Implementation
Guide to Studying Meteorology
Using GLOBE
Atmosphere Investigations
Does the wind shift
direction right before or after a rainstorm? Does a drop in atmospheric
pressure always indicate rain is imminent? What happens when a cold front
passes through your community? These questions and many more can be
investigated by your students using GLOBE measurements and learning activities.
By looking at their GLOBE data over time students can begin to discern patterns
in weather systems and events that will lead to an increased ability to think
and reason like a scientist. Working with data they themselves have gathered
empowers students and provides an internal motivation for students to construct
their own knowledge. GLOBE provides both the means to collect many types of
data in a systematic, scientific way and provides a series of inquiry-based learning
activities that parallel the installation of the GLOBE monitoring station.
This
Implementation Guide will offer concrete suggestions for involving middle and
high school students in data analysis and problem solving activities (DAPS),
using GLOBE data to strengthen their understanding of basic weather concepts,
within the broader context of the study of weather. The Atmosphere chapter of the GLOBE Teacher’s
Guide contains much useful information that not only is essential in helping
you set up your GLOBE study site but also will help you understand how GLOBE
can be used to study weather, climate, and atmospheric composition. The
Introduction to each GLOBE protocol contains background information on the
specific protocol and how it is related to the study of the atmosphere.
The study of
weather and climate, termed meteorology, is an integral part of Earth science.
Weather is a pervasive, important, and accessible part of our natural
environment and is of potential interest to nearly everyone. The weather seems
to be on everyone’s mind, and weather events, particularly dramatic ones
such as thunderstorms, hurricanes, and tornadoes, are intrinsically appealing
for students. Changes in our climate, such as global warming and the
possibility of another ice age, are constantly reported by the media. Yet few
people ever actually study
weather and climate or make any systematic observations of them. GLOBE offers
you and your students the opportunity to take real weather data to monitor the
atmosphere.
The Value of
First-Hand Measurements
Meteorologists
study the atmosphere by means of a number of atmospheric parameters, many of
which are part of the GLOBE measurement suite. The GLOBE Atmosphere
Investigation includes
protocols for measuring these atmospheric parameters:
q
Cloud type
and cover
q
Air
temperature (current and 24-hour maximum/minimum)
q
Precipitation
(liquid, solid, and pH of both)
q
Wind
direction
q
Relative
humidity
q
Barometric
pressure
q
Surface
ozone
q
Aerosols
GLOBE is an
excellent way for your students to be personally involved in the study of
weather. Through GLOBE they will experience observing and measuring the properties of the
atmosphere on a first-hand basis. As they employ these parameters in order to
understand the concepts and principles of weather, will use instruments to
collect, classify, and compare real scientific data. Students then deal with
the vagaries and inconsistencies of these data, determining the accuracy and
precision of their measurements.
We will separate
the weather data and atmospheric parameters into six groupings and offer
suggestions for engaging DAPS activities for your students.
The GLOBE Cloud
protocols are among the simplest to accomplish by even the youngest students
and so are a good place to start your GLOBE work. As students begin to observe
and identify clouds by type, their awareness of clouds will increase. At first,
just mastering the identifications will be challenging. To help students
improve their cloud identification skill, GLOBE provides a “GLOBE Cloud
Exploration,” including a cloud quiz in the GLOBE Resource
room.
When GLOBE
students observe and keep track of cloud types over time they can begin to see
correlations of cloud type with other aspects of the weather, such as
precipitation, air pressure, temperature, and relative humidity. Changes in
cloud type usually indicate a change in atmospheric conditions, such as the
movement into the area of a different air mass with different temperature and
water vapor content. A change in cloud type, a change in barometric pressure, a
change in wind direction and often a change in air temperature will signal the
arrival of a front, all changes that GLOBE students can observe. Students of
all ages can probably recognize some of these changes associated with cloud
type; older students can relate them to the principles of meteorology.
Clouds, composed
of droplets of liquid water, are, along with aerosols, the only part of the
atmosphere that we can see. Thus, they “stand out” from the
invisible gases that compose the bulk of the atmosphere. For students, clouds
make the atmosphere interesting and visible. When clouds drift or race across
the sky, students become aware of the atmosphere in motion. When students see
cumulus clouds swell and change their shape in just a few minutes they realize
that the atmosphere changes dynamically within just a few minutes. Middle and
secondary students can relate cloud types to atmospheric conditions more
generally, for example, noting that cumulus clouds indicate convection,
updrafts and downdrafts, and an unstable atmosphere, while stratus clouds are
the mark of a stable atmosphere.
Data Analysis and Problem Solving Activities (DAPS) for
Observing, Identifying, and Studying Clouds
1. How is cloud type related to the arrival of a cold front
or a warm front? Students use daily weather maps to determine the approximate
time and day a cold front moves through their community. Using cloud type data
for 6 cold and 6 warm front arrivals, students plot a bar graph of cloud type
frequency (general types: cirrus, cumulus, stratus) for each type of front on
the day it passes through.
