Transcript NATIONAL SPATIAL REFERENCE SYSTEM

DEVELOPMENT, IMPLEMENTATION
AND FUTURE OF THE NATIONAL SPATIAL
REFERENCE SYSTEM
PROFESSIONAL LAND SURVEYORS OF OHIO
TOLEDO
FEBRUARY 11, 2000
David Doyle
National Geodetic Survey
301-713-3178
[email protected]
NATIONAL GEODETIC SURVEY
INFORMATION CENTER
(301) 713-3242
WEB SITE
http://www.ngs.noaa.gov
NATIONAL OCEAN SERVICE
INTERESTING WEB SITES
GIS/GPS/RS Web Forum
http://www.ggrweb.com/webbbs.html
The On-Line Resource for Professional
Land Surveyors
http://rpls.com
NATIONAL OCEAN SERVICE
NATIONAL SPATIAL REFERENCE SYSTEM
The National Spatial Reference System (NSRS) is that
component of the National Spatial Data Infrastructure
(NSDI) - [http://www.fgdc.gov/nsdi/nsdi.html] which contains all
geodetic control contained in the National Geodetic
Survey (NGS) Data Base. This includes: A, B, First,
Second and Third-Order horizontal and vertical
control, Geoid models such as GEOID 99, precise
GPS orbits and Continuously Operating Reference
Stations (CORS), observed by NGS as well as data
submitted by other Federal, State, and local agencies,
Academic Institutions and the private sector
NATIONAL OCEAN SERVICE
METADATA
METADATA IS DATA ABOUT DATA
DATUMS
NAD 27, NAD 83(1986), NAD83 (199X), NGVD29,NAVD88
UNITS
Meters, U.S. Survey Feet, International Feet, Chains, Rods, Pole
ACCURACY
A, B, 1st, 2nd, 3rd, 3cm, Scaled
NATIONAL OCEAN SERVICE
THE ELLIPSOID
N
b
a
S
NATIONAL OCEAN SERVICE
a = Semi major axis
b = Semi minor axis
f = a-b = Flattening
a
ELLIPSOID DEFINITIONS
BESSEL 1841
a = 6,377,397.155 m 1/f = 299.1528128
CLARKE 1866
a = 6,378,206.4 m 1/f = 294.97869821
GEODETIC REFERENCE SYSTEM 1980 - (GRS 80)
a = 6,378,137 m
1/f = 298.257222101
WORLD GEODETIC SYSTEM 1984 - (WGS 84)
a = 6,378,137 m
1/f = 298.257223563
NATIONAL OCEAN SERVICE
ELLIPSOID - GEOID RELATIONSHIP
H = Orthometric Height
h = Ellipsoidal Height
N = Geoid Height
H=h-N
H h
TOPOGRAPHIC SURFACE
N
Ellipsoid
GRS80
PERPENDICULAR
TO GEOID (PLUMBLINE)
PERPENDICULAR
TO ELLIPSOID
Geoid
GEOID99
DEFLECTION OF THE VERTICAL
DEFLEC99
THE GEOID AND TWO ELLIPSOIDS
CLARKE 1866
GRS80-WGS84
Earth Mass
Center
Approximately
236 meters
GEOID
NATIONAL OCEAN SERVICE
HORIZONTAL DATUMS
BESSEL 1841 --------------
LOCAL ASTRO DATUMS (1816-1879)
NEW ENGLAND DATUM (1879-1901)
U.S. STANDARD DATUM (1901-1913)
NORTH AMERICAN DATUM (1913-1927)
NORTH AMERICAN DATUM OF 1927
OLD HAWAIIAN DATUM
CLARKE 1866
PUERTO RICO DATUM
ST. GEORGE ISLAND - ALASKA
ST. LAWRENCE ISLAND - ALASKA
