Google Earth Engine Shows San Diego's Changing Landscape
A new tool called Timelapse by Google allows users to see how the Earth has changed over the past 30 years.
Google Earth Engine is a data repository and mapping tool for scientists, developers or anyone interested in changes to Earth’s surface. Part of the Earth Engine contains a global, interactive video time-lapse made from more than 5 million images from five different satellites. Here’s a link to everything technical.
This is San Diego from afar (not much changing at this level, but hit play in the bottom left to get the hang of it):
It’s when you zoom in that things get interesting. Look at eastern Chula Vista, which exploded outward in all directions in the mid-‘90s to fill in the land between Interstate 805 and Lower Otay Lake. Relatedly, the city’s population nearly tripled in that time period: from around 84,000 people in 1980 to an estimated 266,000 in 2015. Watch it happen:
The Sweetwater Reservoir appears to breathe in and out over the decades, then shrink over the past five years to its current low levels. The data backs this up: In November 2010, the reservoir contained more than 12,000 acre feet of water. Today it holds little less than 2,800 acre feet — a drop of more than 75 percent.
And watch Mira Mesa, Sorrento Valley and Carmel Valley mushroom alongside construction of State Route 56, which linked Interstate 15 and Interstate 5 in 2004.
This bird’s-eye view pales in comparison to what can be achieved by more experienced users, who can add layers of climate, demographic or geophysical data, create time-lapse tours, or even contribute their own data. You can also browse the work of academics and nonprofits who have used Google Earth Engine for things like surveying global tree cover, tracking changes in endangered wild tiger habitats and predicting malaria outbreaks.
Play around a bit. Let us know what you find.