Can we puny humans produce enough energy to melt the huge icecap? Some math helps.
Guest essay by Julius Sanks
When discussing climate with people who do not have technical backgrounds, I have learned much of the climate discussion is a foreign language to them.
Phrases like “Dalton minimum” or “Atlantic multidecadal oscillation” make their eyes glaze over. Once, after I explained what causes wind, the reply was, “my head hurts.” So, I no longer try to explain atmospheric science. Besides, I am an engineer, not a meteorologist. I have had better luck by sharing simple examples that let people reach conclusions on their own about human versus natural influence. Telling them I can show them the math if they want to see it adds credibility, because few, if any, alarmist publications intended for the general public include any math to support their claims. Describing the energies that drive weather, and therefore climate, is a good way to do this.
So, I take them through a few examples of how much energy is involved and how miniscule human activity is by comparison. Done properly, this lets a non-STEM person grasp the huge amounts of energy involved.
One of my favorites is Anthony’s essay that debunks the Hiroshima equivalent alarmism:
https://wattsupwiththat.com/2013/06/23/getting-cooked-by-hiroshima-atomic-bomb-global-warming/
Another excellent example is the amount of energy in an average hurricane. According to NOAA-OAR-AOML, an average hurricane releases 200 times the world’s electrical energy production just to produce the clouds and rain.
http://www.aoml.noaa.gov/hrd/tcfaq/D7.html
There are about 70-100 tropical cyclones per year worldwide. Seventy storms would average 14,000 times the world electricity production every year.
These types of examples are good for communicating with nontechnical people. They let people relate atmospheric physics to their own life experience and everyday understanding of the world in which they live — even if that understanding might be skewed or incomplete.
And then there’s the ice. We are supposedly melting the ice; the literature is filled with papers making this claim. These papers invariably whine about human activity warming the planet, but they never seem to get around to discussing how much energy is actually required, or how it gets to the ice. But do humans really generate enough energy to melt significant amounts of ice?
A case in point is from a recent Grist article:
Ice Apocalypse
Rapid collapse of Antarctic glaciers could flood coastal cities by the end of this century.
By Eric Holthaus
November 21, 2017
In a remote region of Antarctica known as Pine Island Bay, 2,500 miles from the tip of South America, two glaciers hold human civilization hostage.
Stretching across a frozen plain more than 150 miles long, these glaciers, named Pine Island and Thwaites, have marched steadily for millennia toward the Amundsen Sea, part of the vast Southern Ocean. Further [sic] inland, the glaciers widen into a two-mile-thick reserve of ice covering an area the size of Texas.
There’s no doubt this ice will melt as the world warms. The vital question is when.
The glaciers of Pine Island Bay are two of the largest and fastest-melting in Antarctica. (A Rolling Stone feature earlier this year dubbed Thwaites “The Doomsday Glacier.”) Together, they act as a plug holding back enough ice to pour 11 feet of sea-level rise into the world’s oceans — an amount that would submerge every coastal city on the planet. For that reason, finding out how fast these glaciers will collapse is one of the most important scientific questions in the world today.
…Antarctica is a giant landmass—about half the size of Africa—and the ice that covers it averages more than a mile thick. Before human burning of fossil fuels triggered global warming, the continent’s ice was in relative balance: The snows in the interior of the continent roughly matched the icebergs that broke away from glaciers at its edges.
Now, as carbon dioxide traps more heat in the atmosphere and warms the planet, the scales have tipped.
A wholesale collapse of Pine Island and Thwaites would set off a catastrophe. Giant icebergs would stream away from Antarctica like a parade of frozen soldiers. All over the world, high tides would creep higher, slowly burying every shoreline on the planet, flooding coastal cities and creating hundreds of millions of climate refugees.
All this could play out in a mere 20 to 50 years—much too quickly for humanity to adapt.
…There’s a recurring theme throughout these scientists’ findings in Antarctica: What we do now will determine how quickly Pine Island and Thwaites collapse. A fast transition away from fossil fuels in the next few decades could be enough to put off rapid sea-level rise for centuries. That’s a decision worth countless trillions of dollars and millions of lives.
Source: https://grist.org/article/antarctica-doomsday-glaciers-could-flood-coastal-cities/
Holthaus is in fact reporting on a piece that appeared in Nature. The original is here: https://www.nature.com/news/antarctic-model-raises-prospect-of-unstoppable-ice-collapse-1.19638
Now, 11 feet [3.353 meters] of sea level rise is a lot of water, which means a lot of melted ice. How much ice? And how much energy is needed to melt it? We can use some high school physics in a Fermi analysis to establish a benchmark of sorts that nontechnical people can understand. To do this, we need to agree on some basic numbers and then use them to examine the situation in Antarctica.
This assumes the ice is at standard temperature and pressure (STP — essentially air pressure at mean sea level and temperature at 32°F/0°C). More on that later.
First, let’s examine some basic volume and mass definitions. Some values are rounded.
1 liter of water has a mass of 1 kg, by definition.
Freeze it and the volume increases. 1 kg ice is 1.09 liters, or 0.92 kg/liter.
One cubic km = 1012 liters.
So 1 km3 of ice = 9.2×1011 kg. This is our basic unit of mass for melting the ice.
A generally accepted value for the total ocean area is 3.618 x 108 km2. Raising this surface by 1 mm requires 361.8 Km3 of additional water.
Raising the ocean by 3.353 meters requires 361.8 Km3 X 3353 mm = 1.21X106 Km3 of liquid water, which comes from 1.32X106 Km3 of glacial ice.
How much energy is needed to melt 1.32X106 Km3 of ice?
The question is important because, regardless of ice thickness, whether it is on land or is a shelf, wave action, collapse due to instability, or temperature gradients, there is a specific amount of heat energy that must transfer into any mass of ice before it can melt. This is basic physics, and it holds regardless of how the heat transfers (e.g., advection, conduction, etc.). The only debate, then, is how much of that heat comes from human activity versus natural forces, and how did human activity cause its portion of the heat to arrive at the ice? And if Holthaus’s article is correct, the ice will melt in 20 to 50 years. This gives us a rate of heat transfer, and that can give us insight into how credible it is to blame human activity.
So, now it’s on to the energy:
It takes 333.55X103 J to melt 1 kg of ice.
Doing the math, we see it takes 3.07X1017 J to melt a cubic km of ice. This is our basic unit of heat energy for melting any large amount of ice in Antarctica, or anywhere else.
Now, back to the two glaciers. We have determined how much ice is involved in that 11-foot ocean rise: 1.32X106 Km3. To melt it, the ice must receive 1.32X106 Km3 X 3.07X1017 J, or 4.05X1023 J. This is true regardless of what process gets the heat to Antarctica. A steady melt would require 2.03X1022 J per year to melt it in 20 years, or 8.1X1021 J per year to melt it in 50 years.
We can argue until the cows come home about how that much heat can reach the glaciers. But for our nontechnical friends, it’s interesting to compare the energy requirement with how much energy humans produce. In other words, if humans set out to deliberately melt the Thwaites and Pine Island Glaciers, could they even do it?
It should be noted the Antarctic ice sheet is only 2.74 percent of the planet’s surface. If human output excites the atmosphere evenly, a reasonable consideration is only that percentage of energy is directly acting on the ice. But let’s attack the problem more directly.
