With the advent of commercial satellite imaging, it has become possible to track developments that were once exclusively the domain of space and spy agencies. Groups like the Federation of American Scientists and the American Association for the Advancement of Science have used changes between consecutive images to track everything from the Chinese nuclear program to human rights abuses in Sudan. Each of these efforts, however, have required people to examine the images. Google has now cooperated with some researchers to produce an algorithm that will scan consecutive images of forests in order to detect areas that are being cut. Right now, it's still testing the system, but it plans on providing free access to the software for researchers who are interested in studying forests, and governments that are trying to manage them.

The project was announced today in Copenhagen, where delegates are meeting to negotiate a treaty that may limit greenhouse gas emissions. Forests play a significant role in the global carbon cycle; clearing them liberates significant amounts of carbon, a process that takes decades to reverse. Growing forests can help sequester significant amounts of carbon, and there is evidence that even mature forests continue to sequester smaller amounts. As a result, land use changes have contributed to humanity's carbon emissions, and countries that preserve or expand their wooded areas have argued that they deserve emissions credits for doing so.

But actually tracking the changes in forestation can be a significant challenge, since it generally takes place across vast tracks of remote land and satellite imagery may be beyond the financial reach of developing-world governments or the research organizations that work with them. Furthermore, it's essential that nations use a standardized, validated method of measuring changes, or it will leave any emissions tracking system open to misinterpretation, and any credit system open to abuse.

The new Google effort, which was announced on its blog today, aims to provide those standardized tools. Google has been cooperating with charitable groups like the MacArthur and Gordon and Betty Moore Foundations to support the development of software tools that help analyze satellite imagery to detect changes and trends in forest cover and health. These tools have now been ported to run on Google's cloud computing service, and to leverage the archive of satellite images it hosts for its Maps and Earth services.

Right now, the software is still undergoing testing by some of Google's partners—insert your joke about the company's penchant for near-perpetual betas here—but the company expects to expand the organizations with access to it next year. But, even as things stand, there's a large and impressive list of organizations that are involved with the work. When it's ready to go live, access to the service will be provided for free through the company's Google.org initiative.

So far, the news coming out of the Copenhagen meeting has been dominated by statements meant to inform policymakers of the current state of the climate. These have included a preliminary estimate that places this decade as the warmest in the instrumental record, and an update on the progression and consequences of ocean acidification. Although these may inform the current negotiations, it's rather refreshing to see the release of a tool that has the potential to inform future scientific and policy discussions.