GOCE reveals gravity dip from ice loss (w/ Video)

September 26, 2014
Changes in Earth’s gravity field resulting from loss of ice from West Antarctica between November 2009 and June 2012 (mE = 10–12 s–2).  A combination of data from ESA’s GOCE mission and NASA’s Grace satellites shows the ‘vertical gravity gradient change’.. Credit: ESA

Although not designed to map changes in Earth's gravity over time, ESA's extraordinary satellite has shown that the ice lost from West Antarctica over the last few years has left its signature.

More than doubling its planned life in orbit, GOCE spent four years measuring Earth's in unprecedented detail.

Scientists are now armed with the most accurate gravity model ever produced. This is leading to a much better understanding of many facets of our planet – from the boundary between Earth's crust and upper mantle to the density of the upper atmosphere.

The strength of gravity at Earth's surface varies subtly from place to place owing to factors such as the planet's rotation and the position of mountains and ocean trenches.

Changes in the mass of large sheets can also cause small local variations in gravity.

Recently, the high-resolution measurements from GOCE over Antarctica between November 2009 and June 2012 have been analysed by scientists from the German Geodetic Research Institute, Delft University of Technology in the Netherlands, the Jet Propulsion Lab in USA and the Technical University of Munich in Germany.

Remarkably, they found that the decrease in the mass of ice during this period was mirrored in GOCE's measurements, even though the mission was not designed to detect changes over time.

The animation, based on measurements from ESA’s GOCE satellite and the NASA–German Grace mission, shows that ice lost from West Antarctica has caused a dip in Earth’s gravity. Credit: ESA

Using to assess changes in is not new. The NASA–German Grace satellite, which was designed to measure change, has been providing this information for over 10 years.

However, measurements from Grace are much coarser than those of GOCE, so they cannot be used to look at features such as Antarctica's smaller 'catchment basins'.

For scientific purposes, the Antarctic ice sheet is often divided into catchment basins so that comparative measurements can be taken to work out how the ice in each basin is changing and discharging ice to the oceans. Some basins are much bigger than others.

By combining GOCE's high-resolution measurements with information from Grace, scientists can now look at changes in ice mass in small glacial systems – offering even greater insight into the dynamics of Antarctica's different basins.

They have found that that the loss of ice from West Antarctica between 2009 and 2012 caused a dip in the gravity field over the region.

In addition, GOCE data could be used to help validate satellite altimetry measurements for an even clearer understanding of ice-sheet and sea-level change.

Using 200 million measurements collected by ESA’s CryoSat mission between January 2011 and January 2014, researchers from the Alfred Wegener Institute in Germany have discovered that the Antarctic ice sheet is shrinking in volume by 125 cubic kilometres a year. The study, which was published in a paper published on 20 August 2014 in the European Geosciences Union’s Cryosphere journal, also showed that Greenland is losing about 375 cubic kilometres a year. Credit: ESA

ESA's CryoSat satellite, which carries a radar altimeter, has recently shown that since 2009 the rate at which ice is been lost from the West Antarctic Ice Sheet every year has increased by a factor of three.

And, between 2011 and 2014, Antarctica as a whole has been shrinking in volume by 125 cubic kilometres a year.

Johannes Bouman from the German Geodetic Research Institute said, "We are now working in an interdisciplinary team to extend the analysis of GOCE's data to all of Antarctica.

"This will help us gain further comparison with results from CryoSat for an even more reliable picture of actual changes in ice mass."

This new research into GOCE's gravity data revealing ice loss over time is being carried out through ESA's Earth Observation Support to Science Element.

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tejolson
1 / 5 (6) Sep 26, 2014
Can we send Europa into Mars by reflecting light into it?
TegiriNenashi
1 / 5 (13) Sep 26, 2014
Ice loss increased by factor of 3? What is the reason one may wonder? Is it that Antarctic temperatures shot up lately [which has been predicted long long time ago: Mercer 1978, Nature]? What is more believable, that increased temperatures caused sea ice to expand all around Antarctica to the record high, or this particular team had miscalibrated their gravity sensor, so that it is attracted to mountain of global warming BS?
Vietvet
5 / 5 (12) Sep 26, 2014
Sea ice has not expanded "all around" Antarctica. Total extent as increased by 1% a decade since 1979. Some areas have gained and others have lost while land based ice has shrunk.

http://earthobser...outh.php
runrig
5 / 5 (11) Sep 26, 2014
Ice loss increased by factor of 3? What is the reason one may wonder? Is it that Antarctic temperatures shot up lately [which has been predicted long long time ago: Mercer 1978, Nature]? What is more believable, that increased temperatures caused sea ice to expand all around Antarctica to the record high, or this particular team had miscalibrated their gravity sensor, so that it is attracted to mountain of global warming BS?

