Today s topics: Elevations by GPS Datum Transformation Tool Free Learning Opportunities IMAGIN Annual Conference Traverse City, MI June 19, 2018 John Ellingson - john.ellingson@noaa.gov Great Lakes Region Geodetic Advisor (MI, IN, IL, WI)
Elevations by/from your GNSS equipment using a Geoid Model Hybrid Geoid Model a best fit model of the GEOID and NAD83 El. Ht (The NGS tool that enables you to use your GNSS equipment to determine elevations)
ELLIPSOID - GEOID RELATIONSHIP H = Orthometric Height (NAVD 88) h = Ellipsoidal Height (NAD 83 (2011)) N = Geoid Height (GEOID12B) H h N Ground Surface Geoid Geoid Ellipsoid GRS80 H ~ h N N is negative in conterminous US
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GEOID12A estimated accuracy map for MICHIGAN NOTE: GEOID12A & GEOID12B are ~equivalent in MICHIGAN
Current Web based GEOID12B tool https://www.ngs.noaa.gov/cgi-bin/geoid_stuff/geoid12b_prompt1.prl Single observation processing. Or, batch file.
NGS is replacing the current NAVD 88 hybrid geoid model NGS is working with our State partners to create one final improvement to the GEOID model for NAVD 88! It will be called GEOID18 Development is going on at this time..
LAST NAVD 88 GEOID MODEL - SCHEDULE Oct 2017 - Initial data pull, work begins Jan 2018 - Deliver prototype to Advisors for review, and dispersed to users for review Mar 2018 - Surveyors Week GPSonBM campaign Aug 2018 - Cut off for Data Submission by partners Oct 2018 Final database extraction for GEOID18 Dec 2018 Beta product release Jan-Feb 2019 Outreach at Survey Conferences Mar 2019 Integrate new model into NGS products (OPUS, Datasheets, etc).
Let s move to our 2 nd topic Transformation tools Which Horizontal Realization do you work in?
Michigan Horizontal Datums: - USSD, very old and seldom used - NAD 27 - NAD 83(1986) - NAD 83(1994)[FBN](HARN to MI users) - NAD 83(NSRS2007) - NAD 83(2011) (19 states have one more, identified as HARN in NGS tools)
NGS Transformation Tools GEOCON 2.0..then came GEOCON 5.0 Now we have: NGS COORDINATE CONVERSION AND TRANSFORMATION TOOL NCAT https://www.ngs.noaa.gov/ncat/
Remember to account for accuracy! INPUT AND OUTPUT REALIZATIONS. These are the available choices (1994) in MI NOT in MI
It started as GEOCON 2.0 ( Snapshot above is a page from the GEOCON 2.0 user s manual )
https://www.ngs.noaa.gov/ncat/
In early February, NCAT tool was moved from Beta to Production If you experience problems using this program please contact me. If you find a bug please inform me, or email NGS.Feedback@noaa.gov
Last Topic for today, NGS Learning Opportunities Monthly webinar series (plus archived presentations) Presentation Library YouTube Videos Corbin Training Center hands on classroom training
URL= www.ngs.noaa.gov
NGS Monthly Webinar Series https://www.ngs.noaa.gov/web/science_edu/webinar_series/
NGS Monthly Webinar Series Register For Upcoming Topics Download Past Presentations
NGS Monthly Webinar Series Examples of past webinars that are available for download
https://www.ngs.noaa.gov/info/subscribe.shtml
NGS Presentations Library https://www.ngs.noaa.gov/web/science_edu/presentations_library/
YouTube Videos by NGS https://www.ngs.noaa.gov/corbin/class_description/ngs_video_library.shtml
NGS CORBIN TRAINING CENTER https://www.ngs.noaa.gov/corbin/photos.shtml
Questions. My contact information: John Ellingson NGS Great Lakes Region Geodetic Advisor Cell: 202-306-6904 Email: john.ellingson@noaa.gov