Global Scene vs Local Scene in ArcGIS Pro

In ArcGIS Pro you can create both global and local scenes, each suited to different kinds of spatial data and project needs. Understanding when to use a global versus a local scene can significantly enhance your 3D data visualization, analysis, and performance.

Global Scene

A global scene is designed for visualizing and analyzing large areas, such as continents, countries, or even the entire planet. It projects data onto a round, earthlike surface using a WGS 1984 coordinate system, which assumes a 3D spherical earth model.

Why and When to Use a Global Scene

Large geographic areas: When working on datasets that cover regions spanning thousands of kilometers (e.g. satellite imagery, global climate models), a global scene is ideal.
Curved Earth visualization: If you need to visualize the curvature of the Earth, such as for long-distance flight routes, global transportation networks, or satellite trajectories, a global scene provides a more accurate representation.
Online services: Many basemaps and elevation models in ArcGIS Pro (e.g., from ESRI's Living Atlas) are designed for global scenes.
3D elevation models: Use global scenes when integrating global elevation data for large regions or if your elevation data spans multiple countries.

Tips for Global Scenes

Optimize performance: Since global scenes often involve large datasets, use cache settings and optimize layer visibility to avoid rendering unnecessary details for distant locations.
Use vertical exaggeration: To highlight terrain features (like mountain or ocean depths) that might otherwise appear flat, apply vertical exaggeration.
Coordinate with Web GIS: If you are sharing your scene on ArcGIS Online or ArcGIS Enterprise, a global scene is the better option, as it aligns with global basemaps and elevation models.

Local Scene

A local scene is typically used for smaller, more focused geographic areas. It projects data onto a flat plane and can be configured with any projected or geographic coordinate system. Local scenes are ideal when accuracy in the x, y, and z dimensions is crucial for a limited spatial extent.

Why and When to Use a Local Scene

Small, detailed areas: When your focus is on a city, a park, or a construction site, a local scene offers better spatial accuracy and performance.
Building and infrastructure modeling: Use local scenes to work with detailed 3D models of buildings, roads, and other infrastructures where the curvature of the Earth is negligible.
Custom coordinate systems: if your data requires a specific projected coordinate system for a region (e.g., UTM), a local scene allows you to define and control this projection.
Underground data: For subsurface analysis, such as geological modeling or underground utilities, a local scene is essential since it offers more flexibility in setting ground elevations and working with non-earth-based data like boreholes or tunnel networks.

Tips for Local Scenes

Use custom basemaps: If working on a localized area, using high-resolution imagery or custom basemaps can provide more relevant context compared to global scenes.
Clip to extent: If you are dealing with a very focused area, use the clipping tools to limit the visible extent of your data, which can boost performance and render details faster.
Set a realistic ground elevation: For smaller projects, make sure to set accurate elevation surfaces to reflect real-world topography. If necessary, use higher-resolution elevation models for better detail.

Key differences between Global and Local Scenes

Coordinate system: Global scenes are fixed to a geographic coordinate system (WGS 1984), while local scenes allow you to choose from any geographic or projected coordinate system.
Earth curvature: A global scene accounts for the Earth's curvature, while a local scene assumes a flat surface.
Use case: Global scenes are for large areas (e.g., continents, oceans), whereas local scenes are suited for smaller, more focused regions (e.g., neighborhoods, building models).

Final Tips

Start with the right scale: Before starting a new project, determine whether your data will be covering a global extent or a local region to choose the appropriate scene type.
Combine scenes for analysis: You can use both global and local scenes within the same project to switch between different perspectives based on your task at hand.
Consider performance: Always balance the detail of your data with performance optimization, especially for large scenes that span continents or detailed local scenes with complex 3D features.

Using the right scene type in ArcGIS Pro will make your 3D visualizations more effective and help you to better manage performance and accuracy for your spatial analysis.

Resource(s):

https://pro.arcgis.com/en/pro-app/latest/help/mapping/map-authoring/scenes.htm

https://doc.arcgis.com/en/arcgis-online/create-maps/choose-global-local-scene.htm

https://enterprise.arcgis.com/en/portal/10.4/use/choose-global-local-scene.htm

https://developers.arcgis.com/documentation/mapping-and-location-services/data-visualization/3d-visualization/globes-and-local-scenes/

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