• sulfur
  • Chlorofluorocarbons (CFC) were developed by the American engineer Thomas Midgley in 1928 as a replacement for ammonia (NH chloromethane (CH Cl), and sulfur dioxide (SO), toxic but in common use at the time as refrigerants . (factbites.com)
  • estimates
  • Of the 682 million kilograms of chlorofluorocarbons consumed globally during 1991, the DuPont Corporation estimates the use for various applications as follows: 32 percent for refrigerants , 28 percent for blowing agents, 20 percent for cleaning agents, and 18 percent for propellants. (factbites.com)
  • comes
  • From the "it's that Methane and Ozone Emergency again" department, comes this breathless headline, for a kitchen sink press release that even includes the obligatory faux sinking atoll of Tuvalu. (wattsupwiththat.com)
  • human
  • To a lesser extent, the clearing of land for agriculture, industry, and other human activities have increased the concentrations of other greenhouse gases like methane (CH4), and further increased (CO2). (nasa.gov)