Community Remote Sensing

IGARSS 2010 Theme

Ray A. Williamson, PhD, is editor of Imaging Notes and Executive Director of the Secure World Foundation, an organization devoted to the promotion of cooperative approaches to space security (

For nearly the first three decades of satellite remote sensing, the utility of the data was limited by the expert knowledge of complex software required to make full use of the data’s capabilities. The software and training needed conspired to make this difficult. Even governments and well-heeled companies were slow to incorporate the benefits of this powerful space technology into their operations. However, over the past decade the proliferation of GPS applications and the development of simpler geographic information systems (GIS) tools have broadened the attractiveness of satellite data.

At the same time, in order to keep pace with the competition presented by the digital format of satellite remote sensing, aircraft sensing has evolved to use large digital cameras and radar devices for specialized high-resolution information products, adding new depth to the marketplace. Satellite and aerial remotely sensed data are now much easier to incorporate into business and government processes than ever before.

I would argue, however, that the really big breakthrough in market access to data came with the advent of Google’s Google Earth Web application in 2005. Nearly instantaneously, Google Earth brought millions with access to the Internet a quick way to see what their neighborhood looked like from space, or to look back on their childhood home. It also allowed business people rapid access to information about potential future business locations. Yet its real power is in the hundreds of applications that individuals, non-governmental organizations (NGOs), and businesses have developed using the application. For example, the website, uses Google Earth to display the places mentioned in the Bible. Also included is extensive information about the site and its relationship to the books of the Bible.

What excites me about the ease of use that Google Earth and Microsoft’s Bing Maps platforms provide is that they supply the stage for involving ordinary citizens in taking better control over their own local environments by using remote sensing to influence policymakers. For example, Appalachian Voices, an environmental advocacy group in the Eastern United States ( has used Google Earth and a plethora of local data gathered by citizens to show the sometimes disastrous effects of mountaintop coal removal on local communities located down slope from the mining operations (Imaging Notes, June 2007).

The key here is the incorporation of local data into the overall picture that Google Earth provides. Ground level digital photographs (another form of remote sensing) and videos (yet another form of remote sensing), and audio clips can be incorporated into the mix of information to provide a compelling and detailed story that policymakers respond to.

Sensing severe weather from automobiles

Distributed data collection uses the community to augment centralized remote sensing data sources. This figure illustrates how simple weather sensors on automobiles can greatly enhance our ability to detect severe weather events. The color scale represents the Doppler radar data in a portion of Texas and shows an area of severe weather that could be a forming tornado. The labeled items are current weather data from fixed stations, while the non-labeled items (in light blue) are weather obtained from a moving automobile. A distinct change in wind direction is observed by the automobile as it approaches the storm center, indicating inflows at ground level characteristic of tornado formation. This information is not available from either the fixed weather stations or the Doppler radar. Automobiles are already equipped with useful temperature and pressure sensors; simple rain and wind sensors could be readily added. Drawing data from the community of millions of vehicles on the road would complement our centralized satellite and ground-based weather data sources, enabling us to forecast development of severe weather and micro-weather with unprecedented accuracy. Image courtesy of Scott Blair, National Weather Service.

What now makes it easy to bring local data into the picture to provide additional granularity to aircraft or satellite images are the many new digital applications, such as SmartPhones, netbooks, and other wi-fi and internet applications. Facebook, Twitter, and other citizen news feeds from the recent unrest in Iran following the disputed presidential election provide ample proof of the power of using these new tools to gather information quickly and efficiently. Need to gather photo data quickly on a given area? Twitter your colleagues to pick up their GPS-capable digital cameras, or better yet their camera cell phones and send you the pictures, with the GPS information built in.

More sophisticated uses could include temperature and pressure measurements, encoded with location and time coordinates, obtained from individual mobile phones, and sent to a central location to contribute to the creation of high-resolution weather models of an area. This would be the logical extension of applications like the well-known WeatherBug Internet that relies on weather observations at small weather stations at schools around the United States to provide local weather information.

In another application, students at the International Space University this summer at the NASA Ames Research Center in California developed a SmartPhone application designed to enable the quick and efficient collection of data about urban buildings (number of floors, age, type of construction). The data, which can be collected by a few teams of university students in a relatively short time, would be added to the aerial and satellite data available for Belize. They are intended to be used to populate a World Bank-developed database designed to assist the country of Belize in reducing its risk from natural disasters.

Virtual Disaster Viewer

Distributed analysis uses the community to rapidly extract knowledge from raw remote sensing data. This figure shows a software tool called Virtual Disaster Viewer (VDV) developed by the company ImageCat. With VDV, imagery of disaster regions such as earthquakes can be rapidly communicated via the internet to a large network of analysts. These may include known experts, pre-qualified volunteers, or perhaps even anyone who is accessing the internet and is knowledgeable about the affected area. The tool segregates the analysis by grid area to distribute the task and provides a variety of functions to assess the situation and rapidly inform decision-makers of needed actions. The use of community speeds up time-critical tasks that might otherwise take centralized organizations hours or days to complete. Image courtesy of Beverley Adams, ImageCat.

The possible applications of such a mash-up of distributed observations and remotely sensed data from aircraft or satellites are limited only by the human imagination. The importance of such capabilities for enhancing human security cannot be understated. They contribute in two important ways: first, they enable the rapid collection of local information that can provide greater depth to the interpretation and understanding of local and regional environmental and geographical conditions; and second, they enable local people to engage directly with their communities and thereby take greater charge of their own destiny.

In recognition of the growing importance of community remote sensing through citizen science and social networking to communities around the world, the 2010 annual IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2010), to be held July 26-30 in Honolulu, Hawaii, has adopted the conference theme of “Remote Sensing: Global Vision for Local Action” ( Indeed the conference will begin with a plenary session entirely devoted to the topic of community remote sensing.

IGARSS plenary organizers are soliciting the participation of organizations that are pursuing projects embodying the plenary theme. They will be looking for projects that demonstrate their promise to create either new knowledge or new technologies associated with community remote sensing. In light of the promise of community remote sensing to improve the delivery of the benefits of space technologies to ordinary people, Secure World Foundation plans to sponsor the IGARSS plenary session.

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