According to the US Energy Information Administration, in 2016 the world produced 84.412479 quadrillion (84.412479X1015) BTU. That converts to 8.906X1019 J, consisting of fossil fuel (the largest component), nuclear, and renewable. And if we used all of the world’s energy to do nothing but melt the ice, we could not do it in 20 years, or even in 50 years. We could do it in about 4,500 years. Here is the math:
4.05X1023 J ÷ 8.906X1019 J = 4,547.5 years.
https://www.eia.gov/totalenergy/data/browser/#/?f=A&start=1949&end=2016&charted=4-6-7-14
That’s just to melt two glaciers. What would it take to melt all of Antarctica?
Per the National Snow and Ice Data Center (NSIDC), Antarctica contains about 30 million km3 of ice.
https://nsidc.org/cryosphere/quickfacts/icesheets.html
So, for Antarctica, we need 3.07X1017 J X 30X106 km3 = 9.21X1024 J to melt everything.
How many years would it take?
9.21X1024 J ÷ 8.906×1019 J/year = 103,413.43 years.
When talking to your non-STEM friends, just round it off to 100,000 years. This number, and Anthony’s Hiroshima analysis, makes me think human influence on the weather, and therefore climate, is so miniscule it cannot be measured with existing technology.
But these durations are clearly minimum numbers, and not very good at that. Why? Because they rely on some invalid assumptions:
- It assumes all the ice is at STP. This cannot be true. Average surface temperature is approximately -49°C, so the energy “well” is much deeper than at STP. Specific heat of ice is 2108 J/kgK or 103.3 kJ to raise the temp of each kilo of ice to 0°C. That does not include the heat of fusion, 333.55 kJ/kg. Therefore, it takes additional energy just to warm the ice to a melting point. Not much is known about temperatures deep in the ice, but NSIDC’s THERMAP data indicate temperatures are below 0°C, at least down to 500 meters. Deep in the ice, there is enormous pressure, but the temperature is unknown. H2O’s phase diagram shows eleven different types of ice and numerous triple points. If exotic types of high-pressure ice are present, it’s likely their mass per unit volume differs from type I ice at STP. That would mean the energy requirements differ for exotic forms of ice. https://nsidc.org/data/thermap/
- Obviously, it is not possible to apply 100% of our energy to melt the ice. We would be limited to a much smaller amount, with correspondingly longer times to melt.
- The ice will try to re-freeze. This causes a feedback loop, extending the melting program. We can only prevent this by keeping water and air temperatures in contact with the ice above freezing. That diverts energy from doing the melting.
I know, I know. This is a very simplistic analysis that ignores the complexities of actual heat transfer. But that’s the point; non-STEM people can follow it if they know a little math.
And yes, the alarmists would argue human emissions are indirectly causing heat to transfer to Antarctica, and this type of analysis is therefore irrelevant. So what? They must show how human emissions transfer that heat, and how much heat is being transferred.
My goal here is to show the enormous energy levels involved and how ridiculous it is to blame humans for any significant ice melt. That’s my hypothesis; let the alarmists come up with the null.
Now let’s build some power stations and melt Antarctica!
H/T to Grady Gillis for sharing some ideas, and especially for saving me from a very basic unit conversion error.
Julius Sanks is an engineer and manager with experience developing weather forecasting systems and environmental satellites.
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Arm 1 million humans with an industrial sized acetylene torch kit and let them lose.
/sarc
If we get to that point, just move the ice systematically to someplace you want fresh water, via ship, letting it melt in transit. I can just see the job posting now: Wanted, Ice Miners. Will train.
Sorry, Julius, but this is a totally silly analysis. The fact that the energy in a hurricane dwarfs our power generation capacity should have been a clue. The energy in the earths atmosphere dwarfs our own actual energy use because the energy input from the sun dwarfs everything, and drives everything. The sun has plenty of energy to melt all the ice on the planet. It’s back to school for you Julius.
How about just disproving my math? You actually argue the sun, not humans, is the cause. I think you have missed my point, which was to challenge the notion that humans are to blame for any ice melt.
Your math may be correct, but it’s irrelevant. No one has ever argued that it’s the heat from combustion that is warming the atmosphere. It’s the heat from the sun that will melt the ice, if it’s to be melted, and that’s a notion that I’m highly skeptical of.
“You actually argue the sun, not humans, is the cause.”
As Tom says, no-one expects waste heat from combustion to melt the ice. What may do it is radiative forcing from anthropogenic GHGs (ours). Heat from that dwarfs combustion, so yes, your calculation is pointless.
Nick has not explained how there would ever be close to enough heat to melt the surface of Antarctica before the rest of the planet was frying in 60C heat.
The claim that the energy of human activity, industrial or otherwise, is responsible for melting glaciers, ice sheets, etc. has never been made. The actual claim is vastly different:
addition of greenhouse gases from human activity results in increased greenhouse effect which retains SOLAR ENERGY in the earth system longer, resulting, in part, in higher temperatures that melt more ice than would otherwise melt.
This has nothing to do with the energy use/release, or heat production, of human activity, only with the CO2 and other gas releases into the atmosphere from human activity.
The particular melting reported by Eric Holthaus has been linked to geothermal vents by some amount of evidence and by warm water from outside the Antarctic by hypothesis.
AndyHce April 17, 2018 at 5:23 pm
What warmer water?
Antarctica is not melting. Any glacier retreat in West Antarctica is due to subglacial volcanoes.
The continent has gained mass all during the rise in CO2. While Arctic sea ice declined from 1979 to 2012 in the dedicated satellite record, Antarctic sea ice grew from 1979 to record high in 2014. Freak WX events and the recent super El Nino caused less Antarctic ice since then, but CO2 had nothing to do with it.
I found it rather entertaining and my sense of the environmental zeitgeist is that many people overestimate the power of mankind compared to nature in an abstract sense. These simple calculations show the energies involved in the natural world dwarf our output which you seem to understand already so understanding why you object to the essay is a mystery. Perhaps Julius can write a follow up essay for STEM folks in reading comprehension.
All the skeptic peer-review papers ….. will.they be part of the next IPCC report?
Obviously not all of them as the IPCC summarises papers.
However, if you are actually interested in the environment it may make sense to actually read the IPCC reports. It may surprise you to know that the sceptical peer-reviewed papers are included.
For example, the alarm over AGW comes from models of the climate that say we are warming the world dangerously. However, the IPCC reports that the models over-estimate the warming. The very epitome of climate change scepticism!
See the last report, look at Box 9.2 form IPCC AR5 (the last report; Climate Models and the Hiatus in Global Mean Surface Warming of the Past 15 Years
If you care about the environment look at the science, not press releases from partisan groups.
All the skeptic peer-review papers ….. will.they be part of the next IPCC report?
Stop making sense…
Antarctica froze over completely about 33.6 million years ago when CO2 was 1,200 ppm. I mean that is a long, long time ago and CO2 was many times higher than it will ever get to in today’s world.
Why did it freeze over and turn into one big glacier when CO2 was so high? Well, it is at the south pole where it gets very little sunlight compared to other places on the planet. Simple enough.
http://www.newscats.org/wp-content/uploads/2018/04/30221502_952507618249375_732273060227055758_n.jpg
It did melt back by about half from 27 million years ago to 14 million years ago, but that is because the Antarctic Circumpolar Current was disrupted by the small left-over continental cratons between South America and Antarctica. These cratons are now well out into the Atlantic thanks to continental drift and are now the South Georgia and South Sandwich Islands.
