Google Earth has launched a time-lapse feature that lets users wind back the clock and see how the planet has changed over several decades.
The feature uses many satellite images from the past 37 years to let people scroll through time.
It allows people to ascertain, for instance, the retreat of glaciers alongside heating, or the deforestation of the Amazon over time.
The company says it’s the most important update to Google Earth in four years.
Google Earth uses similar technology to the widely used Maps product but is more focused on geology and exploration than conveyance and directions.
Users can access the tool during a browser, and therefore the feature comes with some pre-packaged virtual tours of an Alaskan glacier melting over the years or forest protection efforts in Brazil.
But the time-lapse feature is global – meaning users can just type in any location and experiment with whatever images are available.
Google is heavily marketing the tool as a way to raise awareness of climate change and other environmental issues.
It pointed to the shifting sands of Cape Cod and therefore the drying of Kazakhstan’s Lake Aral as striking samples of how the landscape is changing.
But it also documents the boom in towns and cities across the planet – from the rapid expansion of Las Vegas to the building of artificial islands in Dubai.
“We have a clearer picture of our changing planet right at our fingertips – one that shows not just problems but also solutions, also as mesmerizingly beautiful natural phenomena that unfold over decades,” Google said.
An Earth-sized video
Under the hood, the remake of Google Earth is powered by 24 million different satellite photos, from Nasa, the US Geological Survey’s Landsat project, and therefore the EU’s Copernicus project.
Google said the new features “simply wouldn’t are possible” without the “commitments to open and accessible data” from those space agencies.
While the typical user will only see a small fraction of the system at a time, Google says the animated time-lapse imagery is one giant video mosaic, made up of individual video tiles.
The 24 million images go back as far as 1984, and take up 20 petabytes – 20 million gigabytes – of space for storing, and “quadrillions of pixels”, the corporate said.
Together, they make one single video 4.4 terapixels in size – something Google said is the equivalent of more than half a million 4K ultra-high-resolution videos.
Processing all that data took quite two million hours of computer time-shared among thousands of high-powered machines owned by Google to urge the work wiped out a reasonable timeframe.
“As far as we all know, time-lapse in Google Earth is that the largest video on the earth, of our planet,” the corporate said.
That kind of heavy processing in air-conditioned data centers uses vast amounts of power and has a significant environmental impact. Google argues that all its data centers are carbon-neutral, though it does this through the practice of offsetting – paying for environmental projects to “balance” its use of energy.
The huge amount of historical data also has other practical benefits – like removing clouds. Anyone set of photos from the Earth’s surface will have areas obscured by cloud cover that the satellite can’t see.
But over time, different pockets appear, which may then all be stitched together to make an image of what is underneath.
Google says it plans to update this new time-lapse project per annum for a minimum of a subsequent decade.
“We hope that this perspective of the planet will ground debates, encourage discovery, and shift perspectives about some of our most pressing global issues,” it said.