1. what is one new thing you learned about the jet stream as a result of doing this lesson?
lesson
a current is the nonstop flow of a substance.
flowing river
rivers have currents.
stream near a house
streams have currents.
ocean with a beach in the foreground
oceans have currents.
the atmosphere also has currents. the currents in the atmosphere are made when air moves around. these currents in the atmosphere are called the jet stream.
when you look outside and see that it is windy, is this wind a part of the jet stream? think about this for a second and select your answer below.
text version
the jet stream is commonly used by commercial airlines. the time it takes an airplane to travel on long trips can be greatly decreased by using the winds in the jet stream for extra speed.
so what causes the jet stream? to answer this question, we need to make sure that you understand some properties of air.
hot air is less dense than cold air. this means that cold air weighs more than hot air.
since cold air weighs more than hot air, cold air pushes down with more pressure.
illustration of jet stream
image courtesy of nasa and the university of illinois ww2010 project
the above picture shows how the jet stream is formed. the warm air mass has less pressure than the cold air mass. because there is a difference in temperature and pressure between the two air masses, a current is formed between them.
how does the jet stream influence the weather?
if you were to throw a stick into a river, where would the stick go? the river’s current would determine the direction the stick would go. this idea is very similar to how the jet stream influences weather. the current of air to steer storms.
the jet stream also moves cold air and warm air into places. have you noticed that not every day has the same weather? cold air is brought in by the jet stream on cold days and warm air on warm days.
the jet stream to make currents in the ocean. these currents in the oceans also influence the weather.