What is entirely believable is your and you likes desperate need to deny my friend.

Anyone with a scientific brain would tie this finding with your implication that the Antarctic environment must be cooling due the increase in sea-ice. Try thinking along the lines of salinity, eh?
That's not the only reason BTW.
Returners
1 / 5 (4) Sep 26, 2014
Can we send Europa into Mars by reflecting light into it?


Europa has too much water. It would flood mars several kilometers deep across the entire surface if you crashed them together....well, after the planet cooled back down a bit.

Europa has several times as much water as all the oceans, ice, and ground water on Earth combined.
Uncle Ira
3.4 / 5 (5) Sep 26, 2014
Can we send Europa into Mars by reflecting light into it?


Europa has too much water. It would flood mars several kilometers deep across the entire surface if you crashed them together....well, after the planet cooled back down a bit.

Europa has several times as much water as all the oceans, ice, and ground water on Earth combined.


Skippy you are good with the math problems. Did you calculate out the amount that gets splashed back out into space during the crash landing? Ol Ira is not the scientist-Skippy like you ain't either but I would think maybe some lot of it will get wasted.
Returners
4.2 / 5 (10) Sep 26, 2014
Ice loss increased by factor of 3? What is the reason one may wonder? Is it that Antarctic temperatures shot up lately [which has been predicted long long time ago: Mercer 1978, Nature]? What is more believable, that increased temperatures caused sea ice to expand all around Antarctica to the record high, or this particular team had miscalibrated their gravity sensor, so that it is attracted to mountain of global warming BS?


It's carrying a Radar Altimeter, which means they know exactly how high it is, which means they know if it's orbit is altered due to fluctuations in gravity.

The data is also cross-referenced with the GRACE experiment, so it's two different forms of direct measurement. They can't both be that wrong.
Returners
2.3 / 5 (6) Sep 26, 2014
Skippy you are good with the math problems. Did you calculate out the amount that gets splashed back out into space during the crash landing? Ol Ira is not the scientist-Skippy like you ain't either but I would think maybe some lot of it will get wasted.


Obviously some would, but the amount depends on the type of collision. If it's a glancing blow, I'd say more of it escapes, if it's head-on or t-bone it could penetrate deeper into the rock, and the average momenta would be harder to overcome to throw much of it back into space.

Still, you'd be talking about the biggest collision in the Solar System since human beings have been on the Earth, maybe even since the Late Heavy Bombardment.

It'd be easier and more efficient, and a h ell of a lot safer, to just harvest the water you need using ordinary space transports, instead of trying to de-orbit Europa to hit Mars.

I was just answering his question.

Yeah, it could be done with enough fusion rockets. Water->hydrogen->He.
Returners
2 / 5 (4) Sep 26, 2014
You could easily imagine multi-kilometer sized chunks of Mars rock, and water/vapor/ice being thrown back into space.

I never said it would be pretty, I was just answering the question,a nd giving a reason it wouldn't be a good idea: it's just too much water.

Not to mention it would cause another "heavy bombardment" and possibly wipe out life on Earth due to the ejecta mentioned already.
gkam
4.6 / 5 (9) Sep 26, 2014
The Deniers will find some irrelevant aspect to question, so they can throw the whole thing out.

But here it is: Massive ice losses in Antarctica, new trade routes through the former iced-in Arctic Northern Passages, major losses of ice from Greenland - the facts to deny.

They cannot understand science is not like business or finance or religion or politics or the other fields we invented:Saying so and screaming it has no effect on reality.

They may have to stomp their foot.
Egleton
1 / 5 (3) Sep 26, 2014
I'm disappointed.
Where are the giant egos and teeny weeners?
As for the greening mars thing when will the penny drop that once you are out of the gravity well you stay out?
Gravity sucks.
" If you thought it was a long way to the corner shop, Space is a lot bigger" D. Adams.
Here is how to do it children. No-not you Mr. teeny weener. You don't have an invite.
https://www.youtu...QCm54dfY
Returners
1.7 / 5 (6) Sep 27, 2014
Egleton:

I realize "gravity sucks" bu tthere may be things which can't be easily accomplished in space.

I have suggested Dyson Swarms and orbital platforms. Colonies on Europa and Ceres trading Water for Nitrogen, carbon, and construction materials. 1/100th Earth gravity, and no atmosphere means lauch costs are near-zero.

Colonies on Titan trading Carbon and Nitrogen for water and other materials. Atmospheric density is huge, mass is low, thus you can have "floating cities" almost like Star Wars, at ultra-low maintenance costs.

Power supply comes from fusion, with fission power supply primer plants.