ST. PAUL ISLAND - ALASKA
AMERICAN SAMOA 1962
GUAM 1963
GRS80 ----------NATIONAL OCEAN SERVICE
NORTH AMERICAN DATUM OF 1983
(As of June 14, 1989)
STATUS OF NAD 27 AND NAD 83 STATE PLANE
COORDINATE LEGISLATION - AUGUST 1999
NO SPCS
EXISTING NAD 27
LEGISLATION
LEGISLATION
(4)
District of Columbia
Hawaii
Nebraska
Puerto Rico
I = International Feet and Meters
1 m = 3.280839895 feet
S = U.S. Survey Feet and Meters
1 m = 3.280833333 feet
ENACTED NAD 83 SPC
LEGISLATION
(3)
Alabama
Arkansas
Illinois
(45)
Alaska
Arizona (I)
California (S)
Colorado (S)
Connecticut (S)
Delaware(S)
Florida (S)
Georgia (S)
Idaho (S)
Indiana (S)
Iowa
Kansas
Kentucky (S)
Louisiana
Maine
Maryland (S)
Massachusetts (S)
Michigan (I)
Minnesota
Mississippi (S)
Missouri
Montana
Nevada
New Hampshire
New Jersey
New Mexico (S)
New York (S)
North Carolina (S)
North Dakota (I)
Ohio
Oklahoma (S)
Oregon (I)
Pennsylvania (S)
Rhode Island
South Carolina (I)
South Dakota
Tennessee (S)
Texas (S)
Utah (I)
Vermont
Virginia (S)
Washington (S)
West Virginia
Wisconsin (S)
Wyoming
GROUND LEVEL COORDINATES
“I WANT STATE PLANE COORDINATES RAISED TO
GROUND LEVEL”
GROUND LEVEL COORDINATES ARE NOT STATE
PLANE COORDINATES!!!!!
NATIONAL OCEAN SERVICE
IMPROVING POSITIONAL ACCURACY
TIME
NETWORK SPAN
NETWORK
ACCURACY
LOCAL
ACCURACY
NAD 27
1927-1986
10 Meters
First-Order (1 part in 0.1 million)
NAD 83
1986-1990
1 Meter
First-Order(1 part in 0.1 million)
HARN
1987-1997
0.1 Meter
CORS
1994 -
NATIONAL OCEAN SERVICE
B-Order(1 part in 1 million)
A-Order (1 part in 10 million)
0.02 Meter - Horizontal
0.04 Meter - Ellipsoid Height
WORLD GEODETIC SYSTEM 1984
DATUM = WGS 84(G730)
5 USAF GPS Tracking Stations
5 DMA Evaluation Stations
Datum redefined with respect to the International Terrestrial
Reference Frame of 1992 (ITRF92) +/- 20 cm in each component
(Proceedings of the ION GPS-94 pgs 285-292)
DATUM = WGS 84(G873)
5 USAF GPS Tracking Stations
7 NIMA Evaluation Stations
Datum redefined with respect to the International Terrestrial
Reference Frame of 1994 (ITRF94) +/- 10 cm in each component
(Proceedings of the ION GPS-97 pgs 841-850)
DoD World Geodetic System 1984 - Its Definition and Relationships with Local
Geodetic Systems
(also: http://164.214.2.59/GandG/pubs.html)
VERTICAL DATUMS
MEAN SEA LEVEL DATUM OF 1929
NATIONAL GEODETIC VERTICAL DATUM OF 1929
(As of July 2, 1973)
NORTH AMERICAN VERTICAL DATUM OF 1988
(As of June 24, 1993)
NATIONAL OCEAN SERVICE
GEOID MODELS
OSU 78
OSU 89B
GEOID 90
GEOID 93
GEOID 96
GEOID 99
GEOID2000???
