The Crisis of Geodesy: A Conversation with Dave Zilkoski

1. You have an impressive career in geodesy and your contributions are numerous. Can you tell us what motivated you to study geodesy and if you had to make that decision today, would you make it the same way?

There are several things that led me to my career in geodesy.  First, my family went camping every summer when I was a kid.  I always enjoyed hiking and studying maps to understand where our campground was located relative to other nearby places, as well as to use them to explore the area.  Then, when I was in college, my curriculum included courses on surveying and geodesy.  I always loved math, but I really loved the practical uses of math.  After I graduated from college, I went to work for a surveying company.  I enjoyed the work but then I received a call asking if I was interested in working for the National Geodetic Survey (NGS).  This was in 1974 and NGS was working on the readjustments of the U.S. National Horizontal and Vertical Control networks.  Since Geodesy is the science of measuring the size and shape of the Earth, and is used to create maps, determine boundaries, and improve navigation, this was everything that I was interested in doing so I jumped at the chance to work for the agency.

Would I do it again today, absolutely.  I have been very fortunate because I had a job that I loved.  The old saying, “Find a job you love, and you will never have to work a day in your life” applies to me.  Geodesy wasn’t a job; it was my passion.  I believe the field of geodesy has more opportunities to make significant advancements in geospatial products and services working with more disciplines today than 50 years ago when I started my career.  The advancements in estimating positions based on satellite and other geospatial technology have changed how many industries do business.  Farmers use it to drive their tractors and combines, mining companies have driverless vehicles, construction companies use automated machine guidance to build roads, and, of course, it has improved how individuals navigate from one location to the next.

Thirty years ago, few farmers thought that they would be able to sit in their cab and let their combine harvester drive itself.  Geodesists, surveyors, and engineers had a vision of using GNSS to automate the use of farming and construction equipment, which became a reality.  What will it be like in another 30 years? 

Today, the company WayMo has driverless vehicles in several cities (https://waymo.com/).  The company states that Waymo is “Where Innovation Meets Responsibility.”

At Waymo, our mission is clear: be the world’s most trusted driver. We innovate beyond today’s impossible to save lives, drive inclusive mobility to offer freedom of movement for all, and improve the state of our planet and make it better than we found it.  We are building our autonomous driving technology to reinvent how people get around. Together, we are creating a world where transportation is more accessible, sustainable, safe and delightful for all. 

 I believe that in the future, it will be routine for individuals to set their cruise control for a destination and then sit back and read a book, but this will require implementing many geodetic concepts.  Positioning with GNSS and other geospatial technologies will be critical for the safety factor of driverless vehicles and the use of drones for delivery.  Geodesists, once again, will need to lead the way to meet the future positioning requirements.

2. As director of the NGS, you were responsible for carrying out many projects. Which one gave you the most satisfaction?

During my career at NGS I worked on many projects that gave me great satisfaction.  I mainly focused on adjusting and improving the height component of marks.  I was the Project Manager for the readjustment and redefinition of the North American Vertical Datum of 1988 (NAVD 88), I researched and developed guidelines for using new technology to estimate accurate heights and height differences, and I worked with the surveying and mapping community to develop guidelines for using new technology to estimate accurate ellipsoid and orthometric heights.  All these projects involved working with other Federal, State, and local agencies, and private industry. 

“That said, the satisfaction I received most from these projects was working with innovative and dedicated people that enabled the surveying and mapping community to perform their work more efficiently and effectively while maintaining accuracy standards.”

3. You have written several articles in recent years, for example in GPS World on “the crisis of geodesy”. Could you tell us what the problem or crisis is and what are the causes?

Basically, the advancements in satellites and computers have enabled geodesy to expand into many different disciplines.  Geodetic science and technology now underpin many sciences, large areas of engineering (e.g. driverless vehicles and drones), navigation, precision agriculture, smart cities, and location-based services.  Geodesy is more important than ever.

That said, geodesy has played a role in developing geospatial products, but most users do not realize that geodesy is the foundation. Since it’s been in the background, everyone assumes it will always be there. A participant at one of my workshops stated that “GPS has made geodesists out of all of us.” In my opinion, the advancements in GNSS equipment and processing software provided some users with a “false sense of knowledge or security” that they understood what was happening within the “black box.”

These statements concerned me at the time and concern me today. With the last generation of trained geodesists either retired or getting ready to retire, we are at a critical stage of not being able to meet the geospatial needs of the future. Today, The Ohio State University (OSU) Geodesy Department, where I obtained my degree, is training very few students.  As the world moves towards achieving geodetic grade positioning in real-time in support of new applications such as driverless vehicles and drones, the need for trained geodesists should be increasing not decreasing.  Universities need to educate and train the next generation of the scientific workforce of highly skilled research geodetic scientists that will expand industry’s research expertise.  The shortage of geodesists poses a significant economic risk for the USA.  There are very few geodetic science programs in the USA today, and education in geodetic proficiencies has been fragmented. 

