Materials and Equipment

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Option 1: Weather and Climate in Your
Neighborhood
Time Required
Very Short (≤ 1
day)
Prerequisites
None
Material Availability
Readily available
Cost
Very Low (under
$20)
Safety
No issues
Abstract
Do you live in an area where the weather changes a lot from season to season throughout the year? Or
do you live in a place where the weather stays pretty much the same all year long? How dynamic is the
weather, and how does it compare to climate? In this experiment you can use the Internet to conduct your
own investigation about how climate and weather in your local area change over time.
Objective
In this experiment you will investigate patterns and variations of weather and climate in your local area by
comparing historical weather data for your city.
Introduction
What is the difference between climate and weather?
Weather is very dynamic, and may change many times from day to day or from season to season.
Changes in weather take place over a relatively short period of time, like hours or days. A sudden
thunderstorm, a blizzard, or a hot day are all examples of weather.
Climate, on the other hand, is historically very stable, and describes weather patterns of many years in a
particular region. Climatic change takes place over long periods of time, like several years or decades.
Some types of climatic changes occur over even longer periods of time, like hundreds, thousands, or
even millions of years. In fact the Great Ice Age is one example of a period of climatic change.
In this experiment you will investigate the difference between weather and climate by using a historical
weather database. How are changes in weather and climate measured? By tracking changes in
temperature from month-to-month and year-to-year, you can test for patterns in weather and climate.
Which is the most dynamic? Which is the most stable?
Terms and Concepts
To do this type of experiment you should know what the following terms mean. Have an adult help you
search the Internet, or take you to your local library to find out more!

climate

weather

temperature

season

degrees Fahrenheit (°F)

degrees Celsius (°C)

weather station
Materials and Equipment

computer with Internet connection

pencil and paper for recording data
Experimental Procedure
1. You will be using the Internet to look up historical temperature data from your local area, so grab
a pencil and paper to write down your data.
2. First you need to decide what historical dates you will use. The database contains monthly
averages for many localities back until 1958. You can pick the last 12 years, or use data from 20
years ago, depending upon which data is available for your city.
3. Choose a series of months and years that you will use to look up the average temperature
recorded. Decide how you will organize and record your data in a data table. For example:
Average Temperature for Each Calendar Month During the Years 1994-2005:
200
5
200
4
200
3
200
2
200
1
200
0
199
9
199
8
199
7
199
6
199
5
199
4
January
February
March
April
May
June
July
August
Septemb
er
October
Novemb
er
Decemb
er
4. Now, get on your computer, connect to the Internet and open up your Web browser.
5. Type the URL, or Web address, for "The Weather Underground" website into the navigation bar:
http://www.wunderground.com/
6. At the top, left-hand corner of the page there will be a box where you can type in your city and
state to find your local weather. Type in your city and state, or your zip code, and then click on the
search button.
7. About halfway down the page, you will see a box that says, "History and Almanac". In this box
you will see the "Detailed History & Climate" option with today's date, click on the "Go" button.
8. A detailed History for your local weather station will appear on your screen, followed by a daily
summary table. Just above the Daily Summary will be a series of output options: Daily, Weekly,
Monthly, etc. Click on Monthly.
9. Now, using the drop down menu, choose the month and year you want to collect data for, then
click "Go."
10. When the new window appears, you will see "Summary," a table full of data for weather during
that month in your city. Look for the box that tells you the Average Mean Temperature, use this
example to help you find it:
11. Write down the data on your data sheet, and continue to collect data for each of the other months
and years on your data sheet. You can do this by changing the month or year in the drop down
menu above your Summary table and clicking on "Go."
12. After you collect data from each month and year, you are ready to make graphs and to look for
any trends. You will want to make at least two types of graphs. Choose a year and graph the
temperatures for each month of that year. Choose a month and graph all of the temperatures for
each year of data.
13. For a more advanced graph, you can make a summary graph of the monthly temperatures over a
one year cycle by superimposing the data for different years on the same graph.
14. Has the average temperature for your area decreased or increased over the years? Has the
average temperature fluctuated or remained constant from month-to-month or year-to-year? Are
there any recurring patterns or cycles? Do these changes reflect changes in weather or climate?
Option 2: How Does a Wind Meter Work?
Time Required
Very Short (≤ 1 day)
Prerequisites
None
Material Availability
Readily available
Cost
Very Low (under $20)
Safety
None
Abstract
On a windy day it is hard to keep your hat on! The power of the wind can even be strong enough to power
large wind turbines to make electricity! In this experiment, find out how you can make your own
instrument to measure the speed and power of the wind. How does it work?
Objective
In this experiment you will investigate how the speed of the wind is measured by an anemometer.
Introduction
Weather is happening all around us every day. But isn't it nice to know the weather ahead of time?
Suppose you have a soccer game this weekend, what is the chance of rain? When you watch the
weather forecast on the local news, you are watching the results of weather data that has been gathered
by a meteorologist, who will use the data to try and
predict the weather.
A meteorologist measures weather patterns in the
atmosphere to predict the weather forecast ahead
of time. To track changes in the weather, a
meteorologist uses weather instruments at a
weather station. There are many different weather
instruments, each made to measure a different
feature of the weather:

