HIRDLS Satellite Nitrous Oxide Zonal Fourier Coefficients

HIRDLS/Aura Level 3 Nitrous Oxide (N2O) Zonal Fourier Coefficients V007 contains the entire ~3-year mission of High Resolution Dynamics Limb Sounder data. The GES DISC provides this product, which expresses N2O profiles as zonal Fourier coefficients for latitude bands from -64 to 80 degrees at 121 pressure levels. Data are stored in HDF-EOS5 format, with the last update recorded in March 2008.

Use Cases

• Reconstruct global 3D N2O fields at any longitude using the provided mean and up to 7 sine and cosine Fourier coefficients.
• Analyze vertical profiles of N2O from 100 to 5.1 hPa pressure levels, corresponding to ~1 km resolution, for atmospheric chemistry studies.
• Compare daytime (ascending orbit) and nighttime (descending orbit) N2O distributions using the separate data fields for each orbit node.
• Assess data precision for the estimated fields using the provided root-mean-square difference values against the input Level 2 profiles.
• Study zonal mean atmospheric composition across 1-degree latitude bands from -64 to 80 degrees over the mission's ~3-year time span.

Strengths

• Covers the entire ~3-year HIRDLS mission, providing a complete temporal record.
• Provides data on a detailed grid of 121 pressure levels with about 1 km vertical resolution.
• Coefficients allow for the computation of values at any longitude, enabling global spatial reconstruction.

Limitations

• Temporal coverage ends with the mission, making the data stale for contemporary analysis after 2008.
• Latitudinal coverage is limited from -64 to 80 degrees, excluding the polar regions above 80 degrees.
• Data precision is derived from model estimation (Kalman filter) against input profiles, not direct measurement.

Provenance

Source

GES DISC (Goddard Earth Sciences Data and Information Services Center), NASA.

Collection Method

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

Time Range

Covers the entire HIRDLS mission, approximately 3 years up to 2008.

Freshness

Last updated in March 2008; no ongoing updates.

Geography

Global zonal coverage from -64 to 80 degrees latitude.