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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

#291

Post by midoridensha »

pavlov wrote: post #193
renegade-otter wrote: post #169

Earlier quoted context omitted.

Maybe humans become more developed because it got colder? Even on a country and global scale, the south is usually "behind" the north. It's hot, no one wants to do anything. The American south (Arizona, Florida) were tiny and unimportant until air conditioning entered the chat. Phoenix was at 100 thousand people in the fifties. The cold makes us think, the cold make us survive, keeps us on the edge - where we need to…

On the other hand there’s something to be said for a comfortable climate that leaves people with time to think when the everyday isn’t a constant complex struggle. The Inuits of Greenland and Sami people of Lapland didn’t have Aristotle or Confucius.

Maybe there's a "sweet spot". Too warm and not enough seasonality leads cultures to not be that productive, but too cold and daily life is just too much of a struggle to invent calculus. Greenland and Lapland are probably too far north to have decent agriculture, and never had large enough populations to develop much civilization. Cultures that had people like Aristotle or Confucius had very large populations for the time.

Re: Ice core scientists in East Greenland reach bedrock

#292

Post by Cthulhu_ »

lumost wrote: post #148
detourdog wrote: post #130

Earlier quoted context omitted.

It's interesting because the whole ice cap as we know it is around 120k years ago which I don't consider the long ago on human development scale. This also appears to mean that in the past 120K there wasn't a polar ice cap. I read that as the worst case scenario we should be using for long term planning. This also may help determine how fast the ice was built and how fast it will melt. I'm completely an armchair pond…

This will also assuredly fuel some interesting ideas about the origin of the Piri Reis map. A 120k year old ice sheet could mean that humans once lived on Antarctica. It does make one wonder if any ancient sea fearing humans happened to carve a world map into a durable material such as granite which could have survived until the modern historic era. Maybe such a map, or other mythological artifact fueld the Roman ide…

Even without an ice sheet, would antarctica be hospitable? It'd still be cold and a desert I imagine, in darkness through the winter, etc.

Re: Ice core scientists in East Greenland reach bedrock

#293

Post by Cthulhu_ »

pavlov wrote: post #193
renegade-otter wrote: post #169

Earlier quoted context omitted.

Maybe humans become more developed because it got colder? Even on a country and global scale, the south is usually "behind" the north. It's hot, no one wants to do anything. The American south (Arizona, Florida) were tiny and unimportant until air conditioning entered the chat. Phoenix was at 100 thousand people in the fifties. The cold makes us think, the cold make us survive, keeps us on the edge - where we need to…

On the other hand there’s something to be said for a comfortable climate that leaves people with time to think when the everyday isn’t a constant complex struggle. The Inuits of Greenland and Sami people of Lapland didn’t have Aristotle or Confucius.

That we know of; did they have a system of writing?

I find it hard to believe they wouldn't philosophise at all. Confucius got famous (like sun tzu et al) because his ideas were written down, published and spread.

Re: Ice core scientists in East Greenland reach bedrock

#294

Post by midoridensha »

uncletammy wrote: post #125
toshk wrote: post #109

I love humans. They somehow decided to start drilling, and not give up & get funding for 7 years. We are a crazy but exciting bunch of organisms.

> We are a crazy but exciting bunch of organisms. I read this as "crazy but extinct bunch of organisms"

>I read this as "crazy but extinct bunch of organisms"

That'll be true too, eventually. The way we're going now, it might not even be that long...

I think we should build a monument on the Moon with an archive of data of our cultures (including a copy of Wikipedia), built to survive for as long as possible, so that alien explorers can learn about us after we destroy ourselves, and learn how we managed to do so so they don't repeat the same mistake.

Re: Ice core scientists in East Greenland reach bedrock

#295

Post by orangepurple »

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.

Nuclear facilities can probably continue to operate amid persistent cloud cover and ash. Wind turbines and solar can not. Agriculture would have to shift artificially lit greenhouses.

Re: Ice core scientists in East Greenland reach bedrock

#296

Post by Deskegende »

almostnormal wrote: post #247

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?

Or it was moving in a different direction

Re: Ice core scientists in East Greenland reach bedrock

#297

Post by zosima »

japanuspus wrote: post #282
zosima wrote: post #263

Earlier quoted context omitted.

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.…

Not sure if you are trolling of really believe this to be true, but for anyone else assuming good faith: The diffusion aspect is (of course) well-modeled, see e.g. references under "past greenhouse gasses" at [0]. [0]: https://www.antarcticglaciers.org/glaciers-and-climate/ice-c...

Also, btw, this one is fun:

"Carbon dioxide measurements from older ice in Greenland is less reliable, as meltwater layers have elevated carbon dioxide (CO2 is highly soluble in water)."

Re: Ice core scientists in East Greenland reach bedrock

#298

Post by chakintosh »

sdfghswe wrote: post #2

Can't believe they don't show a photo of what appears to be a 10 meter in diameter, 2.7km deep hole.

Just for fun:

Volume of ice = π * (radius)^2 * height

where radius = diameter / 2 and height is given in meters.

Volume = π * (10m / 2)^2 * 2700m

Volume ≈ 354,177.66 cubic meters

The density of ice is approximately 917 kilograms per cubic meter.

Weight of ice extracted = Volume * Density of ice

So, the weight of the ice extracted from the hole is approximately 324,856,152.42 kilograms.

Greta must be fuming.

In all seriousness though, ice cores are a few inches in diameter, not 10 meters. Unless they take one of those tunnel boring machines and send it vertically down through earth.

Re: Ice core scientists in East Greenland reach bedrock

#299

Post by wasmitnetzen »

TSiege wrote: post #266
kuprel wrote: post #180

Earlier quoted context omitted.

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!)

Humans are only about 300 000 years old though, so that part is much more relevant to our species than the rest.

Re: Ice core scientists in East Greenland reach bedrock

#300

Post by credit_guy »

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 have a question for a cloud person, maybe you can answer it.

When it rains, where does the latent heat go? The latent heat of evaporation (or condensation) is absolutely huge. Condensation means heat is released. I did a back of the envelope calculation. 2 mm daily rainfall x 500 million km2 = 10^15 kg; each kg of water holds 2.26 MJ of latent heat, and there are 86400 seconds in a day, so that's 26.15 W, so overall 26150 TW. The Earth receives about 173000 TW from the Sun, so this is about 15% of the energy received from the Sun. Obviously, not all the 15% goes out to space, but about how much does go to space?

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