as very good ice nuclei in colder parts of the atmosphere. The number and type of CCNs can affect the lifetimes and radiative properties of cloud s as well as the amount and hence have an influence on climate change [http://www.agu.org/revgeophys/rasmus00/node26.html] [http://www.grida.no/climate/ipcc_tar/wg1/181.htm]; the details of this are still not well understood