Making sense of the world an old idea, new technologies offer ways to do it better than ever
December 2, 2008
A Babylonian clay tablet dating from 600 B.C. is the oldest map of the known world, although not a whole lot of the world was actually “known” at that point.
The Chinese, Egyptians and Mesopotamians used string and bead abacuses to make calculations at least as early as 3000 B.C. Ancient Alexandria boasted data collections—in the form of a library filled with papyrus scrolls.
When the brothers Montgolfier first got a look at the ground in France from the vantage of their hot air balloon in 1783, they were engaging in remote sensing, in a sense. In 1903, German engineer Julius Neubronner combined a small camera with a mechanical timer strung around a homing pigeon's neck for aerial photography. Before long, airplanes were carrying the cameras.
Today, “spatial data infrastructures” national, regional and global in scale rely on a satellite’s sensor suite view of the world rather than a bird’s-eye view. The systems employ and integrate myriad data collections from satellite and other remote sensing techniques—as well scientific and demographic material, for example, collected on the ground—sifted by powerful supercomputers.
But the idea is the same: to make some sense of the world. And no longer just for the U.S. and fellow developed nations, which have long experience building and using such tools for military, scientific and other purposes, said Gilbert Rochon, who directs the Purdue Terrestrial Observatory, part of Information Technology at Purdue (ITaP) and its Rosen Center for Advanced Computing.
Spatial data infrastructures are appearing in, and have relevance for, places such as Argentina and Brazil, Nigeria and Thailand, in addition to less surprising venues like tech-savvy China, India and Israel. More than a dozen countries now have middle- to high-resolution Earth-observing satellites in orbit and the number should top 20 by decade’s end. China, Japan, Australia and other Pacific Rim nations are working on a regional system as is the European Union.
“There’s a big push on for a global spatial data infrastructure,” said Rochon, who also is associate vice president for collaborative research in ITaP and chief scientist for the Rosen Center.
Rochon has been discussing the future of spatial data infrastructure technology and its implications worldwide recently.
In October, he was a keynote speaker at the Korean national conference on spatial data infrastructures. Purdue agronomy, civil engineering and electrical and computer engineering Professor Melba Crawford, assistant dean of engineering for interdisciplinary research and director of the Laboratory for Applications of Remote Sensing at the University, also presented a paper at the conference, on advances in LIDAR (for light detection and ranging), an optical remote sensing technology that measures properties of scattered light to generate information about a target.
Rochon in October also spoke about a potential use of spatial data infrastructures—early warning and mitigation of vector-borne and zoonotic diseases—at the African Association for Remote Sensing of the Environment meeting in Accra, Ghana. The first author of the paper, Joseph Quansah, earned his doctorate at Purdue in agricultural and biological engineering and is a postdoctoral researcher here.
You can think of a spatial data infrastructure as a geographic information system writ large, or “enterprise GIS,” as Rochon put it. More than just maps, the idea is a unified system for ready access to standardized data from a variety of sources that can be rendered visually and geographically to generate knowledge and aid decision making at all scales for multiple purposes.
“There are a host of potential applications,” Rochon said.
Those applications range from routine local governance issues, like planning the location of a new fire station and other land use issues, to illuminating the effects of global climate change. Changes in land use like deforestation and urban sprawl, the impact of weather and natural disasters, socio-economic and demographic trends, pollution and more—all could be brought into the perspective by the techniques and, perhaps, be better managed as a result.
But Rochon said the grand challenge for the technology is really to apply it to addressing issues important to humanity, the spread of disease or famine, food and water security, sustainable development, poverty, disaster mitigation, and mitigating the effects of armed conflict among them.
Inclusion and equitability for developing nations and rural areas, which may lack the necessary financial and human resources and essential components like fiber-optic networks, high performance computing facilities and satellite tracking stations, even an adequate power system, also are a challenge, Rochon said.
Purdue has been involved in remote sensing research for more than 40 years. The Purdue Terrestrial Observatory gathers masses of satellite and other remote sensing data along with information collected from ground-truthing instruments and activities, which allows the data to be mined for knowledge by researchers from an interdisciplinary array of fields as well as by local, state and national decision makers.
Resources like the Purdue Real-time Satellite Information Gateway (PRESTIGE) and Purdue-developed HUBzero (an easy-to-use, yet sophisticated Web portal development system) can be used to make the data and tools to use it readily available via the Web and the TeraGrid, the world’s largest network for open science computing.
Rochon noted that Purdue is the lead institution in IndianaView, a statewide consortium of universities, state organizations and non-profits, which is a member of AmericaView, a nationwide program that focuses on satellite remote sensing data and technologies in support of applied research, education, workforce development and technology transfer for what is essentially a U.S. spatial data infrastructure.