NATIONAL OCEAN SERVICE
GEODETIC CONTROL
NETWORK OF MONUMENTED POINTS
PRECISELY MEASURED IN ACCORDANCE
WITH STANDARD PROCEDURES
MEET ACCURACY SPECIFICATIONS
ADJUSTED TO TIE TOGETHER
DOCUMENTED FOR MULTIPLE USE
NATIONAL OCEAN SERVICE
GEODETIC CONTROL DATA SHEET
1
National Geodetic Survey,
Retrieval Date = DECEMBER 20, 1999
***********************************************************************
KZ2107 CBN
- This is a Cooperative Base Network Control Station.
KZ2107 DESIGNATION - BLACK
KZ2107 PID
- KZ2107
KZ2107 STATE/COUNTY- OH/HANCOCK
KZ2107 USGS QUAD
- RAWSON (1973)
KZ2107
KZ2107
*CURRENT SURVEY CONTROL
KZ2107 ___________________________________________________________________
KZ2107* NAD 83(1995)- 40 53 34.00022(N)
083 49 24.71990(W)
ADJUSTED
KZ2107* NAVD 88
260.760 (meters)
855.51
(feet) ADJUSTED
KZ2107 ___________________________________________________________________
KZ2107 X
519,510.204 (meters)
COMP
KZ2107 Y
- -4,800,536.269 (meters)
COMP
KZ2107 Z
4,153,576.907 (meters)
COMP
KZ2107 LAPLACE CORR-0.92 (seconds)
DEFLEC99
KZ2107 ELLIP HEIGHT225.44 (meters)
GPS OBS
KZ2107 GEOID HEIGHT-35.31 (meters)
GEOID99
KZ2107 DYNAMIC HT 260.630 (meters)
855.08 (feet) COMP
KZ2107 MODELED GRAV980,118.4
(mgal)
NAVD 88
KZ2107
KZ2107 HORZ ORDER - B
KZ2107 VERT ORDER - FIRST
CLASS II
KZ2107 ELLP ORDER - FOURTH
CLASS II
GEODETIC CONTROL DATA SHEET
KZ2107:
Primary Azimuth Mark
Grid Az
KZ2107:SPC OH N
- BLACK AZ MK
357 30 36.3
KZ2107:UTM 17
- BLACK AZ MK
358 29 23.5
KZ2107
KZ2107|---------------------------------------------------------------------|
KZ2107| PID
Reference Object
Distance
Geod. Az |
KZ2107|
dddmmss.s |
KZ2107| KZ2433 BLACK RM 1
35.357 METERS 08749
|
KZ2107| KZ2434 BLACK RM 2
42.431 METERS 18658
|
KZ2107| KZ2420 BLACK AZ MK
3563826.1 |
KZ2107|---------------------------------------------------------------------|
KZ2107
KZ2107
SUPERSEDED SURVEY CONTROL
KZ2107
KZ2107 NAD 83(1986)- 40 53 34.00969(N)
083 49 24.73216(W) AD(
) 1
KZ2107 NAD 83(1986)- 40 53 34.01022(N)
083 49 24.73374(W) AD(
) 1
KZ2107 NAD 27
- 40 53 33.82300(N)
083 49 24.96100(W) AD(
) 1
KZ2107 NGVD 29
260.89
(m)
855.9
(f) LEVELING
3
KZ2107
KZ2107.Superseded values are not recommended for survey control.
KZ2107.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums.
KZ2107.See file dsdata.txt to determine how the superseded data were derived.
