The overtaking other warm air mass by the cold air mass is upthrust as a cold front and this occurs due to the formation of the dene and heavy cold front which leads to the formation of the high pressures and the removal of the warm air mas form below and thus the formation f the thunderstorms, and the development of the frontiers.
<u>The cold air mass is thus dominated in the region and hence the warm air is thrown upwards. Leading the formation of an occluded front when they combine.</u>
They have helped nearby societies because they provided them with a sufficient and reliable water source. This allows them to get enough drinking water and allow them to easily grow their agriculture.
