Western North America Air Mass Back Trajectory Data for Ozone Analysis

Hourly 15-day backward air mass trajectory simulations for 1994-2021, generated using the FLEXPART Lagrangian dispersion model driven by ERA5 reanalysis data. This dataset provides source-receptor relationships for gridded ozone observations over Western North America, with global coverage at 1° x 1° spatial resolution from the surface to 20 km altitude. It was produced by NASA's Atmospheric Composition Campaign Data Analysis and Modeling program with support from the NASA High-End Computing Program.

Use Cases

• Analyzing source contributions to ozone observations at different vertical layers using the gridded ozone value product per receptor.
• Investigating seasonal or decadal changes in air mass transport patterns over Western North America via the hourly, global trajectory data.
• Supporting source attribution studies for other atmospheric pollutants if observations are co-located with the defined ozone receptor sites.
• Validating or complementing atmospheric dispersion models using the high-resolution (1° x 1°, hourly) FLEXPART simulations driven by ERA5.

Strengths

• Simulations cover a long temporal range from 1994 to 2021, enabling analysis of multi-decadal trends.
• Provides high-resolution global data with hourly temporal and 1° x 1° spatial granularity.
• Model is driven by the authoritative ERA5 reanalysis dataset and calculates detailed 15-day backward trajectories.

Limitations

• Key metadata such as row count, column names, and exact dataset size are not provided on any platform.
• There is a conflict in the 'last updated' date between sources: one states 2019-12-31, while others state 2026-03 12.

Provenance

Source

NASA's Atmospheric Composition Campaign Data Analysis and Modeling program, NASA High-End Computing Program, NASA Advanced Supercomputing Division.

Collection Method

FLEXPART Lagrangian Particle Dispersion Model simulations driven by ERA5 reanalysis, with receptor locations matched to gridded ozone observations from ozonesonde, lidar, and aircraft.

Time Range

1994-2021

Freshness

2026-03-12 19:49:39.963029

Geography

Global simulations with receptor focus over Western North America (WNA), from surface to 20 km altitude.