California Spatial Reference Center (CSRC) 2023 Spring Meeting

June 7, 2023 - By David B. Zilkoski

On April 27, I attended (virtually) the spring 2023 meeting of the California Spatial Reference Center (CSRC) coordinating council. See the agenda below. This column will highlight some activities with which the CSRS is involved and how it’s advancing the science of geodesy. Anyone who has been following my latest columns knows that I am an advocate for any person or organization that promotes the advancement of geodesy and recognizes that the United States is experiencing a geodetic crisis.

First, I would like to state that Yehuda Bock, the director of CSRS, has been instrumental in advancing accurate geodetic positioning for as long as I have known him. I first met Bock in 1978 while I was attending the Ohio State University.

A video of the meeting is available from the CSRC here.

During the meeting, Bock presented the director’s report. He started with mentioning how geodetic infrastructure and methodologies are essential to mitigating the effects of natural hazards. That is something that affects everyone in the world, especially California, and one of the reasons that I always end my email messages and presentations with the following statement: “Geodesy is the foundation for all geospatial products and services.”

Geodetic infrastructure and methodologies. (Image: Yehuda Bock, Scripps Institution of Oceanography)

Bock highlighted how GNSS is important to explaining natural phenomena and hazards of the Earth. Most individuals use GNSS to know where they are on a map on a phone, but GNSS (and geodesy) is so much more important to the average citizen than just knowing their location on Earth. As you can see from the image below, GNSS positioning provides information about many of Earth’s systems, such as changes in local mean sea level, the values of atmospheric parameters, the status of water resources, and the movement of the Earth’s surface due to tectonic plates, glaciers, earthquakes and volcanoes. One or more of these activities are important to every individual in the world.

(Image: Yehuda Bock, Scripps Institution of Oceanography)

Bock provided examples of how GNSS has been used to investigate and monitor earthquakes, which is extremely important in California. See the image below.

Displacement due to earthquakes. (Image: Yehuda Bock, Scripps Institution of Oceanography)

He highlighted a methodology of a kinematic datum that uses an intra-frame velocity model to estimate positions at any location and at anytime with respect to a reference frame and epoch. This concept is part of the National Geodetic Survey’s new, modernized, National Spatial Reference System (NSRS). Several of my previous columns have discussed NGS’ NSRS and time-dependent coordinates (for example, see my August 2022 column).

(Image: Yehuda Bock, Scripps Institution of Oceanography)

California’s geodetic network is significantly affected by crustal movement. To help address this issue, the CSRS updated the NAD 83 coordinates. It’s denoted as CSRS epoch 2017.5 (NAD 83). See the image below for the project report on the update. This is important to anyone surveying in California because of the crustal movement affecting the coordinates of the monuments. California is well positioned to implement NGS’ NSRS. Part of the implementation of the CSRC epoch 2017.50 (NAD 83) was to have the new epoch-date coordinates transmitted with RTCM 3.0 data streams. This is something that other RTN operators from around the nation will have to do after NGS publishes the NSRS coordinates. The CSRS is a model from which others can learn.

Excerpt from CSRC epoch 2017.5 project report. (Image: http://sopac-csrc.ucsd.edu/index.php/epoch2017/)

Users that access CSRC’s epoch 2017.50 website, can find the coordinates of marks published in CSRC epoch 2017.50 (NAD83). See the image below for an example.

Mark p530 in CSRC epoch 2017.50 (NAD83). (Image: CSRC Website)

Bock discussed the integration of InSAR and GNSS to estimate accurate land changes over large areal extents. This type of research can help in developing an accurate intra–frame deformation model (IFDM) to account for movement between survey epoch coordinates (SEC) and reference epoch coordinates (REC). See my August 2022 column for more on NGS’s definition of SEC and REC coordinates.

