The first article, published in Der Pragmaticus talks about how artificial modifications of cirrus clouds may cool the climate. Cirrus clouds have a warming effect on climate; a decrease in their thickness or frequency may therefore lead to a climate cooling effect.
The second article, published in Der Standard, describes how an artificial aerosol layer in the stratosphere could reflect enough radiation to cool the climate, but involves potentially dangerous side effects. This method, also known as stratospheric sulphur injections, is the most discussed and most controversial of the solar geoengineering ideas.
