Business is the activity of making one's living or making money by producing or buying and selling goods or services. Simply put, it is "any activity or enterprise entered into for profit. It does not mean it is a company, a corporation, partnership, or have any such formal organization, but it can range from a street peddler to General Motors." The term is also often used colloquially (but not by lawyers or public officials) to refer to a company, but this article will not deal with that sense of the word.
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.