Scientists find ozone depletion began decades before discovery of ozone hole

MIT scientists led by atmospheric chemist Susan Solomon conducted a thought experiment asking: if today's atmospheric monitoring tools had existed throughout the 20th century, when would the first signs of human-induced ozone depletion have been detectable? Using 16 climate model runs combined with industrial emissions data and Antarctic ice core records, they found that ozone depletion would have been detectable as early as 1957 — roughly 30 years before the ozone hole was officially discovered in 1985. Surprisingly, this earliest signal appeared not over Antarctica but in the tropical upper stratosphere, where natural variability is lowest. Even more unexpected, the culprit was not CFCs but carbon tetrachloride, a dry-cleaning and degreasing chemical in widespread use from the 1930s. The findings, published in PNAS, underscore the importance of continued atmospheric monitoring even as ozone-depleting substances are phased out.

Nguồn: https://news.mit.edu/2026/scientists-find-ozone-depletion-began-decades-before-ozone-hole-discovery-0629. 8sync News chỉ tóm tắt và dẫn link; bản quyền nội dung thuộc tác giả và nguồn gốc.