Politics (from Greek: πολιτικά, translit. Politiká, meaning "affairs of the cities") is the process of making decisions that apply to members of a group.
Factions among yourselves; preferring such To offices and honors, as ne'er read The elements of saving policy; But deeply skilled in all the principles That usher to destruction.
Philip Massinger, The Bondman, Act I, scene 3, line
To understand changes observed in the aerosol layer of the stratosphere, scientists use remote sensing to collect relevant data. EU funded scientists are now 4D modelling aerosol formation and transport, in particular after volcanic eruptions.