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Many geospatial technologies will be impacted by three and four dimensional geographic information systems (3D GIS). Some technologies like global positioning systems (GNSS), remote sensing and laser based technologies will enjoy a thrust forward as new forms of data capture, management, analysis and representation are supported through thinking about applications in 3D. Visualisation will be significantly impacted because 3D and 4D analysis will propell new representations into the limelight. We are truly entering a new phase of exploration and discovery in the geospatial sector.

Three and four dimensional spatial information is not a new concept. Current technologies and approaches like lidar, GPS and stereoscopyhave been available for some time.

But most people have settled upon 2D visual ques and analysis in their day-to-day work flows. While we have consciously, at some level, been well aware of the 3D nature of spatial information, most common approaches to spatial information have been about identifying places, features and attributes on 2D surfaces, drawings and work environments. This has (and will continue) to serve us well.

3-D and 4-D information, particularly when supported by analysis, processing and integration software can open the door to whole new ways for thinking about everything we see and do.

• Picture a farm producer traveling across a field. In the cabin of the tractor is a complete picture of the farm – below ground – displaying soil moisture content and level of soil N, P, K and S (as well as a few micro-nutrients). Models running in the tractor, based on the information as ‘decision-making’ where and how much fertiliser to apply. This sounds like a typical precision farming application, but it’s not. Soil moisture by depth significantly impacts rate and amount of infiltration and soil moisture by depth is slope and aspect dependent – 3D.

• Imagine a lidar pount cloud. It consists of about 100 million data points. Rather than displaying all of these points, it is decided to display only those for areas previously processed in 3D through GIS analysis. That is, a 3D polygon has been determined. Picture a bomb blast or an atmospheric release of gases within a 3D space and you want to know what objects (determined by point cloud) will be impacted. Perhaps modeling the wind flow through these spaces.

• Think of a GNSS application with a GPS receiver. Your job is to representively sample a 3D space. How do you pre-program a GPS to take samples (locations – measurements) in a 3D space?

• How would you create a 3D visualisation of a ‘what-if’ scenario? How would you display a series of remotely sensed images witin a 3D space? We have all seen pictures rotated in 2D space – flipped back and forth. Is this where levels of visualising uncertainty come in, where fuzzy boundaries begin to take shape?

Lidar and laser technologies have a direct relationship to 3D place and time. Each point is held directly in 3D-4D.  This is not a new development, but it raises the question as we think about modelling and analysis, how do these raw data become more directly related to other technologies and applications. More importantly, it also means that each individual point within a cloud becomes more valuable, and why they should be maintained.

It would seem that modelling and design are likely to be the first areas to benefit by closing the gap between 3D geospatial data creation and 3D geospatial application use. This is already evident in the 3D city design space, electrical substation design areas and the modelling of atmospherics, for example.

There will be a need to educate people about the benefits of 3D data tools and the applications derived through the use of 3D and 4D data. Can we safely assume that people will know what to do with advanced tools capable of directly collecting 3D and 4D spatial data? Probably not. Although many developers have worked toward simplifying applications, the development of new applications based on 3D and 4D information is an entirely different consideration.

The prospect of extracting 3D value from already existing spatial information held within archives holds considerable promise. But to acquire that benefit will mean that access to those archives must be expanded and exploited. To achieve this require planning. But the coupling of automatic data extraction tools ought to be able to expedite the work flows and expose this information reasonably quickly.

The development of 3D technologies will increasingly involve an interest in time and the development of continuous 3D applications. Real-time information and results will become the expectation. Keep in mind that 100m resolution imagery once every 6 months appeared normal only 2-3 years ago, but has been replaced with the expectation of updated imagery on a regular basis and ‘see your own backyard’ mentality.

The chore ahead will require that we understand the spatial information and what it is saying. That is no different than today, but it would be more desireable to have tools for quantifying quality.

In summary, 3D GIS will significantly impact geospatial technologies. Immediate benefits will apply to those technologies that are directly capable of providing 3D enabled modelling, analysis and representation. These include lidar, laser and GNSS devices. It is difficult to tell if surveyors have grasped the importance of these changes. The applications and use of the generated information will require greater use of survey tools and techniques, but for non-survey related applications involving communication – visualisation, modelling and spatial analysis.

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Jeff Thurston is editor of V1 Magazine and V1 Energy Magazine for Europe, Middle East and Africa. This column rotates weekly.