Merged Global Warming Discussion II: Heated Conversation
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r-j
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and the amount of salt when the ice freezes is the same
the volume of sea water decreased by the volume of ice as it froze
the saliity increased when the ice formed
the higher the salinity, the higher the density of the sea water
the higher the density of the sea water, the the less volume it has
It's simple because all the things happen in both directions, and no salt or water is lost or gained
I can't believe anyone doesn't know this. Salt water or fresh, it does not matter, ice freezing does not change the level of the water. You can do an experiment in your own home to prove this beyond any doubt.
r-j
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If ice shelves raise the sea level by melting, then the sea decreased by the exact same amount when the water vapor left the ocean. But that happened a long time ago.
So of course to us it will certainly seem like sea level rise. But sea ice, which forms directly from the ocean, will not change the sea level. Unless of course it all melted and no new ice formed.
There are two different things here. I am objecting to the experiment on the blog, and the very idea that sea ice melting will raise the sea level. If you look at it that way, then it lowered the sea level when it formed. The two things balance.
So of course to us it will certainly seem like sea level rise. But sea ice, which forms directly from the ocean, will not change the sea level. Unless of course it all melted and no new ice formed.
There are two different things here. I am objecting to the experiment on the blog, and the very idea that sea ice melting will raise the sea level. If you look at it that way, then it lowered the sea level when it formed. The two things balance.
a_unique_person
Director of Hatcheries and Conditioning
aleCcowaN
imperfecto del subjuntivo
... and the former ice becomes salty water again
.Y'all can follow the rest of the story -and its place in the big picture- by looking into "halosteric component of steric sea level change". The last 30 years in figure 7 of this basic resource, may explain how the loss of sea ice and the new fresh water coming from melting glaciers and continental ice-shelves, risen sea level?
You may find tiny ups and downs, according to where the saltier water goes.
I propose you to take, say 1,000 km3 of sea ice, 0% salt, only 890 km3 of it below sea surface, and 100,000 km3 of sea water, 3.5% salt, all at 0°C, all at sea level -for the sake of a straightforward calculation-, and crunch the final variation of volume and sea level -remember 110 km3 of ice were above sea level-. You only need a table or figure of seawater densities at 0°C when salinity varies.
Let me know your conclusions and we'll take it from there.
aleCcowaN
imperfecto del subjuntivo
following previous post.
You have to arrive to some conclusion like this one, but not the same. Then we'll take it from there. But, do we agree we're seeking the big picture here? or are we going to loop around tiny local and temporal changes?
As for the yet not clearly explained 9 mm. There's still a long way to go, but I'm giving a sneak peak: it goes in the direction of this old figure I used here one or two years ago and the evident structure it shows
Now, I have to say "see y'all later" for several hours. It's Friday and I have a lot of errands and whatnot in "el microlombo" -mix of microcentro (core downtown, "The City") and quilombo (formerly a low-level brothel-like joint, becoming "a big chaotic mess" in modern language). I'll be back as soon I am freed from the chaos.
You have to arrive to some conclusion like this one, but not the same. Then we'll take it from there. But, do we agree we're seeking the big picture here? or are we going to loop around tiny local and temporal changes?
As for the yet not clearly explained 9 mm. There's still a long way to go, but I'm giving a sneak peak: it goes in the direction of this old figure I used here one or two years ago and the evident structure it shows
Now, I have to say "see y'all later" for several hours. It's Friday and I have a lot of errands and whatnot in "el microlombo" -mix of microcentro (core downtown, "The City") and quilombo (formerly a low-level brothel-like joint, becoming "a big chaotic mess" in modern language). I'll be back as soon I am freed from the chaos.
r-j
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The original parameters were clear.
The water level does not change, if compared to the original water level.
If you measure the water level after the ice has fored, from sea water, it's not scientific. You have to measure before and after, and the ice has to come from the sea water it is floating in. Not ice shelves, ice sheets or glaciers dropping into it.
If the sea ice formed in recent history, there is no change at all. As the ice forms, it lowers the sea level by the exact same amount it raises it later.
