Historical imagery in Google Earth gives professionals a visual record of how the planet evolves over time. We’ve heard how much users love the ability to time travel all over the planet and while historical imagery is incredibly valuable, we think we can do even better. Finding specific changes and context manually can require significant, manual, repetitive work: toggling between individual capture dates, panning across large areas, and scanning pixels by eye to spot construction, land clearing, or new development. What if Google Earth could help you highlight changes across time and space?
Today, we are introducing detect change, an experimental tool in Google Earth to find where and when change has occurred anywhere on Earth. Powered by Google's latest geospatial AI technology, the tool compares Earth observation data between two annual intervals, generating a 10-meter resolution heatmap layer to fast-track your work. Detect change is available today on Google Earth web for Standard plan users, with expanded capabilities available on professional plans.
Real-world applications
Professionals can integrate detect change directly into planning, environmental, and analysis workflows to save significant time at work. Here are a few examples:
1. Urban planning and municipal growth tracking
Urban planners like Alejandra Macarena Tomietto use Google Earth to analyze vast metropolitan areas to track urban expansion, infrastructure needs, and environmental risk. While mapping 2,567 square kilometers across Buenos Aires to protect 400,000 residents living in high environmental risk zones, Tomietto combined Google Earth's historical imagery with data layers to visualize development patterns and inform better planning decisions for the future of the city:
"Google Earth helped us anticipate the future by showing real-world development patterns. By observing how these patterns were developing, we could predict where the city was expanding and identify open spaces available for services. It turned a mountain of abstract geographic data into a clear, visual language that we could actually use to plan effectively. We were tackling something deeply complex, and Google Earth made it feel easy."
With detect change, professionals can save significant time during multi-year comparison workflows like this.
2. Environmental protection and conservation
Land trusts, forestry analysts, and environmental consultants monitor large tracts of land and protected ecosystems. Instead of inspecting large areas manually, conservation teams can use detect change to verify that protected areas remain undisturbed and identify exact locations requiring intervention.
3. Site analysis
In early-stage workflows, professionals may need to evaluate a site’s historical context, neighboring development, or burgeoning infrastructure before committing resources or visiting. Using the tool to look for change on site and the surrounding area reveals prior activity earlier in due diligence.
Beyond the visible spectrum: How Google Earth detects change
At the core of the tool is the annual AlphaEarth Foundations Satellite Embedding dataset. Rather than comparing red, green, and blue pixel values alone, the model analyzes a multimodal synthesis of Earth observation data:
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Optical and multispectral imagery: Evaluates surface reflectance, vegetation health, and spectral land-cover indices.
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Thermal signatures: Measures surface heat retention to distinguish natural ground cover and bare soil from dense asphalt or concrete roofs.
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Synthetic aperture radar (SAR): Transmits active radar pulses that penetrate clouds and atmospheric haze to measure physical surface roughness, structural mass, and geometric elevation changes.
By fusing radar observations, thermal measurements, and multispectral imagery into a unified representation called an "embedding" for every 10-meter patch of Earth, the model is smart enough to help prevent mistakes made by tools that use imagery alone. This multi-sensor approach shapes how you interpret results in Google Earth:
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What it detects: The model even identifies physical ground shifts that remain invisible in standard optical photography.
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What to keep in mind: Because the model senses physical properties beyond the visible spectrum, the heatmap may show surface changes that are not immediately obvious when looking at historical imagery in Google Earth.
How to use detect change
Follow these four easy steps to generate and inspect a change detection heatmap in your project or watch our full tutorial.
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Open the tool and explore the live preview
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Choose any two baseline and target years between 2017 and 2025, draw your polygon, and hit ‘Create layer’.
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Once the heatmap is added to your map, use imagery to inspect where change occurred:
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Yellow heatmap zones: Brighter, denser yellow clusters mark locations where Google Earth detected significant changes between your selected years.
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Historical imagery: Zoom into an area with dense heatmap activity, open historical imagery, and jump directly to the two baseline and target years you selected in the tool.
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Street View imagery: Drop the pegman onto adjacent roadways to conduct a virtual site walk and inspect ground-level details from historical Street View imagery.
Get started with detect change today
Evaluating how sites, cities, and natural landscapes evolve no longer requires hours of manual pixel scanning. Combine detect change with historical imagery and Street View imagery to move directly from broad scanning to ground-level verification. Open Google Earth on web or Android to use detect change on your next project.
