Download Weather instruments

Name___________________________________________________________Date________________
Weather Instruments
In order to understand the weather and how it changes it is important to record characteristics of the
atmosphere. There are a number of important elements of weather that meteorologist constantly record
to help understand and predict the weather. We will be recording weather data every day for the next
week and seeing how these factors relate to our weather.
Elements of Weather
Using the exploring Earth’s Weather textbook, read about each element of weather and write a short
description of it. Also, find what instrument is used to measure it.
Weather
Description
What instrument is
Describe how the
element
used to measure it?
instrument works
Air pressure
Temperature
Wind speed and
direction
Relative
Humidity
Cloud cover
Precipitation
We will now go outside and measure relative humidity. Record the information below as shown by your
teacher.
Location
Dry bulb
Wet bulb
Difference between dry
Relative humidity
temperature
temperature
and wet bulb
temperature
Inside
Outside
Answer these questions from our discussion in class.
1. What happens to the water on the thermometer when you are spinning it around?
2. What does water do when it evaporates off of a surface (like your skin)?
3. Why does the temperature of the wet bulb drop?
4. Will more or less water evaporate if the air is drier?
5. Will the wet bulb temperature drop more or less if the air is drier?
6. Will drier air have a lower or higher relative humidity?
7. Which can hold more water, warm air or cold air?
8. What happens to warm moist air when it rises?
Below you will keep a record of these elements of weather on a daily basis. Record the data in the table.
Weather Factor
Day #
Data (date/measurement)
Air Pressure
(in Hg)
Temperature
(degrees F)
Wind Speed
(mph)
Relative Humidity
%
Dew Point
temperature
Precipitation
Mastery Check Questions:
1. What instrument is used to measure temperature, pressure, wind, and humidity?
2. What is relative humidity?
3. Explain the process of forming clouds and rain.
Name_____________________________________________________Period_____
Graphing Elements of Weather
Graphing data helps us to see patterns between different variables. In this activity you will make 3
different graphs and look for patterns between different weather elements.
Graph #1 – Air Pressure vs. Temperature
Using the data from your daily measurements, graph temperature vs pressure. Put the day number on
the x-axis and pressure and temperature on the y-axis (one on the left and one on the right).
1. How are temperature and air pressure related? (Hint: Look for areas on the graph where they are
either increasing or decreasing)
Review questions:
2. What kind of weather is usually associated with low pressure?
3. Draw a diagram that shows how air circulates around a low-pressure system.
4. Air always moves from _____________ pressure to ________________ pressure.
5. What are two ways that pressure can be reduced?
6. How does temperature affect air pressure?
Graph #2 – Relative Humidity vs. Temperature
Using the data from your daily measurements, graph relative humidity vs temperature. Put the day
number on the x-axis and humidity and temperature on the y-axis (one on the left and one on the right).
7. How are air temperature and relative humidity related? (Hint: Look for areas on the graph where
they are either increasing or decreasing)
8. What could explain the pattern between air temperature and relative humidity?
9. Which can hold more water vapor, cold air or warm air?
10. Why does relative humidity increase when temperature increases?
11. What happens when warm, moist air rises?
Graph #3 – Relative Humidity vs. Dew Point
Using the data from your daily measurements, graph relative humidity vs dew point. Put the day number
on the x-axis and relative humidity and dew point on the y-axis (one on the left and one on the right).
Remember that dew point is the temperature at which the air can’t hold any more water. At this
temperature water will start to come out of the air and form dew. If it is below freezing, then the dew will
freeze and form frost. If this happens in the air then a cloud is formed.
12. What is the relationship between dew point and relative humidity?
13. What could explain this pattern?
14. Why are clouds more likely to form high up in the atmosphere? (you’ll have to think about graph
#2 and this graph to answer this question).
Name__________________________________________________________________Period___________
Temperature, Pressure and Relative Humidity
Graphing data helps us to see patterns between different variables. Use the data from your daily
measurements and graph the air pressure on the graph below. Make sure to label the x and y axis and
give it a title.
1. Which days were stormy and which were sunny? Label on your graph above.
2. Was the pressure high or low on stormy days? What about sunny days?
3. Does rising air produce low pressure or high pressure?
4. What happens to moist air when it rises?
5. Does sinking air produce high pressure or low pressure? Does sinking air produce rain?
6. Based on this data, what factors produce stormy weather?
Use the graphs above to answer these questions:
7. How is pressure related to temperature? (as pressure rises, then temperature…)
8. How is relative humidity (R.H) related to temperature?
9. What could explain the relationship in question #8? (Hint: which can hold more water, cold air or
warm air?)
Use the graph below to answer the following
questions.
10. What happens to pressure as you go
up in elevation?
11. What happens to temperature as
pressure decreases (refer to the previous
graph if you need to)?
12. Using this information, explain why it
is colder at higher elevations, like when you
go up in the mountains?
13. How does this affect life in Utah?
14. How does this affect people who hike to the top of Mt. Everest?