You can do an experiment and prove this for yourself. Claiming sea ice meting will raise the sea level is not true. Any rise is countered by the exact same lowering when the ice forms.
If it's salt water, and the ice was made from the slat water, it will slightly rise. But, it also slightly dropped when the ice formed. If you don't put a mark on the glass before you freeze some of the water, you will miss that fact.
Which is what the SS blog forgot to do.
Exactly. If you drop a fresh ice cube into the salt water in the glass, it's not scientific.
aleCcowaN
imperfecto del subjuntivo
[Íñigo Montoya]
By the way, I finally found the link to the handbook on seawater properties. This is a table on its thermal expansion
To use this available figure -a depth that is a classic boundary between ocean layers-
Let's imagine that heat from the North Atlantic is moved from the warm areas not far from the shores of Florida, Georgia and the Carolinas to a much colder area, like those areas North-east of the Amazon River mouth. One body of water cools from 13 to 12°C, and the other one -as large as the first one- warms from 5.5 to 6.5°C. Looking at the table, with the aid of interpolation -salinity 3.5% constant, for the sake of simplicity-, we have a coefficient of 200 millionths for the warm body of water and 137 for the cool one. That means, a 100-metre layer contracts 20mm while the other one expands 13.7mm. That is, provided our "ocean" is made just of these two layers and areas, its level drops 3.15mm. And we are just talking of water at the same depth and accounted together.
Roughly, if heat in the North Atlantic moves towards the Equator in levels like -300m, -700m or -1500m, then the sea level will experience a drop worldwide. On the contrary, if heat moves northwards, the sea level will rise.
This is not written in stone. This is one of hundred of possible modes playing at the same time. But it's easy to see how heat storage in the ocean can affect greatly sea levels without necessary implying energy exchange. Even more, if in the problem above we lost a third of the heat content moved, the sea level will remain constant, and even better, if we added a third to that heat moved, the sea level would still drop a bit.
That was the point of that question. To introduce this variable, mostly forgotten in denialist vs warmer debate, as many other variables are. To discriminate the origin of a sea level drop or raise we have to use ARGO, not only Australian floods -that indeed contributed to the sea level to drop-.
About those 9mm, I wouldn't know for sure. My own calculations with ARGO stick to southern oceans. Those with a reasonable error margin, just to the Southern Atlantic. In such part I found a level drop of almost 2mm without even a change in heat content, as the so called "temperature pause" is mostly made of heat being ditched in the seas and moving from the North Atlantic and Indian to the Pacific. Mostly, because temperatures continue to go up.
By the way, two more interesting questions:
Did you detected in the map that "structure" I told?
At that -700m level, why are so hot those waters between Puerto Rico, Florida, Virginia or New York by the West, and Spain, Portugal and Morocco by the East. Hotter than almost any other place in the ocean, at that level?
[/Íñigo Montoya]
By the way, I finally found the link to the handbook on seawater properties. This is a table on its thermal expansion
To use this available figure -a depth that is a classic boundary between ocean layers-
Let's imagine that heat from the North Atlantic is moved from the warm areas not far from the shores of Florida, Georgia and the Carolinas to a much colder area, like those areas North-east of the Amazon River mouth. One body of water cools from 13 to 12°C, and the other one -as large as the first one- warms from 5.5 to 6.5°C. Looking at the table, with the aid of interpolation -salinity 3.5% constant, for the sake of simplicity-, we have a coefficient of 200 millionths for the warm body of water and 137 for the cool one. That means, a 100-metre layer contracts 20mm while the other one expands 13.7mm. That is, provided our "ocean" is made just of these two layers and areas, its level drops 3.15mm. And we are just talking of water at the same depth and accounted together.
Roughly, if heat in the North Atlantic moves towards the Equator in levels like -300m, -700m or -1500m, then the sea level will experience a drop worldwide. On the contrary, if heat moves northwards, the sea level will rise.
