The entire thesis of once in 300 years or once in 1000 years or once in 100 years weather event really has to be let go by the media. The fact is these things are happening or more and more often and are a direct result of climate change and then not once in 300 years, they’re happening all the time
It's also a bad statistical method because if there are 300 cities/regions in the world and a storm hits a random one of them most severely each time, on average you will expect to have one city/region every year seeing a 300-year storm even in a static climate.
Not that I think the climate isn't changing, but because if the headlines are obviously p-hacking all the time you get all climate change reporting eventually called fake news even when it isn't.
I think these terms state how likely some event is for some climate, which is useful for people who don't live in that climate. It isn't so much used for real statistic.
The article says it's the heaviest rainfall recorded in Hat Yai over the last 300 years. So that's the actual meaning, and interpreting it in the probabilistic sense seems to have been the initiative of the headline writer.
This is a severity scale primed with how much likely it was in the past. We might adjust that scale in a century, but the events severity don't change and it would be useless to continuously adjust a scale, while trying to use it, that would make it meaningless.
I mean, we’re still working on convincing people that climate change is actually happening, so if they want to keep reporting the 100yr storms that happen every year now, that’s fine by me.
There is a huge difference between "once per location per 100yr" and "once per 100yr".
Every year there is at least one hurricane Katrina equivalent storm in the world. Having one in New Orleans is once in hundreds of years. Anywhere on the gulf coast is once in, IDK, a dozen.
So you can pretty easily lie and mislead (accidentally or not the results are the same) by not being super careful about scope.