So, what’s the cause of this decline of geodesists?  First, as I mentioned above, I attended Ohio State University (OSU) to obtain my graduate degree in Geodetic Science in 1979; therefore, I will admit that I am a little biased about the need for more geodesists — once a geodesist, always a geodesist.

In OSU’s geodesy heyday (1960–1990s), many Americans trained were sent by federal agencies: National Geospatial-Intelligence Agency (NGA), NOAA/National Geodetic Survey (NGS), USGS, Army, Navy and Air Force. During the 1970s, NGS sent two employees back to school every year. These agencies needed geodesists because they were undertaking major projects such as NGS’ to readjust the U.S. national horizontal (NAD83) and vertical geodetic (NAVD88) networks.  I was one of the employees that the NGS sent to OSU to be trained to support the NAD83 and NAVD88.

As I previously mentioned, advancements in satellites and computers have enabled geodesy to expand into many different disciplines. Today, the environment is different. U.S. federal agencies still need geodesists for developing enhanced and refined geodetic models and tools. The difference is that many people seem to believe everything has been solved in the field of geodesy because it all works so well for the average citizen and public official.

However, major U.S. companies, such as Google, FedEx, and SpaceX as well as the automobile industry, precision farming companies and mining companies also need more accurate geodetic models, tools and algorithms. Therefore, these companies need trained geodesists to perform important research on topics that address their specific geodetic requirements.  Convincing these industries how geodesists can help their industries meet the future needs of their customers is a hard sell to profit-focused companies.   

4. Is there a solution to this “problem”? Whose responsibility is it to solve it? Governments? Universities? Whose?

As indicated in the Geodesy Crisis white paper, there are significant challenges in rebuilding programs that support the training of geodesists. Today, the environment is different from when I studied geodesy in 1978.  As indicated in “the inverted geospatial pyramid” graphic, the entire $1 trillion geospatial economy is supported by geodesy. 

The number of users is increasing dramatical and they expect real-time delivery of accurate geospatial products and services.  Part of the problem is that we (geodesists) tend to talk in technical terms.  These users do not need to know the complexities of coordinate transformations, datum definitions, and development of geoid models.  They need to be explained in non-technical jargon that geodesists will enable industry, scientists, and the public to capitalize on geodetic technology and maximize its benefit. Therefore, in my opinion, it’s everyone’s responsibility to solve the problem. 

The government, universities, secondary schools, and the geospatial community all have a role to play.  Here’s a few ideas:

• Make the geospatial community aware of this crisis, that is explain in non-technical terms how geodesy provides the foundation for all geospatial products and services. Emphasizing that without maintaining and improving the foundation, everything eventually crumbles and falls apart.
• Teach rigorous math in public schools and incorporate geodesy concepts in high school’s courses.
• Strategically support and sponsor geodesy programs at universities. This support needs backing from the highest levels of the government as well as the geospatial community.
• Encourage government and industry support in the form of internships, details between agencies and industries, grants for research, professional development of staff, and research collaborations/affiliations.
• Develop programs that increase collaboration between private entitles and public agencies, focusing on providing better service that reduces costs and improves safety and welfare, and promoting awareness of the importance of geodesy to non-technical leadership.

On August 20, 2024, I had the opportunity to participate in the UN-GGIM: Europe webinar series: Quo Vadis Geodesy? webinar. The webinar highlighted the importance of geodesy and the need for more trained geodesists in Europe.  I wrote about this webinar in my September 2024 GPS World Survey Scene newsletter.   Nicholas Brown’s presentation, “You, Me and Geodesy,” provides information that others can use to explain how the global geodesy supply chain is fundamental to what they do and how critical it is to our daily lives. He describes five weaknesses that need to be addressed to improve the message of why it is important to increase the geodetic capacity in the world. I have provided a short summary below, but readers should listen to the webinar for more details.

• Evidence – There is no clear, understandable evidence to explain the importance of investing in geodesy to decision makers.
• Resources – Leadership cannot make the business case to invest in geodesy without good evidence.
• Awareness – There is a need to communicate the importance of geodesy to other science agencies and scientists in different fields of study. For example, climate change is highly dependent on geodesy for measuring sea level rise, changes in gravity, ice melt, and the location of Earth’s center of mass.
• Capacity – Capacity development in geodetic science needs to be strengthened everywhere not just in developing countries.
• Governance – The scientific geodetic community has done an exceptional job of managing the geodetic infrastructure (e.g., International Association of Geodesy) but they are expected to do too much. During Nicholas Brown’s presentation, he mentioned that, in his opinion, an improved governance model could help advance geodesy around the world. He mentioned the need to have a governance model like the World Meteorological Organization(WMO). WMO members contribute resources to the organization, technical commissions are established to address issues, and operational support and resources are provided to implement capacity development programs.

5. In Latin American countries there are several university centers of excellence for the training of geodesists, however few students decide to pursue these studies and the few who do so find it difficult to find jobs. Have developed countries such as the United States or Europe looked at Central and South American countries where there is human potential for this science and engineering?