Now the Sun is capable of melting out Antarctica. The total solar energy received by the Earth from the Sun each year is about 3.865 X 10^24 joules so that is a good 100 times more that the calculations above assume. But if we took all the energy the Earth receives from the Sun in a year and put it all into Antarctica, well the rest of us would freeze to death within 2 days.
So, millions of fricken’ years, the early part of it when CO2 was in the 1,200 ppm range.
Any way you stokes it, history/reality says 1200ppm CO2 in the atmosphere won’t melt Antarctica ice.
1200ppm CO2 would be a good thing. Optimum for plants. Greenhouses are that level. No human has died in a greenhouse except by natural causes. We need more CO2 NOT less. I love watching the Bloomberg CO2 9 decimal places clock go up every milli second. Unfortunately it only increases 2ppm per year. such a puny amount. The plants are crying for more.
What about the fact that Antarctica is dark for much of its winter and will cool as it radiates away energy without being replenished by the Sun.
Another calculation that shows the insanity is to consider that if all of the ice on the planet melted, the increase in energy by reduced reflection when averaged across the surface would not even be enough W/m^2 to achieve half of what the IPCC claims is caused by doubling Co2 alone. When you do the calculation, you must take into consideration that 2/3 of the planet is covered by clouds and reflects about the same as ice anyway.
Ya since the total albedo is 30% how much of that is reflection by Antarctica? Has anybody figured it out?
of course, it was done.
And is answer is: pretty much zero, for a very simple reason : the polar areas are small, relative to the whole Earth,
You can calculate yourself, with undergraduate notion of trigonometry, or just basic formula for circular segment area for the relevant angle (~23.5° ).
Answer : ~1% of the sun rays reach the polar zone
OK. Now that the issue of melting in the Antarctic has been solved, lets us move on to the next problem.
And that is; “How many angels can dance on the head of a pin. And will the direction of rotation affect the rotation of the earth.
Hmmmn. Direction of rotation of the pin? Same as, or different from, the conventional (north pole) view of the earth looking towards the solar system ecliptical plane?
Or direction(s) of rotation(s) of the angel(s) on the head of the pin?
What is the latitude of the pin?
Is it (or one or more of the angels) rotating perpendicular to the earth’s surface, or at an angle to the earth’s surface?
And, as always, what are the masses of the angels and pin? Bic, fountain, or feathered?
Are we to assume the pin (or one or more of the angels) are to be rotating about their center of mass, or slightly off of their center of angelic mass?
now, that is outrageous domination of angels over pin, and discrimination against devils, and LGBTetcphobia,as you failed do mention them.
Hadn’t it already all been melted?
The ice doesn’t have to melt for the sea level to rise; it just needs to break up and fall into the sea. The map shows how much ice in Antarctica is being exposed to an awful lot of freshly-arriving warm water.
I doubt there’s any aspect of the science and maths the global community of publishing climate scientists is not aware of.
But hey, reassurances from know-alls are always popular.
Stephanie Hawking
Er, uhm, no. Dead wrong.
Only the very ends of the few coastal glaciers are “over water” around the Antarctic continent. You are arguing the impossibility of an land area covered with ice the size larger than Canada or Russia, covered with solid ice the height of the Appalachians will be melted if some of the ice on the edges (Hudson River/New York harbor, San Francisco Bay, or Puget Sound) melted.
Yes, the Pine Island Glacier is large. Yes, parts of it do extend out over the water. But is is little, compared to the continental ice.
By the way, in August in both 2016 and 2017, for the first time ever in recorded history, the Arctic sea ice in the Bering Sea and Sea of Okhotsk did not melt all the way out.
More ominously, in 2017, the sea ice in the Gulf of St Lawrence remained solid for weeks longer in July and August than ever before. (It did refreeze back the same date as average. but we need to see how much thick, multi-year ice remains through this year down at latitudes 48, 58, and 60. )
The average Hudson Bay daily sea ice extents for 2016-2017-2018 are higher now than in recent years.
Does the absurdity of what you wrote become apparent?
I prefer the judgement of experts. You don’t know what you are talking about and thus you are quite at home here.
Please specify which facts you have decided you disagree with because they do not meet your prejudices and desires.
“I prefer the judgement of experts.”
Stephanie prefers an appeal to authority over facts.
======
“It appears to me that those who rely simply on the weight of authority to prove any assertion, without searching out the arguments to support it, act absurdly. I wish to question freely and to answer freely without any sort of adulation. That well becomes any who are sincere in the search for truth.”
– Vincenzo Galileo
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“The map shows how much ice in Antarctica is being exposed to an awful lot of freshly-arriving warm water.” – Stephanie
► Antarctic winter sea ice extent sets new record in 2014 – NOAA
I prefer the judgement of experts
=======
Experts are worse than the average population at predicting the future.
The average population at least has the common sense to recognize that no matter how much you know, there is still an infinity of things you don’t know.
I prefer the judgement of experts
=======
Experts are worse than the average population at predicting the future.
The average population at least has the common sense to recognize that no matter how much you know, there is still an infinity of things you don’t know.
An expert is someone that thru careful study has come to know more and more about less and less. Until after a lifetime of study they know almost everything about almost nothing.
Stephanie Hawking
April 16, 2018 at 8:39 pm
Your appeal to authority followed by ad hominem attack is the refuge of one lacking convincing arguments.
But stick around, Stephanie! You might actually learn something of real value…
“Science is the belief in the ignorance of experts.”
–Richard Feynman
Please cite those whom you imagine to be experts.
@Stephanie Hawking
Typical social science claptrap believe me I know an expert or believe consensus views. That in itself tells you what is wrong with soft science fields and why so many of them are getting into trouble.
Good, since you like the experts, you might want to read what the experts say about your warm water theory and how it is able to breach the Southern Antarctic Circumpolar Current front!
Location of the southern Antarctic Circumpolar Current front (white contour), with -1 degree Celsius sea surface temperature lines (black contours) on Sept. 22 each year from 2002-2009, plotted against a chart of the depth of the Southern Ocean around Antarctica. The white cross is Bouvet Island.
Credits: NASA/JPL-Caltech
Study Helps Explain Sea Ice Differences at Earth’s Poles
SH, how do you know they are experts? How do you know that we aren’t?
Sounds like you, like most alarmists, declare to be experts, anyone who says what you want to hear.
@ur momisugly Hawkings …do you mean these warm ocean waters? …https://earth.nullschool.net/#current/ocean/primary/waves/overlay=sea_surface_temp/orthographic=114.45,-86.72,672/loc=128.206,-63.820
Click in closer to the continent and the water temps are even colder. How quickly do you think that 28 or 30 degree Fahrenheit water can melt ice?
And that isnt even Antarctica’s winter yet
It wont “break up and fall into the sea”. You want to read up on glaciology. What could theoretically happen is that a glacier which is resting on rock below sea-level can, if more than 90 % of the ice height at the glacier front is below sea-level, and the depth to bedrock increases faster inland than the thickness of the glacier does and there are no thresholds or pinning points calve out rapidly (meaning within a few thousand years or so).