This is not written in stone. This is one of hundred of possible modes playing at the same time. But it's easy to see how heat storage in the ocean can affect greatly sea levels without necessary implying energy exchange. Even more, if in the problem above we lost a third of the heat content moved, the sea level will remain constant, and even better, if we added a third to that heat moved, the sea level would still drop a bit.
That was the point of that question. To introduce this variable, mostly forgotten in denialist vs warmer debate, as many other variables are. To discriminate the origin of a sea level drop or raise we have to use ARGO, not only Australian floods -that indeed contributed to the sea level to drop-.
About those 9mm, I wouldn't know for sure. My own calculations with ARGO stick to southern oceans. Those with a reasonable error margin, just to the Southern Atlantic. In such part I found a level drop of almost 2mm without even a change in heat content, as the so called "temperature pause" is mostly made of heat being ditched in the seas and moving from the North Atlantic and Indian to the Pacific. Mostly, because temperatures continue to go up.
By the way, two more interesting questions:
Did you detected in the map that "structure" I told?
At that -700m level, why are so hot those waters between Puerto Rico, Florida, Virginia or New York by the West, and Spain, Portugal and Morocco by the East. Hotter than almost any other place in the ocean, at that level?
aleCcowaN
imperfecto del subjuntivo
I was playing with this interesting tool to watch what's happening in the neighbourhood. Use your mouse creatively, and click on the menu (earth)
a_unique_person
Director of Hatcheries and Conditioning
A bit above my pay grade, but I think I get the gist of it.
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aleCcowaN
imperfecto del subjuntivo
Don't sell yourself short! Share your ideas. The worst that can happen is all of us learning something.
About da'structure, I was mesmerized watching part of it at work with our new toy. Also in my backyard. Aren't these guys geniuses?
a_unique_person
Director of Hatcheries and Conditioning
That is truly amazing.
a_unique_person
Director of Hatcheries and Conditioning
The response of the ocean sea level to the contained heat is not linear. As you move heat around within the ocean, you will then get the total sea level rising and falling, even though the total heat has not decreased.
aleCcowaN
imperfecto del subjuntivo
The response of the ocean sea level to the contained heat is not linear. As you move heat around within the ocean, you will then get the total sea level rising and falling, even though the total heat has not decreased.
Quite right. This is not "the" factor, but an important factor that I think none of you -and other people rowing everywhere against the dark streams of denialism- got. Part of the "hidden climate science", the rest of the puzzle that is not discussed in the web or in the telly because denialists haven't dug their claws on it.
But "da'structure" is something a bit different that is visible in the map. And why it exists and how may it work relates with the other question about the super hot North Atlantic, which doesn't look the hottest in the surface but transversally, it is, giving countries that lay at the same latitude of Vladivostok and Southern Siberia, like Southern France or Spain, the fame of being calienteh.
macdoc
Philosopher
Consequences unfold
Britain floats off to the tropics...
http://www.telegraph.co.uk/earth/10883492/UK-sees-a-fortnights-worth-of-rain-in-one-hour.html
Those are Cairns Australia kinda numbers...it's the intensity numbers that are getting crazy high....commonplace in the tropics....those numbers are insane for temperate climes.
this is a follow up to the drowning of Eastern Europe last month...
and reminds me of the intensity of what hit central Europe last year with the Danube hitting a 500 year high water mark.
blocking pattern again...California Ridiculous Reslient Ridge
http://www.weatherwest.com/archives/tag/ridiculously-resilient-ridge
and our fun winter vortex.
We just got brushed by that particular rainfail event in Europe in 2013 and totally insane levels of rain even if we were used to it from tropical Australia. Friends whose house we rented had never seen the river near the house so high
Britain floats off to the tropics...
more
http://www.telegraph.co.uk/earth/10883492/UK-sees-a-fortnights-worth-of-rain-in-one-hour.html
Those are Cairns Australia kinda numbers...it's the intensity numbers that are getting crazy high....commonplace in the tropics....those numbers are insane for temperate climes.
this is a follow up to the drowning of Eastern Europe last month...
and reminds me of the intensity of what hit central Europe last year with the Danube hitting a 500 year high water mark.
http://en.wikipedia.org/wiki/2013_European_floods
blocking pattern again...California Ridiculous Reslient Ridge
http://www.weatherwest.com/archives/tag/ridiculously-resilient-ridge
and our fun winter vortex.
