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Ice core scientists in East Greenland reach bedrock

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Re: Ice core scientists in East Greenland reach bedrock

#261

Post by sixo »

ummonk wrote: post #258
kfrzcode wrote: post #243

Earlier quoted context omitted.

I will give you the benefit of doubt given it's Hacker News you likely are an expert, but this feels like one of those "sounds too intuitive to be that simple" type complex factors. Any literature on the topic from which I can improve my understand?

What part of it do you doubt? It’s obvious that clouds are white, and it’s obvious that they are cooler than the earth and even colder higher up (clouds form because the adiabatic expansion of rising air cools it down and causes water to condense, and the higher up you go the colder the atmosphere due to greater expansion - anybody who has hiked the mountains has experienced this). The only assertion here that one ha…

Granting that the two effects counteract each other, it is surprising that the crossover point would happen within the range of variation of actual clouds on Earth. My uninformed guess would have been that nearly all clouds' effects are dominated by only one of the two effects—probably, by the cooling effect.

Re: Ice core scientists in East Greenland reach bedrock

#262

Post by aledalgrande »

ummonk wrote: post #258
kfrzcode wrote: post #243

Earlier quoted context omitted.

I will give you the benefit of doubt given it's Hacker News you likely are an expert, but this feels like one of those "sounds too intuitive to be that simple" type complex factors. Any literature on the topic from which I can improve my understand?

What part of it do you doubt? It’s obvious that clouds are white, and it’s obvious that they are cooler than the earth and even colder higher up (clouds form because the adiabatic expansion of rising air cools it down and causes water to condense, and the higher up you go the colder the atmosphere due to greater expansion - anybody who has hiked the mountains has experienced this). The only assertion here that one ha…

I think the concept of the albedo of the poles is another simple idea that explains why melting poles would be bad and accelerate global warming further, because by being white they reflect back sunlight for a huge area. Kinda intuitive if you have ever touched the black (opposite color) coolers on a desktop computer and felt your hand fry

Re: Ice core scientists in East Greenland reach bedrock

#263

Post by zosima »

lehi wrote: post #175
mytailorisrich wrote: post #98

Earlier quoted context omitted.

Iirc, the CO2 concentration now as been pumped up higher than it was then, which is in part what is worrying because temps might then potentially shoot even higher. Bottom line: we need large scale carbon capture quickly because even if we reach net zero CO2 will take millenia to drop back to the level it was pre-industrial revolution. Edit: I wouldn't focus on "pre-industrial levels" specifically, the point is that…

The Keeling Curve is eye-opening for understanding our current versus (pre-)historical CO2 levels: https://tywkiwdbi.blogspot.com/2023/07/introducing-keeling-c...

One of the many misleading things done by climate scientists is to splice together data derived via different measurement methods.

The CO2 curve 800000 years back is an excellent example.

CO2 in air bubbles in ice will diffuse into the ice during the many millenia the ice have been stored under pressure. You can therefore expect the ice core CO2 to be lower than hypothetical atmospheric measurements at the same time.

The diffusion is expected to progress fastest at the start, and then more slowly.

Still the artifact is absolutely obvious as the CO2 concentration peaks are lower and lower the further back in time it goes.

Yet of course someone had to splice it all together and not even add error bars.

Re: Ice core scientists in East Greenland reach bedrock

#264

Post by zosima »

dredmorbius wrote: post #245
orangepurple wrote: post #157

Earlier quoted context omitted.

This raises a very critical point. Nuclear is the only dependable energy source. Fossil fuels will run out or go out of favor. Solar and wind on the other hand will become victims of the next major volcanic eruption as ash destroys them or renders them ineffective.

An eruption significant enough to impact solar and wind generation globally will also affect other critical requirements of humanity, and the Earth's ecosystem, globally. Which is to say: You Will Be Having Bigger Problems. Recovery from regional meterological catastrophes is well within human capabilities.

Bigger problems than no power in the worst year imaginable. Give me a break.

Re: Ice core scientists in East Greenland reach bedrock

#265

Post by slashdev »

slashdev wrote: post #176
thomasahle wrote: post #142

Earlier quoted context omitted.