This is strictly theoretical. There is no convincing data that it has ever happened in West Antarctica (and in East Antarctica it isn’t even theoretically possible). If it it had ever happened it would have left enormous IRD (Ice-rafted debirs) deposits int the Southern Ocean. Nothing like that has ever been found, not even in Pliocene layers when the West Antarctic was probably periodically ice-free.
I repeat: The ice doesn’t have to melt for the sea level to rise; it just needs to break up and fall into the sea. The map shows how much ice in Antarctica is being exposed to an awful lot of freshly-arriving warm water.
Here some simple explanations:
http://www.newsweek.com/antarctica-melting-below-and-getting-worse-773963
https://www.independent.co.uk/news/science/antarctica-nasa-mantle-plume-arctic-melting-warm-bedrock-study-latest-a8046661.html
https://www.independent.co.uk/environment/antarctica-climate-change-underwater-ice-sheets-melting-glacier-sea-level-rise-a8285336.html
http://www.dw.com/en/antarctica-is-melting-from-below-and-thats-bad-news/a-43239093
No answer has contradicted this with evidence. Just amateur opinion.
The old “Appeal to lack of Authority” argument.
I must say that it is fascinating how Steph considers news magazines to be authoritative.
Regardless, the vast, vast majority of ice in Antarctica is miles away from the sea. And wouldn’t drop off and fall into the sea, no matter how much floating ice was melted.
Stephanie,
1) The newsweek.com article is about floating ice shelves. If they melt, their is no increase in sea level. None. No cause for alarm, regardless of the cause during this naturally warming interglacial period.
2) The independent.co article references a subsurface magma plume that may be melting a local area of the glacier from below. It has absolutely nothing to do with ‘man made global warming’.
3) The 2nd independent.co article asserts underwater warm water currents are melting the west antarctic glaciers. From Earth and Planetary Science Letters, Volume 407, 1 December 2014, Pages 109-122
https://www.sciencedirect.com/science/article/pii/S0012821X14005780
the subsurface beneath the glacier is being warmed by a geothermal dome. No man made warming needed.
4) The dw.com article is more of the same…. warming from below is melting the glaciers. They predictably attribute it to man made global warming but Antarctica is a geothermally active area overlaid by glaciers. Honest evaluations must take this into account but the AGW funding industry cannot afford to do so.
GEOPHYSICS 10 July 2015
High geothermal heat flux measured below the West Antarctic Ice Sheet
http://advances.sciencemag.org/content/advances/1/6/e1500093.full.pdf
You have indicated you ‘listen to experts’ so I have provided a couple of peer reviewed papers to illustrate my points and refute the alarmist newspaper articles you referred to. These peer reviewed expert articles clearly contradict your alarmist magazine stories, as well as your ‘amateur opinion’.
I encourage you to please stick around, you may yet learn something!
SH, can you show that the amount of freshly arriving warm water is greater than in past years?
Or are you one of those know-alls who doesn’t need to actually look up anything.
Hmmmn. Those “under water level” regions of the Antarctic continent are “underwater” BECAUSE the weight of the thousands of meters of icecap sitting ABOVE water level for tens of millions of years (when CO2 has been much higher than now) have compressed the solid rock under the icecap down.
Now, water pressure increases as one goes deeper, but rock is “usually” stronger than water at resisting steady compressive loads. Thus, no part of the icecap is “floating” at all on water, but the ice is solid all the way to bedrock below. The seawater – at 2 to 4 degrees at the surface, -2 to -4 degrees very deep, cannot penetrate between the bedrock and bottom of the icecap because the forces “down” (between ice and rock) are greater than the forces “sideways” between water sideways into the supposed crack.
Under a mountain glacier, the melting water does flow down to the tunnels and rivulets under the icecap – but that’s because the ice is shallower (a few tens of meters) and so has less force “down”. Further, a mountain glacier is characterized by movement and continues downward erosion and grinding. Where movement occurs, the ice is NOT solid nor continuous, but is always ruined with lateral and lengthwise (flow-direction) flaws that allow movement of water, ground-up rock, and ice blocks.
Where the glacier is very thick, it is also not characterized rivers of water underneath.
The very rare occasions when glaciers “run” are intermittent, in steep regions where the water can run down, get trapped momentarily (days or weeks) behind , then float limited sections of the glacier for limited quick travel. Most reports allow 2-3% of the observed time.
The figure Stephanie Hawking shows is worthy of some discussion. However, I think this figure is actually more helpful:
http://cdn.antarcticglaciers.org/wp-content/uploads/2012/06/cross_section_combined.ai_.jpg
Take a look at the bottom part of the figure, which shows a profile of Antarctica which includes ice below and above sea level.
Stephanie was not clear (to me) with her point in bringing up this figure, but I’ll assume it is why Alarmists often mention the West Antarctic Ice Sheet (WAIS). (I’m not referring to Stephanie here – just using her figure to address what Alarmists usually do with it.) Notice that WAIS is grounded but the ground the ice is on is below sea level by 500-1000 meters. The ice shelves (floating) around WAIS do provide some protection for the grounded WAIS – but the ice is exposed to the oceans. Many know this, and some do not. The Alarmist narrative is that if the ice shelves collapse (which they seem to all do periodically), then WAIS could be unprotected, and it too could “collapse” (or break up). We then hear about how much the sea level will rise, etc., etc.
How many articles are there on the topic of ice sheets that include the comment: “… and if all the ice melts….” (followed by the list of tragic consequences). This is a ridiculous fear and I’ll explain why – at least ridiculous for it to happen in even a thousand years. The WAIS concern is similarly flawed, but at least there is something there to work with and the Alarmists have a point about the ice being grounded below sea level. So why is this actually not a real concern then?
Ice shelves and ice sheets are very different. Ice shelves are by their nature structurally weak compared to grounded ice. Remember for an iceberg to float, due to the density difference between ice and water, a chunk of ice will always be 90% underwater and 10% above water. Said another way, the water must be much deeper than the chunk of ice is tall to float it. (For whatever dimension ends up being the height based upon its shape.) From my figure, you can see that WAIS is 500-1000m below sea level but also another 1500-2000m above sea level.
Those who have concerns about WAIS point out that channels are being generated by water under the ice. This happens in some areas but the size of these channels is miniscule compared to the size of WAIS. The further in the channel gets inland then the less water circulation there will be and what is more likely to happen is that the water will freeze. A 5-10 foot deep channel of water will be covered with 8000-9000 feet of ice perhaps at -50C. The Antarctic bottom water is typically -0.8 to +2C. (I don’t know why people refer to water a few degrees above freezing as “warm”). While sea water freezes at ~-2C (depending upon salinity), remember that once the water freezes the ice has very little residual salinity. Ice in the 2nd and subsequent years continues to reduce salinity through cracking and other processes. The melting point returns to around 0C. So the water near the ice or that finds its way under the ice will have a very difficult time thermodynamically to do any melting. It will be already below 0C or even at 2C is thermodynamically week. The energy flow from the water to the ice will cool the water – and if the ice gets close to 0C then it will take a long time to melt as thermal energy moves slowly with small temperature gradients.
