Saunders, RW, Forster, PM and Plane, JMC (2007) Potential climatic effects of meteoric smoke in the Earth's paleo-atmosphere. Geophysical Research Letters, 34 (16). ISSN 0094-8276Full text available as:
Available under licence : See the attached licence file.
Modelling of the growth of meteoric smoke in the Earth's atmosphere, by assuming the formation of either simple spherical ( compact) particles or, more realistically, fractal ( porous) aggregates, highlights important differences in the predicted atmospheric size distributions as a function of altitude. The calculated UV extinction and direct radiative forcing ( DRF) of these types of particles is also quite different. It is shown that, with regard to ( a), forming a UV barrier before the presence of significant ozone levels in the atmosphere and ( b), triggering 'snowball Earth' glaciations by negative DRF, fractal smoke particles are unlikely to have been important even if the flux of interplanetary dust into the atmosphere was 3 orders of magnitude higher than the present day. However, if these particles are effective ice nuclei, then subsequent indirect forcing through ice cloud formation could have made a more significant contribution to the onset of ancient glaciation episodes.
|Copyright, Publisher and Additional Information:||© 2007 American Geophysical Union. Reproduced in accordance with the publisher's self-archiving policy.|
|Keywords:||cosmic dust, stratospheric aerosol, snowball glaciations, ice, mesophere, radiation, particles, chemistry, analogs, cloud|
|Institution:||The University of Leeds|
|Academic Units:||The University of Leeds > Faculty of Maths and Physical Sciences (Leeds) > School of Chemistry (Leeds)
The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds)
|Depositing User:||Symplectic Publications|
|Date Deposited:||13 Oct 2011 12:06|
|Last Modified:||05 Jun 2014 05:24|
|Publisher:||American Geophysical Union|