Chernobyl 2 - Air Currents

Author: Brink Harrison

Time: 1 or 2 days
Preparation Time: 10 min copying overheads and activity sheets
Materials: A leaf-blower or powerful hair dryer
Spray bottles of water
Contaminated Areas in Europe overhead
Hot Spots overhead
Wind Patterns overhead
Map of Regions Around Chernobyl overhead
Distances Activity sheet

Students create a scale model of the affected area of the Chernobyl disaster. Using this scale model, students will simulate the explosion and the resulting uneven dispersal of fallout due particularly to wind direction and weather conditions.


Students will be able to: -

i. Construct a scale model to represent the geographic regions around Chernobyl that were affected by radioactive fallout.
ii. Using data from the Chernobyl event to detail on their scale model which areas where most contaminated.
iii. Model the effect of the winds on the distribution of radioactive materials over their scale representation.

Math Standards
• Use unit analysis to check measurement computations.
• Make decisions about units and scales that are appropriate for problem situations involving measurement.
• Recognize and apply mathematics in contexts outside of mathematics.
• Use representations to model and interpret physical, social, and mathematical phenomena
Problem solving
• Solve problems that arise in mathematics and in other contexts

Teacher Background
This lesson is designed to follow the two days of activities in the lesson Chernobyl 1. However, it can be used as a separate lesson and ties directly into the 9th grade science lesson, Fallout! in the From Global to City Air unit.

If you do not do the Chernobyl 1 lesson, you will need to provide a bit of the history of the Chernobyl accident to the students: On April 26, 1986, due to an unfortunate combination of the poor structural design of the reactor building and catastrophic experimental errors, there was a steam explosion that blew the roof of the #4 reactor building at the Chernobyl nuclear power plant. The subsequent fire caused by the explosion took ten days to extinguish. (For a good picture of the gaping hole in the roof of the reactor building, see figure 4 at www.agls.uidaho.edu/etoxweb/resources/case%20study/Chernob6.pdf)

In the initial explosion a plume of radioactive material was released that reached an altitude of 1.5-7.5 km (0.9-4.7miles). Radiation released from the subsequent fire stayed below 1.5 km (approximately 1 mile). To see how the clouds of radioactive material spread around the northern hemisphere in the days following the accident, look at Figure 1 at www.llnl.gov/str/Robison.html
The amount of radiation released at Chernobyl has been estimated to be around 200 times the amount of radiation released at Hiroshima and Nagasaki combined. (Source: www.agls.uidaho.edu/etoxweb/resources/case%20study/Chernob6.pdf)

Variable winds for days carried much of the Chernobyl radioactive material northward to Scandinavian countries, then westward and southward to other European countries. The resultant wide dispersal of this fallout allowed time for both scavenging and radioactive decay before a small fraction of these invisible radioactive clouds rose and also were blown eastward by the prevailing high-altitude winds. These west winds carried an extremely small fraction of the radioactive emissions from the burning Chernobyl plant clear across Asia and the Pacific to America.
(Source: http://www.survival-center.com/nuclear/nwss/s60p783.htm)

Related and Resource Websites

Teachers of the COEP Summer Workshop trying out the Chernobyl activity.



1. Ask the students if they have ever been in a dust storm or seen a sand storm in a documentary on television or a movie (examples: “The Mummy” or “Hidalgo”).

2. Have the students discuss the wind direction and the velocity of the wind would affect the way the dust moves. Ask what else might affect the way the dust is moved. (The size of the dust particle makes a difference on how far it is carried by the wind.) One big difference between a sand storm and radiation that is being carried by the wind is that you can see the sand being blown; you can’t see the radiation, but it’s there. When the reactor at Chernobyl exploded, it released clouds of radioactive materials that were carried by winds all around the Northern hemisphere. (See Figure 1 at http://www.llnl.gov/str/Robison.html) If the students are doing the 9th grade science lesson, Fallout! in the From Global to City Air unit, they will actually be finding locations in the northern hemisphere where radiation levels increased due to winds carrying radiation from Chernobyl. Another map showing the areas in Europe contaminated by radioactive fallout from Chernobyl can be found at http://www.dhushara.com/book/explod/cher/cher.htm

3. The areas affected by the radioactive fallout in Belarus, Ukraine, and Russia were particularly large due to the high altitude and the long duration,10 days, of the release as well as the changing wind directions. “Hot spots” or areas of significant deposition occurred where the passage of the plume coincided with rainfall, especially in the Belarus, which received over 70% of the fallout. Put up the Hot Spots overhead to show the heavily irradiated areas caused by the fallout from Chernobyl. (Source: http://www.brama.com/ukraine/cbyl.html)

4. Ask the students to discuss what may have caused the hot spots and why the distribution seems so uneven. (The direction of the wind and the amount of rainfall in certain regions caused the radioactive fallout from the radiation plume released at Chernobyl to be spread out very unevenly over areas surrounding Chernobyl. The smaller particles were carried further while the largest particles, primarily fuel particles, were deposited within 100km of the reactor.)

5. To create a radioactive plume and demonstrate how the wind may cause it spread out, use a leaf blower with a sufficiently large “elbow bend” PVC pipe attached to it.

