Vineyard owners have to keep track of when they harvest their grapes, so that they get them for their wines at the perfect time.
So naturally, they keep very good records of when they harvested the grapes.
And they've done this for centuries.
Thus, another indication of how climate on Earth has changed.
The longest homogeneous series of grape harvest dates, Beaune 1354–2018, and its significance for the understanding of past and present climate
Here's the final sentence of the abstract, but I recommend perusing the full fascinating paper:
"In sum, the 664-year-long Beaune GHD series demonstrates that outstanding hot and dry years in the past were outliers, while they have become the norm since the transition to rapid warming in 1988." [GHD stands for Grape Harvest Dates.]
The link above goes to the actual article: here's the Daily Mail take on it --
Grapes for Burgundy red wines now ripen TWO WEEKS earlier than they did in the 80s as climate change continues to cause soaring global temperatures
"Finally, the team compared the most recent 360 years of their harvest data with detailed temperature record taken in Paris over the same period.
From this, they could estimate Beaune's April–July temperatures across the entire 664 years covered by their grape harvest records.
'The transition to a rapid global warming period after 1988 stands out very clearly,' said Professor Pfister.
'The exceptional character of the last 30 years becomes apparent to everybody."
Everybody, that is, except those who are predisposed to ignore the obvious.