Weather Flashcards
(35 cards)
What is the atmosphere
A thin layer of gases that surrounds the Earth
What percent of the atmosphereis nitrogen
78%
What percent of the atmosphere is oxygen
21%
What percent is made up of other gasas (CO2 and Argon)
Less that one percent
What is the function of the atmosphere
To insulate the Earth from extreme temperatures. It traps heat and also protects the Earth from dangerous rays from the sun
How thick is the atmosphere
480km but most of its within 16km
The troposphere
-reaches from ground level to about 17km
-Weather and clouds occur here
-the temperature decreases as the altitude increases
The Stratosphere
-extends from 17km to 50km
-the ozone layer is here
- some of the highest clouds can be found in the lower stratosphere
What is the Earth’s main source of heat
Solar energy from the sun
What is solar radiation
Energy that travels throughout space from the sun . It is transmitted in the form of light and heat
What are lines of latitudes
The lines around the earth that measure the distance from the equator and extend to thee poles
Why are areas closer to the equator warmer than areas closer to the poles
Because of the earths round shape, the equator is closer to the sun
-the suns rays have a shorter distance to travel to the equator so the heat here is more intense
-the rays at higher altitudes are slanted and cover larger areas and are less intense
What is wind
The movement of air over the surface of the Earth
What causes wind
The unequal heating of the atmosphere and the Earths surface leads to movements of air
How is low pressure at the equator created
When air is heated, it expands making it lighter and so it rises, creating low pressure at the equator
How is there higher pressure towards the poles
Between 30 degrees and the equator, most of the cooling, sinking air moves back towards the equator. The rest of the air flows towards the poles
Global winds : Trade winds
-movements towards the equator
-warm steady breezes that blow almost continuously
-curve towards the west due to coriolis affect(rotation of the earth on its axis)
Global winds : The Doldrums
-area of calm weather
-the trade winds coming from the north and the south meet near the equator
-because they’re heated, they converge and blow upwards
-little wind near the surface of the earth in this area
Global winds : The Aesterlies
-between 30 and 60 degrees latitude
-move towards the poles and curve to the east
-come from the east
-main wind type in Ireland
Global winds : Horse latitudes
30 degrees north and south of the equator
-form a belt that blows between the trade winds and westerlies.
-weak and clear bright weather
Global winds : polar easterlies
-60degrees latitude
-the westerlies meet the polar easterlies.
-form when the atmosphere over the poles cools
-cool air then sinks and spreads over the surface
-come from the east, go to the west
What are currents
The movement of water
What causes currents
-difference in temperature
-earth rotating on its axis
-wind
Warm currents
-from the equator
-Gulf stream(gulf of mexico) turns north-eastwards into the Atlantic Ocean, where it splits to form the wartm North Atlantic Drift and cold Canary current
