An unexpected and persistent increase in global emissions of ozone-depleting CFC-11

  title={An unexpected and persistent increase in global emissions of ozone-depleting CFC-11},
  author={S. Montzka and G. Dutton and P. Yu and E. Ray and R. Portmann and J. Daniel and L. Kuijpers and B. Hall and D. Mondeel and C. Siso and J. D. Nance and M. Rigby and A. Manning and Lei Hu and F. Moore and B. Miller and J. Elkins},
The Montreal Protocol was designed to protect the stratospheric ozone layer by enabling reductions in the abundance of ozone-depleting substances such as chlorofluorocarbons (CFCs) in the atmosphere1–3. The reduction in the atmospheric concentration of trichlorofluoromethane (CFC-11) has made the second-largest contribution to the decline in the total atmospheric concentration of ozone-depleting chlorine since the 1990s1. However, CFC-11 still contributes one-quarter of all chlorine reaching… Expand
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A decline in global CFC-11 emissions during 2018-2019.
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