One cold morning, with a very clear sky, no clouds in sight, I overheard two old ladies discussing how when they were young the sky was bluer, they both agreed. This was in Salamanca, Spain, not Beijing, so no smog to account for.
"Summers are not as they used to be"
and
"there are no autumns and springs anymore"
They were used as examples of empty cliches that old people repeat - something to absolutely avoid. Somehow it was known that while everybody feels that it is so, it's also a form of mis-perception, much like "Nowadays young people have no manners any more". Then the climate change issue became prominent, and immediately everybody was transformed again in its own legitimate one-person weather station, complete with long and accurate temperature records.
In the "Dictionnaire des idées reçues", a long and hilarious list of vacuous cliches that Flaubert compiled in the 1870s, you can read the following line:
"Hiver. Toujours exceptionnel"