[mbostleman]

How do we know this is the result of climate change? It's meant as an honest question. Though it is largely ignored in the mainstream discussion, I've heard for years to be careful about making a distinction between weather and climate. Are you thinking this is not weather, but climate? How does one tell the difference? If there's a record winter of cold temps, would it be evidence that the climate is cooling?

[jbotz]

There are actually scientific methods for attributing specific events to global warming or not, probabilistically. I.e. although you can never say with perfect certainty "this heatwave was caused by global warming", you can say: with global warming this heatwave has a probability 0.1 (once in ten years), but without global warming it would have a probability of 0.001 (once in a thousand years).

We seem to be having several "once in a thousand years" heatwaves per decade these days.

[mbostleman]

Gotcha.

[retrac]

I don't mean to be dismissive, but simple statistics. A record winter by itself is just a freak incident. As is a record hot summer. But what are the probabilities? One record cold day broken after 80 years? Improbable but not downright implausible. Year after year after year of record highs? Just coincidence?

[mbostleman]

Makes sense. I don’t have a good grasp on what the actual data is over time. My primary awareness is the extreme events that make the news.

[johnchristopher]

You are some steps behind the climate change deniers list of refutations (in more or less general chronical order):

- there are no climate change

- climate change is not because of humane activities

- climate change isn't that bad

- climate change might be good overall

- climate change is business as usual: improvise, adapt, survive

You can find more claims and counter claims https://skepticalscience.com/global-warming-cold-weather.htm here. I picked up that one following your question about cold winter.