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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

#181

Post by slashdev »

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?

It’s mostly caused by Milankovitch cycles. Which are cyclic variations in our orbit around the sun.

The earth varies in distance to the sun and axial tilt and precession. Like waves, there factors can either overlap and somewhat cancel or they can stack for a larger effect.

Re: Ice core scientists in East Greenland reach bedrock

#182

Post by jppope »

altacc wrote: post #106
johnnyApplePRNG wrote: post #71

That's a rate of about 4.3 centimeters per hour. Can anybody elaborate as to why this process takes so long?

It's not a continuous 24/7/365 process. They have a drilling season each year, I believe about 6-8 weeks, have drilled at 2 different sites and been interrupted by the pandemic.

why was ice drilling interrupted by the pandemic?

Re: Ice core scientists in East Greenland reach bedrock

#183

Post by wheelerof4te »

adolph wrote: post #72
sgirard wrote: post #7

Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature above Greenland was 5°C warmer than today."

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 past millennia.

Re: Ice core scientists in East Greenland reach bedrock

#185

Post by applied_heat »

jppope wrote: post #182
altacc wrote: post #106

Earlier quoted context omitted.

It's not a continuous 24/7/365 process. They have a drilling season each year, I believe about 6-8 weeks, have drilled at 2 different sites and been interrupted by the pandemic.

why was ice drilling interrupted by the pandemic?

Getting supplies such as food and shift changeovers?

Re: Ice core scientists in East Greenland reach bedrock

#186

Post by bequanna »

BenjiWiebe wrote: post #163
samstave wrote: post #117

There is a design for an ice-melting-slurry-bot that could be made, where the outer diameter of the bore is melted by heat/lasers - where the lasers/heat is also projected into a cone at the point of the bore-ing machine, where the center pipe is a vacuum to slurp up the slurry as it melts the ice around the bore-head...

You aren't going to be able to vacuum slurry up from several km down.

Even with a very small diameter hose/pipe?

Re: Ice core scientists in East Greenland reach bedrock

#187

Post by lukev »

renegade-otter wrote: post #169
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…

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…

This is pretty ahistorical. Most of the world's great civilizations have been from warmer climates. Northern Europe is an exception, not the norm.

Re: Ice core scientists in East Greenland reach bedrock

#188

Post by BurningFrog »

mytailorisrich wrote: post #98
sgirard wrote: post #7

Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature above Greenland was 5°C warmer than today."

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…

> Bottom line: we need large scale carbon capture quickly

The short term solution/bandaid is pumping SO2 into the stratosphere while we figure out carbon capture.

Re: Ice core scientists in East Greenland reach bedrock

#189

Post by javajosh »

anigbrowl wrote: post #110
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…

A lot of modeling is moving toward Julia, so if you don't want to give money to Mathworks here are some alternatives: https://juliaclimate.github.io/Notebooks/

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...

Re: Ice core scientists in East Greenland reach bedrock

#190

Post by sgirard »

newfonewhodis wrote: post #49
sgirard wrote: post #7

Interesting: "Towards the base, the ice is more than 120,000 years old and dates back to the last interglacial period, a time when the atmospheric temperature above Greenland was 5°C warmer than today."

I'm not a scientist so I'm curious why this is interesting.

I find it interesting because it raises questions that I don't have answers to. For example:

- What caused the temperature above Greenland to be 5°C warmer than today? Why is it cooler now compared to 120,000 years ago? What causes the interglacial periods? Is glaciation the more common state of the climate?

- The article says the ice sheet is melting at the bottom? Why? Pressure from above? Friction from movement? Heat from the Earth? Something else?

- Was the ice sheet shrinking or growing when the temperatures above Greenland were 5°C warmer than now? Does existence of the ice sheet imply that 5°C warmer for some period of time is not enough to melt the Greenland ice sheet?

- How much climate data has been lost to melting from the bottom? Is the ice sheet thickening or thinning compared 120,000 years ago? How would we know?

- How much has the Greenland land mass moved in 120,000 years due to plate tectonics? Could this have impacted the ice sheet in this short amount of time?

- Humans adapt. How did humans adapt to a climate that was warmer by up to 5°C 120,000 years ago?

- How long did the warm temperatures persist 120,000 years ago? 10,000 years? 50,000 years? Or more?

- Could a cooling climate be more worrisome to humanity than a warming one?

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