Navigation and service

CM SAF: Aerosol Information

00readme1_txtInformation on data and publication for the global aerosol climatology
PublicationAn AeroCom initial assessment - optical properties in aerosol component modules of global
models
Abstract
The AeroCom exercise diagnoses multi-component aerosol modules in global modeling. In an
initial assessment simulated global distributions for mass and mid-visible aerosol optical thickness
(aot) were compared among 20 different modules. Model diversity was 5 also explored in the
context of previous comparisons. For the component combined aot general agreement has
improved for the annual global mean. At 0.11 to 0.14, simulated aot values are at the lower end of
global averages suggested by remote sensing from ground (AERONET ca. 0.135) and space
(satellite composite ca. 0.15). More detailed comparisons, however, reveal that larger differences
in 10 regional distribution and significant differences in compositional mixture remain. Of particular
concern are large model diversities for contributions by dust and carbonaceous aerosol, because
they lead to significant uncertainty in aerosol absorption (aab). Since aot and aab, both, influence
the aerosol impact on the radiative energy-balance, the aerosol (direct) forcing uncertainty in
modeling is larger than differences in aot 15 might suggest. New diagnostic approaches are
proposed to trace model differences in terms of aerosol processing and transport: These include
the prescription of common input (e.g. amount, size and injection of aerosol component emissions)
and the use of observational capabilities from ground (e.g. measurements networks) or space
(e.g. correlations between aerosol and clouds).
Report as PDFAerosol Direct Radiative Forcing with an AERONET touch
Introduction
Aerosol introduces one of the largest uncertainties in climate research. Aerosol originates from
different sources and has short lifetimes on the order of a few days. Thus, aerosol properties
(characterized by amount, size and composition) and their vertical distribution vary strongly by
location and in time. Complicating factors to assessments of the aerosol impact on climate are
uncertainty and the variability of environmental properties such as clouds and surface properties,
which modulate the aerosol associated impact. The impact of any atmospheric change is
commonly quantified by radiative ...
gamtomeda2angstrom parameter (870-440nm)
gomtomeda2aot, Aerosol optical depth at 550 nm
gwmtomeda2single-scattering-albedo at 550 nm

PF / Jan2014

This Page

© DWD - 2014