Vostok Revisited: More on Iconic Figure #2

By: Dr. Ricky Rood , 5:36 AM GMT on September 17, 2007

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Vostok Revisited: More on Iconic Figure #2


In my previous WU blog, I showed the figure of carbon dioxide (CO2) and temperature from the Vostok ice core.

In the analysis of that figure I wrote: The periodicity is closely correlated with many of the orbital parameters of the Earth and the Sun. As many of you will note, this curve does not establish cause and effect. Further, higher scrutiny shows that the temperature increase begins before the carbon dioxide increase. This combination of the orbital parameters, the change in temperature, and the change in carbon dioxide provides a challenge for understanding. A plausible physical argument can be made that the greenhouse gases modulate, perhaps amplify, the radiative changes associated with the orbital parameters. Much of the change in the carbon dioxide would be associated with changes in ocean biology and chemistry.

I want to return to this analysis and the plausible role of the ocean. Here is a schematic figure that I drew of the ocean and the atmosphere and carbon dioxide. One of things that is most important when starting to examine a problem is to draw a figure.



Figure 1: Carbon dioxide at the ocean-atmosphere interface.

The top of the figure is the atmosphere and the bottom of the figure is the ocean. The wavy line in the middle is the ocean surface. I drew a dark dashed line below the ocean surface to represent the bottom of the mixed layer of the ocean. Like the atmosphere, the layer of the ocean closest to the surface is relatively well mixed. One factor that determines the depth of this layer is the wind speed at the surface of the ocean.

The green arrow labeled CO2 suggests that CO2 is transported back and forth between the ocean and atmosphere. The characteristic that is most important to the direction of the transport is the pressure of CO2. If the pressure of CO2 is higher in the atmosphere than in the ocean, then CO2 is transported into the ocean water. If the pressure of CO2 is lower in the atmosphere than in the ocean, then CO2 comes out of the water into the air. Remember that pressure is related to temperature. There are two other two-way arrows that I have drawn. The arrow labeled "tropics" represents the notion that in the tropics there is generally CO2 going from the ocean to the atmosphere. This is due to the warm ocean water. The arrow labeled "polar" represents the notion that at polar latitudes CO2 goes from the atmosphere to the ocean. This is the average situation.

I have drawn a bunch of arrows in the ocean; these are very important to the climate problem. Once in the ocean, the CO2 is "reactive." First, there is "chemistry," which converts the CO2 into carbonic acid. This effectively removes CO2 from the water, reduces the pressure of CO2, and hence, allows the ocean to take up more CO2. Thus, chemical conversion of CO2 allows the ocean to take up more and more of the atmospheric CO2. This mechanism is often called the "solubility pump," because CO2 is in a solution with ocean water. A consequence of the solubility pump is that the ocean becomes more acidic.

Second, there is biology. CO2 is used by plankton. In combination with calcium, exoskeletons and shells and bones are built. Again, carbon dioxide is removed from the ocean water, the pressure is reduced, and more CO2 can be transported from the air into the water. This is often called the biological pump.

For the sake of clarity, I needed space to draw the "biology" and "chemistry" arrows. The way they are drawn is not meant to represent a relationship to the tropics or the poles. They are just meant to explain what can happen to the CO2 dissolved in the ocean water.

There are two other elements in the figure I want to point out. These are the white arrow at the right of the figure and the artistically drawn cloud-like feature below the "plankton, shells, and bones." The arrow represents the transport of water out of the mixed layer into the deep ocean. This process occurs, primarily, in small regions of the polar oceans and seas. The cloud-like feature represents the "precipitation" of carbon, bound with calcium, as creatures die and sink.

None of the processes I described above go on without impacts or consequences. For instance, the acidity of the ocean will affect the ability of plankton to form their shells. Plus, much of the carbon that is transported down to the bottom of the ocean is slowly transported back to the surface, where it can return to the atmosphere. A small fraction remains as sediment on the bottom and gets incorporated back into the geological compartment of the Earth system. The mechanisms and paths described above are very good starting places.

Why did I go through all of this? Not so long ago many people viewed that the CO2 in the atmosphere would not be much of a problem because of the great capacity of the ocean. Two things: 1) While the capacity is large, there are consequences of putting more carbon into the ocean. 2) It takes a very long time for all of these oceanic processes to catch up with the excess CO2 we are putting into the atmosphere. The ocean might ultimately take it up, but not until there are significant changes to the atmosphere, the weather, the climate.

Back to that issue of the ice-age cycles and the warming starting before the CO2 starts to rise. Go to the figure above. Assume there is some source of warming that is not linked to CO2. If it leads to the ocean warming, then the CO2 in the ocean will start to be released into the atmosphere. The ocean will be less able to take up CO2. There will be transport of CO2 to the atmosphere. Once the CO2 is released into the atmosphere, it will make things warmer, and that will lead to more CO2 being released from the ocean. If the warming starts after a long period of cold, then there will be a lot of CO2 in the ocean to be released. This is a positive feedback. The links provided at the end go to earlier blogs where I have discussed other types of feedbacks. The general idea of the cycling is that the Sun-Earth orbital variability initiates the warming, the CO2 is released from the ocean, the positive feedback loop starts, and then this CO2 warming takes over. Why does it stop? (That's for later.)

Going back to the figure of the cycles from the last blog: What is different now than in the past few cycles? Plus what is the role of ice, especially sea ice.

r


Warm Snow

Reflections

Absorbing

Clouds Cool and Warm

Cooling Aerosols



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35. CycleForecasting
12:55 PM GMT on September 22, 2007
Ricky, you state that during "the ice-age cycles and the warming starting before the CO2 starts to rise The general idea of the cycling is that the Sun-Earth orbital variability initiates the warming, the CO2 is released from the ocean, the positive feedback loop starts, and then this CO2 warming takes over".