GEODETIC CONTROL DATA SHEET
KZ2107_MARKER: DS = TRIANGULATION STATION DISK
KZ2107_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT
KZ2107_STAMPING: BLACK 1943
KZ2107_MAGNETIC: N = NO MAGNETIC MATERIAL
KZ2107_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO
KZ2107+STABILITY: SURFACE MOTION
KZ2107_SATELLITE: THE SITE LOCATION WAS REPORTED AS SUITABLE FOR
KZ2107+SATELLITE: SATELLITE OBSERVATIONS - August 07, 1995
KZ2107 HISTORY
- Date
Condition
Recov. By
KZ2107 HISTORY
- 1943
MONUMENTED
CGS
KZ2107 HISTORY
- 1943
GOOD
CGS
KZ2107 HISTORY
- 1957
GOOD
CGS
KZ2107 HISTORY
- 1960
GOOD
CGS
KZ2107 HISTORY
- 1986
GOOD
NGS
KZ2107 HISTORY
- 19870917 GOOD
KZ2107 HISTORY
- 19891212 GOOD
OHDT
KZ2107 HISTORY
- 19900220 GOOD
KZ2107 HISTORY
- 19930712 GOOD
NGS
KZ2107 HISTORY
- 19940822 GOOD
OH-063
KZ2107 HISTORY
- 19950807 GOOD
NGS
KZ2107
STATION DESCRIPTION
KZ2107'DESCRIBED BY COAST AND GEODETIC SURVEY 1943 (APR)
KZ2107'STATION IS LOCATED ABOUT 3.9 MILES E OF BLUFFTON IN THE NE ANGLE OF
KZ2107'THE INTERSECTION OF STATE HIGHWAYS 103 AND 69. THE MARK IS SET IN THE NE
GEODETIC CONTROL DATA SHEET
KZ2107.The horizontal coordinates were established by GPS observations
KZ2107.and adjusted by the National Geodetic Survey in August 1996.
KZ2107
KZ2107.The orthometric height was determined by differential leveling
KZ2107.and adjusted by the National Geodetic Survey in January 1994.
KZ2107
KZ2107.The X, Y, and Z were computed from the position and the ellipsoidal ht.
KZ2107
KZ2107.The Laplace correction was computed from DEFLEC99 derived deflections.
KZ2107
KZ2107.The ellipsoidal height was determined by GPS observations
KZ2107.and is referenced to NAD 83.
KZ2107
KZ2107.The geoid height was determined by GEOID99.
KZ2107
KZ2107.The dynamic height is computed by dividing the NAVD 88
KZ2107.geopotential number by the normal gravity value computed on the
KZ2107.Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45
KZ2107.degrees latitude (G = 980.6199 gals.).
KZ2107
KZ2107.The modeled gravity was interpolated from observed gravity values.
KZ2107
KZ2107;
North
East
Units
Scale
Converg.
KZ2107;SPC OH N
137,000.703
488,474.571
MT 0.99994378 -0 52 10.2
KZ2107;UTM 17
- 4,530,692.991
262,138.188
MT 1.00029643 -1 50 57.4
•
Autonomous Positioning: Today
25-100 m
HORIZONTAL = 100 meters
VERTICAL = 156 meters
1996 Federal Radionavigation Plan
Section A2-1, Part B
http://www.navcen.uscg.mil/policy/frp1996
• C/A Code on L1
• Selective Availability
Standalone Positioning: By 2006
6-11 m
• C/A Code on L1
• No Selective
Availability
GLOBAL POSITIONING SYSTEM
GPS BLOCK IIF
Potential Future Developments
http://206.65.196.30/gps/issues/dotgpspressreleases.htm
30 - 32 satellites
