Environmental Data Collection Using GPS Receivers
The runoff from rain storms or precipitation events often transports pollutants from parking
lots and roof tops, and other areas to nearby streams through drains, ditches and gutters
following the hydrologic cycle (shown below).
Following a recent rain storm event, some pollution was found in a stream near your school.
The researchers and scientists need help identifying where the pollution source may have come
from, which means they’re asking you for help collecting data. As part of this, we need to know
how much rainfall came from the area and also collect the weather conditions because if it is
warm enough, some of the rainfall (or even some of the chemical pollutants) can evaporate
before migrating to streams or other waterbodies.
It is important to know where the samples are taken so that we can see what areas had the
most rainfall and identify if that is where the pollutant came from. To do this, we need to
collect the location data as well. Engineers and scientists use global positioning systems (GPS)
to find their location when doing field work. Often, this is done using handheld GPS receivers
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that use signals from satellites orbiting the earth to triangulate or close in on the location of the
device as shown below. The three satellites help identify the location of the point marked by a
large orange star. Each point on the Earth can be easily identified using a large grid or
coordinate system by its latitude and longitude. These are distances measured from the
Equator and Prime Meridian. For example, Litton Middle School is located at latitude of 36⁰13’
40” North and longitude of 86⁰43’21” West.
In this activity, your group will be responsible for collecting temperature and precipitation data
at each of the identified sites on the school grounds. This activity is intended to give you some
hands-on experience in gathering data using a hand-held GPS unit, similar to what is done by
engineers and scientists in the real world. A second portion of this assignment will involve
taking the data we have collected and importing it into mapping software called a GIS
(geographic information system).
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Assignment: Temperature, Precipitation and Location Data Collection
Your task is to measure the temperature (in ⁰F) and precipitation level (in inches) of 2 sites on
the school grounds. You will mark the point of the site on your GPS unit as a waypoint and also
record the data in your journal. You will copy the information from your journal to a colored
index card as shown below to turn in. We will then map the data using ArcGIS.com (a free
online GIS).
Creating Waypoints and Finding the Latitude and Longitude using GPS Receivers
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Turn on the GPS receiver (using the Power button on the top).
While viewing the Map screen press the MENU button.
Select Add Waypoint. (It will be numbered automatically by the GPS unit.)
Use the joystick control to move the “mouse” down to Location. Click the joystick to
select Location. Your latitude and longitude will be shown (Latitude will have a W
following it and Longitude will have a W following it.) Write this information on your
index card in the appropriate boxes.
Hit the Back key.
Use the joystick control to move the “mouse” down to the Disk/Save symbol at the
bottom of the display to SAVE the waypoint.
The waypoint is saved and you are returned to the map screen.
Repeat this for your next site.
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