Invisible Volatilization - Methyl Chloride and Ozone Layer Memory

Invisible Volatilization - Methyl Chloride and Ozone Layer Memory

1970s-1990s: The Poison of Silence

Methyl chloride (chloromethane) was once a chemical substance that continued to be quietly used behind the scenes of people's lives. It existed in the shadows of everyday life as a solvent in chemical plants and as a fumigant in agriculture. From the 1970s to the 1990s, the world was so preoccupied with the threat of chlorofluorocarbons (CFCs) and chlorofluorocarbons (CFC) that it did not pay attention to the true nature of methyl chloride.

The 2000s: The Warning of an Awakening Earth

In 2000, a study by the National Institute for Environmental Studies (NIES) revealed that the source of methyl chloride was not just in industrial areas, but also in the natural environment of tropical forests and coastlines [NIES]. Chlorine ions in seawater act on land plants and dead leaves, releasing invisible toxins into the atmosphere. Emissions uncontrolled by mankind have been affecting the skies beyond the skies for many years.

In September of the same year, the Japan Meteorological Agency discovered an ozone hole of unprecedented scale, with ozone depletion over Antarctica reaching 96.22 million tons. The area covered 29.18 million square kilometers, more than twice the size of Antarctica, surpassing the record set in 1998 [Japan Meteorological Agency]. The situation was supposed to be improving due to CFC regulations. Nevertheless, the wounds in the stratosphere did not heal, but continued to cast a new shadow.

2020s: Confronting the Invisible Shadow

In the 2020s, methyl chloride emissions in Japan are reported to be 232 tons per year. From the chimneys of chemical plants and from the corners of production lines, this fine gas is released unnoticed. They do not just disappear into the sky. An invisible force carries it high into the sky, and someday, somewhere, it becomes a visible impact [Ministry of Economy, Trade and Industry].

At the same time, the trend of natural sources has become uncertain. How will the decline of tropical forests and climate change affect the release of methyl chloride? Scientists continue to search for answers as they stare into the rift in the sky [Ministry of the Environment].

Methyl chloride is not regulated by the Montreal Protocol. But how much of its unmarked presence will leave a mark on the future? The day may not be far off when the ozone layer will tell the whole story.

Sources:
- Ministry of the Environment
- National Institute for Environmental Studies
- Ministry of Economy, Trade and Industry
- Japan Meteorological Agency