Pupils in the second and fourth years of secondary school in the Netherlands felt less happy in 2021 than before the coronavirus SARS-CoV-2 pandemic, in 2019.

Lockdowns have a negative impact on the physical and mental health of many young people. They get less exercise and experience more feelings of depression, loneliness and insecurity.

The Montreal Protocol has not only served to protect the ozone layer, it also has provided a certain degree of climate protection.