We just got brushed by that particular rainfail event in Europe in 2013 and totally insane levels of rain even if we were used to it from tropical Australia. Friends whose house we rented had never seen the river near the house so high
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macdoc
Philosopher
Now THAT is a big number - 10 cu km of ice lost in a MONTH!!!
more
http://robertscribbler.wordpress.com
more
http://robertscribbler.wordpress.com
aleCcowaN
imperfecto del subjuntivo
So little? Why is this a piece of news?
Glaciers and large continental ice packs contribute to the sea level rise some 450 cubic kilometres a year, that is an average of 9 cubic kilometres a week, with peaks during both boreal and austral summers. This is just "contribution to sea level rise", as actual melting rates peak many times those figures as most of the ice is going to be replenish during the cold seasons.
Ice in floating shelves like Ross, Larsen, Fischer-Ronne, Amery, Wilkins, and many more, including shelf-like ice floating in Greenland's fiords and nearby, is not going to contribute to sea level rise -read further-, but it is also lost at a comparable rate. These events are not so seasonal as they involve ice structures with structural features, and they develop with a chaotic component, so exactly like earthquakes, but less predictable than simple melting. These events are also important, now and then -like an earthquake-. Petermann Glacier lost some 250 square kilometres (30 cubic kilometres?) of ice, all at one, back in 2010 or 2011. Back in 2007?2008? a much much much larger chunk of ice was broken in the Antarctic Peninsula, but fortunately most of it moved and stranded elsewhere, though the definitive loss was much important.
Jakobshavn Glacier losses at least 40 cubic kilometres of ice a year. Why is this specially relevant? Was there any doubt global warming continues? Is there any doubt the Arctic gets most of its heat from lower latitudes, even during July? Was it necessary that story of tropical warm waters reaching the ice and sneakily melting it from below, sort of a thermal McCarthyism?
Can we put all this ice ... sheet thing to a rest?
Let's solve the problem.
We have a sea area of one million square kilometres and 100 metres deep, that is, 100,000 cubic kilometres of water and a sea level of 100 metres. That water is all at 0°C and it all has a salinity of 35 grams per litre. We have floating there a volume of 1,000 cubic kilometres of ice, free of brine or any salt content, and also at even 0°C. Some heat is added, the exact heat to melt the ice and have it all at 0°C. What happens with our 100-metre level?
Let's start. Fresh water density: (pure water) Ice density at 0°C : 0.9167 g/cm3 (source). Sea water density at 0°C, 1 atm and salinity of 35 g/litre:
I'm using the approximation given by this document offered by MIT faculty through MIT Open Access Articles: http://dspace.mit.edu/handle/1721.1/69157 , formula (6) page 48 (in print,49 in downloadable pdf). It's a little old, but it has a maximum error of 1/10,000th, that is not in the part of the range we are using, and even better, it has a web version in this page: http://www.csgnetwork.com/h2odenscalc.html . For those sceptics like me, you are encourage to read the code and verify it follows that formula. Here's the chunk of javascript, for those sceptic but lazy:
function rhoscalc (rho,conc,temp) { // temp and conc dependent density
var rhos, A, B, temp;
A = 0.824493 - 0.0040899*temp + 0.000076438*Math.pow(temp,2)-0.00000082467*Math.pow(temp,3) + 0.0000000053675*Math.pow(temp,4);
B = -0.005724 + 0.00010227*temp - 0.0000016546*Math.pow(temp,2);
rhos = rho + A*conc + B*Math.pow(conc,(3/2)) + 0.00048314*Math.pow(conc,2);
return rhos;
}
For our sea ice, it gives 1,028.131 kg/m3. var rhos, A, B, temp;
A = 0.824493 - 0.0040899*temp + 0.000076438*Math.pow(temp,2)-0.00000082467*Math.pow(temp,3) + 0.0000000053675*Math.pow(temp,4);
B = -0.005724 + 0.00010227*temp - 0.0000016546*Math.pow(temp,2);
rhos = rho + A*conc + B*Math.pow(conc,(3/2)) + 0.00048314*Math.pow(conc,2);
return rhos;
}
So, our ice (1000 km3 *0.9167 g/cm3 = 916.7 GT) must displace 916.7 GT / 1,028.131 kg/m3 = 891.618 km3 of sea water, that means:
We have 891.618 km3 of ice submerged in the sea water; we have 108.382 km3 of ice (1000-891.618) protruding above sea level; we have 99108.382 km3 of sea water (100000-891.618), and that salty water weighs 101,896.4 GT (99108.382 * 1.028131) of which 3468,793 GT are salts (99108.382 * 35/1000) and 98,427.607 GT are water (101896.4-3468.793). Water then totals 99344,307 GT (98427.607+916.7).