Recent exploration of the Ross Ice Shelf earlier this year shows that ice is forming under the shelf – not melting.
https://news.nationalgeographic.com/2018/02/ross-ice-shelf-bore-antarctica-freezing/
So the ice is cold enough to freeze the water beneath it. And this is a shelf – not a sheet! There is 500-1000m of water under the sheet.
If melting under the ice produced any local structural weaknesses then at most, you would have a column of ice 9000 feet tall slump a few feet into the water channel – driving the water out an/or freezing it. There is just now way WAIS can break up like an ice shelf. You would need water depth that is approximately 110% the height of the ice sheet such that the ice could float away. These ideas are put forward by people who have never thought about or studied structures. I don’t see the physics involved in a “break up” of the sheet. (This should be good news – but Alarmists fight it!)
Furthermore, Alarmists talk about ice melting as if it could happen in isolation from the rest of the “global climate”. When ice melts, it cools the air or the water that melts it! When ice is made, the air or water around it gets warmer! Where does the heat come from or go to respectively otherwise? A lot of melting ice will make the atmosphere much colder!
I want to thank Julius for putting together the blog post. I was actually working on something similar. I’ll just sprinkle in a few points from what I was working on.
Alarmists talk about a warming world. We are told that the “global average temperature” is now ~16.5C. Some fear that the “global average temperature” will go up by 4C by the end of this century. Using the approach that Julius used, let’s take a look at a few things. First, how much ice could we melt if we could trade all of the heat energy in the atmosphere with the ice sheets. Let’s start with 16.5C. I’ll give you my assumptions and values used in the calculations. Feel free to change the values – you will see that the story doesn’t really change.
We need to determine the energy in the atmosphere above 0C (since that is the melting point of ice). To do this we need the mass of the atmosphere, the specific heat and the average temperature. I refer you to the figure below which shows a vertical atmospheric temperature profile.
The x-axis gives you the temperature and the y-axis on the left gives you the altitude in km. The red line shows the temperature as you go from the ground up to the top of the thermosphere. What should be immediately noticed (and interesting) is that it is only the air below around 8,000 feet (2.5km) that is above 0C. The top of the thermosphere is excepted as it has almost no mass and no direct thermal coupling. The mass of the atmosphere is 5.15×10^18 kg. 75% of the mass of the atmosphere is contained in the troposphere. I’ll assume 35% is in the first 2.5km, where temperature is greater than 0C. So, the mass we will use is 1.8×10^18 kg. I’m going to use 8C as the average temperature below 2.5km – it appears to actually be lower, but 8C is conservative. The specific heat of the atmosphere is 1,005 J/kg/C. So, we therefore have:
1.45×10^22 Joules in the atmosphere available to melt ice.
Of course, atmospheric energy exists in gradients/bands – and we could never actually get all of this energy circulating over the ice sheets to exchange all of the energy. But because it is an absurd impossibility it also serves as good limit to understand the absolute maximum of what could happen. The reality of course will be much less.
As for the ice: Here are the numbers I used: Antarctica 3×10^7 km3 at -57C average. Greenland 3×10^6 km3 at -30C average. Specific Heat of ice: 2,108 J/kg/C. Heat of fusion of ice: 3.34×10^5 J/kg/C. So therefore, we have:
1.36×10^25 Joules in the ice below 0C. It will take this much energy to melt all of the ice to water at 0C.
So, if we mix all of the energy in the atmosphere with the ice we can melt enough ice to raise sea level by 2.8 inches. I skipped some steps to save time – but I used 220 feet of total sea level rise if all of the ice melts (the commonly accepted figure) and used the ratio of the energies between the ice and the atmosphere. The energy in the ice below 0C is over 900 times that of the atmosphere above 0C. My assumption (for finding the absurd limit) is to assume that we can concentrate the energy of the atmosphere such that it all goes to melting a quantity of ice. It is also possible that the energy would just warm the ice and melt none of it.
So, we could get ~3 inches of sea level rise if we traded all of the thermal energy in the atmosphere above 0C. Here is something else to consider. To do this would bring the atmosphere of Earth below 2.5km to 0C! This is about 6C colder than the coldest point during a glacial period!
If the atmosphere heats by 4C in this century, you could trade that energy for 1.4 inches of sea level rise to cool the atmosphere back down.
A lot more could be said, but I’ll wait to see if there is interest to discuss.
Did I make any mistakes in the calculations or logic?
Ps – another interesting point to consider: For any quantity of ice in Antarctica at -57C, if you melt it to water at 0C and call the energy “E” Joules. Then if you add another “E” Joules to that water it will boil! Melting ice at -57C takes a lot of energy! 75% of which is just to transition state.
William
William,
As we know, it is the ocean that absorbs most of the solar energy and is most responsible for our weather. Before the atmosphere could warm up by 4 degrees, wouldn’t the oceans first need to do so? Similarly, in order for the atmosphere to cool by 4 degrees, the surface water of the ocean will need to cool again, meaning that all of that heat in the ocean needs to be counted toward the heat to melt the ice.
I’m not sure how to estimate the volume or mass of ocean water that would be heated, since only the surface layer warms. If the temperature gradient goes rapidly down to 2C about 200 m below the surface and the area of the ocean surface is 5.1×10^14 square meters, then the surface layer would be about 10^17 cubic meters at about 10^3 kg/m3 density, thus ~10^20 kg. The heat capacity is about 4×10^3 J/kg-K, so for each degree of warming, you add 4×10^23 J to the surface of the ocean. For a 4 degree rise, that’s 1.6×10^24 J
In other words, the heat added to the oceans to raise the temperature of the atmosphere is a couple of orders of magnitude greater than the heat stored in the atmosphere itself.
Accepting your number of 1.36×10^25 J to melt all the ice, we ought to be able to melt around 12% of the ice cap, and that certainly would cause some SLR on the order of 8 meters I reckon.
But it’s nonsense to think that there could be any physical mechanism to move all that heat to Antarctica, so I’m definitely not arguing that there is any risk of this happening. I’m just saying that the CAGW faithful are not going to be moved by your sermon.
I would hasten to say, don’t trust my math or my science!
Rich,
Thanks for your good points. I wanted to say more – but felt I already had a long post and wanted to take this in smaller chunks based upon engagement. My goal is to try to inject some basic scientific sanity to the Alarmist Narrative the public (largely not technical) is fed. A large plank in the Narrative is “all of the ice melting” – or “a lot” of the ice melting such that we lose cities to floods – and the suggestion is that this could happen suddenly or in a short time from now. The range of possibilities is large: between the current 1mm/yr eustatic rise and the nightmare of tens or hundreds of feet in a lifetime. Without dedicating our lives or careers to studying this, can people with science backgrounds analyze these claims for sanity? Analyze it not to “drain” the subject and resolve the issue to 3 significant figures – but determine which scenarios are even plausible. Let me work my way to your points by developing the ideas a bit more…
The Narrative often focuses on the 4C rise this century – so I started by using that and making some assumptions around it for the analysis. I don’t like how climate science operates but I use what it offers and try to inject something into it that I think is more rational. I contend that climate science is on the wrong track in general because it transacts in temperature. The metric should be energy in Joules – not temperature in degrees. The science should aim to determine the net increase or decrease of energy in the Earth’s “Joule Bank” – and know which “accounts” (atmosphere, sea, ice) this energy is being distributed. As you might know, even in an adiabatic system (where no net energy enters or leaves the system) we can see warming or cooling of the atmosphere and seas and increase or decrease of ice mass. The energy on Earth is distributed over a wide range of temperatures and stored in currents that are in constant motion – at least with air and water. Evaporation of sea water at the equator trades energy between the air and water. This water being deposited as snow/ice at the poles transfers energy between the water and the air. Where a lot of ice is being made, the air will come away warmer. Where it is melting the air will come away cooler. So, we can see temperature changes and other effects without any net change in energy in the system.