See also this timeline of the last four inter-glacial periods: https://co2coalition.org/wp-content/uploads/2021/09/104-4000... It also shows how crazy it would be if we get the projected 2-3 degrees average temperature increase. Even in a period where we'd expect to be going into a new ice age; instead shooting to a previously unseen high temperature.

On the other hand if we only have 2-3 degrees of warming, if that’s enough to prevent the next ice age, didn’t we just dodge a massive icy bullet? Might we not one day thank ourselves for doing something reckless and stupid that actually worked out? Yeah a warmer climate brings all kinds of horrible changes. But food still grows in the northern hemisphere. A colder climate is arguably even worse for us. By the way, t…

[flagged]

Re: Ice core scientists in East Greenland reach bedrock

#266

Post by TSiege »

kuprel wrote: post #180
slashdev wrote: post #176

Earlier quoted context omitted.

On the other hand if we only have 2-3 degrees of warming, if that’s enough to prevent the next ice age, didn’t we just dodge a massive icy bullet? Might we not one day thank ourselves for doing something reckless and stupid that actually worked out? Yeah a warmer climate brings all kinds of horrible changes. But food still grows in the northern hemisphere. A colder climate is arguably even worse for us. By the way, t…

I didn't realize that the vast majority of the time Earth is in an ice age. What causes it periodically like this?

The planet is 4.5 billion years old! 400,000 years is just roughly 0.0089% of earth's history (and I rounded up!)

Re: Ice core scientists in East Greenland reach bedrock

#267

Post by mr_toad »

deafpolygon wrote: post #184

Isn't this the basically the plot to the prequel of The Thing?

Digging too deeply has been a plot point in many stories.

There’s even an urban legend that a failed Soviet borehole project broke into ‘hell’

https://en.wikipedia.org/wiki/Well_to_Hell

Re: Ice core scientists in East Greenland reach bedrock

#268

Post by devoutsalsa »

foota wrote: post #197
sleet_spotter wrote: post #127

Earlier quoted context omitted.

As the hole gets deeper, the amount of time to bring up core sections and send the drill back down become significant. That combined with the previously mentioned short field season. Drilling more than a few hundred meters becomes very difficult logistically as well, especially in such a remote setting.

Who knew, drilling is O(N^2)

We need a couple more bore holes to do a Tower of Hanoi style question for interviews.

Re: Ice core scientists in East Greenland reach bedrock

#269

Post by sci_prog »

wheelerof4te wrote: post #183
adolph wrote: post #72

Earlier quoted context omitted.

120k years ago in context: * 170,000 years ago: humans are wearing clothing by this date. * 125,000 years ago: the peak of the Eemian interglacial period. * ~120,000 years ago: possibly the earliest evidence of use of symbols etched onto bone * 75,000 years ago: Toba Volcano supereruption that may have contributed to human populations being lowered to about 15,000 people https://en.wikipedia.org/wiki/Timeline_of_preh…

"75,000 years ago: Toba Volcano supereruption that may have contributed to human populations being lowered to about 15,000 people." The key question is: How much CO2 did that super-eruption emit into the atmosphere? In our hurry to attribute climate change to our meager impact on this planet, we tend to forget what horrors an eruption of this magnitude can cause. And who knows how many of them happened during the pas…

Not even close to what we as humans emit. The rate of the global annual natural CO2 emissions are 1-2 orders of magnitude slower than anthropogenic emissions.

Re: Ice core scientists in East Greenland reach bedrock

#270

Post by sanderjd »

zosima wrote: post #264
dredmorbius wrote: post #245

Earlier quoted context omitted.

An eruption significant enough to impact solar and wind generation globally will also affect other critical requirements of humanity, and the Earth's ecosystem, globally. Which is to say: You Will Be Having Bigger Problems. Recovery from regional meterological catastrophes is well within human capabilities.

Bigger problems than no power in the worst year imaginable. Give me a break.

Yes, no agriculture is an even bigger problem than no power.
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