By Stephen Peedell
JRC Institute for Environment and Sustainability
Ispra, VA-21027, Italy
Though we may not use them as often as we did before, many people have some nostalgic memory of globes. Those who are 30 or older most likely recall them from the classroom, where they were a common feature before widespread personal computing and digital visualization of the Earth, Geographic Information Systems and, more recently, 3D virtual globes. Yet predictions that globes are no longer relevant or necessary may be premature as the representation of the Earth system in miniature, as a physical, tangible sphere still has a particular fascination and appeal. The combination of a physical sphere with digital visualization technology to create hybrid digital spherical displays heralds a new age of globe usage that is no longer constrained by a one-off printing process or a display on a two-dimensional screen. This unique perspective of Earth provides us with new opportunities to present global scientific observations in an intuitive and engaging way, and in an environment where groups of people can participate in conversations about key environmental challenges.
The ability to visualize the Earth has changed dramatically in a very short period. The KeyHole Earthviewer, the predecessor of Google Earth, was launched in 2001. Google Earth reached 1 billion downloads within six years of its release in 2005, and has revolutionized the use of geographic information. In this high-tech, virtual world, it could be thought that tech-savvy citizens with the world on their smartphone would have limited interest in the idea of a traditional globe. That’s not necessarily the case. If you can create the effect of a traditional globe, enhance the by displaying multiple maps and add animation and other effects, then you have something that will genuinely draw attention. In 2011, the European Commission’s Joint Research Centre (JRC) began working with a digital spherical display – the OmniGlobe – a 150 centimeter in diameter, internally projected sphere capable of displaying, rotating and animating images, specifically maps of the world and global environmental datasets. It was immediately obvious that this spinning blue marble had the power to engage an audience far better than displaying the same data on a two-dimensional screen. People could walk around the globe and, with a live presenter to animate the discussion; it was possible to stimulate lively and informative debates in a very short time. Audiences could range from school children to researchers and politicians to grandparents – all with their own perspective and interest. The display puts the whole world in front of the user, allowing them to virtually circumnavigate the globe on foot in 30 seconds.
As an international research center, the globe has enormous potential as an awareness and educational tool for our work. In 2012, the JRC acquired its own OmniGlobe, with dual high definition (HD) projectors and an interactive touch terminal kiosk for selecting different themes to display, based on the OmniSuite software. Now, by pressing a button, visitors can visualize anything from continental drift to sea surface temperature variations and aircraft movements across the globe. The dual HD configuration is brighter and has better resolution than single-projector globes.
We are now hard at work compiling the many examples of our scientific datasets to create compelling exhibits for the globe, covering themes including environment and climate change; energy and transport; agriculture and food security; land resource management; natural disasters and public safety. We are also building a semi-permanent home for the globe at our site in Ispra, Italy, where a new dedicated visitor center will be inaugurated this May, on the occasion of the site’s bi-annual Open Day. In the meantime, the globe has been rolled out across Europe, being featured at exhibitions, conferences and science fairs, and has been a centerpiece for high-level visits to the JRC. Although the globe itself weighs less than 20 kilograms, it is still a bulky piece of equipment to transport. However, with the internal projection system it can be set up by our technicians in a few hours, as opposed to fixed external projectors, which require precise alignment and are dependent on the globe remaining in a fixed position. Rectangular maps developed and symbolized using a standard Geographic Information System and exported in one of the common image formats, such as JPEG or PNG, can be displayed on the globe. In fact, the globe software will display any image of these types, but most often the image is a map. As long as the map is rectangular and covers the entire world from -90 degrees South to +90 degrees North, and -180 degrees West to +180 degrees East (i.e. a map in Plate Carrée projection), then the OmniSuite software will correctly wrap this for display on the sphere.
Telling a story with the globe has specific challenges. You can change the maps being displayed, but the scale is fixed. Text has to be used with care as it distorts when it is wrapped on the globe’s surface. Maps must be vibrant, and largely self-explanatory. Lighting and layout of the globe exhibit space are crucial factors to create an effect that will impress visitors. Most importantly, the story needs to be clear. Merely displaying a map, which may in itself be visually attractive, is not enough. For example, using data on earthquake occurrence from the Global Disaster Alert and Coordination System (GDACS), managed by the JRC, the globe can display areas of high risk of seismic activity. By preceding this with an animated reconstruction of the movement of continental plates over geological timescales (paleogeography), visitors can easily understand the dynamic nature of the Earth’s crust and the consequent prevalence of earthquakes where these plates meet. Similarly, the display of maps of global crop forecasts, produced by the JRC team working on food security, is explained by showing the various input layers — land cover, soil type, meteorological and climatic conditions, soil moisture and water availability — that make up the agro-meteorological models developed by the JRC. Drought is one area of specific concern. JRC specialists are particularly interested in identifying and mapping agricultural drought. By combining information on soil structure, rainfall, temperature and the water requirements of growing crops, we derive a Global Water Satisfaction Index (GWSI) in near-real time. This information is used on the global scale to identify locations where there is not enough soil moisture to support growing crops. This allows the identification of hotspots of agricultural drought and locations that are more susceptible to food insecurity. Visualizing this kind of information on the globe provides an overview of the global situation and how many different places may be suffering simultaneously. Droughts develop over time, and we also are able to visualize the evolution of these events, showing how they are a product of both their geographical extent as well as their severity.
The Emissions Database for Global Atmospheric Research (EDGAR), hosted by the JRC, has more than 40 years of emissions data for which we will develop globe animations. The first Global Soil Week, held in November 2012, featured a series of globe presentations by the JRC in order to raise awareness of the essential role of soil resources to ensure sustainable development, to support ecosystem services, biodiversity conservation and climate change adaptation and mitigation. The JRC-developed Global Marine Information System (GMIS) as an extensive archive of satellite observations of the oceans, which can be animated on the globe to show seasonal variations and anomalies in sea temperature and productivity.
Or, you could take a more historical view and reproduce the oldest known globe in existence; that made by Martin Behaim in 1492, the so-called erdapfel. Hailing from the golden era of exploration, it illustrates nicely the benefits of being able to update the map being shown – the erdapfel globe does not include the Americas, the discovery of which was not announced until Columbus’ return to Spain the following year. In the ensuing 500 years, globes have evolved from scientific and navigational instruments to status symbols and educational tools. The digital globe is the next generation – still with the simple wonder of a spherical display, combined with the sophistication and power of digital imagery.
Stephen Peedell has worked with Geographic Information Systems for the last 20 years, with extensive experience in data integration and visualization, and building applications and spatial databases in a wide range of fields including agriculture, biodiversity and transportation.
By Stephen Peedell