Geodesist Gary Johnston on where maths and Earth meet

Gary Johnston on top of the world after winning a Queen’s Birthday Public Service Award in 2018. Image: ©AuScope.

Gary Johnston on top of the world after winning a Queen’s Birthday Public Service Award in 2018. Image: ©AuScope.

Recently, long-term AuScope collaborator, Gary Johnston of Geoscience Australia won a Queen’s Birthday award for outstanding public service in national and international satellite positioning and geodesy.

We uncover this humble scientist’s passion for geodesy (where maths meets Earth), journey with AuScope from the start, and sizeable feats for positioning in Australia.

How did you become interested in Earth Science?

I grew up in a farming community in bushy Brogo, NSW and loved life in the great outdoors. At school, I discovered that I was good at mathematics and then became interested in surveying.

I studied at the University of Canberra and found work as a graduate with the Australian Surveying and Land Information Group (AUSLIG, now Geoscience Australia, GA) in Darwin. There I was involved in large-scale boundary surveys for Aboriginal land claims, and was struck by geodesy– the branch of mathematics which deals with the shape and measurements of the earth, or large portions of it.

In 1993, I transferred back to Canberra to work on the geocentric datum of Australia (GDA94)– 
my introduction to the Global Positioning System (GPS) and geodesy, at the University of Canberra. Soon after I joined GA’s geodesy program. I went on to work in Global Navigation Satellite System (GNSS) and GPS analysis, Antarctic geodesy, and GPS network development, and eventually became section leader of the National Geospatial Reference System (NGRS) project.

Around that time, the National Collaborative Research Infrastructure Strategy (NCRIS) emerged as a possible way to fund research infrastructure. Together with Dr. Barry Drummond, Dr Phil McFadden, Prof. Kurt Lambeck and others, we identified the need for major infrastructure investment to achieve the high-powered national geospatial reference system to support Australian industries, and along came AuScope – the perfect vehicle.

What are you working on right now?

I’m currently head of the newly formed National Positioning Infrastructure (NPI) branch at GA. 
Our team is tasked with implementing Australia’s national geodesy program, and the two new positioning budget measures: the first on a Satellite Based Augmentation System (SBAS) and second on enhancements to Australia’s NPI capability, which significantly extends the existing GNSS capability (including AuScope infrastructure).

I am also Chair of the international GNSS service, which Is a scientific service under the International Association of Geodesy (IAG), I also co-chair of United Nations Global Geospatial Information Management Sub-committee on Geodesy, which aims to enhance the accuracy and sustainability of the global geodetic reference frame for the betterment of society. 

Can you share a happy accident or turning point in your work/research?

After 1994, I embarked on a dramatic career change from boundary surveying to geodesy,
which ultimately led me to become Australia’s chief geodesist, and chair of national and international committees which benefit our nation.

You recently won a Queen’s Birthday Public Service Award, congratulations!

Yes, I was very honoured to hear I’d been nominated, and very surprised, because I’m just doing my job! But it is very gratifying to be acknowledged by our community for the work I’ve done over an extended period.

Do you have an analogy that helps people understand what you do?

Well, everything happens somewhere. Geodesy is about establishing a reference frame with which we can measure where everything is, and more recently with advances in technology, it is about delivering that ‘where’ in real-time.

What is the biggest misconception about your work or field that those beyond it have?

That accuracy of positioning is not all that important. But as society continues to develop we see that needing to know where you are, with a higher and higher level of accuracy, becomes more and more important. Particularly where that knowledge is used to drive automation. 

We also need to monitor our planetary system to far better understand how it is changing through time, and what impact we’re having on it. I.e. anthropogenic science. For example, we need to be able to monitor surface subsidence due to oil, gas and water extraction, and the effect that it can have on the stability of the Earth (faults and earthquakes). Often these are occuring all in the same area such as in Gippsland, Victoria, so it’s critical that we know where and how these factors affect the environment.

How is your current work important in the real world?

It is important for efficiencies, safety and environmental management in a whole suite of industry sectors (mining, shipping, agriculture, environmental monitoring, hazard monitoring etc.) which can be enhanced by accurate and high integrity positioning.

How, and to what extent does your work depend on AuScope?

AuScope has been a very effective mechanism for us to develop research infrastructure. The AuScope investment has demonstrated both the value of the geodetic infrastructure to Australia, and also the flow-on research programs that can come from such investment. Both are now starting to produce great value for our society.

What are you most passionate about in geodesy?

I love geodesy because of the strong connection to science, it’s about understanding the Earth as a whole and how it changes through time. I love the large sense of scale in the field.

But I’m most passionate about communicating the value of positioning capabilities to countries that are less well placed than Australia, so that they can enjoy the economic, safety and environmental benefits that can come from geodesy. 

What inspires you outside of geodesy? What single question would you like answered in life?

I’m inspired by the life my parents lived. I’m not sure I could wrap all of my questions about life into a single question.

What are the big challenges and opportunities ahead in Australian geodesy?

As geodesy advances and accuracies improve, it becomes more complex for users – this is the challenge. But the opportunity lies with new ways of thinking and working, for instance the Internet of Things, with new mobile sensors: low cost positioning is becoming prevalent and will drive the mass uptake of advanced positioning in Australia.

Who would have thought that our phone positions will be accurate to within ten centimetres anywhere in Australia and its maritime zones? Within the foreseeable future you will be able to travel safely through downtown Melbourne or into the bush in a driverless car.

What’s it’s like to work in the Australian geoscience research community?

I like that geodesy is a global science, and that the Australian community is strongly integrated with the global community, take the International GNSS Service (IGS) for example, which contains over 500 people from over 200 global organisations. If there’s something missing domestically in terms of skills, then we can reach out globally. It’s also great that we have a young and actively developing geodetic community here.

Thank you so much for sharing your insights with us!

Is there anything we’ve missed?

Yes, my favourite colour is blue.



This interview was taken by Jo Condon of AuScope with Gary Johnson of Geoscience Australia.

If you would like to know more about Gary’s work with AuScope, please visit our Geodesy & Geodynamics program.

If you would like to learn more about geodesy, visit Geoscience Australia.