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Comment by DennisP | Hacker News Reader

There's about a thirty-year delay, just like turning up a burner on the stove takes a while to heat the water. By the time people feel it that much, it'll be far too late.

We have to put on the brakes before we get irreversible feedback effects, where natural systems start emitting enough greenhouse gases that it doesn't matter anymore what we do.

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Not sure what data you are basing this on. I tend to think we are heading into a cooling period.

We possibly would have, if we weren't warming the climate through human activity.

> I would say it is significant that temperatures of the most recent decade exceed the warmest temperatures of our reconstruction by 0.5 degrees Fahrenheit, having few -- if any -- precedents over the last 11,000 years. Additionally, we learned that the climate fluctuates naturally over the last 11,000 years and would have led to cooling today in the absence of human activity.

https://www.theguardian.com/environment/climate-consensus-97...

Current temperature is maybe the hottest in recorded history (which is about 150 years) and that is a big maybe. Its definitely not the hottest in human history. Medieval warming period was much warmer than it is now. I would even argue the 1930s were hotter as well.

> Current temperature is maybe the hottest in recorded history (which is about 150 years)

“Recorded history” is a period much longer than 150 years.

> Medieval warming period was much warmer than it is now.

No, it wasn't. Global aversge temperature is above the peak of anything that might be in the MWP today (the MWP had a really small global effect, with different local warming periods in different regions.)

> I would even argue the 1930s were hotter as well.

Well, you can argue anything, but finding data to support that argument might be difficult.

Until about the mid-90s of last century the Medieval Warm Period was for climate researchers an undisputed fact. The IPCC itself reported this as such in their 1990 report and included this graph.

https://i1.wp.com/www.science-skeptical.de/wp-content/upload...

Here is another chart published by IPCC in 1995 it shows both the Medieval warm period and the 1930s as being hotter than it is now.

https://stevengoddard.files.wordpress.com/2011/05/screenhunt...

Since then there has been an effort to erase this data from the record because it contradicts current climate change narrative. None of what Im saying is a theory. These are facts and there are loads of leaked emails and testimony under oath that says as much.

https://www.youtube.com/watch?v=u1rj00BoItw

Up your research game my friend.

> Until about the mid-90s of last century the Medieval Warm Period was for climate researchers an undisputed fact.

The MWP is, if not undisputed, a widely accepted fact, though of dubious significance; a very slight rise in average global temperatures over a several centuries long period does show up, as, within that long period, do shorter and much more pronounced and non-synchronized regional warm periods.

Global average temperatures in the MWP, though, were notably lower than today.

> The IPCC itself reported this as such in their 1990 report and included this graph.

Maybe, maybe not. Given your misrepresentation on the next one, I'm not taking your word for it, and in any case there is no clear indication of what that is a graph of; it looks a lot like the graph of European temperatures provided in your other link, but with lower resolution and presumably an earlier end date, which of course is immaterial to the discussion of global temperature trends.

> Here is another chart published by IPCC in 1995 it shows both the Medieval warm period and the 1930s as being hotter than it is now.

Nope, that's a chart published by someone else later that claims to be based on a diagram published by the IPCC which (obviously) doesn't show temperatures today at all (1995 is more than two decades ago, and global warming didn't stop then), and, in any case, doesn't show global temperature at all, either, only European temperature. Regional temperature trends don't always reflect global trends. Yes, Europe experienced notable local warming in the MWP and the early 20th century (and dramatic local cooling in the period sometimes called the “Little Ice Age” which, IIRC, doesn't show up at all in global trends and is at least in part within the global MWP, though the warm regions that brought up the global aversge at the time were elsewhere.)

> Since then there has been an effort to erase this data from the record

No, the local trends that the charts you point to reflect are widely acknowledged by climate scientists today—they are, however, local, not global.

> Up your research game my friend

Hey, I'm not the one who offered a chart without reading the caption. Having a good research game is more than just spamming links without understanding the content.

They're both basic climate physics, and not related to short-term fluctuations.

Further, your example was an analogy.

When you add energy input to a system, it doesn't immediately reach its new equilibrium temperature. That's not an analogy, it's another example of the same physical process.

> it's another example of the same physical process

That's an analogy.

Then all of experimental physics is based on analogies.

When a comparison between phenomena is made for the purpose of explanation, yes, analogy is commonly used in the teaching of physics.

But it is better to say that experimental physics is based on the collection of data about a particular phenomenon, and fitting those data to mathematical models to test how well their predictions hold. And that is not analogy.

In an experiment you try out a simple system to see how it works. Then you use those same physical principles to figure out how a more complex system works. An example would be heating water on a stove to see how fluids respond to energy input.

> And that is not analogy.

technically analogy has a broad definition that applies anytime you compare two things.

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