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US Army Corps of Engineers
BUILDING STRONG®
Sarah Falzarano, GISP
14 March 2014
Transformations between the Geodetic Datums of Hawaii Using ArcGIS
BUILDING STRONG®
Coordinate Systems
Geographic Coordinate System
Projected Coordinate System
X and Y values will vary depending on horizontal datum
BUILDING STRONG®
Geodetic Datum
The earth is not a perfect sphere►Bulge at the equator
Using a combination of an ellipsoid and geoid, a datum is born►Creates the best possible fit
• Specific to a geographic location
Used in conjunction with a coordinate system
BUILDING STRONG®
Coordinate Systems and Datums for Hawaii
Coordinate System Geographic
Hawaii State Plane
UTM
Datum WGS 1984
NAD 1983► NAD 1983 (1986)► NAD 1983 HARN (1993)► NAD 1983 PA11 (2011)
Old Hawaiian Datum
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NGS Adjusted NAD83
National Adjustment of 2011 NAD83 PA11 for the Pacific Plate
► State of Hawaii► American Samoa► Republic of the Marshall Islands
NAD83 MA11 for the Mariana Plate► Commonwealth of the Northern Mariana Islands► Guam► Palau
NAD83 2011 for North America
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CORS Stations
Use NAD83 PA11►Sometimes this is referred to as NAD83
2010.00 epoch►Many surveyors refer to NAD83 epoch 2010
• Or they may report their data simply as NAD83• If it is recent data, it is most NAD83 PA11
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BUILDING STRONG®
Datum Transformations
Designed for a particular area Have associated errors Errors compound every time a
transformation is done Consistency is key
►Use the same transformation each time
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Projecting Data in ArcGIS
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Projecting Data in ArcGIS
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Project on-the-fly
BUILDING STRONG®
Project on-the-fly
BUILDING STRONG®
Project on-the-fly
BUILDING STRONG®
Project on-the-fly
No longer recommended
No longer recommended
No longer recommended
Out
date
d D
atum
T
rans
form
atio
n R
ecom
men
datio
ns
BUILDING STRONG®
Recommended Datum TransformationsFrom To Transformation Error (m)
Old Hawaiian Datum
NAD83 (86) Old_Hawaiian_To_NAD_1983 0.20
NAD83 HARN Old_Hawaiian_To_NAD_1983_HARN_Hawaii 0.05
NAD83 PA11 Old_Hawaiian_To_WGS_1984_8 + WGS_1984_(ITRF08)_To_NAD_1983_PA11
2.10
WGS84 Old_Hawaiian_To_NAD_1983_HARN_Hawaii + WGS_1984_(ITRF00)_To_NAD_1983_HARN
0.15
NAD83 (86)
NAD83 HARN NAD_1983_To_HARN_Hawaii 0.05
NAD83 PA11 WGS_1984_(ITRF00)_to_NAD_1983 + WGS_1984_(ITRF08)_To_NAD_1983_PA11
0.15
WGS84 WGS_1984_(ITRF00)_To_NAD_1983 0.10
NAD83 HARN
NAD83 PA11 WGS_1984_(ITRF08)_To_NAD_1983_PA11 + WGS_1984_(ITRF00)_To_NAD_1983_HARN
0.15
WGS84 WGS_1984_(ITRF00)_To_NAD_1983_HARN 0.10
NAD83 PA11
WGS84 WGS_1984_(ITRF08)_To_NAD_1983_PA11 0.05
BUILDING STRONG®
ArcGIS Projection and Transformation Files Specific to Hawaii
Version 10.2.1►Includes files
Prior to version 10.2.1►Will need to copy files to your profile►Composite transformations not available prior
to 10.1►Contact myself or Craig Clouet for files and
instructions
