If the Montreal Protocol was signed in 1987, why is there still a ozone hole?

What is predicted to happen to the ozone hole over the next few decades?

What do you think would be the result of ozone depletion over the Arctic was the same as it is over Antarctica?

1) The ozone layer filters out dangerous ultraviolet radiation from the sun that can cause skin cancer and damage many life forms. ... They had begun creating a dramatic “hole” in the ozone layer at the end of each austral winter. The ensuing panic resulted in the signing of the Montreal Protocol on September 16, 1987.

2) not sure actually but you can say that because of the corona virus it is actually helping to the environment that we can see clear sky. and it is also helping to the world pollution. the word total pollution is decreasing.

3) Ozone depletion over the Antarctic occurs because: Special atmospheric and chemical conditions exist there and nowhere else on the globe. The very low winter temperatures in the Antarctic stratosphere cause polar stratospheric clouds (PSCs) to form.

good one: produce hormones that plants grow.

bad one: the problem with organic matter is that while plant nutrients are needed for crop growth, they can also stimulate excessive growth of the wrong plants – mainly, algae.