Backround Information

Josh Johnson

BACKROUND INFORMATION

During Minnesota winters many hockey families like to build ice skating rinks in their backyards. There are a lot of different ways to construct an ice rink and it seems like everyone has his or her own theory. For example, John Buccigross from ESPN talks about how he uses a white liner for his rink and needs to buy a new one every year1. Another method, according Backyard Rink Tips, is to use a sprinkler to put water down for the rink2.

The big decision people have to make is whether they will put something on the ground before flooding. Some put material, like a tarp, on the ground before they flood their rink. Others wait for it to snow and then apply the water directly to the snow.

People who put tarps down think they will have ice quicker because they don’t have to wait for it to snow or for the ground to freeze before flooding. The reason for this is to prevent the water and dirt from mixing together and making mud. It would take longer for muddy water to freeze, and the ice wouldn’t be very clear or smooth.

However, there is a debate about what color of tarp is best for keeping ice frozen in the sunlight. Some people believe that one color tarp will help the ice stay frozen longer than another color tarp will. Specifically, colors that are darker, like black or blue, will absorb more light than lighter colors. But, most people use clear plastic because it is easy to find. Others use white. Some use dark because it is the least expensive.

Lighter colors don’t get as hot as darker colors in sunlight because darker colors absorb more sunlight. For example, black top driveways get hotter than white sidewalks on hot sunny days3. This happens even when ice is on top of something. The sun is able to penetrate through the snow and ice on a blacktop driveway more quickly than a white sidewalk.

Similarly, a white tarp under ice doesn't attract sunlight or heat as quickly and is great for ice rinks even when the sun is shinning4. However, darker tarps absorb light, and when an object absorbs light, it creates heat. This is because light is energy and energy makes the object hotter5. If a tarp absorbs most of the light hitting it, the tarp will heat up quickly, which will melt the ice. Heat is not good for an ice rink.
PURPOSE

The purpose of this project is to demonstrate what product is best for keeping an ice rink frozen by experimenting with dark and light colored materials. Model ice rinks will be made (each with a different material under the ice) and placed under a light. Observations and measurements will be recorded. This will help people know what type of product is best for keeping their ice rink frozen in the sun as the temperature changes.
HYPOTHESIS

The rinks with the lighter materials (tarps and snow) under the ice won't melt as quickly as the rinks with darker materials (tarps and dirt). The lighter colors will reflect the light away, so the light won't heat up the ice and melt it as quickly. The rinks with the darker materials will melt more quickly. The darker color will absorb more of the sunlight, which will create heat. The heat will melt the ice more quickly. Specifically, the amount of water produced by the light will be in this order (least amount of water to greatest):

1. White tarp

2. Snow

3. Yellow tarp

4. Blue tarp

5. Clear tarp

6. No tarp (dirt)

7. Black tarp

MATERIALS

· 7 (22.8cm x 33cm) Chefmate cake pans.

· 1 white tarp that is 32cm x 42cm

· 1 blue tarp that is 32cm x 42cm

· 1 yellow Cover all Heavy Weight Storage Bag (32 x 42cm)

· 1 black Contractor bag that is 32cm x 42cm

· 1 clear tarp that is 32cm x 42cm

· A Craftsmen Clamp Worklight that is 250 watts halogen with tri- pod.

· A freezer

· 2 L of water per pan.

· 3/4 L of dirt for the bottom of each cake pan.

· Table

· Stopwatch

· Pencil

· Notebook

· 1 L of snow

· Thermometer that will measure degrees in Celsius

· Manila paper

· 50mL syringe

· Graduated cylinder

· Beaker

PROCEDURE

Place the manila paper down on the table
Place a cake pan on the center of the paper.
Trace around the pan with a pencil.
Take the light and set it up so the base of the light is 57cm away from where the traced line is. Make sure the light is facing the traced line. It should look like this:

Spread out [??grams of dirt] in a pan. (Level dirt by eye.)
Put the pan in the freezer for 24 hours.
Lay the blue tarp in the pan with frozen dirt.
Pour 2L of water on top of the tarp.
Put the pan in the freezer for 24 hours so the water becomes solid ice. Make sure the water level is even.
Take the pan out of the freezer.
Position the pan onto the paper so the pan matches the traced lines.
Press the button on the light twice so the light is as bright as it can get.
Observe and record the ice every 30 minutes for two hours.
Turn off the light.
Use the syringe to extract as much water as possible from the pan. If you can’t get all of the water in the pan, tilt the pan so all of the water will be at one side of the pan and then extract the remaining water.
Take the temperature of 250mL of the water.
Measure the extracted water using a beaker and a graduated cylinder.
Record amount and temperature of water.
Repeat steps 5-18 using a yellow tarp.
Repeat steps 5-18 using a black tarp.
Repeat steps 5-18 using a white tarp.
Repeat steps 5-18 using a clear tarp.

For ice rinks without tarps:

Spread out 3/4L of dirt in a pan.
Place the pan in the freezer for 24 hours.
Put 1/2 L of water to make a base. (If the 2L of water were put on the dirt, it would be all mud.)
Freeze for 24 hours.
Pour the remaining 1 1/2 L of water in the pan.
Freeze for 24 hours.
Repeat steps 9-18.
Spread out 3/4L of dirt in a pan.
Freeze for 24 hours.
Put 1 L of snow on top of the dirt.
Put 0.2 L on top of the snow. (If 2L of water were put on the snow, the snow would melt.)
Put the pan in the freezer for 12 hours.
Add 0.2 L of water in the pan.
Freeze it for three hours.
Repeat 35-36.
Repeat 35-36
Repeat 35-36
Pour 1L of water in the pan. The ice is solid enough to have 1L of water poured on it; this is why this is done at this point.
Freeze for 24 hours.
Repeat steps 9-18.

