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AN EFFICIENT SEQUENTIAL DESIGN FOR sensitivity experiments

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Acta Mathematica Scientia 2010年第1期30卷 269-280页

作者：田玉斌房永飞 Department of Mathematics School of ScienceBeijing Institute of Technology

In sensitivity experiments, the response is binary and each experimental unit has a critical stimulus level that cannot be observed directly. It is often of interest to estimate extreme quantiles of the distribution of these critical stimulus levels over the tested products. For this purpose a new sequential scheme is proposed with some commonly used models. By using the bootstrap repeated-sampling principle, reasonable prior distributions based on a historic data set are specified. Then, a Bayesian strategy for the sequential procedure is provided and the estimator is given. Further, a high order approximation for such an estimator is explored and its consistency is proven. A simulation study shows that the proposed method gives superior performances over the existing methods.

关键词： sensitivity experiments extreme quantiles bootstrap principle Bayesianstrategy sequential design

A Heavy Sea Fog Event over the Yellow Sea in March 2005: Analysis and Numerical Modeling

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Advances in Atmospheric Sciences 2007年第1期24卷 65-81页

作者：高山红林行沈飙傅刚 Physical Oceanography Laboratory Ocean University of ChinaQingdao 266003 Qingdao Meteorology Observatory Qingdao 266003

In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility along the Shandong Peninsula coast to 100 m or much less at some sites. Satellite images, surface observations and soundings at islands and coasts, and analyses from the Japan Meteorology Agency （JMA） axe used to describe and analyze this event. The analysis indicates that this sea fog can be categorized as advection cooling fog. The main features of this sea fog including fog area and its movement axe reasonably reproduced by the Fifth-generation Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model （MM5）. Model results suggest that the formation and evolution of this event can be outlined as：（1） southerly warm/moist advection of low-level air resulted in a strong sea-surface-based inversion with a thickness of about 600 m; （2） when the inversion moved from the warmer East Sea to the colder Yellow Sea, a thermal internal boundary layer （TIBL） gradually formed at the base of the inversion while the sea fog grew in response to cooling and moistening by turbulence mixing; （3） the sea fog developed as the TIBL moved northward and （4） strong northerly cold and dry wind destroyed the TIBL and dissipated the sea fog. The principal findings of this study axe that sea fog forms in response to relatively persistent southerly waxm/moist wind and a cold sea surface, and that turbulence mixing by wind shear is the primary mechanism for the cooling and moistening the marine layer. In addition, the study of sensitivity experiments indicates that deterministic numerical modeling offers a promising approach to the prediction of sea fog over the Yellow Sea but it may be more efficient to consider ensemble numerical modeling because of the extreme sensitivity to model input.

关键词： sea fog Yellow Sea numerical modeling MM5 sensitivity experiments

Impacts of Initial Conditions on Cloud-Resolving Model Simulations

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Advances in Atmospheric Sciences 2008年第5期25卷 737-747页

作者：高守亭 Xiaofan LI Laboratory of Cloud-Precipitation Physics and Severe Storms （ LACS） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Center for Satellite Application and Research Camp Springs Maryland

Impacts of initial conditions on cloud-resolving model simulations are investigated using a series of sensitivity experiments. Five experiments with perturbed initial temperature, moisture, and cloud conditions are conducted and compared to the control experiment. The model is forced by the large-scale vertical velocity and zonal wind observed and derived from NCEP/Global Data Assimilation System （GDAS）. The results indicate that model predictions of rainfall are much more sensitive to the initial conditions than those of temperature and moisture. Further analyses of the surface rainfall equation and the moisture and cloud hydrometeor budgets reveal that the calculations of vapor condensation and deposition rates in the model account for the large sensitivities in rainfall simulations.

关键词： cloud-resolving model initial conditions sensitivity experiments

New Evidences on the Climatic Causes of the Formation of the Spring Persistent Rains over Southeastern China

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Advances in Atmospheric Sciences 2009年第6期26卷 1081-1087页

作者：万日金赵兵科吴国雄 Shanghai Typhoon Institute China Meteorological Administration Institute of Atmospheric Physics Chinese Academy of Sciences

The spring persistent rains（SPR）over southeastern China（SEC）are a unique synoptic and climatic phenomenon in East Asia.A former study has found that the southwesterly flow which lies on the southeastern flank of the Tibetan Plateau（TP）is one of the deflected westerly flows of the TP,and it is suggested to be the direct climatic cause of *** study found that the southwesterly flow is also highly correlated with the sensible heating of the southeastern TP in interannual variability,in addition to having a high correlation in seasonal *** facts suggest that the thermal forcing of the TP is another important climatic cause of *** sensitivity experiments further prove that the mechanical and thermal forcings of the TP are the climatic causes of the formation of the *** the other hand,the Nanling Mountains and Wuyi Mountains（NWM）over southeastern China not only increase the SPR precipitation amount evidently,but also make the SPR rain belt move to the south by blocking the strong southwesterly flow.