The Narrative largely pivots around ice melting – since that offers the most potential for catastrophe. So, my assessment looks at the energy contained in the ice (below 0C solid) vs. the energy contained in the atmosphere and the oceans above 0C. This is the framework. Assumptions can be tweaked around this to see if more valuable insights can be obtained. I already presented the atmosphere and ice. Here is my assessment of the oceans:
Assumptions: 1.4×10^21 kg ocean mass, average temperature of 3C and specific heat of 3,993 J/kg/C. This yields 1.68×10^25 J above 0C.
Putting it together (along with a normalized value to the Atmosphere):
Source Energy (J) Normalized
Atmosphere: 1.45×10^22 J 1
Ice 1.36×10^25 J 935
Oceans 1.68×10^25 J 1,157
So, all of the energy in the atmosphere can barely affect the ice. The oceans have enough energy to melt all of the ice and a bit more, but to do so would bring the oceans very close to 0C.
Of course – and this is the important thing – there is no plausible scenario that can cycle any significant amount of the energy in either the atmosphere or the oceans to the ice. What we really need to know is how much energy is going into the “Joule Bank” every day (or year) as a result of CO2 driven heating – or from whatever the cause is. We are not given this. We get the 4C rise in 100 years story. You point out and I agree this won’t happen in isolation – meaning the seas will warm as well. But we can look at what possible impact that additional 4C can have on the ice. We can assume the Joule Bank gets enough energy in 100 years to raise the temperature 4C. So, I work with this information knowing it is not the full picture – but to flush it out as very weak and not able to produce catastrophe.
Now on to your point(s): what about the oceans? Neither you nor I can resolve that entirely, but we can do some analysis based upon reasoned assumptions. A quantity of energy that can raise the atmosphere by 1C can raise the average ocean temperature by 0.0003C. My assumption is that the energy is stored in the entire mass of the oceans. If you prefer to assume it only gets stored in the upper 200m that is another valid way to approach it. The temperature change will be greater since the mass is less, but the number of Joules of energy stored will be the same.
So how much does the temperature of the ocean rise relative to atmosphere temperature rise? I don’t know. Maybe someone reading can jump in and add to this. For a coarse assessment, I’m not sure it matters. If the atmosphere will rise 4C in 100 years per IPCC, then assume the same energy goes into the oceans. Assume 3x goes into the oceans if you prefer. Then the 4C from the atmosphere could melt 1.4 inches of ice in 100 years and the energy from the oceans could melt another 3 x 1.4 in = 4.2 inches for a total of under 6 inches in 100 years. This assumes that energy all gets transferred to the ice and the transfer goes to fully melting some quantity of ice – not just making it less cold.
Feel free to play with the assumptions. You can see that it is difficult to get to a catastrophic scenario, unless we have some big errors in the assumptions. What is the storage ratio between ocean and atmosphere for new energy in the system? If the ocean to atmosphere ratio is 200:1 then maybe this needs to be thought over. But so far, I believe I’m taking a series of compounded assumptions that are all very favorable to the Narrative and yet we come away with no path to the catastrophe.
William
Certainly, William, no path to catastrophe because there is no plausible way to transport even a tiny fraction of the heat.
But you seem to be arguing that you can raise the atmospheric temperature by 4 degrees and let the ocean temperature only increase by a tiny amount. If the mechanism is that the atmosphere is heated primarily by the surface (ocean or land) that has absorbed incoming solar radiation and is radiating IR back, then clearly the atmosphere has to be cooler than the surface, not warmer.
I don’t see how to imagine that the lower troposphere will be 4 degrees warmer, but the ocean surface water will not also need to be 4 degrees warmer, at least at the interface. Which means that a huge amount of heat must go into the ocean with its much higher heat capacity compared to the air, in order to put a small amount of heat into the atmosphere and raise its temperature by 4 degrees.
If your “heat bank” contains enough joules to melt all the ice, and I suspect that it does, taking into account the total amount of heat in the ocean that could theoretically be removed by cooling it to just above freezing, then the alarmists are not disarmed by your argument. We’re back to them saying that there is plenty enough heat to melt the icecaps and we’re saying sure but there’s no mechanism to transport the heat.
Our argument must be that the heat can only be transferred by mass transport in contact with the ice. When the ice is insulated from any contact with ocean currents by sitting on top of a continent, and there is far less insolation than is lost by radiation, that is a recipe for a permanent ice cap. It would not be the same if the south pole had no continent. Then there would necessarily be some kind of ocean current transporting heat.
Maybe I’m a pessimist by nature, but I don’t think it is possible to persuade the CAGW faithful that their dogmas are wrong based on reason. It’s hopeless to get them to see that they need to assume unrealistic things in order to get the results they fear. They do not test their theories with observation and adjust their theories. They proceed from the conclusion that their theory of doom is a given and then assume ever more implausible explanations for why the observations are wrong because the theory has to be right. “This apparent evidence of an impending ice age is entirely consistent with a warming climate, don’t let your lying eyes fool you!”
Sorry Rich (and All) – my table didn’t format properly. Let me try again.
Rich,
I’m going to try to address all of your points – thanks for the challenge. I’m using average temperatures because that is how Climate Alarmism is presented to us. I can use it nicely and translate this to energy in Joules. Using energy, we can stay at a high level without getting into the weeds. In reality, the physical phenomenon never operates according to the averages – the behavior is according to the instantaneous variable values at a localized or regional point. You can find all over the world, every day, the condition that the air above the ocean is warmer than the water and you can find the opposite. I’m trying to not get lost in the very complex details of how the energy moves, and instead look at the energy in bulk – without sacrificing the accuracy of the result. When I say accuracy, in this case I mean if I assert that the net possible melting is small by doing the bulk energy analysis then I’m expecting it to hold up to scrutiny of a more detailed analysis that takes all of the complex processes and specific thermodynamics into consideration.
In my previous post I use the example of the following over the next 100 years: 3 units of new energy goes to the oceans and 1 unit to the atmosphere – with all 4 units being equal in Joules. 1 unit raises the average temperature of the atmosphere by 4C or the average temperature of the oceans by 0.0003C. In this example the atmosphere warms by 4C and the oceans warm by 4 x 0.0003C or 0.0012C. It is exactly the higher heat capacity you mention that allows the heat energy to be absorbed with less movement of temperature. At the detail level maybe the top 2 inches of water gets much hotter and this will then support the physics of the more complex mechanisms you mention. But the beauty of this approach (I think – and hope) is that it doesn’t really matter how the energy gets distributed in the water with its corresponding temperature effect. Determine the mass of the ocean water you want to see affected in this model and apply the energy to it to get the temperature you would expect. The key is just knowing the amount of new energy stored in the system (“Joule Bank”).
