Weather and Climate Change 

Extreme weather

Measuring weather.

Wind

Beaufort Wind Scale

Beaufort Force	Wind Speed (KPH)	Spins	Indicators	Terms Used in NWS Forecasts
0	0-2	0	Calm; smoke rises vertically.	Calm
1	2-5	10	Shown by direction of wind smoke drift, but not by wind vanes.	Light
2	6-12	40	Wind felt on face, leaves rustle; ordinary vanes moved by wind.	Light
3	13-20	80	Leaves and small twigs in constant motion; wind extends light flag.	Gentle
4	21-29	130	Raises dust and loose paper; small branches are moved.	Moderate
5	30-39	190	Small trees in leaf begin to sway; crested wavelets form on inland waters.	Fresh
6	40-50	250	Large branches in motion; whistling heard in telephone wires; umbrellas used with difficulty.	Strong
7	51-61	320	Whole trees in motion; inconvenience felt walking against the wind.	Strong
8	62-74	390	Breaks twigs off trees; generally impedes progress.	Gale
9	75-87	470	Slight structural damage.	Gale
10	88-101	550	Seldom experienced inland; trees uprooted; considerable structural damage occurs.	Whole gale
11	102-116	640	Very rarely experienced inland; accompanied by widespread damage.	Whole gale
12	117 or more	730+	Very rarely experienced; accompanied by widespread damage.	Hurricane

Wind speed - Making an anemometer.

MATERIALS

1. 1. straws 
2. 2. pin  
3. 3. Styrofoam Cup  
4. 4. pencil  
5. 5. cardboard straws  

STEPS

1. Tape the straws together.
2. poke the pin threw the straws and into the rubber from the pencil. 
3. put the ends of the straws threw the Styrofoam cups and tape the ends together with the cup.
4.  time and count the for as many times the cups spins.
5.  go twice inside
6. go twice outside

Once you have made an anemometer we are going to record the wind speed.

Group size: 5

Anemometer (above) 

• Timekeeper
• Counter
• Recorder
• Anemometer Manager
• Wind generator

1. Mount the anemometer in a place that has full access to the wind from all directions.
2. When the time keeper says "Go", the counter in each group will count how many times the marked cup passes them in one minute and write it down.
3. If possible, repeat the above step four (4) times and record the average number of spins on the chart.

FINDINGS

• Record how many times it spins using the table below.

You will need to create the wind yourself by blowing. Get 4 different wind speeds by blowing.

You will need to time them and count the number of spins.

	Time Interval	Number of Spins
1.	10 secs	6
2.	10 secs	5
3.	10 secs	8
4.	10 secs	10

• Can you make a statement connecting the number of spins of your anemometer and the speed of the wind? When using this anemometer, 10 turns per minute means the wind speed is about one mile per hour. ... For example, "when our anemometer read 20 spins a minute, the commercial anemometer read 2 miles per hour." Blow on the anemometer or turn an electric fan on low to make sure that it spins easily.