chemistry and dynamics, and at applications to data assimilation and weather forecasting. MIPAS operated in its standard observation mode for approximately two years, from July 2002 to March 2004, with scans performed at nominal spectral resolution of 0.025 cm 1 and covering the altitude range from the mesosphere to the upper troposphere with relatively high vertical resolution (about 3 km in the stratosphere). Only reduced spectral resolution measurements have been performed subsequently. MIPAS data were re-processed by ESA using updated versions of the Instrument Processing Facility (IPF v4.61 and v4.62) and provided a complete set of level-2 operational products (geo-located vertical profiles of temperature and volume mixing ratio of H2O,O3, HNO3, CH4, N2O and NO2) with quasi continuous and global coverage in the period of MIPAS full spectral resolution mission. In this paper, we report a detailed description of the validation of MIPAS-ENVISAT operational ozone data, that was based on the comparison between MIPAS v4.61 (and, to a lesser extent, v4.62) O3 VMR profiles and a comprehensive set of correlative data, including observations from ozone sondes,ground-based lidar, FTIR and microwave radiometers, remote-sensing and in situ instruments on-board stratospheric aircraft and balloons, concurrent satellite sensors and ozone fields assimilated by the European Center for Medium-range Weather Forecasting. A coordinated effort was carried out, using common criteria for the selection of individual validation data sets, and similar methods for the comparisons. This enabled merging the individual results from a variety of independent reference measurements of proven quality (i.e., well characterised error budget) into an overall evaluation of MIPAS O3 data quality, having both statistical strength and the widest spatial and temporal coverage. Collocated measurements from ozone sondes and ground-based lidar and microwave radiometers of the Network for Detection Atmospheric Composition Change (NDACC) were selected to carry out comparisons with time series of MIPAS O3 partial columns and to identify groups of stations and time periods with a uniform
Geophysical validation of MIPAS-ENVISAT operational ozone data
U. Cortesi, J. C. Lambert, C. De Clercq, G. Bianchini, T. Blumenstock, A. Bracher, E. Castelli, V. Catoire, K. V. Chance, M. De Mazière, P. Demoulin, S. Godin-Beekmann, N. Jones, K. Jucks, C. Keim, T. Kerzenmacher, H. Kuellmann, J. Kuttippurath, M. Iarlori, G. Y. Liu, Y. Liu, I. S. McDermid, Y. J. Meijer, F. Mencaraglia, S. Mikuteit, H. Oelhaf, C. Piccolo, M. Pirre, P. Raspollini, F. Ravegnani, W. J. Reburn, G. Redaelli, J. J. Remedios, H. Sembhi, D. Smale, T. Steck, A. Taddei, C. Varotsos, C. Vigouroux, A. Waterfall, G. Wetzel,S. Wood
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2007,
Abstract: The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), on-board the European ENVIronmental SATellite (ENVISAT) launched on 1 March 2002, is a middle infrared Fourier Transform spectrometer measuring the atmospheric emission spectrum in limb sounding geometry. The instrument is capable to retrieve the vertical distribution of temperature and trace gases, aiming at the study of climate and atmospheric chemistry and dynamics, and at applications to data assimilation and weather forecasting. MIPAS operated in its standard observation mode for approximately two years, from July 2002 to March 2004, with scans performed at nominal spectral resolution of 0.025 cm 1 and covering the altitude range from the mesosphere to the upper troposphere with relatively high vertical resolution (about 3 km in the stratosphere). Only reduced spectral resolution measurements have been performed subsequently. MIPAS data were re-processed by ESA using updated versions of the Instrument Processing Facility (IPF v4.61 and v4.62) and provided a complete set of level-2 operational products (geo-located vertical profiles of temperature and volume mixing ratio of H2O, O3, HNO3, CH4, N2O and NO2) with quasi continuous and global coverage in the period of MIPAS full spectral resolution mission. In this paper, we report a detailed description of the validation of MIPAS-ENVISAT operational ozone data, that was based on the comparison between MIPAS v4.61 (and, to a lesser extent, v4.62) O3 VMR profiles and a comprehensive set of correlative data, including observations from ozone sondes, ground-based lidar, FTIR and microwave radiometers, remote-sensing and in situ instruments on-board stratospheric aircraft and balloons, concurrent satellite sensors and ozone fields assimilated by the European Center for Medium-range Weather Forecasting. A coordinated effort was carried out, using common criteria for the selection of individual validation data sets, and similar methods for the comparisons. This enabled merging the individual results from a variety of independent reference measurements of proven quality (i.e. well characterized error budget) into an overall evaluation of MIPAS O3 data quality, having both statistical strength and the widest spatial and temporal coverage. Collocated measurements from ozone sondes and ground-based lidar and microwave radiometers of the Network for the Detection Atmospheric Composition Change (NDACC) were selected to carry out comparisons with time series of MIPAS O3 partial columns and to identify groups of stations and time periods with a uniform pattern of ozone differences, that were subsequently used for a vertically resolved statistical analysis. The results of the comparison are classified according to synoptic and regional systems and to altitude intervals, showing a generally good agreement within the comparison error bars in the upper and middle stratosphere. Significant differences emerge in the lower stratosphere and are onl
