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by soperj 2856 days ago
It's almost as if this has happened before... But no, it's record breaking drought.
4 comments

The associated study claims that these stones have been seen many times - they are likely to appear about five times per century. The study points out that the causes of droughts have changed. Previous droughts were largely due to a lack of precipitation. The current levels of precipitation is actually as high as it has even been.

The cause of the current drought is record levels of heat. Despite statistically high levels of rain fall, the temperature of the region is so high that the rivers are drying up anyway.

Not entirely true, at least locally. Precipitation in Czech republic in August is just 40% of normal state for this month [1]. The lack of rains is a big deal here.

[1]: Report about draught from Czech meteorological agency, http://www.chmi.cz/files/portal/docs/tiskove_zpravy/2018/TZ_...

I was summarizing the source document for this article, which is actually a few years old at present.
What you are saying is not greatly removed from “well if the world’s gettin’ so dang warm, why’s it so cold right now?”

Climate science is much more complex than isolated data points such as a local temperature or river level, and to counter multivariate studies with anecdotal reductionism is the tool of demagogues.

It … can be both?!

And given that the stones explicitly warn of catastrophe associated with the drought it doesn’t seem like a too common occurrence.

(Also, on an unrelated note, it’s important not to confuse drought (for which there’s precedence) with global warming and recent heat waves (for which there isn’t precedence). The two are probably connected but they’re not the same.)

How can it have happened before and be record breaking?

Why the unrelated note? Why assume I am an idiot?

“Record” refers to past data. “Record breaking” means you’ve exceeded the past data, not that you’ve exceeded anything that has ever happened.

For example, regular and reliable temperature records only go back to the late 1800s, so any “record breaking” temperature just means it hasn’t happened since 1888 or whatever.

Would you include these stones as data? They're certainly a record of low water levels.
A "record" has multiple shades of meaning. For example, temperature records must be officially observed, using (sufficiently) modern weather instrumentation. That's why https://en.wikipedia.org/wiki/List_of_weather_records says "remotely sensed observations such as satellite measurements, since those values are not considered official records."

This thread spun off into pedantry when you used the phrase "record breaking drought".

I know that there have been record breaking temperatures. https://en.wikipedia.org/wiki/2018_European_heat_wave comments that in Germany "Both April and May set new temperature records as the warmest April and May since modern record-keeping began in 1881."

Note the 'modern record-keeping' associated with 'new temperature records', and that those records are only 150 years old.

It's certainly true that there are older weather records. 10.1023/A:1005505113244 describes weather journals including one which covers the drought of 1540, which was "the most outstanding" one of the last half of the 1000s. 10.1007/s10584-014-1184-2 is "Based on more than 300 first-hand documentary weather report sources" from that time, to describe the 11-month-long Megadrought of 1540.

So, who are you quoting when you use the phrase 'record breaking drought', and what definition are they using?

>So, who are you quoting when you use the phrase 'record breaking drought'

Quoting the article on which this comment is being made.

No, they are not the record being referred to here.
Clearly not. When you just dismiss any records that are below the current drought, then all droughts can become record breaking.
> Why the unrelated note?

I’m calling it “unrelated” because I’m giving you the benefit of doubt — in other words, I don’t assume you’re an idiot. But, on the other hand, this is a fairly common confusion that was repeatedly made by the press and otherwise informed people over the course of the summer. So it’s not that unrelated. (And just to clarify, those people still aren’t idiots. But they’re wrong.)

Um, the fact that the last time it was this bad was 400 years ago is pretty much the definition of "record breaking".
uhhh... the fact that there was a time that was "this bad", means that at most it's record equaling.
The fact that it hasn't been this bad in 400 years suggests that it's a capital-B Big problem though.
We will only see the comet lovejoy every 622 years, that doesn't suggest it's a problem at all, let alone a big one. The fact that the water levels are very low suggest there's a big problem, that we haven't seen them this low in 400 years suggests only that we've seen them this low before and that the world has survived that.
The planet isn't going to die if we irradiate ourselves into caves, but that doesn't mean irradiating the surface of the planet for shits and giggles is a good idea.
And this applies how?
I think it depends on when the record keeping of the event began. So in this case if they started keeping records 250 years ago and they haven't experienced this level of drought since then, then it is considered record breaking. It doesn't mean that there haven't been worse droughts say, 300 or 400 years ago. It just means that either the official record keeping doesn't go that far, or that there may not be scientific research available to show that worse drought did occur before the the record keeping began.
I get that. But clearly there are records there, records etched into stone in fact, that show that these events have occurred previously. That everyone turns this point into climate change denial is ridiculous.