关键词： spring persistent rains climatic causes southwesterly flow the Tibet Plateau sensitivity experiments

NUMERICAL MODELING STUDY OF EFFECTS OF EASTERN PACIFIC WARM POOL ON ENSO

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Journal of Tropical Meteorology 2010年第4期16卷 355-362页

作者：岳彩军陆维松李小凡 Shanghai Typhoon Institute of the China Meteorological Administration Laboratory of Typhoon Forecast Technique/CMA School of Atmospheric Sciences Nanjing University of Information Science and Technology Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Center for Satellite Applications and Research Camp Springs

In this study, sensitivity experiments were conducted with the Zebiak-Cane ocean-atmosphere coupled model forced by the wind stress anomaly from the U.S. National Centers for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR） reanalysis data to study the impacts of eastern Pacific warm pool on the formation and development of ENSO events. The effects of climatological mean sea surface temperature of the warm pool on forecast skill during the ENSO events of 1982-1999 are more considerable that those of climatological mean meridional winds and ocean currents. The forecast skill for the 1997/1998 E1 Nifio event is characterized by sensitivity to climatological mean sea surface temperature and anomalies of northerly winds and currents. The forecast skill is found insensitive to climatological mean northerly meridional winds and currents.

关键词： eastern Pacific warm pool ENSO event Zebiak-Cane ocean-atmosphere coupled model sensitivity experiments

A GCM Study on the Mechanism of Seasonal Abrupt Changes

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Advances in Atmospheric Sciences 1994年第1期11卷 51-56页

作者：王会军曾庆存 Institute of Atmospheric Physics Chinese Academy of Sciences LASG Beijing

In this paper the observational studies and some related dynamical and numerical researches on seasonal abrupt changes were reviewed first. Then a speculation that the seasonal variation of insolation and the nonlinear dynamic interaction account for the abrupt changes was put forward and was asserted by a set of GCM sensitivity experiments. The results show that the abrupt changes would exist in case that all the earth surface was grass land and there was no topography. However, many factors may have influences on the abrupt changes. Hence this phenomenon is quite complicated and needs further investigations.

关键词： Abrupt change GCMs sensitivity experiments

NUMERICAL PREDICTION EXPERIMENT OF AN ADVECTION FOG IN NANLING MOUNTAIN AREA

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Acta meteorologica Sinica 2003年第3期17卷 337-349页

作者：樊琦王安宇范绍佳吴兑邓雪娇刘英伟 Department of Atmospheric Sciences Zhongshan University Guangzhou Institute of Tropical and Oceanic Meteorology Macao Meteorological and Geophysical Services

Now more comprehensive cloud microphysical processes have been included in advanced three- dimensional mesoscale meteorological model such as PSU/NCAR MM5 model,so the model can be used in the prediction of *** this paper,MM5 was utilized to simulate an advection fog occurring in Nanling Mountain *** simulated results were compared with the facts obtained by detailed observation *** results showed that the simulation was successful in the following aspects:(1)the formation and development of the fog;(2)the temporal variation of the maximum liquid water content;(3)the diffusion of the cold air,especially the temporal variation of the ground temperature;and (4)the uplift of the air and the formation and development of the low-lever ***,we did some sensitivity numerical experiments and discussed the effects of the radiation,the release of condensation latent heat and the change of soil moisture and temperature on the formation and development of *** success of numerical simulation experiment of fog has proved that the numerical forecasting of fog is promising.

关键词： Nanling Mountain advection fog numerical simulation sensitivity experiments

A NUMERICAL SIMULATION OF THE EFFECT ON CHINESE REGIONAL CLIMATE DUE TO SEASONAL VARIATION OF LAND SURFACE PARAMETERS (PART Ⅱ)

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Acta meteorologica Sinica 2001年第2期15卷 323-332页

作者：孙健李维亮周秀骥 Department of Geophysics Peking UniversityBeijing 100871 Chinese Academy of Meteorological Sciences Beijing 100081

The effect on climate due to seasonal variation of vegetation and roughness length was simulated in Part Ⅰ of this *** Part Ⅱ,the individual effect of albedo and the joint effect of all those factors (vegetation,roughness length and albedo) were calculated by numerical sensitivity *** results showed that:(1)There is no significant effect on precipitation if the albedo of 4 seasons is used to replace the CRCM's climate average data,but the effect on land surface temperature can be seen *** the effect also can be seen in adjacent regions.(2)If all these three factors are used to replace the CRCM's climate average data at the same time,the effect on precipitation is significant,the most variation value is *** the effect on temperature is similar to what we can see if only one of these factors in CRCM is replaced by monthly or seasonal data.(3)Seasonal variation of land surface parameters has important effect not only on regional climate,but also on global environment.

关键词： land surface process sensitivity experiments regional climate model vegetation roughness length albedo

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A Heavy Sea Fog Event over the Yellow Sea in March 2005:Analysis and Numerical Modeling

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A Heavy Sea Fog Event over the Yellow Sea in March 2005:Anal...