Validation of MIPAS-ENVISAT NO2 operational data
G. Wetzel, A. Bracher, B. Funke, F. Goutail, F. Hendrick, J.-C. Lambert, S. Mikuteit, C. Piccolo, M. Pirre, A. Bazureau, C. Belotti, T. Blumenstock, M. De Mazière, H. Fischer, N. Huret, D. Ionov, M. López-Puertas, G. Maucher, H. Oelhaf, J.-P. Pommereau, R. Ruhnke, M. Sinnhuber, G. Stiller, M. Van Roozendael,G. Zhang
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2007,
Abstract: The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument was launched aboard the environmental satellite ENVISAT into its sun-synchronous orbit on 1 March 2002. The short-lived species NO2 is one of the key target products of MIPAS that are operationally retrieved from limb emission spectra measured in the stratosphere and mesosphere. Within the MIPAS validation activities, a large number of independent observations from balloons, satellites and ground-based stations have been compared to European Space Agency (ESA) version 4.61 operational NO2 data comprising the time period from July 2002 until March 2004 where MIPAS measured with full spectral resolution. Comparisons between MIPAS and balloon-borne observations carried out in 2002 and 2003 in the Arctic, at mid-latitudes, and in the tropics show a very good agreement below 40 km altitude with a mean deviation of roughly 3%, virtually without any significant bias. The comparison to ACE satellite observations exhibits only a small negative bias of MIPAS which appears not to be significant. The independent satellite instruments HALOE, SAGE II, and POAM III confirm in common for the spring-summer time period a negative bias of MIPAS in the Arctic and a positive bias in the Antarctic middle and upper stratosphere exceeding frequently the combined systematic error limits. In contrast to the ESA operational processor, the IMK/IAA retrieval code allows accurate inference of NO2 volume mixing ratios under consideration of all important non-LTE processes. Large differences between both retrieval results appear especially at higher altitudes, above about 50 to 55 km. These differences might be explained at least partly by non-LTE under polar winter conditions but not at mid-latitudes. Below this altitude region mean differences between both processors remain within 5% (during night) and up to 10% (during day) under undisturbed (September 2002) conditions and up to 40% under perturbed polar night conditions (February and March 2004). The intercomparison of ground-based NDACC observations shows no significant bias between the FTIR measurements in Kiruna (68° N) and MIPAS in summer 2003 but larger deviations in autumn and winter. The mean deviation over the whole comparison period remains within 10%. A mean negative bias of 15% for MIPAS daytime and 8% for nighttime observations has been determined for UV-vis comparisons over Harestua (60° N). Results of a pole-to-pole comparison of ground-based DOAS/UV-visible sunrise and MIPAS mid-morning column data has shown that the mean agreement in 2003 falls within the accuracy limit of the comparison method. Altogether, it can be indicated that MIPAS NO2 profiles yield valuable information on the vertical distribution of NO2 in the lower and middle stratosphere (below about 45 km) during day and night with an overall accuracy of about 10–20% and a precision of typically 5–15% such that the data are useful for scientific studies. In cases whe
Validation of MIPAS-ENVISAT NO2 operational data  [PDF]
G. Wetzel,A. Bracher,B. Funke,F. Goutail
Atmospheric Chemistry and Physics Discussions , 2007,
Abstract: The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument was launched aboard the environmental satellite ENVISAT into its sun-synchronous orbit on 1 March 2002. The short-lived species NO2 is one of the key target products of MIPAS that are operationally retrieved from limb emission spectra measured in the stratosphere and mesosphere. Within the MIPAS validation activities, a large number of independent observations from balloons, satellites and ground-based stations have been compared to European Space Agency (ESA) version 4.61 operational NO2 data comprising the time period from July 2002 until March 2004 where MIPAS measured with full spectral resolution. Comparisons between MIPAS and balloon-borne observations carried out in 2002 and 2003 in the Arctic, at mid-latitudes, and in the tropics show a very good