cold advection

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。

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。

From the diagnosis we can find that the cause of Winnies transformation is the intrusion of cold air from the middle-upper troposphere and the warm temperature advection in the lower.

通过对物理量的诊断分析发现，对流层中高层冷空气的下沉入侵以及对流层低层的暖平流是热带气旋变性的原因。

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；

Tim located in the rear of a high-level trough and obtained negative vorticity advection, with the effect of the feeble cold air from the east, only formed weak cold front in North China, and precipitation on Liaodong Peninsula was less than 10 mm.

Tim位于高空槽后，获得负涡度平流，在东部弱冷空气作用下，引起台风弱变性，并没有形成气旋，在东北地区被西风槽合并后消失，辽东半岛只出现10mm以下的降水。

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。