(Image: Yehuda Bock, Scripps Institution of Oceanography)

The rest of the director’s report included the following topics:

reference surfaces for unified reference frame
observation systems: terrestrial and marine geoids
unified reference frame
GNSS-IR
airborne gravity
geoid model
machine l;earning
tracking atmospheric rivers with GNSS meteorology
tracking extreme weather events with GNSS meteorology
cluster analysis to unsupervised analysis of GNSS time series isolate geophysical effects
proposed geodesy curriculum at SIO.

The last one was the most important one to me because developing educational curriculums that include geodetic topics will help advance the science of geodesy.

(Image: Yehuda Bock, Scripps Institution of Oceanography)

Other speakers at the coordinating council meeting discussed the use of geodetic science in projects such as measuring sea level rise along the California coast as well as performing geodesy on the seafloor.

There was an interesting presentation by Humberto Gallegos discussing how to fill the skill gaps through the Geo-Spatial Engineering and Technologies (GSET) program at East Los Angeles College (ELAC). This program is helpful in developing future surveyors and geodesists.

(Image: EarthScope)

There also was a presentation on EarthScope by Bill Funderburk. See below for a few slides from Bill’s presentation. The presentation discussed the update on the Network of the Americas (NOTA). Bill provided information on NOTA partners, NOTA network and data, NOTA in California, and the EarthScope merger. His presentation also highlighted the many partners that support the NOTA, which includes 1,147 GPS/GNSS stations across the United States, Mexico and the Caribbean. Many individuals may not know it, but UNAVCO and IRIS merged on January 1, to become the EarthScope Consortium. Readers can find more information on this new organization here.

(Image: EarthScope)

I only highlighted a few items from the meeting. Please see the video of the meeting for more details.

During the meeting, Bock was also presented with the CSRC Founders Award. It was a great honor for me to say a few words recognizing the important contributions that Bock has made to the geodetic community over the past five decades. It is in large part due to his leadership that California has progressed so much in geospatial positioning services. The following are a few photos from the ceremony and a statement from the CSRS.

Recognition Statement from the California Spatial Reference Center

“Distinguished Research Scientist, Yehuda Bock, was recognized by the California Spatial Reference Center (CSRC: http://sopac-csrc.ucsd.edu/index.php/csrc/) with the Founders Day Award. Presented by Dana Caccamise, Bock was honored for the “thriving science and community outreach facilitated through [his] vision and implementation of the Center for decades.” With Bock’s guidance, CSRC was established in 1997 as a partnership with surveyors, engineers, GIS professionals, the National Geodetic Survey (NGS), the California Department of Transportation (Caltrans), and the geodetic and geophysical communities, and has become of IGPP’s most successful outreach efforts.”

From left to right: Gregory Helmer, Sharona Benami, Yehuda Bock, Dana J Caccamise II (Image: Karissa Duran, Scripps Institution of Oceanography)

The dedicated plaque and monument. (Image: Karissa Duran, Scripps Institution of Oceanography)

In my opinion, integrated and collaborative organizations are necessary for the successful development of geospatial products and services.

I would like to highlight how the Ohio State University is integrating geodesy in a geology program. The Ohio State University Geology Field Camp is a geology class that is held every year. This year, the OSU Geodetic Department is going to participate in the program to explain how the science of geodesy is helpful to geologists. The plan is to provide exercises to explain how the camp’s activities can be enhanced with geodetic techniques.

The 2023 geology summer field course lasts six weeks. This year, the course starts on Thursday, June 1, and ends on Friday, July 14. Students receive six semester credit hours for completion of the course.

The course emphasize the following:

observation of stratigraphic units and their characteristics
interpretation and synthesis of structures, paleoenvironments, and geologic history
presentation of results by means of geologic maps and cross-sections
experience with 3D visualization, GIS, GPS and computer analysis of field data

In conclusion, on June 22, NGS is hosting a webinar that will discuss some of the benefits and challenges of transitioning to the modernized NSRS. The presenters are not NGS employees. They are guest speakers from the geospatial community. I would encourage all users to register for this webinar.