Location

University of Utah

Start Date

12-6-1996 10:15 AM

Description

The University of Denver's Absolute Solar Transmittance Interferometer (ASTI) has been developed and employed to radiometrically measure the infrared solar radiance and irradiance at the Earth's surface for several ground-level altitudes ranging from 300 to over 14,000 feet. ASTI also has a major research role in making absolutely calibrated IR measurements of on-axis and off-axis transmittance and scattering properties of numerous cloud types. These measurements and results will provide radiometric information for implementing the IR properties of the atmosphere and cloud IR albedo into General Circulation Models (GCM). The ASTI instrument is described. along with the IR bands available and the radiometric calibration capability using NIST -standard calibrated lamps. The Langley plot technique has been used to conduct initial analyses and to plot the calibrated IR data for several atmospheric paths as a function of solar zenith angle and solar zenith angle. The exoatmospheric intercepts are provided for nine IR lines ranging from 4180 to 7481 cm-1. Initial cloud spectra are provided over the IR band from 4000 to 10000 cm-1 showing interesting properties.

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Jun 12th, 10:15 AM

Measurement of Absolute Solar Infrared Radiation Through the Atmosphere

University of Utah

The University of Denver's Absolute Solar Transmittance Interferometer (ASTI) has been developed and employed to radiometrically measure the infrared solar radiance and irradiance at the Earth's surface for several ground-level altitudes ranging from 300 to over 14,000 feet. ASTI also has a major research role in making absolutely calibrated IR measurements of on-axis and off-axis transmittance and scattering properties of numerous cloud types. These measurements and results will provide radiometric information for implementing the IR properties of the atmosphere and cloud IR albedo into General Circulation Models (GCM). The ASTI instrument is described. along with the IR bands available and the radiometric calibration capability using NIST -standard calibrated lamps. The Langley plot technique has been used to conduct initial analyses and to plot the calibrated IR data for several atmospheric paths as a function of solar zenith angle and solar zenith angle. The exoatmospheric intercepts are provided for nine IR lines ranging from 4180 to 7481 cm-1. Initial cloud spectra are provided over the IR band from 4000 to 10000 cm-1 showing interesting properties.