VAP : AERI Noise Filtered (AERINF)

Instrument Categories
Radiometric

The ARM Facility is in the process of improving the temporal resolution of the AERI to collect a sky spectrum every 15-30 seconds. The increased temporal resolution results in less averaging performed by the instrument, and hence the larger component of random noise in the sky spectra. This VAP uses the high correlation in the observed radiance across the spectrum to reduce the uncorrelated random error in the data using principal component analysis (PCA). The VAP automatically determines the appropriate number of principal components to use in the reconstruction to eliminate as much random noise as possible. A significant reduction in the uncorrelated random error in the data has been proven for both regular temporal data and rapid-sample data.

For more details, see A Principal Component Analysis Noise Filter Value-Added Procedure to Remove Uncorrelated Noise from Atmospheric Emitted Radiance Interferometer (AERI) Observations.

Output Products

aerich1nf1turn : AERI ch. 1 radiance data, with uncorrelated random error (noise) filtered out
aerich2nf1turn : AERI ch. 2 radiance data, with uncorrelated random error (noise) filtered out

Primary Measurements

The following measurements are those considered scientifically relevant.

Longwave spectral radiance

Locations

North Slope Alaska (NSA)
- Central Facility, Barrow AK (C1)
Southern Great Plains (SGP)
- Central Facility, Lamont, OK (C1)
Tropical Western Pacific (TWP)
- Central Facility, Darwin, Australia (C3)
- Central Facility, Nauru Island (C2)
ARM Mobile Facility (PGH)
- ARIES Observatory, Nainital, Uttarkhand, India (M1)