PPL Flashcards
Explain a ridge, trough and col as it pertains to meteorology.
A ridge is a section of high pressure extending from a system. Winds turn left (in the southern hemisphere). Weather conditions are generally stable.
A trough is a section of low pressure extending from a system. Winds turn right (in the southern hemisphere). Weather is unsettled; rain areas and thunderstorms are common.
A col is an area between two highs and lows. Winds are light and variable with little significant weather.
What significance does the troposphere and tropopause have?
The tropopause is the point at which the troposphere ends (about 18km above the equator and 8km above the poles). Temperature stops reducing at a predicable rate at the tropopause.
The troposphere contains essentially all water vapour, weather, clouds and atmospheric convection.
Sinking air rotates in what direction and creates what kind of pressure system?
Anti-clockwise; high pressure system.
Rising air rotates in what direction and creates what kind of pressure system?
Clockwise; low pressure system.
What are weather conditions generally associated with low and high pressure systems?
High pressure systems consist of sinking air and produce relatively stable and cloud-free air.
Low pressure systems consist of rising air carrying water vapour from the surface. As it rises, it expands and cools eventually forming clouds. If there is enough moisture, large clouds and rain areas develop. Low pressure systems are therefore associated with cloudy and rainy weather.
