Vocabulary 1
____________ often come with thunderstorms or other types of extreme weather. They usually move from west to east.
Cold Fronts
Warm fronts are often associated with ____________________, where warm air is pressed close to the ground.
high-pressure systems
amount of water vapor in the air.
humidity
mass of warm air that replaces a mass of cold air.
warm front
As the Earth spins on its axis, producing night and day, it also moves about the Sun in an elliptical (elongated circle) orbit that requires 365 days to complete. The Earth's axis is tilted at _____________ and is why we have seasons. When the Earth's axis points towards the Sun, it is ____________ for that hemisphere. When the Earth's axis points away, ________ can be expected.
23.5 degrees
summer
winter
Cold fronts move _________ than warm fronts because cold air is _________, meaning there are more molecules of material in cold air than in warm air.
Faster
more Dense
High-pressure systems usually indicate _____________weather.
calm, clear
____________________ are usually associated with clear weather.
High-Pressure systems
_____________ is a climate pattern where the water in the Pacific Ocean near the equator gets hotter than usual and affects the atmosphere and weather around the world.
El Nino
Because the Earth is round and not flat, the Sun's rays don't fall evenly on the land and oceans. The Sun shines more directly near the equator bringing these areas _____________. However, the polar regions are at such an angle to the Sun that they get little or no sunlight during the winter, causing ________________. These differences in temperature create a restless movement of air and water in great swirling currents to distribute heat energy from the Sun across the planet. When air in one region is warmer than the surrounding air, it becomes less dense and begins to _______, drawing more air in underneath. Elsewhere, cooler denser air _______, pushing air outward to flow along the surface and complete the cycle.
more warmth
colder temperatures
rise
sinks
Strong, powerful cold fronts often take over warm air that might be nearly motionless in the atmosphere. Cold, dense air squeezes its way through the warmer, less-dense air, and lifts the warm air. Because air is lifted instead of being pressed down, the movement of a cold front through a warm front is usually called a ___________.
Low-Pressure System
On weather maps, ____________ are illustrated by blue lines with sharp "teeth" pointing in the direction of the wind.
cold fronts
_____________________ are often associated with storms.
Low-pressure systems
_____________is sort of the opposite of El Niño. During a La Niña, the water in the same area along the equator gets colder than usual. According to scientists, La Niña cycles generally create a _____________hurricane season in the Atlantic.
La Nina
more active
There are two sides to a mountain: wayward and leeward. The wayward side of the mountain is the _______________ and the Leeward part of the mountain is the ________________. Whenever it is raining, the wayward side gets ________. As a cloud goes up the mountain, it keeps raining until there is no more water in the cloud. Now, as the cloud starts to go down the other side of the mountain, there is no more precipitation. So, the leeward side of the mountain ______________. The flat ground on this side of the mountain is dry and humid.
side facing the prevailing winds (upwind).
side sheltered from the wind by the mountain's very elevation (downwind).
the rain
doesn't get any rain (dry)
________________ often cause severe rainfall or thunderstorms.
Low-Pressure Systems
_______________ are illustrated by red lines with rounded bumps pointing in the direction of the wind.
Warm fronts
all forms in which water falls to Earth from the atmosphere.
precipitation
Usually, El Niño brings __________________________. Also, warm ocean currents come farther north and all kinds of tropical fish can be caught in the waters far north along the United States West Coast. El Niño may also bring warmer than normal winter temperatures to the eastern part of the United States.
more rain and higher temperatures
The rotation of the Earth causes an interesting phenomenon on free moving objects on the Earth. Objects in the Northern Hemisphere are deflected to the right, while objects in the Southern Hemisphere are deflected to the left. The _____________________thus tries to force winds to shift towards the right or left.
Coriolis Effect
Warm fronts usually show up on the tail end of precipitation and fog. As they overtake cold air masses, warm fronts move slowly, usually from north to south. Because warm fronts aren't as _________________ as cold fronts, they bring more moderate and long-lasting weather patterns.
dense or powerful
a large volume of air that is mostly consistent, horizontally, in temperature and humidity.
air mass
degree of hotness or coldness measured by a thermometer with a numerical scale.
temperature
____________________ is the rise in temperature that the Earth experiences because certain gases in the atmosphere like carbon dioxide, nitrous oxide, and methane trap energy from the sun.
the Greenhouse Effect
Winds in the United States tend to flow from ______________________. These winds are called_________________________.
West to East
Prevailing Westerlies