Surveyor’s Corner
By Tim Burch
To the average professional surveyor, the term “geodesy” does not exist in their everyday conversations about the business. While the use of state plane coordinates has expanded greatly with the development of GPS/GNSS receivers and RTK/RTN connectivity, the mathematics and “black magic” of geodesy remains an enigma to most of the profession.
However, the ongoing progression of technology within surveying instruments has expanded the need for understanding how geodesy works. Our practitioners are faced with expanding their knowledge and expertise of geodesy and thus have put a new challenge on them to find teachers and/or mentors to provide training on the datums and techniques.
Crisis? What crisis?
Recently, I was invited to attend a geospatial workforce conference in which various government agencies, university leadership, and members of private industry gathered to discuss the future of geodesy. While the overall theme of the gathering was focused on the future of geospatial datums and how the various parties must work together, a large portion of the conversations highlighted the “geodesy crisis” we are facing throughout the surveying profession. Here are some of the points from the conference to highlight the challenges ahead:
Three levels of geodetic understanding are needed, with different but complementary approaches for each:
- Geodesy experts (geodesists) – While the overall numbers needed may be fewer than expected, we have seen a significant downturn in these experts due to attrition and lack of replacement from higher educational interest. This group includes experts who design, build, and operate our National Spatial Reference Framework (NSRS). It also includes those who utilize this framework to design and provide the multitude of tools and utilities we use every day (phone and service apps).
- Geodesy knowledgeable (professional surveyors) – This group of geodesy users is responsible for the data being utilized by the profession and follows a normal standard of care for its intended application. Professional surveyors are tasked with assuring clients and the public that the information is correct, so understanding how the tools they use work is a critical requirement. We need additional practitioners who understand the functional use of geodesy in surveying, and we need experts but are having a similar issue with attrition and recruiting.
- Geodesy cognizant (managers & technicians) – This is the area of greatest need. Our profession must have personnel who are technically capable of understanding the basics of geodesy and how it applies to the tasks within surveying. This sector, however, has the lowest cost of investment through education and training, but will continue to struggle with the same workforce recruitment faced throughout the profession.
If these employment challenges were not enough, the geospatial communities also face another potential obstacle: the upcoming modernization of the National Spatial Reference Framework (NSRS) by our colleagues at the National Geodetic Survey (NGS). Here is a brief explanation from the NGS website regarding why this modernization is a critical upgrade:
The entire geospatial economy is supported by geodesy! Credit: Dana Caccamise, NGS
The North American Datum of 1983 (NAD 83) and North American Vertical Datum of 1988 (NAVD 88), although still the official horizontal and vertical datums of the NSRS, have been identified as having shortcomings that are best addressed through defining new horizontal and vertical datums. Specifically,
- NAD 83 is misaligned to the earth’s center by about 2.2 meters, and
- NAVD 88 is both biased (by about one-half meter) and tilted (about one meter coast to coast) relative to the best global geoid models available today.
Correcting these two issues will mean that every existing latitude, longitude, ellipsoid height, and orthometric height in the United States (as reported in the current NSRS) will change by as much as four meters (as reported in the modernized NSRS). Adopting the modernized NSRS is critical, as it finally aligns the NSRS with both international standards, as well as aligning with all Global Navigation Satellite Systems (GNSS), which naturally orbit about, and provide positions relative to the center of the Earth.
There is more information about the specifics regarding the modernized NSRS on www.geodesy.noaa.gov.
As a surveyor/technician/student, what does this mean to me?
While there is an ongoing effort to address the shortage of workers in almost every profession and occupation, the “geodesy crisis,” coupled with the need for modernizing our geodetic reference frames, will take a large, profession-wide effort to tackle these challenges. Here are some of the concepts for addressing these challenges from the geodesy conference and conversations throughout the profession:
Utilize our existing resources
- Invest in our profession through education and training.
- Advocate the geodesy needs to our federal legislators (through private companies and professional organizations).
- Draw attention to upcoming advances in technology and georeference frames that an investment in geodetic infrastructure will bring us back to the forefront of mapping.
Outreach and marketing
- Expand outreach to raise public awareness of geodesy through applicable channels.
- Use examples of everyday technology and location services to highlight the importance of geodesy and its continued educational opportunities to the public.
- Create real-world examples of how geodesy impacts infrastructure, mapping, design, and informational databases of the world around us.
Collaborative efforts
- Partner government agency efforts with professional organizations to demonstrate how public/private data collection and maintenance can benefit our environment.
- Enhance relationships between government agencies, professional societies, and software providers to update critical programming to encourage use of new datums within the NSRS modernization.
Advancing educational opportunities
- Promote expansion of college programs and advanced degrees.
- Create minor degrees in geodesy or geospatial engineering to promote further studies.
- Recruit students from complementary studies, including physics, engineering, and advanced mathematics.
- Create expanded training programs and opportunities.
- Collaboration between agencies and professional societies to create specific training and certifications for geodetic practitioners.
- Encourage more “on-the-job” training opportunities within private and public employers.
The future of surveying is geospatially driven
The surveying world is simultaneously growing and shrinking due to the expanding technology and by new advances in geodetic positioning and mapping. Throughout the history of surveying, the practitioner has been tasked with measuring relative distances between fixed works and monuments. With the creation of GPS/GNSS technology (and other remote sensing technics), the surveyor has adapted to this revolution and is now tasked with the collection of locations instead of distances.
Almost all this data collection will benefit from being on a common coordinate system that aligns with the rest of the world. Geodesy is the root of this reference system, so the surveying community must make themselves more in tune with the times.
We are beginning a new chapter of not just our profession, but for mapping our world overall, and surveyors need to be at the heart of this operation. It is our duty to keep reading, learning, and progressing, so don’t close the book and dismiss the surveyor’s role in the future of geodesy. Keep reading and learning, as the road ahead will be worth it.
Tim W. Burch is executive director of the National Society of Professional Surveyors.