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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

#241

Post by Insanity »

Ilnsk wrote: post #221
aeroman wrote: post #122

Earlier quoted context omitted.

As a "cloud person", I just want to add a few things to the description of how clouds affect the climate (and why high clouds have a wamring effect). All clouds are white, so they all reflect sunlight back into space (during the day), cooling the Earth. All clouds are (almost) black in the infra-red, meaning the amount of energy they emit in the infra-red is determined by their temperature. Colder clouds emit less en…

I wish I were a cloud person.

When I read that first sentence, I thought “what has cloud (software) to do with this”

Re: Ice core scientists in East Greenland reach bedrock

#242

Post by ricardobeat »

orangepurple wrote: post #157
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…

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.

Nuclear facilities seem pretty fragile / demanding, I doubt one would survive any kind of apocalyptic event. The infrastructure supporting it will be gone.

Re: Ice core scientists in East Greenland reach bedrock

#243

Post by kfrzcode »

aeroman wrote: post #122
ChuckMcM wrote: post #41

This is a very important project. There is a joke in here about "why not wait 2 years for the ice to melt off if you wanted to look at the mud underneath?" But as the article states, "'This will change climate models because it redefines our basic understanding of how ice moves,' explains Dorthe Dahl-Jensen." Much, if not the majority, of climate science is the creation of models (differential equations mostly) that…

As a "cloud person", I just want to add a few things to the description of how clouds affect the climate (and why high clouds have a wamring effect). All clouds are white, so they all reflect sunlight back into space (during the day), cooling the Earth. All clouds are (almost) black in the infra-red, meaning the amount of energy they emit in the infra-red is determined by their temperature. Colder clouds emit less en…

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?

Re: Ice core scientists in East Greenland reach bedrock

#244

Post by analog31 »

anigbrowl wrote: post #200
javajosh wrote: post #189

Earlier quoted context omitted.

Note that the individual license for Matlab is $149/year [0], which isn't crazy IMHO. 0 - https://www.mathworks.com/pricing-licensing.html?prodcode=ML...

Agreed, it's sofa change for an institution. But I remember cost being a big obstacle when I first wanted to learn serious programming around 1990, so I feel like free programming languages are better.

The institutional cost is more AFAIK, but should still be pocket change -- one productive week pays for it. But the price is just high enough to trigger all sorts of weird management wastes. Especially if you envision wanting more than one installation, or are in an austerity-culture organization.

While you're dealing with the time and aggravation of budget approval and recurring license management, I've got my Python and Arduino toolchains installed on literally every computer that I touch: At home, my office, the labs, etc.

Re: Ice core scientists in East Greenland reach bedrock

#245

Post by dredmorbius »

orangepurple wrote: post #157
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…

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.

Re: Ice core scientists in East Greenland reach bedrock

#246

Post by fullstackchris »

ricardobeat wrote: post #242
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.

Nuclear facilities seem pretty fragile / demanding, I doubt one would survive any kind of apocalyptic event. The infrastructure supporting it will be gone.

isnt that the case with any advanced technology? (including wind and solar)

Re: Ice core scientists in East Greenland reach bedrock

#247

Post by almostnormal »

Two numbers from the article: The oldest ice is 120000 years old. The ice is moving at 58 m/years.

If these numbers are correct the oldest ice has travelled almost 7000 km. Greenland isn't that large, and it did not shrink. The age estimate is probably correct.

The speed must have been a lot lower in the past?

Re: Ice core scientists in East Greenland reach bedrock

#248

Post by dredmorbius »

pmayrgundter wrote: post #208
wheelerof4te wrote: post #183

Earlier quoted context omitted.

