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irthomasthomas

I thought we where not supposed to conflate weather and climate change?

https://www.nasa.gov/mission_pages/noaa-n/climate/climate_we...

https://www.science20.com/news_articles/stop_conflating_weat...

https://blogs.scientificamerican.com/hot-planet/dont-be-fool...

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It isn't being conflated.

The way this sort of research works is by modeling weather under different conditions and determining that certain weather patterns are statistically more likely under conditions consistent with global warming. This isn't just "it is hot for a week so that must be global warming". It is "the air patterns that are required for this sort of thing to happen are highly associated with higher average global temperatures". The causality is going in the other direction.

The models are useless. Or very useful: you can choose any you like to prove a point.

Which is why, for this type of research, you use an ensemble of multiple competing models, which also helps with extracting probabilities. If you think their methodology is flawed, then have the decency to respect the enormous amount of effort that goes into this kind of research and point out actual, specific flaws.

They won't.

An old friend of mine is a professor who studies climate change. They fairly consistently get hate mail from people who insist that computer modeling as an entire discipline is utterly worthless and should be dismissed without any investigation. There are no reasoned criticisms coming from the denier community.

I respect the research. That's a different thing than having any confidence in the models created. I also do not think that methodology is flawed, but that it does not produce reliable results (yet) because of the enormous complexity involved.

Why do you feel that the people who work on and with these models for their careers have different opinions than you?

Most models point roughly in the same direction. Read the IPCC reports for expert interpretation of the ensembles.

Did you read even one of the articles I linked?

But the BBC article... "the research has not yet been peer-reviewed.

"They used 21 climate models to estimate..."

"They compared the climate as it is today, with the world as it would be without human-induced warming."

This is not empirical science. And by using a 1000 year model they are starting their analysis, conveniently, after the peak of the Roman Warm Period.

> And by using a 1000 year model they are starting their analysis, conveniently, after the peak of the Roman Warm Period.

They don't seem to be using a 1000 year model, they are just saying the rate of occurrence. And when do you think the Romans, and their related warming period, were exactly?

https://www.newscientist.com/article/dn22040-tree-rings-sugg... "How did the Romans manage to grow grapes in northern England when most climate studies suggest the weather was much cooler then? We may now have an answer: it wasn’t that cold at all."

Edit: oops I did mixup the late Roman and Medieval warm periods. Anyway both the RWP around 2000 years ago and the MWP 1000 years ago are what geologists call interglacial periods. The earth is currently in an ice age (when there is permanent ice at either of the poles) but every thousand years or so the climate warms and the ice retreats for a couple hundred years. Unfortunately most climate change studies only consider data from 1850 onwards, and those that do go back further only go start at the last glacial period about a thousand years ago.

I wasn't asking regarding the existence of the period. The Roman Warming period was ~250 BC to ~400 AD - much closer to 2,000 years ago than 1,000. It wasn't anywhere relevant. You're also ignoring that the medieval warming period WAS exactly 1,000 years ago and we're currently beating those temperatures.

Edit to match your edit: Neither the MWP nor the RWP were global phenomenas - they were hotspots at different times for different regions. What we are currently experiencing is a GLOBAL increase.

You are claiming that the last two warm periods where not global? So you deny the existence of the Minoan, Roman, and the Medieval interglacials? I think geologists would disagree.

https://news.climate.columbia.edu/2019/07/24/climate-epochs-...

So you are denying the glacial/interglacial cycle that is taught in geology. I guess that makes you a science denier ;) https://en.wikipedia.org/wiki/Interglacial

Also worth noting this from your article... "During the following Little Ice Age, which lasted roughly from 1300 to 1850"

There's that 1850 again, the climactic minimum, and coincidentally the exact year that climate change models start from.

"1550 to 1850 AD Little Ice Age Coldest temperatures since the beginning of the Holocene. Populations die from crop failure and famine in Europe." http://www.atmo.arizona.edu/students/courselinks/fall12/atmo...

Funny how these ideas are touted until there's an hot summer then all the articles talking about how this _weather_ is a _clear example_ of climate change.

Funny how many times the same thing needs to be explained. At some point one thinks that people making this argument are arguing in bad faith.

> there's an hot summer

Didn't you notice that, lately, every summer is "a hot summer" and "warmer than before"?

> warmer than before

The summers were "getting warmer than before" for the past 400 years, before anthropocentric global warming. Look at any long term trend for temperature. e.g. https://www.ncdc.noaa.gov/global-warming/last-2000-years

These are such weak arguments. It's pretty settled that humans do influence climate. Why do we need to appeal to fallacies when discussing about it?

It’s not the type of weather, it’s the extremity, that’s concerning.

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