英语语法分析

The passage is an occluded front and trowal brings a change back to polar air-mass weather.

这一段的锢囚锋和高空暖舌带来与极地空气团天气相反的变化。

Hence its position is indicated separately on some weather maps and it is referred to by Canadian meteorologists as a trowal.

因此，在一些天气图上，它的位置会单独标识，加拿大气象学家称之为高空暖舌。