A case of mesoscale convective complex(MCC)which evolved into a vortex is documented in this paper.As the MCC entered into the dissipating phase,a well-defined spirally banded structure became visible in the satellite...A case of mesoscale convective complex(MCC)which evolved into a vortex is documented in this paper.As the MCC entered into the dissipating phase,a well-defined spirally banded structure became visible in the satellite image. The blackbody temperature(TBB)of the residual cold-cloud-shield indicates the vortex existed in the layer from 400 to 250 hPa.According to the upper air analysis,the upper level vortex was an anticyclone.The MCC-generated vortex was visualized in the satellite images because it was located in the subtropical high where the wind field was very weak.展开更多
Clear air turbulence(CAT),a meso-or microscale(subgrid scale)phenomenon occurring in synoptic scale flow field at high altitude,is very difficult to be observed by the conventional obser- vation network.Thus it is nec...Clear air turbulence(CAT),a meso-or microscale(subgrid scale)phenomenon occurring in synoptic scale flow field at high altitude,is very difficult to be observed by the conventional obser- vation network.Thus it is necessary to approach an index to predict CAT.But at first,the struc- ture characteristics of CAT should be preanalyzed.In this paper,based on the theoretical and diag- nostic analysis of a case,features for wind profile,energy budget and dynamic mechanism of this case were presented.Furthermore,an objective and quantitative index for CAT forecast was giv- en.The verification for its efficiency was done with both real-time observation data and products from a numerical model.The results are very encouraging.展开更多
Using single Doppler weather radar echo information, this paper presents a technique for recognizing two-di- mensional flow field structure of the severe storm and estimating the divergence, the vorticity, and the int...Using single Doppler weather radar echo information, this paper presents a technique for recognizing two-di- mensional flow field structure of the severe storm and estimating the divergence, the vorticity, and the intensity of wind shear line, and gives some examples.展开更多
基金This study was supported by the National Natural Science Foundation of China,No.49335062.
文摘A case of mesoscale convective complex(MCC)which evolved into a vortex is documented in this paper.As the MCC entered into the dissipating phase,a well-defined spirally banded structure became visible in the satellite image. The blackbody temperature(TBB)of the residual cold-cloud-shield indicates the vortex existed in the layer from 400 to 250 hPa.According to the upper air analysis,the upper level vortex was an anticyclone.The MCC-generated vortex was visualized in the satellite images because it was located in the subtropical high where the wind field was very weak.
文摘Clear air turbulence(CAT),a meso-or microscale(subgrid scale)phenomenon occurring in synoptic scale flow field at high altitude,is very difficult to be observed by the conventional obser- vation network.Thus it is necessary to approach an index to predict CAT.But at first,the struc- ture characteristics of CAT should be preanalyzed.In this paper,based on the theoretical and diag- nostic analysis of a case,features for wind profile,energy budget and dynamic mechanism of this case were presented.Furthermore,an objective and quantitative index for CAT forecast was giv- en.The verification for its efficiency was done with both real-time observation data and products from a numerical model.The results are very encouraging.
文摘Using single Doppler weather radar echo information, this paper presents a technique for recognizing two-di- mensional flow field structure of the severe storm and estimating the divergence, the vorticity, and the intensity of wind shear line, and gives some examples.
