ArcGIS Pro Tutorial: Extract Raster Values to Vector Data Using Zonal Statistics As Table In ArcGIS Pro

Extracting raster values to vector data is a fundamental GIS operation that allows analysts to summarize and transfer raster information to polygon boundaries. Zonal Statistics as Table in ArcGIS Pro is one of the most powerful tools for this purpose, enabling users to calculate statistical measures of raster cells within polygon zones.

Understanding Zonal Statistics as Table

The Zonal Statistics as Table tool calculates statistics on values of a raster within the zones of another dataset and reports the results to a table. This tool is particularly useful when you need to:

• Calculate average elevation within administrative boundaries
• Summarize precipitation data for watershed areas
• Extract land use statistics for census tracts
• Analyze temperature patterns across different ecological zones

Step-by-Step Tutorial

Step 1: Prepare Your Data

Before running the tool, ensure your data meets the following requirements:

• Zone data must be in polygon format
• Raster data should be properly projected
• Both datasets should be in the same coordinate system
• Dataset names should not contain spaces or special characters

Step 2: Access the Tool

In ArcGIS Pro, follow these steps to access the Zonal Statistics as Table tool:

1. Open ArcGIS Pro and your project
2. Navigate to the Analysis tab
3. Click on Tools
4. In the Geoprocessing pane, search for “Zonal Statistics as Table”
5. Double-click the tool to open it

Step 3: Configure Tool Parameters

The tool requires several key parameters to be set correctly:

Input Parameters:

• Input zone data: Select your polygon layer that defines the zones
• Zone field: Choose the field that uniquely identifies each zone (typically OBJECTID or FID)
• Input value raster: Select the raster dataset containing values to be summarized
• Output table: Specify the location and name for the output statistics table
• Statistics type: Choose from MEAN, MAJORITY, MAXIMUM, MEDIAN, MINIMUM, MINORITY, RANGE, STD, SUM, or VARIETY
• Ignore NoData in calculations: Check this box to exclude NoData cells from calculations

Step 4: Execute the Tool

After configuring all parameters:

1. Review all parameter settings carefully
2. Click Run to execute the tool
3. Monitor the progress in the Geoprocessing pane
4. Check for any warning or error messages

Step 5: Analyze Results

Once the tool completes successfully:

• The output table will contain statistical values for each zone
• Join the results table back to your original polygon layer using the zone field
• Verify the results make sense for your analysis
• Create maps visualizing the statistical summaries

Advanced Tips and Techniques

Multiple Statistics at Once

For more comprehensive analysis, consider running the tool multiple times with different statistics types or use the “Combine” approach with additional tools like Summary Statistics.

Handling Large Datasets

When working with large datasets:

• Consider creating a file geodatabase for output tables
• Use appropriate data types to optimize storage
• Process data in smaller chunks if memory issues occur
• Ensure sufficient disk space for temporary files

Quality Control Measures

Always verify your results by:

• Checking for unexpected zero or null values
• Comparing results with known values when possible
• Examining the spatial distribution of results on a map
• Reviewing zone counts and distributions

Common Use Cases

Environmental Analysis

Zonal Statistics as Table is widely used in environmental applications:

• Calculating average NDVI values for agricultural fields
• Summarizing soil properties within watershed boundaries
• Analyzing climate data for different ecological zones
• Assessing forest canopy coverage by administrative areas

Urban Planning

Urban planners frequently use this tool for:

• Calculating population density within planning zones
• Summarizing noise levels by neighborhood boundaries
• Analyzing accessibility measures for public services
• Evaluating land use patterns within census tracts

Disaster Management

Emergency management applications include:

• Assessing flood risk levels by administrative boundaries
• Calculating exposure of populations to hazard zones
• Analyzing elevation data for evacuation planning
• Summarizing damage assessments by affected areas

Performance Optimization

Data Preprocessing

Optimize performance by:

• Clipping raster data to the extent of your zones
• Simplifying complex polygon geometries
• Using appropriate raster resolution for your analysis scale
• Ensuring both datasets are in the same projection

Tool Settings

Consider these performance-related settings:

• Use the “Ignore NoData” option to improve processing speed
• Choose appropriate statistics types for your needs
• Process data in logical zones rather than all at once
• Use parallel processing when available

FAQ Section

What is the difference between Zonal Statistics and Zonal Statistics as Table?

Zonal Statistics creates a new raster dataset with the statistical values, while Zonal Statistics as Table creates a standalone table. The Table version is more suitable when you want to perform further analysis or join results back to vector data.

Why am I getting “NoData” values in my results?

NoData values can occur for several reasons: the zone might not overlap with the raster, all raster cells within a zone might be NoData, or there might be projection mismatches. Check your data alignment and NoData settings in both datasets.

Can I use point or line features as zones?

Zonal Statistics as Table requires polygon zones. For point or line features, you need to create buffer zones first or use alternative tools like Extract Values to Points for point features.

How do I handle zones that are very small compared to raster cell size?

Small zones might not contain complete raster cells, leading to inaccurate results. Consider resampling your raster to a finer resolution or aggregating small zones into larger units before analysis.

What statistics types are available in the tool?

The tool supports multiple statistics types including: MEAN, MAJORITY, MAXIMUM, MEDIAN, MINIMUM, MINORITY, RANGE, STD (standard deviation), SUM, and VARIETY (number of unique values).

How can I join the results back to my original polygon layer?

Use the Join Field tool or right-click on your polygon layer in the Contents pane, select Joins and Relates > Add Join, then join using the common zone field that appears in both your polygon layer and the output statistics table.

Why is the tool running very slowly?

Performance issues can stem from large raster datasets, complex polygon geometries, or insufficient system resources. Try clipping data to smaller extents, simplifying polygons, or processing data in smaller chunks.

Can I process multiple rasters at once?

The tool processes one raster at a time. For multiple rasters, you can run the tool multiple times or use ModelBuilder to automate the process. Alternatively, consider using the Combine tool with raster calculator for more complex multi-raster analysis.

What should I do if my zones don’t align properly with the raster?

Ensure both datasets use the same coordinate system. You may need to project one or both datasets. Consider using the Snap Raster environment setting to align raster processing cells properly.

How do I interpret the output table fields?

The output table typically includes: ZONE (the zone identifier), COUNT (number of cells), AREA (total area of cells), and the calculated statistic field (MEAN, MAX, etc.). Additional fields depend on the statistics type selected.