Western North America Back Trajectory Data for Ozone Source Analysis

1994-2021 hourly backward trajectory simulations model airmass transport to receptor sites across Western North America. The dataset uses the FLEXPART Lagrangian particle dispersion model driven by ERA5 reanalysis to calculate 15-day source-receptor relationships at 1° x 1° spatial resolution from the surface to 20 km altitude. This product was generated by NASA's Atmospheric Composition Campaign Data Analysis and Modeling program with support from NASA High-End Computing.

Use Cases

• Analyzing source contributions to tropospheric ozone observations at different vertical layers using the gridded ozone value product for each receptor.
• Identifying regional and seasonal patterns in atmospheric transport over nearly three decades via diurnal, daily, and seasonal temporal scales.
• Supporting source contribution analysis for other co-located atmospheric components observed at the same spatial and temporal scales as the ozone receptors.
• Establishing source-receptor relationships (SRRs) for downwind observations from various geospatial regions and atmospheric layers.

Strengths

• Provides nearly three decades (1994-2021) of continuous hourly simulation data for long-term trend analysis.
• Offers high-resolution global simulations with 1° x 1° spatial and hourly temporal granularity.
• Covers a significant vertical range from the surface up to 20 km above ground level.
• Generated using the established FLEXPART model driven by the authoritative ERA5 reanalysis dataset.

Limitations

• Conflicting metadata: one source lists a last update date of 2007-12-31, while others indicate 2026-03-12, creating uncertainty about data currency.
• Specific column names, row counts, and dataset size are not provided by any source platform.
• License is ambiguously listed as 'other-license-specified' without detailed terms.

Provenance

Source

NASA's Atmospheric Composition Campaign Data Analysis and Modeling program, NASA Advanced Supercomputing (NAS) Division at Ames Research Center.

Collection Method

Backward simulations using the FLEXPART Lagrangian Particle Dispersion Model (LPDM) driven by ERA5 reanalysis data.

Time Range

1994-2021

Freshness

2026-03-12 19:50:32.930214

Geography

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