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Spatial Allocator for air quality modeling

What is the Spatial Allocator?

The Spatial Allocator is a set of tools that helps users manipulate and generate data files related to emissions and air quality modeling without requiring the use of a commercial Geographic Information System (GIS). 

What are the benefits of using the Spatial Allocator?

The Spatial Allocator performs functions similar to GIS but is provided to the modeling community free of charge. It is designed to support unique aspects of the file formats used for the Community Multi-scale Air Quality (CMAQ) model, the Sparse Matrix Operator Kernel Emissions (SMOKE) model, and the Weather Research Forecasting (WRF) model. It uses GIS industry standard Environmental Systems Research Institute shapefiles, images supported by the Geospatial Data Abstraction Library, Network Common Data Form, and plain text data files as input and output data.  

Who should use the Spatial Allocator?

SMOKE, WRF and CMAQ users can use the Spatial Allocator tool for model input and output data processing.

How does the Spatial Allocator Work?

The Spatial Allocator manipulates and generates data files related to emissions and air quality monitoring. It uses Linux-based tools developed using open source libraries. There are three components to the Spatial Allocator:

  1. Vector Tools: These tools process vector GIS data to perform functions such as mapping data from counties to grids and vice versa.
  2. Raster Tools: These tools process raster data to perform functions such as converting National Land Cover Database (NLCD) land use data into gridded land use.
  3. Surrogate Tools: These tools use the Vector Tools and additional Java tools to help manage the creation and manipulation of spatial surrogates used in emissions modeling.

Download Now:

The Spatial Allocator is available for download from the Community Modeling and Analysis System (CMAS) website. EPA instituted the CMAS website in 2001 to provide community air quality modeling support, sharing of ideas and techniques through communication, and to encourage the growth of the community. It is currently operated under contract by the University of North Carolina at Chapel Hill’s Institute for the Environment.

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