"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…

The figure I've found is 2800 km^3 of approximately granite, which at 2.7 tonnes per cubic meter gives about a billion gigatons ejecta. I've never found a CO2 estimate, but did find that it's a significant amount of that mass, as is SO2. It wasn't worth me doing more of a sketch since it's not clear how to model the effects of such a massive system. I was struck tho, that the magnitude of this and a few other events…

Wikipedia cites a range of 2,000 -- 13,000 km^3.

https://en.wikipedia.org/wiki/List_of_largest_volcanic_erupt...>

As for the gaseous component of ejecta:

Water vapour is consistently the most abundant volcanic gas, normally comprising more than 60% of total emissions. Carbon dioxide typically accounts for 10 to 40% of emissions.

https://en.wikipedia.org/wiki/Volcanic_gas>

Citing: H. Sigurdsson et al. (2000) Encyclopedia of Volcanoes, San Diego, Academic Press.

(Late edit: though I note that this seems to discuss percentages of gaseous emissions, not total ejecta. Anyone have a better source here?)

One of the largest volcanic events I'm aware of is the Siberian Traps eruption, about 250 mya, with a volume of about 4 million km^3, another three orders of magnitude greater than Tomba.

This has been linked to the Permian–Triassic mass extinction event, with the mechanism being release of methane clathrates and/or stimulating growth of a microbe which released vast quantities of methane into the atmosphere, killing ~81% of all extant marine species and 70% of terrestrial vertebrate species.

https://en.wikipedia.org/wiki/Siberian_Traps>

"The level of atmospheric carbon dioxide rose from around 400 ppm to 2,500 ppm with approximately 3,900 to 12,000 gigatonnes of carbon being added to the ocean-atmosphere system during this period."

-- Wikipedia, citing Wu, Yuyang; Chu, Daoliang; Tong, Jinnan; Song, Haijun; Dal Corso, Jacopo; Wignall, Paul B.; Song, Huyue; Du, Yong; Cui, Ying (9 April 2021). "Six-fold increase of atmospheric pCO2 during the Permian–Triassic mass extinction". Nature Communications. 12 (1): 2137. Bibcode:2021NatCo..12.2137W. doi:10.1038/s41467-021-22298-7.

https://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extin...>

Re: Ice core scientists in East Greenland reach bedrock

#249

Post by almostnormal »

aeroman wrote: post #122
ChuckMcM wrote: post #41

This is a very important project. There is a joke in here about "why not wait 2 years for the ice to melt off if you wanted to look at the mud underneath?" But as the article states, "'This will change climate models because it redefines our basic understanding of how ice moves,' explains Dorthe Dahl-Jensen." Much, if not the majority, of climate science is the creation of models (differential equations mostly) that…

As a "cloud person", I just want to add a few things to the description of how clouds affect the climate (and why high clouds have a wamring effect). All clouds are white, so they all reflect sunlight back into space (during the day), cooling the Earth. All clouds are (almost) black in the infra-red, meaning the amount of energy they emit in the infra-red is determined by their temperature. Colder clouds emit less en…

Not all water vapor is clouds. Where relative humidity is too low it comes with all the warming but none of the cooling effect. A tiny change in humidity (cloud/no cloud) can change things significantly.

Re: Ice core scientists in East Greenland reach bedrock

#250

Post by Nevermark »

Insanity wrote: post #241
Ilnsk wrote: post #221

Earlier quoted context omitted.

I wish I were a cloud person.

When I read that first sentence, I thought “what has cloud (software) to do with this”

Not series, maybe a bit serious:

Cloud computing energy use appears to be on an exponential trend driven by general trends (all things automated), with new forms of automation compounding competitive pressures (deep learning models quickly getting larger, more powerful, more useful, and more versatile in a way erasing many lines holding back past competition.)

At some point, it seems inevitable that computing usage will be a first level climate driver, regardless of how green the energy is.

Harnessing orbital solar, fission and fusion power, may solve the CO2 energy problem, without requiring us to steal the biosphere's energy needs, but will eventually create a massive waste heat energy problem.

Unless we find someway to efficiently transfer mass amounts of heat energy off of Earth.

Or we eventually limit computing on Earth, and export that to the Moon and beyond.

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