Seattle now has summers, for one.

https://www.climate.gov/news-features/understanding-climate/...

Are you a vault dweller?

See my other comment above.

No citation is needed when you see the changes with your own eyes, which happened at least in Europe, where I live.

Average temperatures keep going up. That's not binary/state-transition change but it's measurable.

this is not unsupported anecdote

It’s rude to demand a citation when you’ve pre-committed to disbelieving it.