Second and Third Civil Frequency
(1227.60 MHZ & 1176.45 MHZ)
More Robust Signal Transmissions
Real-Time Unaugmented 1 Meter Accuracy
Initial Launches ~ 2005
Complete Replacements ~ 2011
NATIONAL OCEAN SERVICE
GLOBAL NAVIGATION SATELLITE SYSTEMS
(GNSS)
POTENTIAL FUTURE DEVELOPMENTS
(2004 - 2011)
US GPS MODERNIZATION - BLOCK IIF
RUSSIAN GLONASS ENHANCEMENTS
EUROPEAN UNION - GALILEO
60+ Satellites
Second and Third Civil Frequency - GPS
No Signal Encryption - GLONASS & GALILEO
More Robust Signal Transmissions
Real-Time Unaugmented 1 Meter (or better!) Accuracy
NATIONAL OCEAN SERVICE
Standalone Positioning: By 2011
Better resistance
to interference
1-3 m
• C/A Code on L1
• C/A Code on L2
• New Code on L5
INTERNATIONAL TERRESTRIAL
REFERENCE FRAME
DEVELOPED AND MAINTAINED BY THE
INTERNATIONAL EARTH ROTATION SERVICE
PARIS, FRANCE FROM:
(http://hpiers.obspm.fr/)
VERY LONG BASELINE INTERFEROMETRY - (VLBI)
SATELLITE LASER RANGING - (SLR)
GLOBAL POSITIONING SYSTEM - (GPS)
DOPPLER ORBITOGRAPHY AND RADIO POSITIONING
INTEGRATED BY SATELLITE - (DORIS)
NATIONAL OCEAN SERVICE
INTERNATIONAL TERRESTRIAL
REFERENCE FRAME
GEOCENTRIC +/- 3 to 4 CM
MODELS FOR PLATE TECTONICS
STATION VELOCITIES
POSITIONAL STANDARD ERRORS
USUALLY BI-ANNUAL PUBLICATION
NATIONAL OCEAN SERVICE
CONVENTIONAL TERRESTRIAL SYSTEM
(CTS)
PX,Y,Z
Z CTS
Greenwich
Meridian
Earth
Mass Center
X
Y
CTS
NATIONAL OCEAN SERVICE
Equator
Z
X
YCTS
NAD 83 and ITRF
NAD 83
ITRF
Earth Mass
Center
2.2 m (3-D)
dX,dY,dZ
GEOID
NATIONAL OCEAN SERVICE
ITRF96 (Epoch 1998.0) to NAD83
ftp://ftp.ngs.noaa.gov/pub/pcsoft/htdp/
DX = 0.9910 meters
DY = -1.9072 meters
DZ = -0.5129 meters
rX = 0.02579 seconds
rY = 0.00965 seconds
rZ = 0.01166 seconds
Scale = 0.0 ppm
NATIONAL OCEAN SERVICE
ITRF94 (Epoch 1995.0) to NAD83
ftp://ftp.ngs.noaa.gov/pub/pcsoft/htdp/
DX = 0.9769 meters
DY = -1.9392 meters
DZ = -0.5461 meters
rX = 0.02640 seconds
rY = 0.01010 seconds
rZ = 0.01030 seconds
Scale = 0.0 ppm
NATIONAL OCEAN SERVICE
NAD 83 NETWORK PROBLEMS
NOT “GPSABLE”
POOR STATION ACCESSIBILITY
IRREGULARLY SPACED
POSITIONAL ACCURACY
NATIONAL OCEAN SERVICE
HIGH ACCURACY REFERENCE NETWORKS
“GPSABLE”
Clear Horizons for Satellite Signal Acquisition
EASY ACCESSIBILITY
Few Special Vehicle or Property Entrance Requirements
REGULARLY SPACED
Always within 20-100 Km
HIGH HORIZONTAL ACCURACY
NATIONAL OCEAN SERVICE
A-Order (5 mm + 1:10,000,000)
B-Order (8mm + 1:1,000,000)
FEDERAL BASE NETWORK
NGS FUNDED
NGS MARK MAINTENANCE
MAXIMUM 100 KM STATION SPACING
A and B-ORDER HORIZONTAL ACCURACY
FIRST-ORDER CLASS II ORTHOMETRIC HEIGHTS
or
SECOND-ORDER CLASS I ORTHOMETRIC HEIGHTS
SECOND-ORDER CLASS I ELLIPSOIDAL HEIGHTS
REVISIT EVERY 3 TO 5 YEARS
NATIONAL OCEAN SERVICE
COOPERATIVE BASE NETWORK
STATE/LOCAL FUNDED
STATE/LOCAL MARK MAINTENANCE
25 TO 30 KM STATION SPACING
B-ORDER HORIZONTAL ACCURACY
THIRD-ORDER CLASS I ORTHOMETRIC HEIGHTS
THIRD-ORDER CLASS I ELLIPSOIDAL HEIGHTS
REVISIT AS NECESSARY
NATIONAL OCEAN SERVICE
HIGH ACCURACY REFERENCE
NETWORKS
NATIONAL OCEAN SERVICE
USER DENSIFICATION NETWORK
FEDERAL-STATE-LOCAL FUNDING
STATION SPACING AS REQUIRED
GPS OBSERVATIONS ONLY (HORIZONTAL)
FIRST-ORDER HORIZONTAL ACCURACY
REVISIT AS NEEDED
NATIONAL OCEAN SERVICE
HARN ADJUSTMENT
A-Order Adjusted to VLBI-Existing FBN-CORS
B-Order Adjusted to A-Order
Existing Horizontal (Conventional & GPS) Readjusted
to A/B-Order
New Adjustment Date Tag e.g. NAD 83(1995)
[e.g. Michigan = NAD 83 (1994), Indiana = NAD 83 (1997)]
NATIONAL OCEAN SERVICE
HARN ADJUSTMENT
NAD 83 Data that is NOT Part of NSRS must
be readjusted by contractor/user with original observations
NATIONAL OCEAN SERVICE
NAD 83 READJUSTMENT
HARN COMPLETION - SEPTEMBER 1997
(Indiana)
GPS HEIGHT MODERNIZATION OBSERVATIONS
(1997 - 2002?)
(Ohio not yet scheduled)
(http://www.ngs.noaa.gov/initiatives/height_modernization.shtml)
COMPLETE GPS NAD 83 3-D ADJUSTMENT
(http://www.ngs.noaa.gov/initiatives/new_reference.shtml)
(2002?)
REMOVAL OF SMALL REGIONAL DISTORTIONS
(3 - 6 CM)
UNIFORM COORDINATE TAG
NAD 83 (NSRS02)
NATIONAL OCEAN SERVICE
NAD 83 READJUSTMENT
NAD 83 READJUSTMENT
ONLY GPS DATA
CONTINUOUSLY OPERATING REFERENCE STATIONS
FEDERAL BASE NETWORK
COOPERATIVE BASE NETWORK
AIRPORT SURVEYS
USER DENSIFICATION NETWORK
SPECIAL SURVEYS
NATIONAL OCEAN SERVICE
NAD 83 READJUSTMENT
WILL NOT INCLUDE OLD CONVENTIONAL
OBSERVATIONS
TRIANGULATION
TRAVERSE
TRILATERATION
INERTIAL
PHOTOGRAMMETRY
NATIONAL OCEAN SERVICE
NEW STANDARDS FOR GEODETIC CONTROL
Two accuracy standards
(http://fgdc.er.usgs.gov/standards/status/swgstat.html)
local accuracy ------------- adjacent points
network accuracy ---------- relative to CORS
Numeric quantities, units in cm (or mm)
Both are relative accuracy measures
Do not use distance dependent expression
Horizontal accuracies are radius of 2-D 95% error circle
Ellipsoidal/Orthometric heights are 1-D (linear) 95% error
NATIONAL OCEAN SERVICE
DATUM TRANSFORMATIONS
1. WHAT DATUM ARE THE EXISTING COORDINATES ON?
2. WHAT DATUM DO I WANT THE NEW COORDINATES ON?
3. HOW LARGE A GEOGRAPHICAL AREA DO I WANT TO CONVERT
AT ONE TIME?
4. HOW MANY POINTS ARE COMMON TO BOTH DATUMS?
5. WHAT IS THE DISTRIBUTION OF THE COMMON POINTS?
6. HOW ACCURATE ARE THE EXISTING COORDINATES?
0.1 Foot
1.0 Foot
10. Feet
7. HOW ACCURATE DO I WANT THE NEW COORDINATES?
NATIONAL OCEAN SERVICE
DATUM TRANSFORMATIONS
MOLODENSKY
Converts latitude, longitude and ellipsoidal height to X,Y,Z
Earth-Centered Coordinates.
