Weather Maps & Fronts • Refers to the state of the atmosphere at a specific time and place. • Influenced by pressure systems (high and low) and fronts. • Describes conditions such as air pressure, wind, temperature, and the amount of moisture in the air. • Is caused by heat energy from the sun.
25
Embed
Weather Maps & Fronts Refers to the state of the atmosphere at a specific time and place. Influenced by pressure systems (high and low) and fronts. Describes.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Weather Maps & Fronts
• Refers to the state of the atmosphere at a specific time and place.
• Influenced by pressure systems (high and low) and fronts.
• Describes conditions such as air pressure, wind, temperature,
and the amount of moisture in the air.
• Is caused by heat energy from the sun.
Air mass
• Large body of air that has the properties similar to the part of Earth’s surface over which it develops.
• Changes in weather result from movement of air masses.
Weather Patterns
Low Pressure System
When air is heated, it becomes less dense– Therefore, it rises, leaving behind an area
where there is less air.– Called a low pressure area– Rising air carries moisture with it. As a result,
low pressure is usually associated with clouds and rain.
– Indicated by a L on a weather map.– Troughs of low pressure are important because
they sometimes lead to the development of a low pressure system. Troughs are indicated by lines (sometimes purple, black or green) with no triangles or semicircles.
High Pressure System
As air cools, it becomes more dense– It falls, creating an area where there
is more air– Called a high pressure area– Very little moisture in this air, so
usually associated with clear, sunny days.
– Indicated by a H on a weather map.
Isobars
Lines that connect points of equal atmospheric pressure.
Isobars close together mean high wind.
Isobars far apart mean light wind.
Isotherms (iso – same, therm – heat)
Lines that connect locations of equal
temperature.
Front
• A boundary between two air masses of different
density, moisture or temperature
• Cloudiness, precipitation and storms may occur at