Hacker News Reader

Hacker News

Comment by toss1 | Hacker News Reader

Full thread

toss1

Great visualization from Randall Munroe:

https://xkcd.com/1732/

Literally everyone should see this.

Edit: Evidently many people still do not get the point

The point is that yes, climate has changed in the past, and the individual values are not the problem.

The PROBLEM is that it has never changed this FAST. By orders of magnitude.

Velocity changes everything.

Consider just taking a sip of your coffee 1000X as fast as usual.

Instead of bringing your cup the 2' from table to lip in 1 sec, it's 1/1000 sec. You will require multiple explosions to accelerate it to 2000fps/609m/sec/Mach2, and back to zero.

Same description of events, entirely different process and results.

Similar for species and ecosystems to adapt at 1000X the speed they've ever seen.

View on HN

He picked his starting point well.

And before they start panicking, they should see this: https://commons.wikimedia.org/wiki/File:All_palaeotemps.svg

The XKCD comic starts at the coldest moment in history known to mankind.

What do you take away from this?

That its not nearly as much as an catastrophe as some HN readers wish it to be.

Think about it. The carbon didn't spawn in the earth, it got deposited there. Coal and oil are sediment based. It used to be in circulation previously. And yet Earth is still habitable.

Oh geeze, that graph is really concerning. We're approaching temperatures where humans weren't living!

People live in Australia right now. And Morocco!

Giving you the benefit of the doubt you're not trolling, it seems you're laboring under the belief that, say, "2C of warming" means it'll always be 2C hotter where people live.

It does not. It means the mean will be at +2C. At this level of warming, we'd see crazy +15C / -15C swings regularly in many areas, often in a matter of days. It means plants that have started growing in earnest suddenly are in the midst of serious frost, killing them (something we're already seeing in my country in the EU, regularly). It means potentially many climate tripwires being triggered, too.

+2C is hell for tens, possibly hundreds of millions of people. And we're likely not stopping there.

I'm serious. People live and survive in places with conditions that i would consider uninhabitable. If dissent is trolling to you, reconsider your ideas.

I challenge you to back up the +15C / -15C numbers.

> And yet Earth is still habitable.

For humans? We did not exist for most of that chart. There's only one peak that coincides with the 200000 or so years of human existence, and your chart shows us on track to beat it. We don't have records from 100000 years ago either, we know humans as a whole survived and that's about it. I think it's a bit presumptuous to extend that to all 8 billion people alive today.

I guess my point is that it's possible that humans will survive this AND it will be catastrophic for our society.

The choice to start at 2000 BC is interesting, because as soon as you zoom out more, the story completely changes:

https://www.researchgate.net/publication/356606430/figure/fi...

https://www.climate.gov/sites/default/files/styles/full_widt...

Randall chose one of the lowest point every in the history of earth as the "baseline". We are still in one of the coldest period ever for earth. The recent rise of temperature is significant, but not unprecedented. Before we reach a point that one could qualify as a "hot earth", we would need to warm up by an additional 10 to 15 C°

The problem is not the absolute temperature change, but the rate of change.

And the impact of the change to our costly and slow to build infrastructure.

The xkcd chart starts at 20,000 BC, not 2,000. Well before permanent settlements, agriculture, trade, etc. that our current civilization relies upon.

> Randall chose one of the lowest point every in the history of earth as the "baseline".

Randall's graph starts at a little over 4C lower than current temperatures. The most recent minimum on your first graph is 7C below current temperatures.

Your 2nd graph couldn't be shown in Randall's format because it would either take too long to scroll, or it wouldn't have the resolution needed to show the dramatically higher rate of change.

> The recent rise of temperature is significant, but not unprecedented.

The rate of change is unprecedented.

> Before we reach a point that one could qualify as a "hot earth", we would need to warm up by an additional 10 to 15 C°

Billions will die before that.

>> Before we reach a point that one could qualify as a "hot earth", we would need to warm up by an additional 10 to 15 C°

> Billions will die before that.

Yeah that's the true point of people who are concerned (like yours truly): the planet will do just fine. Humanity simply won't be around to see it.

Reply on news.ycombinator.com