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Headshot: David B. Zilkoski

About David B. Zilkoski

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David B. Zilkoski has worked in the fields of geodesy and surveying for more than 40 years. He was employed by National Geodetic Survey (NGS) from 1974 to 2009. He served as NGS director from October 2005 to January 2009. During his career with NGS, he conducted applied GPS research to evaluate and develop guidelines for using new technology to generate geospatial products. Based on instrument testing, he developed and verified new specifications and procedures to estimate classically derived, as well as GPS-derived, orthometric heights.

Now retired from government service, as a consultant he provides technical guidance on GNSS surveys; computes crustal movement rates using GPS and leveling data; and leads training sessions on guidelines for estimating GPS-derived heights, procedures for performing leveling network adjustments, the use of ArcGIS for analyses of adjustment data and results, and the proper procedures to follow when estimating crustal movement rates using geodetic leveling data. Contact him at dzilkoski@gpsworld.com.

Posts by David B. Zilkoski

Scripps Institution of Oceanography establishes a geodesy program Posted on 06 Mar 2024 in the Featured Stories & Latest News & Opinions & Survey categories.

The NOAA has awarded Scripps Institution of Oceanography (SIO) and The Ohio State University (OSU) grants to develop models to address what NGS denotes as the Intra-Frame Deformation Model (IFDM). Read more»

OSU grant proposal includes developing time-dependent models for the new, modernized NSRS Posted on 07 Feb 2024 in the Featured Stories & Latest News & Mapping & Survey categories.

GPS World contributor, Dave Zilkoski, highlights the research proposal from The Ohio State University that earned them a geospatial award from the National Oceanic and Atmospheric Administration (NOAA).  Read more»

Time is running out to submit GNSS or leveling data for initial NSRS modernization Posted on 03 Jan 2024 in the Featured Stories & Latest News & Mapping & Opinions & Survey categories.

NGS has announced that users have until February 29, 2024, to submit data for the initial National Spatial Reference System (NSRS) modernization rollout. Read more»

ASPRS approves edition 2 of the ASPRS Positional Accuracy Standards for Digital Geospatial Data Posted on 06 Dec 2023 in the Featured Stories & Latest News & Mapping & Survey categories.

GPS World contributor, Dave Zilkoski, participated in the recent American Society for Photogrammetry and Remote Sensing (ASPRS) Pacific Southwest Region Fall Fechnical webinar and California Spatial Reference Center (CSRC) Coordinating Council fall meeting. Read more»

They used GPS even before it was fully built: The adoption of GPS by surveyors Posted on 04 Dec 2023 in the GNSS & Latest News & Mapping & Survey categories.

David Zilkoski discusses how NGS started performing GPS surveys in 1983, years before GPS was considered operational in 1993, changing the way NGS and others performed their surveying operations. Read more»

Federal agencies addressing the geodesy crisis Posted on 01 Nov 2023 in the Featured Stories & Latest News & Mapping & Opinions & Survey categories.

NGS awarded $4 million in grant funding to four institutions for projects that will research emerging problems in the field of geodesy, develop tools and models to advance the modernization of the National Spatial Reference System, and help address a nationwide deficiency of geodesists. Read more»

The importance of saving passive survey marks Posted on 04 Oct 2023 in the Featured Stories & Latest News & Mapping & Opinions & Survey categories.

California surveying agencies played a part in replacing and updating lost marks for the NAVD 88 project and it seems that they are doing it again. On Sept. 21, the importance of saving passive marks was discussed at the 2023 CLSA Geomatics Conference at Cal Poly Pomona/College of Engineering. Read more»

NGS’s first alpha products for the modernized NSRS Posted on 06 Sep 2023 in the Featured Stories & Latest News & Mapping & Opinions & Survey & Uncategorized categories.

GPS World contributor, David Zilkoski, explores the National Geodetic Survey's (NGS) new Alpha site, designed to enable users to preview preliminary NSRS products and services. Read more»