a thermometer to measure temperature

a barometer to measure air pressure

a hygrometer to measure humidity

a rain gauge to measure precipitation

an anemometer to measure wind speed

a wind vane to measure wind direction
Click here to watch a video clip from a
CYBERCHASE episode related to this Project
Idea. Presented by pbskidsgo.org.
An anemometer is used to measure wind speed. Speed is how fast or slowly something is moving. But
what exactly is wind? Wind is movement in the air that can be seen or felt. Wind occurs when air moves
from a high-pressure area (where there are more molecules) to a low-pressure area (where there are
fewer molecules). Watch the CYBERCHASE episode, by PBS KIDS GO!, on the right and watch as the
CyberSquad heads to the Northern Frontier to solve a mystery by measuring and comparing wind
speeds! Then get ready to test winds yourself. In this experiment, you will make your own wind meter, or
anemometer. An anemometer is useful because it rotates with the wind. To calculate the speed, or
velocity, at which your anemometer spins, you will determine the number of revolutions per minute
(RPM), or how many times the anemometer spins a full circle from where it started in one minute. To test
your anemometer, you will set a fan at different speeds and count the revolutions per minute of your
home-made anemometer. How well will it work?
Terms and Concepts
To do this type of experiment you should know what the following terms mean. Have an adult help you
search the internet, or take you to your local library to find out more!
 atmosphere
 anemometer
 speed
 wind
 revolutions per minute
Questions

How does an anemometer work?

Will high speed winds increase or decrease the number of turns of an anemometer?

How can the number of turns and length of time be used to calculate wind speed?
Materials and Equipment

5 three ounce paper cups (Dixie Cups)

2 soda straws

pin

paper punch

scissors

stapler

sharp pencil with an eraser

a fan with at least three different speeds (high, medium, and low)