I worked out conceptual ways of safely doing Lunar colonization as well. Obiously you need most structures to be radiation shielded with brick made from Lunar regolith.

Eventually, a monstrous network of solar panels could be used to transmit power via lasers to other colonies.

You could also mine 3He for export for fusion power, eventually.
Returners
1.6 / 5 (7) Sep 27, 2014
Right, in that design, you're inside orbiting tubular or spherical mega-structure with probably solar power on the outside. It has spun gravity, and is large enough to develop it's own internal micro-climate.

My designs worked similarly, with tubular living quarters spinning perpendicular to the solar panel plane. I calculated you could make solar fields several kilometers wide in a 2-d plane per platform, by using existing materials. No idea how big using nano-tube based materials, because there isn't enough research yet, but it should be bigger and/or lighter.

Anyway, you'd water-cool the panels (makes them 10% more efficient) and pump the waste heat to steam generators, or for hot water for cooking, cleaning, and bathing, thus the total energy efficiency is expected to be near 90% or so.

The lowest grade waste heat is pumped through radiators on the outside(dark side), to allow the heat to radiate away via infrared (NASA does this).

I also developed steps to control climate.
Uncle Ira
3.9 / 5 (11) Sep 27, 2014
I also developed steps to control climate.


Hooyeei, Skippy. Is there anything you can't do better than the professionals? (Getting high on the drugs don't count no.)
antigoracle
1 / 5 (12) Sep 27, 2014
Oh, the desperation of the AGW Cult, their global warming CO2 is only melting the ice under which there is significant geothermal activity.
Vietvet
4.9 / 5 (11) Sep 27, 2014
Oh, the desperation of the AGW Cult, their global warming CO2 is only melting the ice under which there is significant geothermal activity.


Repeating a lie doesn't make it true.

You have no evidence but that is what trolls do.
runrig
5 / 5 (10) Sep 28, 2014
Oh, the desperation of the AGW Cult, their global warming CO2 is only melting the ice under which there is significant geothermal activity.


A small contribution under the Thwaits glacier only.
Give a denier a sniff of a possible get-out and they're on it like a whippet on a rabbit.
Your disgust at climate science dissolves when it comes up with something you can latch on to and distort to fit your confirmation bias, eh Anti?
Atta boy...... true to form and far, far, beyond where the fairies live.

FF f***ing sake.
antigoracle
1 / 5 (9) Sep 28, 2014
Yes Mr No More Ice Age, it's tiny like your brain. Yet this is the only area your AGW Cult can find melting of any significance. That global warming, man made CO2, is sure picky and that is what the AGW Cult calls "science". Give an AGW Chicken Little a glass of stupid and they gulp it down like there is no tomorrow.
Vietvet
4.6 / 5 (9) Sep 28, 2014
As usual antiwearingpanties doesn't know the facts.

http://www.skepti...ers.html
Egleton
1 / 5 (6) Sep 28, 2014
@ Returners. I like it. Forget the turkeys.
@ "Uncle" Ira. Bath time. Your mommies calling.
Uncle Ira
3.4 / 5 (5) Sep 28, 2014
@ "Uncle" Ira. Bath time. Your mommies calling.


Well good morning to you too Skippy. Now that you got my attention, why don't you sit down and let the Returnering-Skippy finish teaching you everything about everything.
Vietvet
5 / 5 (7) Sep 28, 2014
"Geothermal heating is not enough by itself to have caused the observed changes"

That's from the University of Texas at Austin study the right wing press censored from their reporting.

https://news.vice...ice-caps
runrig
5 / 5 (6) Sep 29, 2014
Yes Mr No More Ice Age, it's tiny like your brain. Yet this is the only area your AGW Cult can find melting of any significance. That global warming, man made CO2, is sure picky and that is what the AGW Cult calls "science". Give an AGW Chicken Little a glass of stupid and they gulp it down like there is no tomorrow.

And therein lies your problem - your concept of the physics involved is one dimensional. A complex system can never behave as you think. This total ignorance feeding your ideological based confirmation bias. I don't full understand rocket science but I don't doubt we have gone to the moon.
FF f##^^ng sake.
antigoracle
1 / 5 (4) Sep 30, 2014
I don't full understand rocket science but I don't doubt we have gone to the moon.

Is that how you convince yourself that the hundreds of failed AGW Cult climate models can predict doom and gloom.
runrig
5 / 5 (3) Oct 05, 2014
I don't full understand rocket science but I don't doubt we have gone to the moon.

Is that how you convince yourself that the hundreds of failed AGW Cult climate models can predict doom and gloom.

It's not a matter of being convinced....the only thing certain in life is death and taxes. It's called following the science and using common sense and probability.

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