Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Infrared Emission by Fine Water Aerosols and Fogs

Not Accessible

Your library or personal account may give you access

Abstract

Water aerosols, even when so finely divided as to be invisible, are capable of very strong absorption and emission in the infrared. This effect is pronounced in the 8–13-μ atmospheric window, owing to the 104 increase in the absorptivity of liquid water there over that for water vapor, and it contributes to the well known continuum in this spectral region. Water aerosol is found wherever suitable condensation nuclei exist and the relative humidity is above about 60%. Aerosol droplets increase in size and number with increasing relative humidity, affecting atmospheric radiance measurements accordingly. Trace quantities of aerosol can easily account for emission levels exceeding those of water vapor at 8–13 μ and are clearly indicated in cases where observed radiance levels cannot be accounted for by classical vapor band wing absorption theories. The aerosol emission mechanism is not associated with the formation or growth of the water droplets per se, but simply operates when droplets exist in the airborne state. Fog measurements are discussed and curves presented showing attenuation ratios between wavelengths in the visible and at 8–13 μ. Steam emission measurements leading to the formulation of an aerosol emission model are described briefly.

© 1970 Optical Society of America

Full Article  |  PDF Article
More Like This
Model for Infrared Emission of Water Vapor/Aerosol Mixtures

H. R. Carlon
Appl. Opt. 10(10) 2297-2303 (1971)

Infrared extinction spectra of some common liquid aerosols

Hugh R. Carlon, David H. Anderson, Merrill E. Milham, Theodore L. Tarnove, Robert H. Frickel, and I. Sindoni
Appl. Opt. 16(6) 1598-1605 (1977)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (6)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved