Okay kiddo, have you ever heard of the ozone layer? It's like a big invisible bubble around our planet that protects us from the sun's harmful rays. But sometimes, certain chemicals that people and industries use can damage the ozone layer and make holes in it. This is called ozone depletion.
Now, another thing is that there's something called "tropospheric ozone," which is a type of ozone that exists in the air we breathe. This ozone can be good or bad depending on where it is. When it's up high in the atmosphere, it's good because it's helping to protect us from the sun. But when it's down low in the air we breathe, it's bad for our health.
Sometimes, there are events called "tropospheric ozone depletion events" where there's a lot of this bad ozone in the air. These events usually happen during hot summer days when there's a lot of sunlight and pollution in the air. They can cause problems like coughing, wheezing, and other breathing difficulties.
So, to sum it up, tropospheric ozone depletion events happen when there's too much bad ozone in the air we breathe, and it can make us sick. It's important to try and reduce pollution and use fewer chemicals to help protect the ozone layer and our health.