ruler (optional)
Experimental Procedure
1. Take four of the paper cups and use the paper punch to punch one hole in the side of each cup,
about a half inch below the rim.
2. Take one of the four cups and push a soda straw through the hole. Fold the end of the straw and
staple it to the side of the cup across from the hole. Repeat this procedure for another one-hole
cup and the second straw.
3. Take the fifth cup and punch four equally spaced holes in the side of the cup, about a quarter inch
below the rim. Then punch a hole in the center of the bottom of the cup.
4. Slide one cup and straw assembly through two opposite holes in the cup with four holes. Push
another one-hole cup onto the end of the straw just pushed through the four-hole cup.
5. Bend the straw and staple it to the one-hole cup, making certain that the cup faces the opposite
direction from the first cup. Repeat this procedure using the other cup and straw assembly and
the remaining one-hole cup.
6. Align the four cups so that their open ends face in the same direction either clockwise or counterclockwise around the center cup.
7. Carefully push the straight pin through the two straws where they intersect.
8. Push the eraser end of the pencil through the bottom hole in the center cup. Carefully push the
pin into the end of the pencil eraser as far as it will go. You may need an adult to help you push
the pin in.
9. Now your anemometer is ready for use! It should look like Figure 1 below:
Figure 1. When your anemometer is completely assembled, it should look
like the one in this picture.
10. Now set up the fan on one side of the room and mark a line with tape on the other side of the
room from the fan, about 6–8 steps away.
11. Turn the fan on low speed and stand on the line across the room. Hold up your anemometer and
count the number of turns your fan makes in a minute. This is its revolutions per minute (RPM).
Get someone to help you time the minute with a kitchen timer so that you can do the counting.
12. If you find that the anemometer is moving too fast for you to count then you will need to increase
your distance and try the experiment again. Remember, all of your data needs to be collected
from the same distance for each speed, as a control.
13. Repeat step 11 for the other speeds of the fan (medium and high), each time taking at least three
different readings and averaging the results. You can calculate the average by adding the three
readings together for a fan speed and dividing the answer by three. You should keep your data
organized in a data table like Table 1 below.
Wind Speed in Revolutions per Minute (rpm)
Fan Speed
1st Reading
2nd Reading
3rd Reading
Average
Low
Medium
High
Table 1. You should write down your data in a table like this one.
14. Now you need to make a graph of your data so you can analyze your results. On the left side of
the graph (y-axis) put a scale for your anemometer readings in revolutions per minute. On the
bottom of the graph (x-axis), put a mark for each of the different fan speeds (low, medium, high).
Then draw a bar for the average reading for each of the fan speeds.
15. How did your anemometer work? What happens to the number of turns of the anemometer in
revolutions per minute as the wind speed increases?
Option 3: How Does Atmospheric Temperature Affect
the Water Content of Snow?
Time Required
Longer
Prerequisites
You'll need to collect snow from many snowfall events for this project, so you
will need cooperation from the weather and an area outside where you can
gather undisturbed snow from each snowfall. You will also need a computer
with Internet access to gather atmospheric temperature data.
Material Availability
Readily available
Cost
Very Low (under $20)
Safety
No issues
Abstract
Are you a snow aficionado? What atmospheric conditions produce light, powdery snow, and what
conditions produce heavy, wet snow? This project shows you how to use data from daily balloon
soundings of the atmosphere and your own snow measurements to find out.
Objective
The goal of this project is to investigate the effect of atmospheric temperature on snowfall depth.
Introduction
If you're lucky enough to live in a place that gets snow in winter, you know that the feel of the snow can
vary a lot. Sometimes it can be light and fluffy, and other times heavy and wet. The light, fluffy snow has
less water content than the heavy snow. What accounts for these differences?
One possibility might be the temperature of atmosphere in the clouds where the snow forms. Another
possibility might be the temperature of the atmosphere through which the snow falls on its way to the
ground. You may be wondering, "How in the world am I going to measure the temperature of the clouds?"
Fortunately, you don't have to make the measurements yourself. The National Oceanic and Atmospheric
Administration (NOAA) has already done it for you. Twice a day all over the U.S., weather balloons are
used to take atmospheric soundings. The data from these soundings is available online (Unisys Corp.,
2005).
Figure 1 shows an example of an upper air sounding plot. This is a standard graph used by
meteorologists to analyze data from a balloon sounding. There is a lot of additional information in the
graph, but basically it is a plot of temperature (x-axis) vs. height (y-axis). The white data line on the left
shows the dewpoint vs. pressure, and the white data line on the right shows the temperature vs.
pressure. The pressure (in millibars, mb) is shown on the y-axis in blue lettering, and the height (in m) is
shown in white lettering. A sounding plot is also called a "Skew T" plot, because the temperature axis is
plotted at an angle (i.e., skew) of 45°. The temperature lines of the Skew T are in blue (at 45°).
Figure 1. Example of an upper air sounding plot from the Unisys Weather webpage. Data shown are from
International Falls, MN, March 23, 2007.
Atmospheric pressure decreases with height above the Earth's surface. The higher you go, the less
atmosphere remains above you, so the pressure decreases. "Meteorology uses pressure as the vertical
coordinate and not height. This works out better for thermodynamic computations that are done on a
regular basis. Pressure decreases in the atmosphere exponentially as height increases reaching 0
pressure in space. The standard unit of pressure is millibars (mb or hectopascals-hPa) of which sea level
is around 1015 mb. Here is a table of pressure levels and approximate heights (Unisys Corp., 2001):"
Pressure
Approximate Height
(mb)
(m)
Approximate Temperature
(ft)
(°C)
(°F)
1015
(sea level)
0
0
15
59
1000
100
300
15
59
850
1500
5000
5
41
700
3000
10000
−5
23
500
5000
18000
−20
−4
300
9000
30000
−45
−49
200
12000
40000
−55
−67
100
16000
53000
−56
−69
Figure 2 shows how to read the temperature at a chosen pressure level (height). On the y-axis, find the
pressure level (in mb) where you want to know the temperature. Follow the horizontal pressure line over
until it intersects with the temperature plot (right-hand data plot, in white). Then follow the 45° temperature
line down and to the left to the temperature axis. In the example below, the temperature at 700 mb was
about −11°C.
Figure 2. Reading the temperature of the atmosphere at 700 mb (3022 m) from the sounding plot. Follow
the horizontal pressure line to where it intersects with the temperature plot (right hand data line, in white).
Then follow the 45° temperature line down and to the left to the temperature axis. In this example, the
temperature at 700 mb was about −11°C.
There is a lot more information in the sounding plot, but it isn't important for this project. If you want to
learn more about sounding plots, see the references in the Bibliography section.
In this project you will use atmospheric sounding data combined with your own measurements of the
snow depth to liquid ratio to find out if there is a relationship between atmospheric temperature and snow
quality.
Terms and Concepts
To do this project, you should do research that enables you to understand the following terms and
concepts:

