. . "2019-01-14" . . "tendency_of_X means derivative of X with respect to time. Content indicates a quantity per unit area. The atmosphere content of a quantity refers to the vertical integral from the surface to the top of the atmosphere. For the content between specified levels in the atmosphere"@en . . "2019-01-14" . . "tendency of atmosphere mass content of ethers due to emission from residential and commercial combustion"@en . .