What is a 'Jet Stream'?


Jet Streams, Fronts ,

Coriolis Effects

Answer the questions in this ppt on the

4-sided worksheet that contains a copy of each question


Link for this ppt: https://docs.google.com/presentation/d/1zNXSuYVIMHaBJBZmeDHccHDv0TY7u6t60o0Pb1m

THtA/edit?usp=sharing 1

Sample Jet Stream on a winter weekend for North America


“What is a ‘Jet Stream’?”

(p. 548 in text)

● Slim bands of high-speed winds

1. Use the Jet Stream/Airplane Travel article and an internet search to find out how big and fast it is, plus the altitude at which it is found, and then write that for your answer to this question.

- Accurate speeds and altitude: http://bit.ly/1gleUHi

- Use the article to describe thickness and width of Jet Stream

- Great info on page 548 of text

Don’t confuse the weather-related Jet Stream with the ultra-high altitude

Jet Stream discovered by scientists in the 1960’s and discovered by me about 5 minutes ago (8 Mar, 2015) http://1.usa.gov/1Bm6RWR


“What is a ‘Jet Stream’?”


● The Jet Streams are in our upper troposphere and lower 2.________sphere.

(the two lowest layers of the atmosphere.)

3. In which layer of the atmosphere do we live? (in book, or Google it)

4. Does a jet stream exist in the southern hemisphere? If so which way does it move? (might want to answer this one after you look at slide 8)


Why Pay Attention to the Jet Stream?

● Wherever the jet stream happens to be located is where FRONTS typically form.

● FRONTS bring our “weather” to us.

6. Draw pictures of the map symbols that represent a warm front, cold front, and stationary front, as they have been discussed in class (hope you kept your notes).

So if you want to know what the weather is going to be like, it can help if you first identify the type of front coming in, which can be partially determined by the

Jet Stream’s position.


Polar Jet Streams

Form as the result of density differences between cold polar air and warm air of middle latitudes.

7. COLD DOESN’T EXIST as a scientific definition, what should we write instead?

8. List 2 factors from your notes of our class discussion that contribute to the differential heating that makes polar regions generally colder than our latitude.


Polar Jet Streams

Complete this Classzone interactive (ES1906) on the jet stream and then answer the questions below: http://bit.ly/1MlLDx2

9. What do the AVERAGE positions of the jet stream in this picture show? Describe the picture in words, and draw your own version to support your description.

10. How do the 2 Jet Stream positions in the picture relate to our AVERAGE summer and winter weather in Michigan? (think!)


Polar Jet Streams

● Separate warmer subtropical air from cooler polar air.

11. Use your textbook to make a little data chart that lists the types of air masses and their average temperatures and moisture levels. (P. 576 in book)

● Polar Jet Streams move West to East b/c of Coriolis Effect in both the northern and southern hemispheres.

(p. 545 in text and slide 9)

● Recently, the Northern Polar Jet Stream has caused severe, extended duration cold temperatures in the Midwest and

Northern U.S.

( watch http://bit.ly/1E09VX9 and this interactive version of actual recent images of the Jet Stream: http://bit.ly/1Mjf7Kf )

● The Jet Stream is also combining with an El Nino event to warm much of Alaska.

( http://bit.ly/1E09VX9 and http://slate.me/1k4cwZ1 some predictions, like Chicago, Green Bay, and Toronto were wrong due to the unusual Jet Stream pattern this winter, our coldest ever)


Coriolis Effect and Wind/Air Travel

Read about the Coriolis Effect in your textbook on page 545.

12. What is the Coriolis Effect?

13. What causes the Coriolis Effect?

14. In which direction do our LONG DISTANCE winds curve due to the Coriolis Effect?

15. Watch and describe these classzone animations: http://bit.ly/1A5ZQFY and http://bit.ly/1AUddZK

16. On page 547, you can see the wind circulation cells. Notice that the easterlies,

_________________, and trade winds move to the right of the direction of the wind in the circulation cells in the northern hemisphere. In which direction do those winds move in the southern hemisphere?_______________

17. P. 547: Does the pattern for the trade winds in the N and S hemispheres at the equator work well to keep them from “fighting” each other as they circle the globe?

18. P. 547: Which way do the trade winds go?


General Questions

19. Why does the atmosphere get thicker (taller, not denser) when you move from the poles to the equator? (simplest reason, think about the air warming)

20. Looking back at the global winds on page 547, which ones “agree” with the path of the Jet Stream?

21. Knowing that they use the differential heating of the earth to form, what might happen to global circulation cells and wind belts if the temperatures of the earth’s surface waters and land temps change as part of climate change?


26. (I moved this slide up at the last minute) Colder air has been moving into Michigan lately. What is pulling that Arctic air down?

Temperature differences between the Arctic and Midwest temperatures makes a pressure field that confines the jet stream to a tight band around the Arctic

As the Arctic melts, the temp. difference is reduced.

● The meanders of the jet stream become more pronounced

(more noticeably sluggish and also bigger.)

● The more often those meanders occur, the more persistent the regional warmth where the jet stream pulls warm Gulf air northward, and regional cold where it pulls Arctic air south.


22. “What is a Subtropical Jet Stream?”

● Forms in subtropical regions where warm air meets cold air.

● Subtropical jet streams have little change in speed and/or direction throughout the year, and are not wavering anything like the Polar Jet Streams have done in the past, and certainly not like they are wavering for the past 2 years of unusual winters in the northern hemisphere.


Jet Streams and Travel

Complete the Classzone on the “First

Successful Nonstop Balloon Flight around the

World”: http://bit.ly/182puEU (es 1908)

- Be sure to answer the 11 questions as you go along!!!


“Soooo, who cares?”

● AVIATION ORGANIZATIONS: Polar jet streams can cause issues with airplane routes

(possibly good or bad, based on direction of the plane and how strong the plane’s engines are.)

24. It also affects the paths of storms, so it’s of interest to. _____

25. Watch the video about Japanese bombs in WWII. (click on “Japanese”)


To sum it all up...