All melts, and now we have a mess of 99344.307+3468.793 = 102813.1 GT of sea water with a salinity of 3468.793/102813.1 = 33.739 g per kilogram (and not litre). How do we follow now? By iteration. If it were 33.739 per litre, its density would be -using link above- 1027.113 kg/m3, so, one litre must contain 33.739 g/kg * 1.027113 kg/litre = 34.654 g/litre. Back to the link, the density for that is 1027.852 kg/m3, so 33.739 multiplied by that gives 34.679. Repeating the cycle: 1027.872, 34,679 -round to the same decimal-. Let's check: we have sea water with a salinity of 34.679 g/litre and a density of 1027.872 kg/m3, which means 34.679/1.027872 = 33.739 g of salts per kilogram, the same value we started from.
And here is the question. What's the volume of water? Its 102813.1 GT of sea water divided 1.027872 kg/litre of density, that is 100,025.2 km3, what means, the sea level has risen 25.2 mm. That is for an ice loss of 1,000 km3 and an ocean of one million square kilometres. For an ice loss of 650 and a global ocean of 360, the rise is 25.2*.65/360 = 45 microns a year
Conclusions:
Formation and melting of ice each year drive important seasonal changes in sea level both in the Arctic and Antarctic (we're talking of 15/18,000 km3 of ice in just 6 months) and it even should account for unbalances in ocean currents.
Changes in salinity all around the ocean drive a change of sea level known as its halosteric component that has been in recent years much stronger and opposite in sign to the sea-level change estimated above. In this case, also temperature but mostly the forgotten element, pressure, do this.
The sea level continue to rise about 1.25 mm a year because of the melting of glaciers and ice packs, and this has an upwards trend.
These three elements alone render this conclusion: for any practical end we can dismiss any variation of sea level coming from melting sea ice as irrelevant. The bit "yearly loss of sea ice doesn't contribute to sea level rise" stands.
Uffa! If I added the estimation of sea ice loss from other sources, I would have had a paper with this recommendation: models need to include a yearly variation of 45 microns a year in sea level coming from loss of sea ice. Wait! Some other did it. Rush! We're running out of obvious or irrelevant things to publish!
aleCcowaN
imperfecto del subjuntivo
Take most of my previous post as my protest by example about the waste of time that is allowing ourselves to be lost in trifles. They are trifles because they are mainly offered as disjointed bits of the climate change scenario without any attempt to connect them to the rest of the problem.
When they are blog or press snippets, they're also pathetic, most of the time.
I'm much worried for the lack of answer to this:
The expected answer is the root of every answer in this topic, so, if you fail at it, you're just being throwing leaves and telling you had the tree. Failing to detect that is serious enough.
When they are blog or press snippets, they're also pathetic, most of the time.
I'm much worried for the lack of answer to this:
The expected answer is the root of every answer in this topic, so, if you fail at it, you're just being throwing leaves and telling you had the tree. Failing to detect that is serious enough.
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