HIRDLS/Aura Ozone Zonal Fourier Coefficients for 3-Year Mission

HIRDLS/Aura Level 3 ozone data expresses the entire 3-year mission as zonal Fourier coefficients. Coefficients are computed from Level 2 profiles using a Kalman filter approach, allowing reconstruction of ozone values at any longitude. The data product is provided by NASA on a pressure grid with 121 levels from 422 to 0.1 hPa.

Use Cases

• Model global ozone distribution based on zonal Fourier coefficients
• Analyze ozone variability across latitude bands based on 1-degree resolution
• Study vertical ozone profiles based on data at 121 pressure levels
• Compare daytime and nighttime ozone patterns based on ascending/descending orbit data
• Validate atmospheric chemistry models based on Kalman-filter-derived coefficients

Strengths

• Coefficients cover the entire mission (~3 years) of HIRDLS data
• Data has high vertical resolution with 121 pressure levels from 422 to 0.1 hPa
• Includes separate data fields for ascending (daytime), descending (nighttime), and combined orbit nodes

Limitations

• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Coefficients computed from HIRDLS Level 2 profiles with a Kalman filter approach using forward and backward passes in time.

Time Range

The entire mission (~3 years)

Freshness

Last updated 2026-03-13 01:28:38.153180; freshness should be verified

Geography

Zonal coverage from -64 to 80 degrees latitude