DATA

RESULTS

Amount of water melted from ice (mL) / Temperature of water (Celsius)
White tarp / 209 / 0.5
Snow / 214 / 1
Yellow tarp / 277 / 0.5
Clear tarp / 278 / 2
No tarp (just dirt) / 320 / 4
Blue tarp / 329 / 2
Black tarp / 381 / 2

Observations
No Tarp (just dirt) / · 30min: Little amount of water on edges.
· 60min: More water-water is on the edges of the ice. Some water is showing in the center of the ice.
· 90min: Again, much more water around the edges of the ice.
· 120min: A lot of water is showing on the whole rink. There is some mud.
Black Tarp / · 30 min: very little amount of water- water is on edges.
· 60 min: A lot more water on the whole rink.
· 90 min: there is a lot more water than at the 60 minute mark.
· 120min: it looks to be a lot more water than other rinks.
Clear Tarp / · 30min: Very low amount of water on the edges.
· 60min: Much more water everywhere.
· 90min: Again, much more water everywhere.
· 120min: More water everywhere. There is a large amount of water on the edges of the ice.
White Tarp / · 30min: No water.
· 60min: low amount of water on the rink.
· 90min: Only a little more water than the 60 minute mark.
· 120min: More water, especially on the edges. It looks like the rink has the least amount of water.
Blue Tarp / · 30min: barely any water.
· 60min: More water around the edges and a low amount of water in the center of the ice.
· 90min: Much more melting on the whole rink.
· 120: There seems to be a lot more water than the 90 minute mark.
Yellow Tarp / · 30min: Barely any water in a corner. It looks that there is less water than the blue tarp at the 30 minute mark.
· 60min: The whole rink has a low amount of water on it.
· 90min: More water- the edges of the ice melted a lot.
· 120min: More water on whole rink.
Snow / · 30min: No water is seen.
· 60min: whole rink has a low amount of water.
· 90min: There is a lot of water around the edges of the ice rink.
· 120min: Again, there is more water around the edges. Sometime during the procedure: the snow became part of the ice.

CONCLUSION

The general hypothesis was correct. Ice rinks with lighter color materials under the ice resulted in less water and colder temperature than the ice rinks with darker colored materials. However, the results for some individual rinks with materials under the ice were not as predicted. Below is how the ending results were different from the hypothesis.

Hypothesized rank by color/ type of material / Final rank
by amount of water / Final rank by temperature
1. White tarp / 1. White tarp / 1. White tarp
2. Snow / 2. Snow / 1. Yellow tarp
3. Yellow tarp / 3. Yellow tarp / 2. Snow
4. Blue tarp / 4. Clear / 3. Blue tarp
5. Clear tarp / 5. No tarp (dirt) / 3. Clear tarp
6. No tarp (dirt) / 6. Blue tarp / 3. Black tarp
7. Black tarp / 7. Black tarp / 4. No tarp (dirt)

Clearly, a white tarp is the best material to use for an ice rink because it was number one in the least amount of water and maintained the lowest temperature. It will keep the ice frozen the longest.

The rink with white tarp had the least amount of water because the white color reflected the light away and so the light didn’t melt the ice as much as the others. The temperature was one of the coldest because there wasn’t much water on the rink.

The rink with snow under the ice is the second best material because it produced the second least amount of water and it had one of the lowest temperatures. The temperature of the water may have been higher than the rink with the white tarp because there was a small amount of dirt in the water.

Yellow is darker than white, which is why the yellow tarp produced more water than the white tarp. The yellow tarp absorbed a little more heat than the white tarp, which is why there was more ice melted on the rink with the yellow tarp than the one with snow and the white tarp. However, there wasn’t a big enough difference to see a temperature difference.

The prediction that the clear tarp would produce more water than the lighter colored materials was made . because the color of the dirt showing through the clear tarp . However, the dirt might have absorbed a lot of light but the clear tarp was a barrier between the direct and the ice. Therefore, the ice didn’t melt as much as though because the temperature was two degrees because of an error that was made: some dirt got into the water, which raised the temperature of the water.

The dirt absorbed a lot of water, so not all of the water could be extracted and measured. The temperature of the water was much higher than all of the other rinks. This is because there was a lot of dirt in the water, which made the temperature higher.

The rinks with a black tarp and a blue tarp had the most water because they were the darkest materials under the ice. The blue and black tarps absorbed the light, which created heat and melted the ice.

Works Cited

1. Buccigross, John. It's a mad, mad world (and backyard) for us Puckheads. January 7, 2007. [December 11. 2008.] Available from: http://sports.espn.go.com/nhl/columns/story?columnist=buccigross_john&id=2747167

2. McArdle, Tamara. Does the color of ice make it melt faster? July 25, 2006. Department of Physics, University of Illinois at Urbana-Champaign, [December 11. 2008.] Available from: http://van.physics.uiuc.edu/qa/listing.php?id=1659

3. Richard Barrans, Ph.D. Color and Heat Absorption. Date of publication N/A [December 11. 2008.] Available from: