Now & the Future of Geodesy in Hawaii for the GIS Users

Edward E. CarlsonPacific Region Geodetic Advisor

NOAA’s National Geodetic Survey

http://www.bing.com/videos/search?q=Geodesy%20youtube&FORM=O1HV1

What is geodesy?Geodesy is the science of measuring

and monitoring the size and shape of

the Earth.

The Earth is an irregular surface, difficult

to model.

Accurate positions are required for a wide

variety of applications.(e.g. monitoring climate change impacts and sea level change)

Why is geodesy important?

Geodetic control (NSRS) is the foundation for all geospatial products.

Without a geodetic control “base map” layer, GIS applications will not work properly!

Accurate positions beginwith accurate coordinates!

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TIME NETWORK LOCAL NETWORK SPAN ACCURACY ACCURACY

Old Hawaiian Datum/ 1927-1986 10 Meters First-Order (1 part in 0.1 million)

NAD 27 NAD 83(1986) 1986-1993 1 Meter First-Order(1 part in 0.1 million)

NAD83(1993) 1987-1997 0.1 Meter B-Order(1 part in 1 million) HARN A-Order (1 part in 10 million)

NAD83(PACP00) 1994 - 2111 0.02 Meter - Horizontal CORS 0.04 Meter - Ellipsoid Height

NAD83(2011,PA11,MA11) 2111 - 0.01 Meter - Horizontal CORS 0.02 Meter - Ellipsoid Height

National Spatial Reference System(NSRS) Improvements

Hawaiian Islands

445.518 m

451.588 m451.359 m

461.047 m

Datum Differences

OLD HAWAIIAN DATUM to NAD83(1986)

Hawaiian Islands

0.885 m

1.38 m1.57 m

1.31 m

Datum Differences

NAD83 (1986) to NAD83 (1993) / HARN

NAD 83(2011) epoch 2010.00• Multi-Year CORS Solution (MYCS)

– Reprocessed all CORS GPS data Jan 1994-Apr 2011– 2264 CORS & global stations– NAD 83 computed by transformation from IGS08

• National Adjustment of 2011 (NA2011)– New adjustment of GNSS passive control– GNSS vectors tied (and constrained) to CORS

NAD 83(2011) epoch 2010.00– Approximately 80,000 stations and

400,000 GNSS vectors• Realization SAME for CORS

and passive marks• This is NOT a new datum! (still NAD 83)

7/13/2014 92014 Esri AEC Summit

CONUS CONUS

AlaskaAlaska

Pacific Pacific (MA11)(MA11)

Pacific (PA11)Pacific (PA11)

Median accuracy (95% conf.):0.9 cm horiz, 1.5 cm height

Hawaiian Islands

NAD83(PACP00) – NAD83(PA11) = 0.02mNAD83(PA11) - WGS84(ISG08) = 2.42mNAD83(PACP00) – WGS84(ITRF00) = 1.80m

NAD83(PACP00) – NAD83(PA11) = 0.02mNAD83(PA11) - WGS84(ISG08) = 2.44mNAD83(PACP00) – WGS84(ITRF00) = 1.87m

NAD83(PACP00) – NAD83(PA11) = 0.02mNAD83(PA11) - WGS84(ISG08) = 2.45mNAD83(PACP00) – WGS84(ITRF00) = 1.88m

NAD83(PACP00) – NAD83(PA11) = 0.02mNAD83(PA11) - WGS84(ISG08) = 2.47mNAD83(PACP00) – WGS84(ITRF00) = 1.91m

NGA did a new definition of WGS84 in 2012aligned with - IGS08 epoch 2005.0

Datum Differences

NAD83(MARP00) – NAD83(MA11) = 0.08mNAD83(MA11) - WGS84(ISG08) = 1.13mNAD83(MARP00) – WGS84(ITRF00) = 1.05m

NAD83(PACP00) – NAD83(PA11) = 0.16mNAD83(PA11) - WGS84(ISG08) = 3.05mNAD83(PACP00) – WGS84(ITRF00) = 2.45m

NAD83(MARP00) – NAD83(MA11) = 0.03mNAD83(MA11) - WGS84(ISG08) = 1.23mNAD83(MARP00) – WGS84(ITRF00) = 1.15m

Datum Differences

The National Geodetic Survey Ten-Year PlanSupport the users of the National Spatial Reference System.

Modernize and improve the National Spatial Reference System.

Expand the National Spatial Reference System stakeholder base through partnerships, education, and outreach.

Develop and enable a workforce with a supportive environment.

Improve organizational and administrative functionality.

http://www.geodesy.noaa.gov/web/news/Ten_Year_Plan_2013-2023.pdf

Both a new geometric and a new geopotential (vertical) datum will be released in 2022.

The realization of the new datums will be through GNSS receivers.

NGS will provide the tools to easily transform between the new and old datums.

Modernizing the NSRSPositioning America in a dynamically changing world

How will the new datums affect you?

The new geometric datum will change latitude, longitude,

and ellipsoid height by between

1 and 2 meters.

The new vertical (geopotential)

datum will change heights on

average 50 cm (20''), with

a 1-meter (39'') tilt towards

the Pacific Northwest.

NAD 83(2011) to NAD 83(2011) to IGS08 at epoch 2022.0IGS08 at epoch 2022.0

NAD 83(PA11) to NAD 83(PA11) to IGS08 at epoch 2022.0IGS08 at epoch 2022.0

NAD 83(2011) to NAD 83(2011) to IGS08 at epoch 2022.0IGS08 at epoch 2022.0

Changes between in New Datum• NSRS coordinates change?

– North America plate (CONUS and AK): Approx 0.8 to 1.6 m

– Pacific plate: Approx 3.4 (Midway) to 4.3 m (American Samoa)

– Mariana plate: Approx 1.1 to 1.4 m

• NSRS ellipsoid height change?– Approx -1.9 m (Puerto Rico) to +2.0 m (Guam)

Hawaii

Alaska “CONUS”

Puerto Rico / Virgin Islands

Guam / Northern Marianas

American Samoa

Planned GRAV-D Coverage

What to do now!!! Move to newest realizations.

NAD 83(2011,PA11,MA11) epoch 2010.00USGG12 (gravimetric geoid) / GEOID12A

Require/provide complete metadata for all mapping contracts.How did they get the positions/heights? Document it!

Obtain precise ellipsoid heights on bench marks. (OPUS-DB, contact NGS Geodetic Advisor)Improves hybrid geoid models and provides “hard points” in new vertical datum.Follow new NGS Guidelines when released.

Move away from passive marks to GNSS.Especially, move away from classical passive control.

Move from NGVD 29 to NAVD 88. (For CONUS only)Understand the accuracy of VERTCON in your area.

Does this stuff really matter?• Significant for accuracies better than ~1-2 m

– Can be problem for combining accurate datasets– Requires understanding of modern datums– Be careful when using “WGS 84”

• Which realization? At what epoch? At what level of accuracy?

• Things are moving, and it can make a difference– e.g., San Diego moving 4.0 cm/yr NW w.r.t. Phoenix, AZ

• GNSS becoming more precise– Autonomous positions soon better than 1-2 m– But accuracy another issue… with respect to what?

www.ngs.noaa.gov

Educational Videoshttp://www.ngs.noaa.gov/corbin/class_description/NGS_Video_Library.shtml

NGS has partnered with The COMET Program to develop educational videos.

View videos on COMET YouTube channel: https://www.youtube.com/playlist?list=PLsyDl_aqUTdGmAeHGgFucHkTfWDOwElOB

NGS Monthly Webinar Serieshttp://www.ngs.noaa.gov/web/science_edu/webinar_series/

Presentations related to NGS programs, projects, products and services.

Second Thursday of every month, 2:00-3:00 p.m. East Coast time.

Webinar series Web-pages:view previously recorded webinars,register for upcoming webinars, andsubscribe for monthly notifications.

Contact: NGS.Webinar@noaa.gov

NGS TOOL KIT

Questions ????

Edward E. CarlsonNational Geodetic Survey

808-725-5255ed.carlson@noaa.gov