Name: ___________________________
LAB 6: Measurements of meteorological data and
how to obtain current and past weather data using the World Wide Web
QUESTION 1: MEASUREMENTS WITH METEOROLOGICAL INSTRUMENTS
PART A: ATMOSPHERIC PRESSURE
BAROMETER: Measures atmospheric pressure. The pressure tendency (i.e., whether the pressure is rising or falling) can be determined from the barometer (the last pressures observed) in comparison to the current pressure reading.
1. What is the value of the actual atmospheric pressure:
in hPa?
In inHg?
2. Describe how the atmospheric pressure has changed over the past 16 hours.
Reading at –16:
Reading at –8:
Reading at –4:
Reading at –2:
Reading at 0:
3. Explain the implications of this pressure change in regard to the weather. What kind of weather will result from these changes?
PART B: WIND SPEED AND DIRECTION
1. What is the value of the wind speed:
in m/s?
in km/h?
in mph?
2. What is the wind direction?
PART B: AIR TEMPERATURE
1. Measure the air temperature using the Sherpa atmospheric data center.
NOTE: Be careful about the height and the location of the station where you will record your measurement.
In Celsius:
In Fahrenheit:
2. Measure the air temperature with the glass thermometer.
NOTE: Record your reading at the same location used in question 1.
In Celsius:
In Fahrenheit:
3. Compare the data obtained by the two instruments. What are the reasons for the differences between these two measurements?
4. Compare your temperature data with the other groups by completing the table below.
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Team |
Temperature with Sherpa (include units) |
Temperature with glass thermometer (include units) |
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My data |
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Team 1: |
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Team 2: |
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Team 3: |
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Team 4: |
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Team 5: |
5. Do you observe any differences in the readings (between different teams)? What do you think is causing these differences?
PART C: RELATIVE HUMIDITY
1. Measure the relative humidity using a psychrometer.
Temperature wet bulb:
Temperature dry bulb:
Relative humidity:
QUESTION 2: COMPARISON OF YOUR DATA WITH WWW DATA
1. Complete the first column of the table below by making measurements using the instruments provided. Make sure you record the units of your measurements.
2. Using the WWW, complete the second column (again make sure to record the units). Put the measurements in the same units in both columns so you can compare data.
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In-Class Observations |
WWW data Station used: |
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Date/Time |
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Pressure |
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Pressure tendency |
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Cloud amount (8ths) &Cloud type |
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Wind direction |
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Wind speed |
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Precipitation |
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Temperature |
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Relative humidity |
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Elevation |
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3.Look carefully at the data you collected in the field and on the WWW. Do you see major differences between the two sets of data (data you collected compared to web)?
List the variables that are showing differences:
4. Discuss any differences you observe and suggest possible reasons why these differences occur. Consider BOTH physical reasons (where is the web data coming from, where did you collect your data, etc.) and human errors. Consider also the time difference between observations and the type of equipment used. What will be the effect of these differences?
QUESTION 3: FINDING CLIMATOLOGICAL DATA ON THE WWW
Go to the URL for Lab 6 listed below and follow the instructions to complete the Online Exercise:
http://www.iupui.edu/~geogdept/g108/nmlab6a.htm
NOTE: I suggest you print a paper copy of the web-based portion of this Lab. This will help you to follow up.