* Going Further Question: Describe your cloud frequency
results using the terms rising warm and sinking cold air.
2. How do the types of clouds change before and after the
passage of a front? Using the dates obtained for the passage of 6 cold and warm
fronts, students correlate cloud types for the day before and the day after a
front passes through their community. Students construct a graph suitable to
display the data.
* Going Further Question: Why do you think the cloud types
change before and after a front passes through? Are the clouds different
depending on whether the front is warm or cold?
3. Are cloud types related to the relative humidity? Students
plot the three major types of cloud vs. the relative humidity readings for
thirty days to produce a scatter plot.
* Going Further Question: Is there a relationship between
cloud types and relative humidity? Use your scatterplot to justify your
conclusions. If you find a relationship, what might account for it?
4. Do high and low pressure systems always bring the same
kind of clouds? Students monitor weather maps to gauge when a low or high
pressure area is near their community. For daily weather maps see: http://www.nws.noaa.gov/outlook_tab.html.
Cloud type data are matched to the time when 6 low and 6 high pressure areas or
cells are nearby. Students construct a bar graph of cloud type frequency vs.
high or low system.
* Going Further Question: Is the arrival of a low or high
pressure system always attended by the same cloud type? Use your bar graph to
explain your answer.
GLOBE Resources for Observing, Identifying, and
Studying Clouds
1. Cloud Chart for Students
– See http://archive.globe.gov/sda/tg/atapp.pdf.
2. Cloud Protocols –
Good background information on clouds. See http://archive.globe.gov/sda/tg/clouds.pdf.
3. GLOBE Atmospheric
Investigation “Observing, Describing, and Identifying Clouds” at http://archive.globe.gov/sda/tg/atla-idclouds.pdf.
4. GLOBE Atmospheric
Investigation “Estimating Cloud Cover” at http://archive.globe.gov/sda/tg/atla-cloudcover.pdf.
5. For a non-graphical
treatment of DAP #4, see GLOBE Atmospheric Investigation “Cloud Watch Activity”
at GLOBE Atmospheric Investigation “Observing, Describing, and
Identifying Clouds” at http://archive.globe.gov/sda/tg/atla-cloud-watch.pdf.
The temperature
of the air is one of the most noticeable aspects of weather and climate. GLOBE
asks students to measure air temperature every day approximately 1.5 m above
the ground, in an instrument shelter, over natural cover, and away from
obstructing structures. Within one hour of solar noon they measure the current,
maximum and minimum daily temperatures.
GLOBE offers
students a chance to do more than just observe and experience the atmospheric
temperature. The fact that students measure the temperature with precise
instruments is part of what makes it a scientific study. As students keep track
of their readings at their study site, they may begin to notice patterns and
trends over weeks or months that provoke questions and lead to new investigations.
Using their own data, students apply their ideas to uncovering relationships
between other weather parameters over short time periods.
As students keep
a running record of daily, min and max temperatures, they also will observe
long-term, cyclical changes. Among the patterns in climate they may notice are
the gradual rise of temperature during spring and summer, then the gradual
decline of temperature through fall. If they keep track of day length as well,
they will note that the highest and lowest temperatures do not occur during the
longest and shortest days of the year but lag approximately a month behind the
solstices. Studying cyclical, seasonal changes in temperature can help students
understand the relationships that underlie the effect of the tilt of the Earth
on solar altitude, sunrise, sunset, and the seasons. Investigating these
relationships can lead to collaborative work with other schools, and sharing of
datasets and experimental results.
As part of
beginning to understand climate, you can use the GLOBE data to see that
seasonal patterns in temperature are different in different parts of the world.
Using the GLOBE graphing tools, students can discover that sites nearer the
equator have more nearly constant year-round temperatures and that those nearer
the poles experience greater seasonal change in temperature. Moreover, sites
near large bodies of water, such as oceans, experience more moderate seasonal
change. These patterns are opportunities to learn more about the factors that
control temperature change on a local, regional or global basis.
DAPS
Activities for Measuring and Studying Temperature
1. What is the relationship
between the altitude of the sun in the sky and the maximum daily temperature
reading? Students measure the altitude of the sun in the sky (see pg. 4 of the
GLOBE Atmospheric Investigation “Calculating Relative Airmass at http://archive.globe.gov/sda/tg/airmass.pdf)
each
hour during the school day and plot their results vs. the air temperature taken
concurrently with each altitude measurement.
*Going Further Question: Explain your
graphical results in terms of your local environmental conditions. Would your
graph look the same if you repeated your experiment six months from now?
