Aerosol anthropogenic component estimated from satellite data

Satellite instruments do not measure the aerosol chemical composition needed to discriminate anthropogenic from natural aerosol components. However the ability of new satellite instruments to distinguish fine (submicron) from coarse (supermicron) aerosols over the oceans, serves as a signature of th...

Full description

Saved in:
Bibliographic Details
Published in:Geophysical research letters 2005-09, Vol.32 (17), p.L17804.1-n/a
Main Authors: Kaufman, Y. J., Boucher, O., Tanré, D., Chin, M., Remer, L. A., Takemura, T.
Format: Article
Language:English
Subjects:
Aerosols
Assessments
Climate models
Earth sciences
Earth, ocean, space
Estimates
Exact sciences and technology
MODIS
Oceans
Optical thickness
Satellite instruments
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Satellite instruments do not measure the aerosol chemical composition needed to discriminate anthropogenic from natural aerosol components. However the ability of new satellite instruments to distinguish fine (submicron) from coarse (supermicron) aerosols over the oceans, serves as a signature of the anthropogenic component and can be used to estimate the fraction of anthropogenic aerosols with an uncertainty of ±30%. Application to two years of global MODIS data shows that 21 ± 7% of the aerosol optical thickness over the oceans has an anthropogenic origin. We found that three chemical transport models, used for global estimates of the aerosol forcing of climate, calculate a global average anthropogenic optical thickness over the ocean between 0.030 and 0.036, in line with the present MODIS assessment of 0.033. This increases our confidence in model assessments of the aerosol direct forcing of climate. The MODIS estimated aerosol forcing over cloud free oceans is therefore −1.4 ± 0.4 W/m2.
ISSN:0094-8276
1944-8007
DOI:10.1029/2005GL023125