GPS Measurement Protocol

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GPS Measurement Protocol
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Goals for the Training Session

• Provide an inquiry context for the data
  collection and science content
• Provide accurate science content
• Review procedures for data collection
• Review data entry and analysis
• Discuss classroom implementation ideas
• Collect feedback from participants

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Inquiry Context

• Are there patterns visible in the mapped data?
• What Earth system factors may explain differences
  in data from the same latitude around the globe?

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Local Inquiry Example
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Why do GLOBE scientists use GPS?

• Locates your school GLOBE study sites
• Provides accurate geographic coordinates for
  GLOBE data allowing others to analyze the data
  from a spatial perspective
• The locations are in a form that is easily used
  by anyone around the world

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Science Content Global Positioning System (GPS)
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Science Content Latitude Longitude
1 degree of longitude 0 km
1 degree of latitude 111 km
Magnetic Declination
1 degree of longitude 111 km
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Science Content Elevation
GPS elevation measures in reference to the
Ellipsoid.
Topographic elevation is measured in reference to
the Geoid.
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Instruments GPS Receiver Magnetic Compass
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The Measurements

• GPS Measurement
• Latitude
• Longitude
• Elevation
• Offset GPS (only as needed)
• True North
• Corrected Latitude
• Longitude
• Elevation

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Collecting Data Field/Lab Guides Data Sheets

• Field/Lab Guides
• GPS Protocol Field Guide
• Offset GPS Protocol Field Guide
• Data Sheets
• GPS Investigation Site Location Data Sheet
• GPS Investigation Data Sheet
• Offset GPS Measurements Data Work Sheet

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Collecting Data ProtocolGPS Measurement

• Hold vertically away from body
• Wait until you acquire at least four satellites
• At one minute intervals record 5 measurements
• Latitude
• Longitude
• Elevation
• Time
• Number of satellites
• 2D or 3D
• Average measurements

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Collecting Data ProtocolOffset GPS

• Determine True North
• Move either north of south from Study Site until
  GPS reception is good
• Measure distance from Study Site
• Divide by (11 meters/.0001 degrees) to get
  latitude correction
• In the northern hemisphere, add (if you took
  reading south of study site) or subtract (if you
  took reading to the north of study site) latitude
  correction
• Record corrected GPS measurement

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Enter Data on the GLOBE Web Site
Step 1 Select Define, Edit, or Update a Site
from the site definition data entry menu Step 2
Select the site you wish to enter GPS data
for Step 3 Enter GPS data for the observation or
measurement sites needed Step 4 Confirm data
entries on verification page
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Looking at the Data
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Classroom Implementation

• Inquiry
• Curriculum/Standards Alignment
• Assessment
• Classroom Management

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Getting Started

• The GLOBE Web site has information
• http//www.globe.gov
• GLOBE Help Desk or your Country Coordinator can
  support you as you get started.
• Get your students involved doing real science!