* Going Further
Question: Analyze the following statement using your graphical results: Air
temperature rises as you go up in elevation since you are moving closer to the
sun.”
GLOBE asks
students to measure liquid precipitation, solid precipitation (snow), and the
pH of both forms of precipitation. Students can easily incorporate these
measurements into their study of weather. Understanding when and why
precipitation occurs is a central part of the study of weather and climate. The
prediction of significant precipitation, whether it is rain (squalls,
thunderstorms, and hurricanes) or snow (blizzards), is a topic of immense
interest to students, and relates to the welfare and safety of their
communities.
Just exactly
when, where, and why precipitation occurs is a complex question, but students
can begin to find patterns in their GLOBE data that will help them see that
precipitation is associated with changes in other atmospheric parameters that
they are monitoring. For example, precipitation may occur along with certain
kinds of clouds, certain air pressure changes, and certain temperature changes.
It can be an interesting investigation for students of all ages to look for
these associations.
Students also
can compare their precipitation data with data from other schools to begin to
see a larger regional pattern. The GLOBE Precipitation Protocol chapter
contains an example of such an investigation comparing a school in California
with one in Benin. See http://archive.globe.gov/sdf/tg/precip.pdf.
1. Does the
total precipitation vary month to month at your GLOBE location? Students plot
total precipitation at their location per month for a two year span.
*Going Further
Question: What are the geographical or environmental factors that cause
variations in monthly precipitation in your community and region?
2. Is the amount
of precipitation related to barometric pressure? Students plot their daily
measurements of barometric pressure vs. amount of precipitation over a period
of thirty days. All measurements taken at noon. Students plot two lines with
time (days) on the x-axis, amount of precipitation on the left-hand y-axis, and
the barometric pressure on the right-hand y-axis.
*Going Further
Question: Describe the relationship between the amount of precipitation and the
barometric pressure by comparing the two lines on your graph.
1. Precipitation
Protocols – Good background information on measuring precipitation. See http://archive.globe.gov/sda/tg/precip.pdf.
Differences in
air pressure are responsible for winds. Winds blow from areas of high pressure
to areas of low pressure. Even though GLOBE students measure air pressure at
only a single point (their study site) they can use this measurement over time
as a starting point to learn more about air pressure and its relation to wind
and weather systems.
1. Is air pressure related to the amount of
precipitation that falls? Students plot their air pressure measurements vs.
daily precipitation over a period of 60 days (time in days on the x-axis, air
pressure on the left-hand y-axis, daily precipitation on the right-hand y-axis).
* Going Further
Question: What can you conclude about the relationship between air pressure and
daily precipitation by examining the two lines on your graph?
2. Is the barometric pressure related to the relative humidity?
Students plot their measurements of barometric pressure vs. relative humidity
over a period of thirty days. All measurements taken at noon. Students plot two
lines with time on the x-axis, relative humidity on the left y-axis and the
barometric pressure on the right side y-axis.
*Going Further
Question: Describe the relationship between relative humidity and barometric
pressure by comparing the two lines on your graph.
i. Optional
Barometric Pressure Protocols – Good background information on measuring
barometric pressure. See http://archive.globe.gov/sda/tg/pressure.pdf.
Relative humidity is the percent ratio of the amount of water vapor in the air compared to the amount of water vapor in saturated air at that temperature. Relative humidity affects how moist the air feels and how comfortable the environment is for humans. Water vapor in the air affects the rate at which air changes temperature, with more humid air changing temperature more slowly. Thus, when relative humidity is high, observed minimum temperatures will be higher, other things being equal, while observed maximum temperatures will be less. The GLOBE Teacher’s Guide Relative Humidity Protocol chapter contains an example of such an investigation.
1. How is the
relative humidity related to the air temperature during the day? Students
measure the relative humidity and air temperature every hour during the school
day on three separate days. Students graph all three lines (time on the x-axis,
relative humidity on the left-hand y-axis, and temperature on the right-hand
y-axis).
*Going Further
Question: What kind of relationship exists between air temperature and relative
humidity? Compare the lines you drew on your graph. Why are they somewhat
different or why are they the same?
1. How is the dew point related to the
position of low and high pressure systems? Students draw contours on a regional
map of dewpoints on a map downloaded from http://www.weather.com/maps/currentweatherusregional.html.
If you find that they need practice drawing contours, see the Atmosphere
Investigation Activity “Making a Contour Map” at http://archive.globe.gov/sda/tg/atla-contour.pdf.
Then, students locate nearby high and low pressure systems on their regional
weather map and mark them on the dewpoint map.
*Going Further
Question: What is the relationship between the dew point and the location of a
high or low pressure system?
i. Relative
humidity Protocols – Good background information on measuring relative
humidity. See http://archive.globe.gov/sda/tg/relhum.pdf.
