Sir

Your News in Brief story “Enthusiast uses Google to reveal Roman ruins” (Nature 437, 307; 2005) made me wonder whether the time for a new conservationism is not already on the horizon. A time when the convergence of imaging and grid computing technologies, together with a policy of free access to catalogues of high-resolution Earth imagery, will make it possible to monitor selected patches of forest across the globe using the Internet.

Indeed, new instruments such as the wide-field imager to be launched with the third Chinese–Brazilian Earth Resources Satellite in 2008, with a spatial resolution of 70 metres and a revisiting time of less than a week, are ideally configured for this task.

This resource will be free of charge to users in Brazil and could be in other parts of the world too, depending on agreements with their governments. Meanwhile, a lower-resolution resource, MODIS, is already available at http://modis.gsfc.nasa.gov. Although rainforests are often covered by clouds, reducing the amount of time that data are available, the large numbers of potential watchers would maximize the use of data.

Today, thousands of enthusiasts are using their home computers to search for signs of extraterrestrial intelligence. Perhaps there could soon be a global network of forest-watchers, pushing the alarm button every time their protected gardens are under threat.