Nov 29, 2023 06:16 PM
(This post was last modified: Nov 29, 2023 06:17 PM by C C.)
https://undark.org/2023/11/28/china-hfc-23/
INTRO: Preliminary atmospheric monitoring data from a remote South Korean island off China’s east coast shows elevated concentrations of hydrofluorocarbon-23, or HFC-23, a greenhouse gas 14,700 times more potent than carbon dioxide on a pound-for-pound basis, according to the World Meteorological Association.
The gas concentrations remain elevated in air samples collected at the Gosan atmospheric monitoring station on South Korea’s Jeju Island in 2022 even after China, previously identified as the source of HFC-23 pollution detected at this site, was supposed to have ceased emitting it under an international agreement.
In June 2021, China ratified the Kigali Amendment to the Montreal Protocol, a binding international agreement that seeks to curb emissions of climate-warming HFCs, synthetic gases primarily used for air conditioning and refrigerating. The agreement entered into force in China on September 15, 2021, requiring the country to reduce HFC-23 emissions “to the extent practicable” by the end of 2021.
The primary source of HFC-23 emissions in China was as a byproduct in the manufacturing of hydrochlorofluorocarbon-22, which is used to produce other fluorinated chemicals including polytetrafluoroethylene, or Teflon. More than half of all HCFC-22 has been produced in China since 2009, according to a United Nations Environment Programme report.
To comply with the Montreal Protocol, HCFC-22 manufacturers must install mitigation technologies, at relatively low cost, to destroy the byproduct HFC-23.
However, air samples collected at Gosan contained elevated concentrations of HFC-23, with some measurements roughly twice that of global background levels measured at other remote locations. The elevated concentrations continued through June 2022, the most recent month for which data is available.
The preliminary data from Gosan suggests there were likely significant emissions of HFC-23 that continued to be released from somewhere in the region throughout the sampling period.
The data, which relies on monitoring equipment capable of measuring trace volumes of pollution down to the parts-per-trillion level, is posted on the website of the Advanced Global Atmospheric Gases Experiment, or AGAGE, a publicly funded international atmospheric monitoring network. AGAGE is sponsored by NASA and other federal agencies including the National Research Foundation of Korea.
The volume and source of emissions that led to the elevated concentrations of the climate pollutant remain unknown. However, a study published in August in the journal Atmospheric Chemistry and Physics concluded that similarly elevated HFC-23 concentrations detected at the same monitoring station from 2008 to 2019 came almost exclusively from eastern China. Ninety-four percent of emissions in East Asia in 2019 could be traced back to eastern China, the study concluded.
HFC-23 emissions from eastern China in 2019 equaled nearly 10,420 tons, according to the study, which was equal to the annual greenhouse gas emissions of 31 million cars or 37 coal fired power plants, according to the EPA’s greenhouse gas equivalency calculator.
Yuan Liu, the director of the Montreal Protocol division for the Foreign Environmental Cooperation Center of China’s Ministry of Ecology and Environment, said the ministry is looking into the issue... (MORE - details)
INTRO: Preliminary atmospheric monitoring data from a remote South Korean island off China’s east coast shows elevated concentrations of hydrofluorocarbon-23, or HFC-23, a greenhouse gas 14,700 times more potent than carbon dioxide on a pound-for-pound basis, according to the World Meteorological Association.
The gas concentrations remain elevated in air samples collected at the Gosan atmospheric monitoring station on South Korea’s Jeju Island in 2022 even after China, previously identified as the source of HFC-23 pollution detected at this site, was supposed to have ceased emitting it under an international agreement.
In June 2021, China ratified the Kigali Amendment to the Montreal Protocol, a binding international agreement that seeks to curb emissions of climate-warming HFCs, synthetic gases primarily used for air conditioning and refrigerating. The agreement entered into force in China on September 15, 2021, requiring the country to reduce HFC-23 emissions “to the extent practicable” by the end of 2021.
The primary source of HFC-23 emissions in China was as a byproduct in the manufacturing of hydrochlorofluorocarbon-22, which is used to produce other fluorinated chemicals including polytetrafluoroethylene, or Teflon. More than half of all HCFC-22 has been produced in China since 2009, according to a United Nations Environment Programme report.
To comply with the Montreal Protocol, HCFC-22 manufacturers must install mitigation technologies, at relatively low cost, to destroy the byproduct HFC-23.
However, air samples collected at Gosan contained elevated concentrations of HFC-23, with some measurements roughly twice that of global background levels measured at other remote locations. The elevated concentrations continued through June 2022, the most recent month for which data is available.
The preliminary data from Gosan suggests there were likely significant emissions of HFC-23 that continued to be released from somewhere in the region throughout the sampling period.
The data, which relies on monitoring equipment capable of measuring trace volumes of pollution down to the parts-per-trillion level, is posted on the website of the Advanced Global Atmospheric Gases Experiment, or AGAGE, a publicly funded international atmospheric monitoring network. AGAGE is sponsored by NASA and other federal agencies including the National Research Foundation of Korea.
The volume and source of emissions that led to the elevated concentrations of the climate pollutant remain unknown. However, a study published in August in the journal Atmospheric Chemistry and Physics concluded that similarly elevated HFC-23 concentrations detected at the same monitoring station from 2008 to 2019 came almost exclusively from eastern China. Ninety-four percent of emissions in East Asia in 2019 could be traced back to eastern China, the study concluded.
HFC-23 emissions from eastern China in 2019 equaled nearly 10,420 tons, according to the study, which was equal to the annual greenhouse gas emissions of 31 million cars or 37 coal fired power plants, according to the EPA’s greenhouse gas equivalency calculator.
Yuan Liu, the director of the Montreal Protocol division for the Foreign Environmental Cooperation Center of China’s Ministry of Ecology and Environment, said the ministry is looking into the issue... (MORE - details)