POAM3: Polar Atmospheric Profiles from Solar Occultation

POAM III measures solar extinction in nine spectral channels from 354 to 1018 nm, providing vertical profiles of ozone, water vapor, nitrogen dioxide, and aerosol extinction. The instrument, launched aboard the French SPOT-4 satellite in March 1998, collects data at approximately 101-minute intervals, with sunrise measurements from 55-71°N and sunset measurements from 63-88°S. Each data granule contains one month of hemispheric data, with latitude ranges of 54.68–71.01°N and -62.55 to -88.11°S.

Use Cases

• Tracking polar ozone depletion based on vertical ozone concentration profiles.
• Studying aerosol transport and extinction in polar regions using 442 nm and 1018 nm aerosol data.
• Analyzing atmospheric water vapor and nitrogen dioxide (NO2) trends in the Arctic and Antarctic.
• Validating climate models with high-latitude atmospheric composition data from solar occultation.

Strengths

• Provides long-term data from a mission launched in March 1998, offering a multi-year time series.
• Uses the precise solar occultation technique, measuring atmospheric extinction across nine narrow spectral bands.
• Covers specific, consistent polar latitude bands (55-71°N and 63-88°S) for systematic hemispheric comparison.

Limitations

• Metadata completeness is low; specific column names, row counts, and file sizes are not provided on any platform.
• Conflicting 'last updated' dates exist (2005-12-05 vs. 2026-04-09), creating uncertainty about data currency.
• Spatial coverage is limited to high-latitude polar regions, excluding mid-latitudes and tropics.

Provenance

Source

Naval Research Laboratory (NRL), launched on the French SPOT-4 satellite.

Collection Method

Solar occultation measurements from a sun-synchronous polar orbit.

Time Range

Data collection began in March 1998; specific end date is not provided.

Freshness

2026-04-09 23:10:53.673263

Geography

Northern Hemisphere: 54.68 to 71.01° latitude. Southern Hemisphere: -62.55 to -88.11° latitude. Longitude: 0 to 360°.