In the United States, it is difficult for Federal agencies to hire non-U.S. citizens.  This is true for most U.S. Federal agencies, and many companies that do contractual work for federal agencies.  That said, I believe there could be opportunities for individuals, especially with major industries such as Google, FedEx, automobile industry, UAV companies, precision farming companies, and mining companies.  For example, many companies make unmanned aerial vehicles (UAVs), including Skydio, AeroVironment, Parrot, ABJ Drones, Autel Robotics, DJI, Freefly Systems, Lockheed Martin, and Northrop Grumman.  These companies could benefit from the expertise of a geodesist.  The slide From Yehuda Bock Ph.D.’s presentation to the American Association for Geodetic Surveying (AAGS) General Membership Meeting highlights the many disciplines that rely on geodesy.

“I would encourage these university centers of excellence that train geodesists to reach out to these industries and others to explain that geodesy is the foundation for their products and services and that there is a possibility that this foundation may go away without action.”

6. You co-authored with other leading geodesists the report published in January 2022, titled “The Crisis of Geodesy,” which documented concerns about the lack of trained geodesists in the United States and presented the surprising state of geodesy in China. Is anything being done in the rest of the world to bridge this gap, or will it continue to widen?

As I previously mentioned, the UN-GGIM: Europe webinar series: Quo Vadis Geodesy? webinar highlighted the importance of geodesy and the need for more trained geodesists in Europe.  Based on the presentation by Ramon Hanssen it appears that the lack of trained geodesists is also a concern of the European geospatial community.  During the webinar, Ramon Hanssen and Peter Teunissen, TU Delft, described a way forward for Europe. The presentation described “The IDEA League,” which is a strategic alliance between five European universities of technology: TU Delft, ETH Zurich, RWTH Aachen, Chalmers University, and Politecnico di Milano. One goal of the partnership is to re-establish Europe as a technological and scientific leader by integrating academic resources and knowledge.

The alliance established an initiation team to develop a proposal that included the following:

• Establish a joint international European MSc program in Geodesy.
• Combine resources of universities, scientists, and educators in Europe.
• Respond to the urgent need for academic geodesists.
• Inspire collaboration via complementary fields.

What I found very interesting is that the group sent a questionnaire to stakeholders in the geodetic job market to obtain an understanding of the need for trained geodesists. The responses to the questionnaire highlighted the urgent need for more trained geodesists. Two important responses from stakeholders were the following:

1. 72% perceived the current availability of MSc graduates in geodesy to be unsatisfactory and
2. 83% expects the demand for (academic) professionals with expertise in geodesy to grow in the foreseeable future.

The webinar was recorded and can be found here. The presentations can be downloaded from the following weblinks:

• You, Me and Geodesy– Nicholas Brown, UN-GGCE
• International MSc Geodesy– Ramon Hanssen and Peter Teunissen, TU Delft

7. Can you send a message to professionals, teachers and students of geodesy in Latin America about their role in this crisis and its solution?

I mentioned in question 4 – Is there a solution to this “problem”? that universities, secondary schools, and professionals in the geospatial community all have a role to play.  I provided a few suggestions when addressing that question but my December 2022 GPS World Survey Scene newsletter provided some examples and websites for discussing geodesy with students as well as non-geodetic professionals.  Here’s a few examples:

• Professionals, teachers and students can work with high school math students to explain how geodesy is the foundation of many of their phone apps such as “How does my phone know where I am?” and “Have you ever wondered how your phone appears to know where you are on a digital map while you’re walking or driving down the street?”
  • The govwebsite has lessons describing GPS that are designed for kids. One lesson introduces the concept of GPS trilateration. The lesson explains how GPS positioning works on two basic mathematical concepts:

1. Trilateration, which literally means positioning from three distances, and
2. The relationship between distance traveled, rate (speed) of travel, and amount of time spent traveling.

This was developed by NGS for a National Science Teachers Association Conference. You can download both the instructions and map.’

                                                                                   GPS Trilateration Lesson

 

• There are free online lessons and tutorials that describe the concepts associated with geodesy. Some of the online videos are at a level for young audiences, and some are aimed at individuals with more advanced education. Most of them describe the concepts using diagrams with narratives, and without complex math equations. NGS provides a number of videos that can be downloaded here.

• UNAVCO, a non-profit university-governed consortium, facilitates geoscience research and education using geodesy. UNAVCO has a video that describes the tectonic plates and how geodesists measure their movements. Another UNAVCO video describes what geodesy is, as well as geodesy’s application in our everyday lives (UNAVCO’s 2017 USIP geoscience video production). Visit UNAVCO’s website to learn more about its mission.

• This link(https://gisgeography.com/geodesy/) provides a tutorial on “Why is geodesy the framework behind all mapping and navigation?” The article states. “If you think about it, the whole field of geomatics lies on the shoulders of geodesists. Because it’s really geodesy that is the framework behind all surveying, mapping and navigation.”

                                                                                           What Is Geodesy?