In one high-profile case, native American Indians in the Amazon rainforest are using Google Earth alongside global positioning system (GPS) devices, notebook computers, digital cameras and satellite phones to reveal, record and map changes in their landscape that indicate illegal mining or logging operations.

This is just one of a growing number of non-profit and academic initiatives making use of free or low-cost satellite data and tools to monitor environmental phenomena or to expose damaging practices that would otherwise be hidden from view.

Scott McGee, a surveyor with the Juneau Icefield Research Program in Alaska, US, is using Google Earth to map and monitor the changing boundaries of 13 glaciers in the icefield. The Mountain Resource Group, a campaigning organization in Northern California, uses the same internet tool to create models and fly-through views of controversial logging proposals in the area.

Farther east across the US, SkyTruth has just released a video. This illustrates the rapid and extreme changes that are occurring in Wyoming's Upper Green River Valley (a wildlife-rich area of "spectacular natural beauty" that is part of the same sensitive ecosystem as Yellowstone Park) as a result of the drilling, road construction and pollution accompanying the development of extensive natural gas fields in the region. The video combines satellite imagery, aerial photography and Google Earth technology to give an unprecedented insight into the environmental impacts on the area.

The founder of SkyTruth, John Amos, has a background in satellite remote sensing and image processing for oil and gas companies. He established SkyTruth so that he could deploy the same technical expertise in support of environmental efforts.

SkyTruth's aim is "to help environmental groups to understand and communicate the issues they're working on," Amos told environmentalresearchweb. "We started before Google Earth, using our expertise to select raw data from the appropriate satellite system – such as Landsat or RADARSAT – and process it into a useful format, such as a map or an image."

Amos says that Google Earth has provided a revolutionary democratization of this technology. "Now we can embed our custom imagery into the Google Earth interface," he explained. "A rising tide lifts all boats; Google Earth has raised interest and awareness and provides a simple tool that our partners can use. SkyTruth adds the value, for example by providing up-to-date or high-resolution imagery."

It's too early for Amos to say whether his efforts have curtailed environmentally damaging activities, but he believes that the trend is a positive force in itself: "If this imagery is ubiquitously available, it is likely to discourage people from doing bad things".

The outcome of the Amazon Rainforest initiative is more definitive. A spokesperson from the Amazon Conservation Team, which coordinated the project, told environmentalresearchweb that the combination of satellite technology, indigenous territory knowledge and training for local people has resulted in clearly improved protection and land management. In fact, one community was able to stop forest clearing for a gold mine.