troposphere,

pressure,

temperature,

snowflake structure.
Questions

Where does snow typically form in the atmosphere?
Materials and Equipment
To do this experiment you will need the following materials and equipment:

tall cylindrical can for taking snow samples,

flat cover for the can (could be plastic or sheet metal),

a place to collect undisturbed snow from a snowfall event,

a ruler,

computer with Internet access.
Experimental Procedure
1. After a snowfall, pick a location to collect snow that will represent the average snow depth for the
event.
2. Place the can upside down and push it down through the snow until it reaches the ground
surface.
3. Cover the opening of the can with your plastic or sheet metal cover.
4. Bring the can upright, carrying the snow with it. The accumulation of snow in the can should be
similar to what is on the ground.
5. Measure the snow depth on the ground (in cm), close to where the sample was taken.
6. Bring the can inside and wait for the snow to melt.
7. Measure the depth of the liquid water in the can (in cm).
8. Calculate the ratio between the snow depth and the depth of the liquid water. For example, if the
snow depth was 30 cm and you measured 2 cm of liquid water in the can after melting, the ratio
would be 15:1 (15 cm of snow for every cm of liquid water).
9. Repeat the measurement for several snow events.
10. For each snow event, you will also need to examine the upper air sounding that is closest to your
location and to the time of the snowfall event.
a. Examine the temperature profile for the lower troposhpere (surface to 700 millibars
pressure).
b. Upper air sounding plots are available here: http://weather.unisys.com/upper_air/skew/
(Unisys Corp., 2005).
c.
Click on the map location that is closest to where you are.
d. Sounding data is taken twice a day for each station, at noon and midnight.
e. At the Unisys Weather site, data is available for a 36-hour time window: the current
sounding, plus the last the three soundings. This means that you will have to go online
and print out the sounding data within one day of the snowfall event!
f.
See the Introduction for instructions on reading the sounding plot. Further information is
available online (Unisys Corp., 1998; Unisys Corp., 2001; Millersville University LEAD
Undergraduates, date unknown).
11. Is there a relationship between the temperature in the lower troposphere at the time nearest to
the snowfall and the snow depth:liquid depth ratio? To find out, make graphs of snow:liquid ratio
(y-axis) vs. atmospheric temperature for different pressures.
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