agreement below 40 km altitude with a mean deviation of roughly 3%, virtually without any significant bias. The comparison to ACE satellite observations exhibits only a small negative bias of MIPAS which appears not to be significant. The independent satellite instruments HALOE, SAGE II, and POAM III confirm in common for the spring-summer time period a negative bias of MIPAS in the Arctic and a positive bias in the Antarctic middle and upper stratosphere exceeding frequently the combined systematic error limits. In contrast to the ESA operational processor, the IMK/IAA retrieval code allows accurate inference of NO2 volume mixing ratios under consideration of all important non-LTE processes. Large differences between both retrieval results appear especially at higher altitudes, above about 50 to 55 km. These differences might be explained at least partly by non-LTE under polar winter conditions but not at mid-latitudes. Below this altitude region mean differences between both processors remain within 5% (during night) and up to 10% (during day) under undisturbed (September 2002) conditions and up to 40% under perturbed polar night conditions (February and March 2004). The intercomparison of ground-based NDACC observations shows no significant bias between the FTIR measurements in Kiruna (68° N) and MIPAS in summer 2003 but larger deviations in autumn and winter. The mean deviation over the whole comparison period remains within 10%. A mean negative bias of 15% for MIPAS daytime and 8% for nighttime observations has been determined for UV-vis comparisons over Harestua (60° N). Results of a pole-to-pole comparison of ground-based DOAS/UV-visible sunrise and MIPAS mid-morning column data has shown that the mean agreement in 2
Application of ATOVS Radiance-Bias Correction to Typhoon Track Prediction with Ensemble Kalman Filter Data Assimilation

CUI Limei,SUN Jianhu,QI Linlin,LEI Ting,

大气科学进展 , 2011,
Abstract: In this paper, firstly, the bias between observed radiances from the Advanced TIROS-N Operational Vertical Sounder (ATOVS) and those simulated from a model first-guess are corrected. After bias correction, the observed minus calculated (O--B) radiances of most channels were reduced closer to zero, with peak values in each channel shifted towards zero, and the distribution of O--B closer to a Gaussian distribution than without bias correction. Secondly, ATOVS radiance data with and without bias correction are assimilated directly with an Ensemble Kalman Filter (EnKF) data assimilation system, which are then adopted as the initial fields in the forecast model T106L19 to simulate Typhoon Prapiroon (2006) during the period 2--4 August 2006. The prediction results show that the assimilation of ATOVS radiance data with bias correction has a significant and positive impact upon the prediction of the typhoon's track and intensity, although the results are not perfect.
Oil Spill Model Operational Application in Damage Assessment and Case Study of Validation  [PDF]
Bing Qiao, Feng Xiao, Ru Lan, Tao Li, Chunchao Li
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.95033
Abstract: Oil spill modeling is an important technical measure to evaluate the impact of oil spills scientifically. Because of the great uncertainty in its early development, simulation results have not been used as the basis of judgments for environmental compensation cases. Despite this, scientific research institutes in many countries, including China, are still devoted to the research and development of oil spill models and their applications in environmental damage assessment, which makes it possible to apply them in the judicial arbitration of damages claims. The relevant regulations on the Chinese compensation fund for oil pollution damage from ships and the judicial authentication of environmental damage have also accredited such kind of modeling applications. In order to enhance the applicability of oil spill model further, it is necessary to expand its damage assessment function, and to test, calibrate and verify the accuracy of the evaluation. To this end, the author adopts the self-developed 3-dimentionaloil spill model—CWCM to simulate the “Tasman Sea” oil spill accident. By comparing the simulation results of tidal current field, wind field, oil spill trajectory with those observed, the model coding and parameter selection are corrected, and it is realized that the simulation being basically consistent with the measured results. In addition, the results of the scale reduced simulation test of oil spill weathering are applied verifying and perfecting the weathering model of CWCM. The technical requirements and process for operational application of oil spill model in judicial arbitration are also put forward. In view of the rapid simulation function, the operational updating program for oil spill weathering model, coupled current model and dynamic update wind field diagnostic model are put forward in order to further improve the operational evaluation function and evaluation efficiency of oil spill model.
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