cold advection

The main reasons of the freeze injury are long day of snow cover , strong cold advection supplement and low temperature caused by clear air radiation ;

地面积雪时间长、高空强冷平流补充南下与晴空辐射降温是形成此次低温冷害的主要原因；

Adiabatic cooling , negative vorticity advection and cold advection prevented cyclone development .

绝热冷却、负涡度平流和冷平流对气旋的发展起阻碍作用。

Cold advection on upper lever and warm advection on low lever offered stratified conditions .

高层冷平流、低层暖平流提供了层结条件；

Influence of cold advection in MID-AND-UPPER troposphere on squall line occurrence

中上层冷平流对飑线发生的影响

The straw cover and the upper air smog combination is obvious to the cold advection freeze injury defense effect ;

秸杆覆盖与空中烟雾组合对冷平流型冻害防御效果明显；

When the ozone peak value emerges in upper troposphere , there is significant cold advection close to the layer of peak value .

对流层上层和平流层低层出现臭氧峰值时，其峰值层附近具有显著的冷平流特征。

Formed through radiative cooling , the surface fog layer was followed by a cloud layer caused by lowlevel cold advection .

结果表明，此次雾过程首先由地面辐射冷却形成贴地雾层，而后因低空平流冷却形成低云。

It is also emphasized that analysis of horizontal distribution of instability energy and cold advection is useful for forecasting the area in which squall lines occur .

还指出分析不稳定能量和中上层温度平流的水平分布对预报飑线发生的区域是有用的。

With the clockwise movement , the echo disappeared gradually . There is warm advection in the lower and cold advection in the upper in vertical velocity profile map .

从垂直风廓线产品来看，具有低层为暖平流、高层为冷平流的垂直分布特征。

Hail shooting located in the area with convective instability , high energy tongue at the middle low level , warm advection and convergence in low level and cold advection and divergence at the high level , and ascending motion .

冰雹产生在中低层对流不稳定、高能舌和低层暖平流、高层冷平流以及低层辐合、高层辐散的上升运动区。

We must pay attention to the southern warm thermal advection as well as the northern cold thermal advection in the cold front shear type rainstorm process .

在该型暴雨的发生过程中，北部冷平流具有十分重要的作用，但南部暖平流的作用也不可忽视。

It analyzes the impact of angles between airflow direction , mountain axis , and warm ( cold ) advection on the mesolow in North China by adjusting the matched patterns of terrain with wind , temperature and pressure fields .

通过调整风场、温度场、气压场与地形的配置关系，设计多种试验方案。并讨论了气流与山脉交角大小、冷暖平流对华北中低压的影响。

The asymmetrical structure of the middle & low level cold and warm advection is the important factor for cyclone 's development .

在发展阶段，700hPa层以下的温压场的斜压结构是气旋发展的重要因素，当冷平流与暖平流呈现西北&东南的偶极子型时，气旋发展；

The outgrowth of the mesoscale vortexes at low and middle levels could lead to the appearance of smaller scale strong cold and warm advection , which excites the baroclinic development of the mesoscale systems themselves .

中低层中尺度涡旋的形成会导致尺度更小的强冷暖平流的出现，从而进一步激励中尺度系统自身的斜压发展；

The qualitative identification methods of Doppler radar velocity PPI pictures are introduced . The related image features of convective rainfall clouds are analyzed : ① the zero-velocity lines in the wind field related to large-scale convergence or divergence in combination with cold or warm advection ;

介绍了多普勒雷达速度PPI产品图像定性识别方法，分析了与对流性降水云体有关的图像特征：①冷暖平流与大尺度辐合辐散运动相结合的零速度线；

The result shown that the cold ( warm ) advection and convergence ( pergence ) in the velocity data were interrelated with the formation , maintenance , and disappearance of the snow-fall .

结果表明：速度资料中的冷（暖）平流和辐合（散）与降雪的形成、维持和消散关系密切。

The results show that the strong cold air flowing into a warm trough induced the first temperature sudden drop , but the second was resulted in the upper cold advection passing downward and the surface precipitation band moving from west to east .

分析表明，第一次气温陡降是由于地面强冷空气侵入暖槽，第二次气温陡降主要是高空冷平流下传和地面自西向东发展的降水导致；

Cold air converged into the circulation of " Tailim " continually from the west after " Tailim " landed and moved to the northwest , but during the heavy rain time cold air advection did not influence Lushan .

泰利登陆后西北行时不断有冷空气从西部补充到低涡环流之中但强降雨期间庐山低层并未直接受到冷平流影响。