HIRDLS/Aura Chlorine Nitrate Zonal Fourier Coefficients, 3-Year Mission

A 3-year mission dataset from the HIRDLS instrument on the Aura satellite, providing chlorine nitrate (ClONO2) measurements expressed as zonal Fourier coefficients. The data is processed with a Kalman filter and stored in HDF-EOS5 format, covering latitudes from -64 to 80 degrees at 121 pressure levels. It was produced by NASA and last updated in March 2026.

Use Cases

• Modeling stratospheric chlorine nitrate distribution based on zonal Fourier coefficients.
• Analyzing longitudinal variability of atmospheric constituents based on sine and cosine coefficients.
• Studying diurnal cycles in atmospheric chemistry based on separate ascending (daytime) and descending (nighttime) data fields.
• Investigating vertical profiles of trace gases based on data from 100 to 1.0 hPa pressure levels.

Strengths

• Data covers the entire HIRDLS mission (~3 years), providing a complete temporal record.
• Vertical resolution is about 1 km, with data provided on a pressure grid of 121 levels.
• Coefficients allow computation of values at any longitude, offering full longitudinal reconstruction.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The useful vertical range is limited to 100 to 1.0 hPa.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Coefficients computed from HIRDLS Level 2 profiles with a Kalman filter approach.

Time Range

The entire HIRDLS mission (~3 years).

Freshness

Last updated 2026-03-13 01:39:56.328738; freshness should be verified.

Geography

Zonal coverage from -64 to 80 degrees latitude.