6. Put approximately a cup or more of kool-aid powder into the PVC pipe. Make sure that you are outside before you turn on the leaf blower. If you have an open-air plaza, the air currents should show how some of the particles are carried by the wind and others seem to drop back down to the ground.

7. Tell the students that today they are going to create a model of the Chernobyl disaster to demonstrate how the accident had such a horrendous effect of the regions around the reactor. To show the students the different wind conditions over the days the radiation was released at Chernobyl, see the animated figure 12 at http://www.chernobyl.info/index.php?userhash=1652928&navID=15&/ID=2 or put up the Wind Patterns overhead. Ask the students why there is a 30-km exclusion zone around Chernobyl where nobody is officially allowed to live.

8. Put up the Map of Regions around Chernobyl overhead and pass out copies to the students as well. Tell them that the distance from Chernobyl to Kiev is approximately 80 miles. Ask them how they can use this information to calculate the approximate distances from Chernobyl to the other cities on the sheet.

9. Split the class into groups and have them measure the distance in centimeters from Chernobyl to the cities on the map. Put the distances on the board and have the students put them on the Distances Activity sheet as well.

10. Have the students calculate the distance from Chernobyl to the other cities by setting up an appropriate proportion, and solving for the desired distance.

For example:

11. Bring in a large piece of white paper (poster board paper, etc.) and mark the location of Chernobyl, making sure that there is room to mark the locations of the other cities as well. Tell the students that they need to come up with an appropriate scale to show the approximate location of the other cities on the larger sheet. If you want to be more accurate, have the students determine the direction angle from Chernobyl to the city as well as the distance. Have the students mark the approximate locations of the cities.

12. Using the Wind Patterns overhead, model the spread of the radioactive fallout by using a hair dryer, different colors of Kool-Aid, and the marshmallows. Have the students place the marshmallows on the large map/paper in areas that they believe will receive fallout. For each wind condition represented, ask the students where you should stand and in which direction you should aim the hair dryer. Turn on the hair dryer and have a volunteer sprinkle the Kool-Aid in front of the dryer so that the Kool-Aid is blown approximately in the direction of the wind on that particular day. Repeat this for each of the days shown, using a different color of Kool-Aid if possible. (You might want to check with your janitor before doing this experiment because Kool-Aid is sweet and will probably attract insects. You may need to do it outside.)

13. Once all the fallout has been distributed, ask the students if they could feel or smell the Kool-Aid even though they were not near the map. Ask the students how this can be related to the people who lived in the regions around Chernobyl.

14. Tell the students that on May 1st every year in the former Soviet Union, there are huge parades celebrating Workers of the World Day. On May 1st, 1986, even though the government officials knew that radioactive fallout was in the air, a parade was held in Kiev, only 80 miles away from Chernobyl, with hundreds of children involved. Tell the students that when a Ukrainian minister was asked shortly after the disaster occurred how many children who lived downwind of Chernobyl were safe, he replied, “None.”

15. Have the students look at the marshmallows as well and ask if they see anything different. (Since the marshmallows were dry, it should be hard to see the Kool-Aid on them.) Using a spray bottle with water, spray a fine mist on the marshmallows and the colors should spring out. Ask how this could be related to the people who lived downwind of Chernobyl on each of the days with different wind conditions.

16. Have the students look for hot spots on the map. Ask what might have caused them and ask what other weather conditions might lead to hot spots. (Rain or other forms of precipitation). Ask how they could model this in the experiment the next time.

By seeing how far an area the radioactive fallout from Chernobyl covered, the students should begin to realize the seriousness of the Chernobyl disaster.

Based on UN official reports, up to 9 million people in Belarus, Ukraine, and Russia have been directly or indirectly affected by radiation fallout.
(Source: http://www.wagingpeace.org/menu/action/urgent-actions/chernobyl)

1. How are people indirectly affected?

2. You are a farmer who lived downwind of Chernobyl, and you had been evacuated from the farm that had been in your family for generations to a city. You know nobody in the city and have little chance of finding employment. The government has help programs, but they don’t have enough funding to help everybody. What would you do?

3. Many forms of cancer take years to appear. You were born in Kiev and lived there when the Chernobyl accident occurred. You know that you have been exposed to radiation and that the food brought to market from farmers may have been exposed to radiation from the air, water, or ground. But you wouldn’t be able to have the type of life have you have in Kiev if you move somewhere else. Is it worth staying there and leading your normal life?

4. Think of a couple more examples of how people might be directly or indirectly affected.

Embedded Assessment
Students should be assessed during the calculation part of the lesson on their ability to use proportions to determine the approximate distances from Chernobyl to different cities. The discussion following the model “explosions” should have the students thinking about how Chernobyl has affected so many people, including those who were not born at the time of the accident.

Embedded Assessment
























































PULSE is a project of the Community Outreach and Education Program of the Southwest Environmental Health Sciences Center and is funded by:

NIH/NCRR award #16260-01A1
The Community Outreach and Education Program is part of the Southwest Environmental Health Sciences Center: an NIEHS Award


Supported by NIEHS grant # ES06694

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Last update: April 10, 2008
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