WNA-FLEXPART-BackTraj-2015: 2015 Western North America Air Mass Back Trajectories

WNA-FLEXPART-BackTraj-2015 is a 2015 Western North America Back Trajectory dataset produced by NASA using the FLEXPART dispersion model. It provides 15-day backward simulations of air mass transport at hourly and 1° x 1° resolution from the surface to 20 km altitude, designed to match gridded ozone observations from 1994-2021. The dataset supports analysis of source contributions to atmospheric components observed over Western North America across diurnal, seasonal, and decadal timescales.

Use Cases

• Identifying source regions contributing to high ozone levels in Western North America based on backward trajectory simulations.
• Analyzing seasonal and decadal trends in atmospheric transport patterns over a nearly three-decade period.
• Supporting source contribution analyses for other atmospheric components co-located with the defined ozone receptor sites.
• Illustrating source-receptor relationships at different vertical layers from the surface to the upper troposphere.

Strengths

• Provides high-resolution global simulations with hourly temporal and 1° x 1° spatial resolution.
• Covers a long observational period, with receptor locations matched to ozone data from 1994 to 2021.
• Simulations extend from the surface up to 20 km altitude, covering the full tropospheric column.
• Generated with NASA HEC support, indicating high-performance computing resources were used.

Limitations

• Column names and exact data structure are not provided in the available metadata.
• Conflicting 'last updated' dates exist between platforms (2015-12 31 vs. 2026-04-09), creating uncertainty about data currency.
• Dataset size and row counts are unknown, limiting assessment of computational requirements.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

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

Time Range

1994-2021 (for matched ozone observations); simulation year is 2015.

Freshness

2026-04-09 20:39:07.839709 (most recent update across platforms, though conflicting with an earlier date)

Geography

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