I find it distressing that a man of the stature of Thomas F. Malone (The Environmental Context, July EOS) cites, without qualification, the following to be a result of conscious human actions: ‘The increasing particulate load in the atmosphere which has an effect on the climate that would appear to be opposite to the one produced by an increase in the carbon dioxide content.’

He is doing a disservice to himself, to humanity, and to science to blithely lend his reputation to the validity of a condition of such serious consequences and so poorly substantiated by the available data.