This approach is meant to examine the future Alarmist Narrative catastrophes with respect to the conditions we have now and examine the changes feared in the Narrative. Today we have an average temperature of the air and oceans and we have a certain amount of ice. Some amount of ice has been melting for thousands of years – and we can figure out what has happened roughly over the past 100 years. We can look at the forecasted rise in average atmospheric temperature and average ocean temperature. I just want to use what the IPCC forecasts for example. The point is to use their numbers and then show how the scenarios they fear can’t happen with their numbers. Unfortunately, I can’t find any forecasts for ocean temperature rise! Maybe I need to look harder. Usually we just get a digested figure stating a sea level rise. Lacking the information, I’m thinking about what a reasonable storage ratio is between ocean and air for new energy entering the system. Even at 10:1, using the 4C figure for atmosphere, then it translates to under 16 inches sea level rise in 100 years. That is about double the past 100 years and is based upon the completely absurd assumptions that all of this extra energy exchanges with ice – not just to make it less cold but to melt it.
Some Alarmists are hardened in their views. I don’t do this with the expectation of reaching those people. I hope to be able to reach people who are reasonable. On this forum there are a lot of strong arguments (for and against) – but in general most media presented rebuttals of the Narrative are extremely weak. I wouldn’t mind being an arms merchant for those who get in front of the camera. So, I look for better arguments that are scientific but simpler.
We are constantly quoted incremental Watts/m^2 (Power) of retained solar heat due to CO2 concentration. We just need climate scientists to integrate this over time and area … essentially give us the energy retained – not the power. Unfortunately, the incremental power has a very wide range of estimates – essentially a large range of uncertainty. So, they don’t really know. (I’ll take it as an action item to try to calculate the additional energy from their power estimates… but maybe not in time for this thread.)
There has got to be a way to rule in or out these catastrophic scenarios – because I’m tired of people trying to scare me with them!
Does this explanation help my case in your eyes?
William
Meanwhile, back at the ranch, the IPCC has chosen the next lot of purported scientists to maintain the CO2 Meme, naively or otherwise, for the coming AR6.
The output, of course, will be driven by the army of political activists.
Just adding enough heat to melt ice isn’t going to do the job. The average temp in Antarctica is about -58 F (-100F in winter), so you’re going to have to warm up the arctic by 58 + 32 = 90 degrees just to get to the melting point of ice.
you should talk in C or K C=(5/9) *(F-32) 1delta C =1delta K K = C+273
i should have separated the sections
you should talk in C or K; ;;;;;;;; C=(5/9) *(F-32) ;;;;;;;;;;;;;;;;;1delta C =1delta K ;;;;;;;;;;;;K = C+273
If you read my complete text, you will see that I’ve addressed that in the assumptions.
Antarctica averages 2500 meters in elevation. The lapse rate means it is on average at least 15 C – 20 C colder than sea level temperatures. The average temp of the earth is 15 C at sea level. Much lower at the piles.
Meaning that Antarctica cannot melt no matter how much heat you throw at it. The lapse rate will simply wick the excess heat back into the atmosphere and redistribute is around the globe.
So no one is going to drown because of sea level rise??????????????????????????????
The majority of people drowning in Norway are grown men with their trouser fly open (and alcohol in their blood stream……)
Depends, if the sea level rises a few millimetres a year most people would be able to avoid drowning unless they plan to tie themselves to a post with the sea just below their bottom lip, but they are likely to die from exposure and lack of food and water first.
Harry, would that be low tide or high tide?
Considering the Antarctic mountains proxy, it was 20c warmer and the ice sheet is said to be stable at that time, if a valid reconstruction, and valid stable ice sheet, it would take some doing, even setting off nukes there would not melt it, you would need the entire US arsenal, 6800 warheads, maybe the 7000 Russian ones too?, but post explosions all that melted ice would create one heck of a cloud system on this planet and cause the sheet to be bigger than when you started trying to melt it maybe.
Any other less catastrophic way we might do it could take 10s of thousands of years, or longer
“Can Humans Melt the Antarctic Icecap?”
Maybe, but we’ll never do it if we don’t try.
Ice cores show that historically, CO2 emissions rose several hundred years after a warming event. The CO2 came from warming water. That seems to indicate that an increase in CO2 cannot warm ocean water fast enough to produce the claimed changes on this short a timescale.
Judge Alsup got close to this in his question 5 in the California Kid’s Climate lawsuit. 5 Apart from CO2, what happens to the collective heat from tail pipe exhausts, engine radiators, and all other heat from combustion of fossil fuels? How, if at all, does this collective heat contribute to warming of the atmosphere?
It doesn’t (except UHI), and no warmunist claim it does (well, I shouldn’t write “none”, as for sure some nutty, physics illiterate does, but you get the idea).
Dr. Walter Orr Roberts, President of the University Corporation for Atmospheric Research and the American Association for the Advancement of Science, 1972:
“I suspect that one of the very most important studies over the next two or three decades will be the study of what the added heat pollution, the added dust burden, to the atmosphere by man’s activities, what that actually does or will do to the climates.”
Survival of Spaceship Earth – featuring Maurice Strong and friends, with no guest appearance from carbon dioxide.
If I were to melt the Antarctica Ice cap, because, … well… whatever reason…
I won’t do it that way.
I would dump it in the sea, and have the ocean melt it. So I would just push it there, by a combination of physical and chemical methods (chemists, because some lubrication would help a lot)
I would use the potential energy of this water/ice falling, as most of it is hundred of meter higher than the ocean. This potential energy is magnitude too low to melt the ice (9.81 J par kg and meter of chute, even a 1 km chute gives only 9.8 10^3 J) , but well enough to help pushing it into sea.
I would use current and wind energy to tract iceberg away from antarctica. No need to have ice go to a precise point, we just need it to disperse (beware, ships, we don’t care about you,…)
etc.
This would be a mega-mega-project; and would cost tremendous amount of money and nuisances, but won’t require all the energy of the human world to be done.
Now, It of course won’t happen all by itself, not even if CO2 were to multiply by 10
*blinks* Explaining wind is hard? Really? Tell them to get a fishbowl, a tennis ball, a dowel rod, some water, and some food coloring. Ram dowel rod through center of tennis ball. Fill bowl with water. Insert tennis ball in bowl. Start spinning. Add drops of food coloring. Boom, simple and obvious representation of wind against the surface of the earth. Things like temperature variance, density and pressure changes, and cloud albedo obviously add additional chaos to the system, but the concept remains the same.
You are talking about a continental system of land, shelf ice, and sea ice larger than all other land areas south of the equator. Combined. Your simplistic fishbowl is not convincing.
I actually think that climate change is highly debatable, but even I can see the flaw in your argument.
The climate change argument is NOT that humans are creating energy that is melting the polar ice caps. The climate change argument is that human pollution is increasing the heating efficiency of the Sun on the earth. As you obviously know, purely from an energy perspective, the sun is more than powerful enough to melt the polar ice caps.
Yes, the energy does come from the sun, but the amount of energy in the atmosphere is a known value, within the limits of measurement.
How long it would take that energy to melt the Antarctic ice cap is a value that can be calculated.
As has been done here. You have not pointed out a valid flaw.
