Climate change is contributing to higher levels of ground-level ozone despite improvements in air quality, the Swiss Academy of Sciences (SCNAT) said in a report released on Monday, according to Swissinfo.
The academy said increasingly frequent heatwaves, together with hot, sunny, and dry weather, are creating conditions that favor ozone formation near the ground.
Ground-level ozone can irritate the respiratory system, damage plants, and contribute to global warming, unlike the ozone layer in the upper atmosphere, which protects the Earth from harmful ultraviolet radiation.
SCNAT said Switzerland has reduced emissions of ozone-forming pollutants through stricter environmental rules, but ozone limits continue to be exceeded because of complex atmospheric processes and the effects of climate change.
The report also said the recovery of the protective ozone layer remains slow, while emissions of nitrous oxide, an ozone-depleting substance, continue to rise globally due to increased fertilizer use.
According to the academy, Switzerland operates the world's longest continuous ozone monitoring record, which began in 1926 and is now maintained by the Federal Office of Meteorology and Climatology, MeteoSwiss.