Western North America Back Trajectory Data for Ozone Source Analysis

NASA's LARC_ASDC provides the WNA-FLEXPART-BackTraj-2012 dataset, featuring backward airmass trajectory simulations for Western North America. The data uses the FLEXPART dispersion model driven by ERA5 reanalysis to calculate 15-day source-receptor relationships at hourly temporal and 1° x 1° spatial resolution, covering altitudes from the surface to 20 km. It supports analysis of ozone source contributions over a period from 1994 to 2021.

Use Cases

• Identifying source regions and atmospheric layers contributing to ozone observations at specific receptor locations.
• Analyzing diurnal, seasonal, or decadal trends in pollutant transport to Western North America.
• Supporting source contribution studies for other atmospheric components co-located with the defined ozone receptor grid.
• Visualizing global 15-day backward trajectories from receptor points up to 20 km altitude.

Strengths

• Covers a long temporal range from 1994 to 2021, enabling multi-decadal analysis.
• Provides high-resolution simulations with hourly temporal and 1° x 1° spatial granularity.
• Integrates multiple observation sources including ozonesonde, lidar, and aircraft campaign data.

Limitations

• Specific row count, file size, and complete column schema are not provided by any source.
• Conflicting 'last updated' dates exist between platforms (2012-12-31 vs. 2026-03-12), creating uncertainty about data currency.

Provenance

Source

NASA LARC_ASDC, supported by NASA’s Atmospheric Composition Campaign Data Analysis and Modeling program and the NASA High-End Computing Program.

Collection Method

Generated using the FLEXPART Lagrangian Particle Dispersion Model driven by ERA5 reanalysis data.

Time Range

1994-2021

Freshness

2026-03-12 19:49:50.881596

Geography

Global simulations with receptor locations focused on Western North America (WNA).