Google Earth:Poor Man’s GIS, Fabulous Tool!

Where to Get Help and Info

Google Earth User Guide: http://earth.google.com/userguide/v4/

Google Earth Help Group: http://groups.google.com/group/earth-help/

Google Earth blog: http://www.gearthblog.com/

The Basics

Finding locationsUsing layersAdding locations and layersNavigatingGetting coordinates

Opening ViewSearching for locations

Search for Location

Works like in Google Maps: Named location or Address or Latitude and longitude

Zoom or “fly” to location by double-clickingSave desired locations to “My Places”

Opening View

Saved locations

Saved LocationsSame as any other file management:

Drag-and-drop Create folders to organize site information Give meaningful names

Anything under “My Places” will be savedAnything under “Temporary Places” is

gone after you shut Google Earth

Opening View

Ready-Made Layers

Ready-Made Layers

Lots of pre-compiled informationCan make it really slow to loadCan make it confusing to navigate

Unselect most or all to navigateSelect only the ones you need, once you’re

close to your location

Some Useful LayersGeographic Web:RoadsBorders and LabelsTerrain (3D effect)

EarthquakesVolcanoesParksHospitalsSchools

And as usual: Garbage in, garbage out

(i.e., the databases are not 100% accurate)

Getting More Layers National Wetlands Inventory: http://

www.fws.gov/nwi/WetlandsData/GoogleEarth.htm USGS Earthquake Hazard Program: http://

earthquake.usgs.gov/research/data/google_earth.php Humboldt Bay Trail network:

http://www.green-wheels.org/node/313 Google Earth Gallery:

http://www.google.com/ig/directory?synd=earth

Navigation - 1Mouse left-click lets you pan: drag or spin the

globe while your point-of-view remains fixedMouse right-click lets you fly: move your

point-of-view up, down, and around a fixed location target

Scroll wheel lets you zoom straight in and out vertically

Navigating - 2Sliders let you pan and fly as wellDouble-click “North” to reset orientationVertical slider tilts the point-of-viewArrows pan north, south, east, westNumbers pad: + and – let you zoom

straight in and out vertically

Getting Coordinates

For the new project initiation procedure, we’ll need project coordinates. Navigate to the project site Place your mouse cursor over the location Read the latitude and longitude off the bottom

status bar

Mouse cursor

Coordinates

Fun Stuff

Inserting placemarksInserting polygons and pathsMeasuring distances

Placing and Moving Points

Use different markersAdd labels and coloursRight-click to editPossible project uses:

Points of interest (e.g., water tank, hospital) Sampling locations

Add Placemark tool button

Marker style

Add label and description

Proposed monitoring wells

Creating Polygons and PathsPolygon: Closed shape, filled or outlined

e.g., Site boundary, building footprintPath: Curved line, open shape

e.g., Road, trail, fault line, groundwater levelsBoth can be drawn point-to-point or

freehand (create lots of points)Can edit, delete, add or move points

Measuring DistancesLine (btwn two points) or Path (multipoint)Choose units: feet, yards, miles, etc.Move the nodes to desired locationsFollows surface (“walked” distance)Check “Mouse Navigation” to move

around, then uncheck to continue measuring

The Really Cool Stuff

Importing maps, site plans, and aerial photos

Sharing files and collaboratingSaving images

Overlays 1: Inserting a MapThis is what you use when your map has

latitude and longitudeMap needs to be in a recognized format,

such as PNG, GIF, JPEG, BMP, or TIFFMap needs to be in cylindrical projection

(or small enough to be close)Memory hog: keep your images small

(<2000 x 2000 pixels)

Inserting a Map (Cont.)

Find the map then convert it to the right format

Navigate to known latitude and longitude

Importing a Map (Cont.)Show grid (under View drop-down menu)Google Earth automatically re-projects

cylindrical projectionLine up the map’s longitude and latitude

using the handlesSlide image transparency to make it easier

to align

Overlays 2: Inserting a Site Plan

More fiddly, inexact, but useful!Same file formatsMay need to capture a PDF or ACAD file

and save it to a usable formatInclude some reference points to line up

with the terrain

Site layout from ACAD file

Inserting an Air Photo

Patching up the record with better or more recent air photos

Photos need to be ortho-rectifiedWorks the same as inserting a site plan

Air photo to fill obscured area

Google Earth jazz

Adding it all together, e.g.: Draped maps over contours Site map plus sampling locations plus wetland

polygons Project footprint plus fault lines

Support project decisions

Geology draped over terrain

Wetlands and wells

Sharing Google Earth FilesKeep your files organizedSave the folder containing files to share:

Points, polygons, paths, map overlays, photosSaved as a single .KMZ file, can be kept in

the project folderSaves small, easy to e-mailOther people can edit and re-save

Saving as JPEG

Allows you to save screen content as just an image (can’t edit points in Google Earth)