[HN Gopher] Using grape harvest dates to estimate summer tempera...
___________________________________________________________________
Using grape harvest dates to estimate summer temperature over 650
years
Author : guerby
Score : 72 points
Date : 2022-08-04 19:38 UTC (3 hours ago)
(HTM) web link (tamino.wordpress.com)
(TXT) w3m dump (tamino.wordpress.com)
| greggeter wrote:
| karol wrote:
| Good stuff. Still it's worth to look at the the ice core data
| from Greenland drilling.
| boomchinolo78 wrote:
| Would better weather forecasting move the relationship between
| weather and GHD?
| a9h74j wrote:
| Great move in the article to show shifting _distributions_ , not
| only a plot vs time of a shifting average etc.
|
| Possible confound not discussed: Have there been any changes in
| market or transportation or harvesting-technology or labor
| factors which would affect decisions about "harvest date" ? Were
| any new varieties systematically planted with/after X apparent
| breakpoint? Have _direct_ effects, if any, of increasing CO2 been
| removed?
| moultano wrote:
| Very similar chart to this one recording the date of Japan's
| cherry blossoms blooming since 600 AD.
| https://www.washingtonpost.com/weather/2021/03/29/japan-kyot...
| doitLP wrote:
| Wow very similar graphs
| h2odragon wrote:
| Grapes feature at the end: "we can estimate" followed by a graph
| with a temperature axis. Would like to see the data and the
| formula for turning it to temperature used.
| taneliv wrote:
| Regarding your desire for data, a research article referenced
| on the page: https://cp.copernicus.org/articles/15/1485/2019/
| has a section on "Data availability," which seems to be
| relevant. Possibly the article altogether is interesting to
| you, I didn't read it (yet).
| h2odragon wrote:
| Thanks much!
| anigbrowl wrote:
| _Those dates are on record, and if we use them as proxy data to
| predict the summer average temperature, it does a remarkably
| good job, explaining 60% of the variance of the temperature
| data:_
| legitster wrote:
| An impressive data fit. It's a bummer we don't have data going
| even older - the medieval warm period was between 950 to 1250. It
| would be an interesting comparison point.
| octonion wrote:
| We do -
| https://www.washingtonpost.com/weather/2021/03/29/japan-kyot...
|
| Same result.
| octonion wrote:
| guerby wrote:
| "Now the interesting part: the record of grape harvest date (GHD)
| in Beaune, France goes back to the year 1354. If we use the grape
| harvest dates to estimate summer temperature, and use outbursts
| of extremely hot summer as indicators of extreme summer heat, we
| can estimate it going back over 650 years:"
| missedthecue wrote:
| I wonder if they should account for evolutionary adaptions in the
| grape plants. This article doesn't seem to touch on that but it
| seems like a species of plant could change a _lot_ over 650
| years!
| readthenotes1 wrote:
| Like the watermelon https://images.app.goo.gl/8miHX48hfcHZ3rGQ7
|
| Or the chicken
|
| https://www.vox.com/xpress/2014/10/2/6875031/chickens-breedi...
| throwawaymaths wrote:
| Nah, that's just a watermelon at a different stage of
| ripeness. (I eat like five or six watermelons a year) I've
| gotten one like that, it's rare because we know how to pick
| em these days.
| Buttons840 wrote:
| Wouldn't that be like me painting a bowl of fruit (a common
| thing to practice painting) full of green oranges and green
| bananas? Why did this renaissance painter decide to paint
| an unripened fruit cut and prepared for eating?
| thfuran wrote:
| I don't know, why did Dali paint melted clocks?
| markdown wrote:
| The seeds are dark brown/black, so it's ripe. And you won't
| find a watermelon these days with swirls in it.
| markdown wrote:
| Watermelon is grown from seed, so there can be variation with
| every single generation. Grapes are clones, grown with
| cuttings.
| marginalia_nu wrote:
| If the grape plant changed over 650 years, wouldn't we see a
| drift in the graph over those 650 years? What we're seeing is a
| sudden burst of "evolution" since the 1950s.
|
| Dunno, maybe it's the nuclear tests, but I'm a bit skeptical to
| that explanation.
| buildsjets wrote:
| Evolutionary adaptations? As this is a domesticated plant,
| shouldn't any changes be considered the product of intelligent
| design?
| waserwill wrote:
| Domestication and breeding/husbandry aren't always done
| consciously, but even when they are, people produce selective
| pressures (e.g. selective breeding). Evolution is ambivalent
| to intelligent, conscious choice or natural selection, as
| long as the next generation's heritable traits are different.
| cmrdporcupine wrote:
| Neat. The thing is that people selected for different things in
| grape harvests over different eras. The style of wine for
| Bordeaux "Claret" back in the 17th century for example was a very
| light ruby coloured wine. Now the typical Bordeaux is a very dark
| and extracted product. And consumers in general are often seeking
| out higher alcohol "hotter" wines, partially out of the influence
| of new world wines.
|
| So there could be more compounding factors in grape picking
| dates. Though in general seeking out a darker and higher Brix
| product would mean _later_ picking dates, not earlier.
|
| But grape varieties planted have also changed somewhat overtime,
| too. Not so much in Burgundy where this article is talking about,
| though, so TFA's Beaune is actually a good choice as a point to
| compare.
| quadcore wrote:
| When a lay person, including me, sees those studies, even though
| they are convincing to me, psychologically, there is an after
| taste of "its complicated" which I believe explains why some
| people fall in the deny pool.
|
| Ive realized by experiencing this summer in France, which feels
| like the hottest conditions Ive ever lived in (and Ive lived in
| Thailand and Morocco) that things are actually dead simple. We've
| landed on the moon, we've invented vaccines and smartphones; now
| picture how dead simple this is for us to predict the
| consequences of injecting CO2 in a test tube.
___________________________________________________________________
(page generated 2022-08-04 23:00 UTC)