NASA Data Peers into Greenland’s Ice Sheet

NASA's Goddard Space Flight Center, Greenbelt, Maryland ^ | January 23, 2015, updated August 7, 2017 | George Hale, ed by Holly Zell

[SunkenCiv]

This new map allows scientists to determine the age of large swaths of Greenland’s ice, extending ice core data for a better picture of the ice sheet’s history. “This new, huge data volume records how the ice sheet evolved and how it’s flowing today,” said Joe MacGregor, a glaciologist at The University of Texas at Austin’s Institute for Geophysics and the study’s lead author.

Greenland’s ice sheet is the second largest mass of ice on Earth, containing enough water to raise ocean levels by about 20 feet. The ice sheet has been losing mass over the past two decades and warming temperatures will mean more losses for Greenland. Scientists are studying ice from different climate periods in the past to better understand how the ice sheet might respond in the future.

One way of studying this distant past is with ice cores. These cylinders of ice drilled from the ice sheet hold evidence of past snow accumulation and temperature and contain impurities like dust and volcanic ash that were carried by snow that accumulated and compacted over hundreds of thousands of years. These layers are visible in ice cores and can be detected with ice-penetrating radar.

Ice-penetrating radar works by sending radar signals into the ice and recording the strength and return time of reflected signals. From those signals, scientists can detect the ice surface, sub-ice bedrock and layers within the ice.

New techniques used in this study allowed scientists to efficiently pick out these layers in radar data. Prior studies had mapped internal layers, but not at the scale made possible by these newer, faster methods. Another major factor in this study was the amount of Greenland IceBridge has measured.

[SunkenCiv]

Peering into the thousands of frozen layers inside Greenland’s ice sheet is like looking back in time. Each layer provides a record of not only snowfall and melting events, but what the Earth’s climate was like at the dawn of civilization, or during the last ice age, or during an ancient period of warmth similar to the one we are experiencing today. Using radar data from NASA’s Operation IceBridge, scientists have built the first-ever comprehensive map of the layers deep inside the ice sheet.

NASA | Greenland's Ice Layers Mapped in 3D | January 23, 2015 | NASA Goddard

[SunkenCiv]

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[Repeal The 17th]

“...containing enough water to raise ocean levels by about 20 feet...”
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I need to see the math before I believe that.

[lurk]

Wait. Hasn’t the ice all melted?

[NetAddicted]

Read later.

[chiller]

So they think it’s floating just like Guam? 20 ft ?

STFU

[MadMax, the Grinning Reaper]

So the Greenland ice-sheet has been losing mass. No sheet!

[MAGAthon]

29 Aug: Climate Depot: Marc Morano: Scientists rip UN IPCC report: MIT’s Dr. Richard Lindzen: ‘Demonizing CO2 is just crazy’…’Ignore the climate crisis’ — Dr. Nir Shaviv of Hebrew U.: ‘They’re totally missing fact that the sun has a big effect on climate’
MIT Climate Scientists Dr. Richard Lindzen: When asked his opinion of Israeli solutions to climate change, Lindzen said: “Solution implies there is a problem.” The real question is if the plan’s worth doing. To that, he replied: “Not at all.” “Demonizing carbon dioxide is just crazy,” said [MIT climate scientist Richard] Lindzen. “It means we have a population that’s forgotten elementary biology. They don’t remember photosynthesis. We’ve already benefited due to the increase in CO2 by probably over a trillion dollars increase in agricultural productivity. The earth is greening due to this.”

Nir Shaviv, a professor of physics at Hebrew University, told JNS that he feels many climate scientists are under pressure to produce alarming reports. There is “such a large climate industry that people need to publish things that show a large effect [from man-made emissions], or they don’t get grants,” he explained. Shaviv said the IPCC’s scientists are not looking at all the evidence. “The thing that they’re totally missing is the fact that the sun has a big effect on climate. We can simulate it in large-scale simulations.” Shaviv: “So I’m totally confident after 20 years that the link is there, the sun has a large effect on climate.”...
https://www.climatedepot.com/2021/08/29/scientists-rip-un-ipcc-report-mits-dr-richard-lindzen-demonizing-co2-is-just-crazy-ignore-the-climate-crisis-dr-nir-shaviv-of-hebrew-u-theyre-totally-missing-fact-that-the-sun/

[crusty old prospector]

As with most “studies,” it just sounds like a boondoggle. Throw in a few words about globull warming.

[Telepathic Intruder]

The ice sheet has enough water to raise ocean levels by 20 feet.

It has been losing mass over the past two decades.

Ocean levels are the same as 20 years ago.

Something doesn’t add up.

[gundog]

It would all have to be in the atmosphere. Which kind of defies the water cycle, unless the atmosphere is a hell of a lot warmer than it was 20 years ago.

[gundog]

Just doing it quickly...and not necessarily without error....it would take an ice sheet of 1,000 meters thickness covering Greenland’s area to raise the area currently covered by the world’s oceans 20 feet. I see a figure of 2-3,000 meters...real precise, I know...for the thickness of Greenland’s ice sheet. I have no idea how much land area would be flooded. but it must be pretty substantial.

[cranked]

Prolly going to use the imagery for their next global ‘we are doomed in 9.5 years’ climate change propaganda release...../s

[PIF]

In the image from the video :

Green is ice laid down in the present geological age - the Holocene
Blue is from the Last Ice Age
Red is from the Eemian (130,000-115,000 BC)

[PIF]

Ocean levels are the same as 20 years ago.

Something doesn’t add up.

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Only if you leave out the Antarctic ...

[maddog55]

That’s pure climate change BS propaganda. That amount of ice is like an ice cube in a bathtub.

Unfortunately.. the believers will say NASA says so.

[radmanptn]

Numbers are from web searches and rounded.
Area of Greenland ice sheet 660235 Sq Mi.
Average thickness of Greenland ice sheet 0.95 Mi
Ice volume 660238 Sq Mi x 0.95 Mi = 627223 Cu Mi
Density convert ice to water 627223 Cu Mi x 0.9 = 564500 Cu Mi
Area of earths oceans 1.4 x10(8) Sq Mi
Sea level rise 564500 / 1.4 x10(8) = 0.004 Mi
Mi to feet 0.004 Mi =21 Ft
That would be a vertical rise, that does not take into account sloped shore lines and water level rise in river deltas, so the ocean rise would be less. Some one else needs to figure that out.

[SunkenCiv]

Heh, y'think? The Greenland keyword has one, or a few, topics about how many gigatons of ice have accumulated in a short time frame. Inland areas that are below sealevel (Qattara Depression and some other spots in Africa, California's Death Valley and Salton Sea, etc) could become the world's flood prevention basins. The Dead Sea is on the list of course, but flooding that would also drown the Galilee, and beside agriculture, there's plenty of economic activity in those parts. Also, the geographic barriers on both ends are something like 600 meters high.

[GingisK]

That ice is sitting on top of a land mass. It isn’t floating.

[maddog55]

I’ll stand by my metaphor..