After a very short Google search on “Antarctica” in the news this morning:
Antarctica Continues To Melt In Winter Despite Subzero Winter Temperatures
Complete with diagrams:
http://cdn.iflscience.com/images/bf42abaf-aad2-53a5-8e6d-3d5e576e03ba/content-1523903960-foehn-effect.jpg
And the ever present warning about sea level rise:
Are you a complete idiot and can not read. The process occurs only on the backside of mountains and it could add to destabilizing areas that already have issues no problem. What they won’t do is melt the entire continent of Antarctica or break it up that only happens in the CAGW comedy channel.
Who are you calling an idiot?
I posted that article here because it is on topic about Antarctica melting.
The headline:
Antarctica Continues To Melt In Winter Despite Subzero Winter Temperatures
is bullshit.
No, it doesn’t melt, but it does sublimate, which ice does even on Mars. Melting is actually a rather minor process in Antarctica and completely insignificant on a continental scale. The significant process is calving.
At no point have they suggested the entire continent will melt by the process. You would have similar titles like “USA mainland warmer this month” are you seriously going to read that as each and every point on each and every day of the month was warmer. The statement requires the reader to use some common sense.
The “Foehn effect” (or chinook wind) sometimes occurs in temperate areas with a high, steep mountain range crosswise to the prevailing wind, such as the Cascades in Washington State or the Pyrenees between Spain and France (for winds from the south).
This doesn’t apply to Antarctica, because the mountain ranges in Antarctica are covered by a high, wide ice cap which forms a wide plateau over Antarctica. The prevailing winds around Antarctica are generally out of the west, forming a circle roughly parallel to the coast, so there wouldn’t be a Foehn effect except possibly on the lee (east) side of the Antarctic peninsula. Over the Antarctic mainland, the plateau is too wide and too flat to cause much compression and warming of air flowing northward from the South Pole along a meridian. Besides, air flowing from the South Pole is extremely cold to begin with, and it wouldn’t receive much solar heating at about 70 degrees south latitude when it gets to the coast!
the Foehn effect doesn’t care if the climate is temperate or not, and will happen just as well under tropics or in polar region. All is required is moist air carried by wind up and down a significant rise of land. continental Antarctic obviously doesn’t qualify (no moist air, to begin with), but antarctic peninsula does, so you should expect Foehn effect at some place there.
The melting of the caps is entirely possibly; it just
depends how many Mann eruptions earthlings will have.
Had this discussion been about Martian icecaps it would have been a lot more interesting IMHO.
I don’t think anybody who has done calculations in this post is correct. The point about human induced global warming isn’t that we send a lot heat into the ice sheets – it’s that we send a lot of CO2 into the atmosphere. Since that CO2 is well mixed with the other gases, the entire atmosphere acts like a blanket to hold heat in. The value of that extra heat is about 2 Watts per square meter. Here is the calculation I come up with:
Total extra heat due to infrared absorption =
[ 2 Joules / second / m^2 ]
[3 x 10^7 seconds/year ] x
3.14 x (6.3 x 10^6)^2 [area of Earth as seen by Sun = 1.2x 10^14 m^2]
= 6 x 10^23 Joules per year
So, yes, mankind can melt the polar ice sheets.
Erik
I don’t think your calculation is any better.
IF (big if…) world’s surface gets 2W/m² average, tropics will get maybe 3W/m² will, while polar region will get like 0.2W: that’s because, while polar region account for ~1/10 of earth surface, they only ~1% of sunrays
And that’s only crude calculation, reality is even harsher to your hypothesis.
In fact, per IPCC calculation, “global warming” down at surface level translates into “global cooling” up in the atmosphere, that is in the region of atmosphere which at 255K or lower temperature… which includes surface in polar region. So IF IPCC were right, then it there would actually NEGATIVE “forcing” over Antarctica … and in arctic as well.
“6 x 10^23 Joules per year
So, yes, mankind can melt the polar ice sheets”
Not correct, the total extra energy for this example at 2 W/m2 is 1.6 x 10^19 Joules per year. 2 W/m2 is not correct either because around 3.7 W/m2 at TOA and around 1 W/m2 at sea level. This doesn’t even take into account how much solar energy reaches the polar regions being about 100 times less.
That is no where near enough to melt the ice at 1.6 x 10^17 Joules per year. At 1W/m2 this value further declines to 8.02 x10^16 Joules per year.
The area of Earth is 5.1 x 10^11 m2, half that the sun radiates being 2.55 10^11 m2.
Finally, latent heat may well be more than 1 J per second per square meter, so almost cancels this value out if not at all.
1.6 x 10^17 Joules per year represents a value 34285941 (34 million+) times smaller than solar energy.
I have made an error above so corrected it below because it especially changes all the corresponding values.
The area of Earth is 5.1 x 10^14 m2, half that the sun radiates being 2.55 x 10^14 m2.
The total extra energy for this example at 2 W/m2 is 1.6 x 10^22 Joules per year.
Added not shown before, the area of polar regions is around 9.6% of the Earth’s surface covering 1.54 x 10^21 Joules per year.
One hundred times less solar energy becomes 1.54 x 10^19 Joules per year that is still orders smaller than required for slight melting of a 1 cubic km glacier at zero degrees centigrade. With the continent well below zero centigrade in Summer there is no melting from this increase in energy.
Therefore 1.54 x 10^19 Joules per year represents a value 347145.2 (347 thousand+) times smaller than solar energy.
BUT, this value becomes 7.70 x 10^18 Joules per year at 1 W/m2. (714290 times smaller than solar energy)
A neat educational exercise, but I’m not sure that it’s addressing the correct problem. As i understand it, the concern is that if all the water currently locked up in land-based Antarctic ice masses were transferred to the world’s oceans, that would raise the sea level substantially.
Now the problem that the author tackles is to calculate the heat required to transfer this mass by turning the ice into liquid water so that the water would flow off the land and into the ocean.
However, there are alternative ways of moving the ice masses, especially that of reducing the friction at the base of the ice masses (by ground level melting at the base of the ice masses) along with fragmenting the ice blocks so that they could slide off the elevated land and enter the sea and move away to become free-floating icebergs.
As Archimedes famously recognized, such floating icebergs (as a first order approximation) would raise the sea level the same as if all the ice were turned into liquid water (ignoring, for the moment second order effects such as that consequent cooling of the ocean water would initially cause some compensatory lowering of the sea level due to volume contraction as the water approaches its maximum density at 4 degrees C, before its volume starts expanding again).
And obviously, it would take much less heat to move ice to the ocean in mostly ice form, especially in conjunction with strategic location of such heating, most likely through volcanic activity, that could speed up the transfer to a feasible time period.
Same for the “danger” of Greenland land-based ice sheets.
However, this doesn’t help the CO2 alarmists’ crusade, since mechanisms such as volcanism have zero to do with atmospheric CO2 elevations. Their only hope of relevance is if they could show that the amount of surface melting from the tiny increases in surface temperatures arising over decades from possible CO2 increases could create drastic lubrication effects. Good luck with that.
Seems to me that albedo changes from deposition of carbon particles would be a far more potent actor in high-latitudes surface melting than fractions of degree over decades changes in “global” surface temperature. But the political and financial benefit of such retargeting of efforts for the alarmists would drastically reduce the money from “villains” like the U.S. and Europe that have been lubricating their activities up to now.
Nonetheless, a worthwhile object lesson to help people better appreciate large numbers.