Global atmospheric black carbon inferred from AERONET

Publication Status is "Submitted" Or "In Press: 
LDEO Publication: 
Publication Type: 
Year of Publication: 
2003
Editor: 
Journal Title: 
Proceedings of the National Academy of Sciences of the United States of America
Journal Date: 
May 27
Place Published: 
Tertiary Title: 
Volume: 
100
Issue: 
11
Pages: 
6319-6324
Section / Start page: 
Publisher: 
ISBN Number: 
0027-8424
ISSN Number: 
Edition: 
Short Title: 
Accession Number: 
ISI:000183190700008
LDEO Publication Number: 
Call Number: 
Abstract: 

AERONET, a network of well calibrated sunphotometers, provides data on aerosol optical depth and absorption optical depth at >250 sites around the world. The spectral range of AERONET allows discrimination between constituents that absorb most strongly in the UV region, such as soil dust and organic carbon, and the more ubiquitously absorbing black carbon (BC). AERONET locations, primarily continental, are not representative of the global mean, but they can be used to calibrate global aerosol climatologies produced by tracer transport models. We find that the amount of BC in current climatologies must be increased by a factor of 2-4 to yield best agreement with AERONET, in the approximation in which BC is externally mixed with other aerosols. The inferred climate forcing by BC, regardless of whether it is internally or externally mixed, is approximate to1 W/m(2), most of which is probably anthropogenic. This positive forcing (warming) by BC must substantially counterbalance cooling by anthropogenic reflective aerosols. Thus, especially if reflective aerosols such as sulfates are reduced, it is important to reduce BC to minimize global warming.

Notes: 

684DTTimes Cited:51Cited References Count:29

DOI: 
DOI 10.1073/pnas.0731897100