Becoming a
weather forecaster is a gradual process that depends on both current data and
the knowledge of how weather works. Students can begin the process by simply
observing patterns in the weather by keeping track of their observations for a
period of time. For example, because storms are usually associated with low
pressure, falling pressure may indicate a storm is coming. Rising pressure
usually indicates fair weather is on the way. Therefore, by keeping track of
pressure data, cloud observations, precipitation, temperature, and relative
humidity, students can begin to see patterns in their weather. Recognizing
these patterns will help them improve their understanding and ability to
forecast the weather.
Students can
learn much from following the movement of fronts on daily weather maps. Fronts,
either warm or cold, are relatively narrow boundary areas between warm and cold
air masses. The leading edge of an advancing cold air mass is called a
“cold front;” the leading edge of an advancing warm air mass is
called a “warm front.” The passage of a front is often associated
with a storm, which involves precipitation, change of temperature, change of air
pressure, and change of wind direction.
Using weather
maps is one way that students can learn to represent information about weather
over a geographic region. Since a weather map is a “snapshot” at a
single point in time, students can study the geographic distribution of parameters
such as temperature, rainfall, pressure, and wind speed and direction, which
meteorologists use to predict weather. The GLOBE web site allows students to
create, save, and print maps that incorporate some of the same data as
professional weather maps.
Scientists who
study the weather and climate use satellite images to aid in their
understanding and so should GLOBE students. The GLOBE web site provides direct
access to a suite of reference images that includes barometric pressure,
rainfall, cloud cover, soil moisture, soil temperature, evaporation, albedo,
vegetation index, radiation flux, and atmospheric temperature. For each of
these reference images there is a description of how the data were measured,
computed, and displayed. These, as well as other images that you may find on
the Web can help students understand larger patterns in their data and obtain
information on atmospheric parameters over wider geographic areas.
Using their
GLOBE measurements, students can collect data at their study site that will
allow them to become a local, school-based weather station. They can publish
their own weather reports and even predictions. By looking at their
accumulating data they can begin to discern patterns in their weather that will
help make their forecasts more accurate. Students can compare their
observations with those at a nearby “official” weather station and
at nearby GLOBE schools in order to see whether there are systematic or random
differences.
GLOBE students
can learn a lot by using their locally collected data to predict the weather.
In doing this, they can supplement their own data with weather maps and
satellite images. Students can use their own data in a purely empirical,
pattern-derived way to predict tomorrow’s weather. For example, given the
noontime temperature of the last several days, what noon-time temperature would
they predict for tomorrow? Finding that the accuracy of a prediction based
solely on local data is limited, they can then look at the data of other GLOBE
schools to the north, south, east, and west of them and see how these data can
be used to improve their prediction. Is there any school whose data seems to be
best at predicting their own weather? Making use of ever-widening bodies of
data, students can then look at regional and national weather maps from
newspapers and the Web and at satellite images to further refine their
predictions.
DAPS
Activities for Forecasting the Weather
1. How is
weather prediction related to the jetstream? Students plot the location of high
and low pressure systems on a national map against the position and direction
of the jetstream for seven consecutive days. On a blank national map, students
mark the location of all high and low pressure systems by consulting their
daily weather map (See http://www.nws.noaa.gov/outlook_tab.html).
Then students mark the direction and orientation of the jetstream on the same
map. (See http://wwwa.accuweather.com/adcbin/public/maps_index.asp?type=jet&getarea=us_).
Students then draw maps in a similar fashion for six additional consecutive
days.
*Going Further
Question: How important in weather prediction is knowing the path of the
jetstream?
2. How is the
strength of surface winds related to warm and cold fronts? Students overlay
national or regional weather maps with a transparency of the wind gust map for
the same day. See http://wwwa.accuweather.com/adcbin/public/maps_menu.asp
for these daily maps.
*Going Further
Question: Where do the highest wind gusts occur in relation to warm and cold
fronts? Is there always a connection between high winds and a front?
1. Atmosphere
Investigation Activity “Making a Contour Map.” See http://archive.globe.gov/sda/tg/atla-contour.pdf.
A good activity to do before students plot temperature or pressure contours on
weather maps.
• For
National and Regional weather maps of all kinds see
http://weather.unisys.com/index.html.
• National
and Regional Radar, and Infrared Satellite Maps – See http://ww2010.atmos.uiuc.edu/(Gh)/wx/surface.rxml#obs.
• For
state of the art weather graphics, current weather data of all kinds,
historical weather data for the last 10 years, state and metro radar images
updated every 5 minutes, see AccuWeather Premium Service (http://wwwa.accuweather.com/adcbin/public/promotional.asp?type=benefits=models).
This service is on a subscriber basis, 4.95 per month. In short, this site has
everything students need to begin weather analysis and prediction, using their
own data in conjunction with satellite maps and the same resources available to
professional meteorologists.