Applies a 3-dimensional change in the origin (dX, dY,dZ)
Applies a change in the size and shape of the reference ellipsoid
Converts new X,Y,Z Earth-Centered Coordinates back to
latitude, longitude and ellipsoidal height
NATIONAL OCEAN SERVICE
DATUM TRANSFORMATIONS
MOLODENSKY
For continental regions accuracy can be +/- 8 to 10 meters
Does not model network distortions very well.
Assumes heights in both systems are ellipsoidal (NAD 27 did
not have ellipsoidal heights).
NATIONAL OCEAN SERVICE
DATUM TRANSFORMATION - IDEAL METHOD
•
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•
•
•
SATISFIES ALL USERS’ REQUIREMENTS
CAPABLE OF TRANSFORMING LARGE HOLDINGS OF COORDINATE
DATA
NEAR-REAL TIME APPLICATIONS
SIMPLE - METHOD SHOULD NOT REQUIRE AN EXPERT OR
DECISIONS TO BE MADE
ACCURATE
NATIONAL OCEAN SERVICE
NADCON
DESIGNED TO SATISFY THE MAJORITY OF THE “IDEAL
METHOD” DESIGN AND HAS DEFINED AS THE NATIONAL
STANDARD.
•
•
•
•
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DESIGN CRITERIA:
Relies only on NGS archived data existing in both NAD 27 and NAD 83
Provides consistent results, both forward and inverse
Fast
Not tied to NGS Data Base
Small - Fit on PC
Accurate
15 cm (1 sigma) in Conterminous U.S. NAD 27 - NAD 83(1986)
5 cm (1 sigma) per State/Region NAD 83 (1986) - HARN
NATIONAL OCEAN SERVICE
COORDINATE COMPARISON
NAD 27 to NAD 83(1986)
MOLODENSKY
(http://164.214.2.59/GandG/pubs.html)
ADJUSTED vs. TRANSFORMED
Station: BLACK
LATITUDE
LONGITUDE
40-53-34.00969 083-49-24.73216 - PUBLISHED
40-53-33.99714 083-49-24.60329 - MOLODENSKY
.01255”
.12887”
0.387 m
3.017 m
THIS CORRESPONDS TO A POSITIONAL
DIFFERENCE OF 3.042 m (9.98 ft)
COORDINATE COMPARISON
NAD 27 to NAD 83(1986)
NADCON
(ftp://ftp.ngs.noaa.gov/pub/pcsoft/nadcon/)
ADJUSTED vs. TRANSFORMED
Station: BLACK
LATITUDE
LONGITUDE
40-53-34.00969 083-49-24.73216 - PUBLISHED
40-53-34.01279 083-49-24.73591 - NADCON
.00310”
.00375”
.096 m
.130 m
THIS CORRESPONDS TO A POSITIONAL
DIFFERENCE OF 0.162 m (0.53 ft)
COORDINATE COMPARISON
NAD 83 (1986) to NAD 83(1995)
NADCON
ADJUSTED vs. TRANSFORMED
Station: BLACK
LATITUDE
LONGITUDE
40-53-34.00022 083-49-24.71990 - PUBLISHED
40-53-34.00137 083-49-24.72151 - NADCON
.00115”
.00161”
.036 m
.038 m
THIS CORRESPONDS TO A POSITIONAL
DIFFERENCE OF 0.052 m (0.17 ft)
CONTINUOUSLY OPERATING REFERENCE
STATIONS (CORS)
Installed and Operated by various Federal-State-local Agencies
CHL1 - CAPE HENLOPEN, DE
NOAA/National Geodetic Survey
NOAA/OAR Forecast Systems Lab
U.S. Coast Guard - DGPS/NDGPS
Corps of Engineers - DGPS
FAA - WAAS/LAAS (Future)
State DOTs
County and City
Academia
Private Companies
NATIONAL OCEAN SERVICE
