the coming together of the cold sectors of air in a depression as the warm sector is lifted from the surface altogether. Two kinds:
cold occlusion - the rear cold sector is colder than the forward one and undercuts both the warm sector and the forward cold sector.
warm occlusion - the forward cold sector is colder and the rear sector pushes the warm sector over the forward cold sector and then rises itself.
Geography Dictionary & Glossary for Students \\ ITS Tutorial School (ITS) - Hong Kong.