According to preliminary data released by scientists on Monday, emissions of a banned ozone-depleting gas have unexpectedly increased since 2012, but emissions have seen a decline in the past two years.
China was once considered to be the main source of emissions of this chemical CFC-11, and the results of the survey indicate that the country has made great strides in combating the illegal production of CFC-11. CFC-11 is used to make insulating foams.
“The good news is that this morning's report shows that emissions are now dropping significantly,” said Dewood Zha, director of the Institute for Governance and Sustainable Development, a research and advocacy organization based in Washington, DC. Durwood Zaelke said.
“好消息是，今天上午的报告显示，排放量现在显著下降，”位于华盛顿哥伦比亚特区的研究和倡导组织“治理与可持续发展研究所”(Institute for Governance and Sustainable Development)所长德伍德·扎尔克(Durwood Zaelke)说。
The data was submitted by Stephen A. Montzka, a research chemist at the National Oceanic and Atmospheric Administration, at the Montreal Protocol meeting of the Montreal Protocol. The environmental agreement signed in the 1980s is a milestone that bans CFC-11 and similar chemicals collectively known as chlorofluorocarbons.
这些数据是美国国家海洋和大气管理局(National Oceanic and Atmospheric Administration)的研究化学家史蒂芬·A·蒙茨卡(Stephen A. Montzka)在于罗马举行的《蒙特利尔议定书》(Montreal Protocol)缔约国会议上提交的，这份1980年代签署的环境协议具有里程碑意义，它禁止了CFC-11和统称为氯氟碳化合物的类似化学物质。
In 2018, Montezca and colleagues reported that emissions of CFC-11 are rising globally. In the past few years, as new product production was banned, most of the emissions came from the aging of existing foams, CFC- The emissions of 11 are steadily declining. They said that if emissions continue to increase, it will slow the process of ozone layer recovery. The ozone layer protects organisms, including humans, from harmful solar radiation.
Research in 2018 shows that most of the abnormal emissions come from East Asia. Further research this year has found the source more accurately, indicating that at least 40% to 60% of the increased emissions come from eastern China. Several surveys have found evidence that factories in parts of China are producing the gas or using it to make insulating foam, including a survey conducted by the New York Times.
The Montreal Protocol is widely regarded as the most successful environmental convention in history and was drafted after studying how chlorofluorocarbons (which have been widely used as refrigerants and propellants) harm the ozone layer. (Because they are greenhouse gases, they also cause global warming.)
By requiring countries to monitor and phase out the production of these chemicals, the Convention has contributed to an increase in stratospheric ozone, which is expected to be fully restored by the middle of the century.
Zarke said that the new findings show that "the treaty mechanism is continuing to play a role and we are seeing a response."
China initially denied that its factory violated the ban on CFC-11, but the government also promised to ban any illegal production it found. On Wednesday, it submitted a brief report to the meeting on the actions of the Chinese side.
The Chinese government has specifically strengthened monitoring and enforcement, provided equipment to inspectors to immediately discover the existence of CFC-11, and established six regional testing laboratories.
The report also details the removal of several CFC-11 plants, including a factory in Liaoning Province behind the seafood processing facility. However, the three factories described in the report are small in size and cannot meet the level of CFC-11 emissions since 2012.
Zarke said that China’s report shows that to fully understand how abnormal emissions occur and to ensure that similar incidents do not happen again, there is still more work to be done.
China clearly attaches great importance to this issue and has responded well, he said. "But everything didn't end there."