Calling all developing nations, underfunded scientists, and satellite imagery hobbyists. Care for a free "planetary-scale platform for environmental data & analysis"?
The Earth Engine, according to Google's press release , will allow researchers to study Earth's surface, especially deforestation, by trawling through a database containing trillions of data points from satellite images collected over the past 25 years and by viewing results with the Google Earth viewer.
The new product is Google's contribution to REDD, the idea that rich nations can compensate poorer countries for saving their forests. Deforestation accounts for a large slice of global greenhouse emissions. However, to implement a REDD scheme, researchers and national governments need better ways to accurately monitor carbon stocks.
Google says that is the idea behind the Earth Engine, which it first demonstrated as a prototype  last year at the climate conference in Copenhagen.
Via the Earth Engine, the Mountain View, California, software company says it plans to make available more than one petabyte of satellite data and will also donate 10 million CPU hours of computer time in its cloud-computing network. "Many of these images have never been seen, much less analyzed," Google said in its press release.
The Earth Engine was funded by Google.org , the search giant's philanthropic arm. According to Rebecca Moore, Google's lead on the project, the search company decided forest monitoring was a "Google-scale problem" because of the large amount of data involved and the complexity of algorithms to calculate carbon stocks. Find a detailed presentation by Moore here .
The tool could help poorer nations start to monitor their own deforestation problems. Some countries, such as Brazil, already have large teams studying images from satellites. However, other nations are only now building up such capabilities.
In developing its software, Google worked closely with leading remote-sensing scientists, including Matthew Hansen of the Geographic Information Science Center of Excellence at South Dakota State University in Brookings and Carlos Souza Jr. of the Brazilian nonprofit Imazon, which monitors deforestation in Brazil.
Another key contributor was tropical ecologist Greg Asner of the Carnegie Institution for Science in Stanford, California, who a year ago announced a partnership with the search giant. In a recent interview with Science, Asner describe the Google Earth Engine as, in part, a global-scale version of his CLASlite (Carnegie Landsat Analysis System Lite) technology, already the most widely used software for deforestation mapping.
"[CLASlite is] the most widely used software for deforestation mapping on the planet. But it's not global. So I partnered with Google, who are providing me with computing infrastructure, so I can scale up my system to the global level and stay at high resolution," Asner said. "We need high-resolution, transparent, global capability for monitoring not just deforestation but also forest degradation."
Google Earth Engine is still in beta phase and is available only to experts participating in testing, according to the U.N.-REDD program, which provides some detailed background  on the scientific content of the product.
Asner says he has been working with nine countries, including Peru, to build up remote-sensing teams capable of providing their governments with accurate data on forest stocks. "I think each nation should have its own monitoring capability, monitor their own forests; it leads to a series of positive outcomes," Asner said.
In Peru, for instance, monitoring efforts are headed by Doris Rueda of the Ministry of the Environment in Lima. Rueda says she has been working with Carnegie on a pilot program to compare forest cover and carbon stocks, in 2005 and 2009, in the Madre de Dios region of the Peruvian Amazon. If that analysis works, Rueda said, it will be extended to cover the entire country.
It's unlikely that the Google Earth Engine, which features widgets to remove cloud cover or pollution haze, will make such teams unnecessary. But it could help. Rueda says Peru's environment ministry is only 2 years old and still has much work to do before it can monitor its forests. "Although we have some people, it's not enough."
Google said it has already produced a forest cover and water map  working with CONAFOR , Mexico's National Forestry Commission. Google called that map "the finest-scale forest map produced of Mexico to date" and said building it required 15,000 hours of computation. Using approximately 1000 computers digesting 53,000 Landsat images, the map was completed in 1 day using Earth Engine.