CONTINUOUSLY OPERATING REFERENCE
STATIONS (CORS)
Variety of “Geodetic Quality” Dual-Frequency
CHL1 - CAPE HENLOPEN, DE
Antennas and Receivers
Allen-Osborne
(SNR 8000 & SNR 12 ACT)
Ashtech
(Z XII3)
Leica
(SR9500 & CRS1000)
Trimble
(4000SSE & 4000SSI)
NATIONAL OCEAN SERVICE
CONTINUOUSLY OPERATING REFERENCE
STATIONS (CORS)
Some stations provide real-time code phase observations
5 - 15 - 30” post-process carrier phase observations
Free access via Internet (RINEX-2 Format)
More than 170 Station National Network
NATIONAL OCEAN SERVICE
CONTINUOUSLY OPERATING REFERENCE
STATIONS (CORS)
NGS PROVIDES
Reference Site Survey Monumentation
Horizontal and Vertical NSRS Connections
NAD 83, ITRF94, ITRF96, ITRF97 Coordinates
Network Data Collection - Hourly & Daily
Daily 3D Network Integrity Adjustment
Public Data Distribution - Internet
(http://www.ngs.noaa.gov/CORS/cors-data.html)
2 Years On-Line Data Holding
NATIONAL OCEAN SERVICE
CORS DATA SHEET
***ITRF 96***
DETROIT 1 (DET1),
MICHIGAN
Retrieved from NGS DataBase on 09/28/98 at 08:38:44.
____________________________________________________________________________
|
|
|
Antenna Reference Point(ARP): DETROIT 1 CORS ARP
|
|
-----------------------------------------------|
|
PID = AF9501
|
|
|
|
|
| ITRF96 POSITION (EPOCH 1997.0)
|
| Computed in Mar., 1998 using 47 days of data.
|
|
X =
568024.755 m
latitude
= 42 17 50.45437 N
|
|
Y = -4690674.635 m
longitude
= 083 05 43.06542 W
|
|
Z =
4270188.820 m
ellipsoid height =
145.045 m
|
|
|
| ITRF96 VELOCITY
|
| Computed in Mar., 1998 using 47 days of data.
|
|
VX = -0.0156 m/yr
northward = -0.0035 m/yr
|
|
VY = -0.0043 m/yr
eastward = -0.0160 m/yr
|
|
VZ = -0.0026 m/yr
upward
=
0.0000 m/yr
|
|
|
CORS DATA SHEET
DETROIT 1 (DET1),
MICHIGAN
Retrieved from NGS DataBase on 09/28/98 at 08:38:44.
____________________________________________________________________________
|
|
|
Antenna Reference Point(ARP): DETROIT 1 CORS ARP
|
|
-----------------------------------------------|
|
PID = AF9501
|
|
|
|
|
|
|
| NAD_83 POSITION (EPOCH 1997.0)
|
| Transformed from ITRF94 (epoch 1996.00) position.
|
|
X =
568025.282 m
latitude
= 42 17 50.42503 N
|
|
Y = -4690676.035 m
longitude
= 083 05 43.04995 W
|
|
Z =
4270188.918 m
ellipsoid height =
146.185 m
|
|
|
| NAD_83 VELOCITY
|
| Predicted with HTDP_2.0 in Apr., 1996.
|
|
VX =
0.0000 m/yr
northward =
0.0000 m/yr
|
|
VY =
0.0000 m/yr
eastward =
0.0000 m/yr
|
|
VZ =
0.0000 m/yr
upward
=
0.0000 m/yr
|
|____________________________________________________________________________|
CONTINUOUSLY OPERATING REFERENCE
STATIONS (CORS)
GOOD COORDINATION BEGINS WITH
GOOD COORDINATES
GEOGRAPHY WITHOUT GEODESY IS A FELONY