This does sound reasonable as seen in the 100,000-year temperature/CO2 cycles (see Link ).

However, if you look at temperature fluctuations during the shorter term, say 1000-years, temperatures have risen and fallen during 5 separate climate change cycles. So would it be correct to assume the CO2 levels have also risen and fallen naturally as well?
34. crucilandia
7:29 PM GMT on September 21, 2007
Michael

I just found this site about sea ice and warm air.

check this:

http://www.sciencedaily.com/releases/2005/06/050630064726.htm
Member Since: March 6, 2007 Posts: 0 Comments: 2212
33. crucilandia
7:28 PM GMT on September 21, 2007
it is true. if the antarctica is colder than the surrounding area the wind should flow northwards away from the vortex center.

There has been heavy precipitation in the continent and I don't know if plays a role in ice formation or extention of seaice. pushing outwards. other thing, since AAO is negative there is a lot of more wind over water that will cause polynias and increase ice formation.

The AAO has been in the negative from june to august. that explains the colder temperatures in the south america.

another thing is that in Antarctica there are inversion phenomena. where a warmer air of about 300m trapped by a cold upper air. so I don't know if the data is from a satellite or ground interpolation.
Member Since: March 6, 2007 Posts: 0 Comments: 2212
32. cyclonebuster
5:47 PM GMT on September 21, 2007
Link
Member Since: January 2, 2006 Posts: 128 Comments: 20482
31. cyclonebuster
5:46 PM GMT on September 21, 2007
"In a new NASA study, researchers using 20 years of data from space-based sensors have confirmed that Antarctic snow is melting farther inland from the coast over time, melting at higher altitudes than ever and increasingly melting on Antarctica's largest ice shelf."
Member Since: January 2, 2006 Posts: 128 Comments: 20482
29. cyclonebuster
4:21 PM GMT on September 21, 2007
Link
Member Since: January 2, 2006 Posts: 128 Comments: 20482
28. cyclonebuster
4:21 PM GMT on September 21, 2007
Snowmelt In Antarctica Creeping Inland, Based On 20 Year Of NASA Data
Science Daily On the world's coldest continent of Antarctica, the landscape is so vast and varied that only satellites can fully capture the extent of changes in the snow melting across its valleys, mountains, glaciers and ice shelves.
A map of Antarctica indicates first time persistent melting detected within the study period from 1987-2006. Areas where persistent melting took place are shown in darker shades of green.
Member Since: January 2, 2006 Posts: 128 Comments: 20482
27. crucilandia
2:29 PM GMT on September 21, 2007
this graph uses the mean temperature between 1985 to 1995 as base. Since antarctica temperatures vary extremely between winter and summer, the 12C anomaly for this time of the year is fine.

The annual average temperature is -50C (-58F).


Winter temperatures drop quickly, then level out. Summer is short, from mid-December to mid-January, however, temperatures can reach a balmy -30C (-22F)! This is partly due to the increase in solar radiation, but also the surface of the ice is a little darker and, therefore, less reflective after the winter
Member Since: March 6, 2007 Posts: 0 Comments: 2212
25. desertdisaster
12:45 PM GMT on September 19, 2007
Snowfire, Even if lower salinity of surface water around Antarctica is not the official explanation for now, Its a good suspect. Also the Cryosphere today site reports that they found a small glitch in their software The time series have now been corrected and are showing that we are very close to, but not yet, a new historic maximum sea ice area for the Southern Hemisphere.Link

And if you look closely at the Global sea ice area average since 1979 on this Graphic you will notice that we lost 1 000 000 square KM and that the trend is increasing
24. Snowfire
2:47 AM GMT on September 19, 2007
Although the increase in GHGs is indeed uniform, the expected pattern of warming is not. The earth is more complicated than that, being an interconnected system of shifting air and ocean currents, landmasses with changing albedo, etc. It is entirely possible that short-term regional cooling can occur as a result of such processes even though the earth as a whole is still warming. The Younger Dryas period is a historical example of this. Moreover, if surface salinity around Antarctica drops (as the result of increased glacial melting), the freezing point of the water itself will rise, and more of the ocean may freeze even if temperatures are still increasing.
Member Since: June 29, 2005 Posts: 24 Comments: 311
23. sullivanweather
10:19 PM GMT on September 18, 2007
Cruc,

They are both interconnected.

Without that strong circumpolar wind current in the atmosphere the circumpolar ocean currets wouldn't exist.

Besides, the fact that the Antarctic peninsula has warmed by some 2-4 degrees shows that warmer ocean currents are making it down it Antarctica.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
22. crucilandia
10:18 PM GMT on September 18, 2007
Sullivan is rigth

If the CO2 is a conservative feature in the ATM, it must heat the globe equally. Since CO2 IR traping is so small compared to other factors, the temperature in Antarctica does not respond to the CO2 concentration.
Member Since: March 6, 2007 Posts: 0 Comments: 2212
21. crucilandia
10:14 PM GMT on September 18, 2007
sullivan

The fact that Antarctica has a strong circumpolar vortex surrounding the continent

they were talking about the currents in the ocean around Antarctica.
Member Since: March 6, 2007 Posts: 0 Comments: 2212
20. sullivanweather
9:53 PM GMT on September 18, 2007
No...I'm saying that GHG concentrations are virtually the same both globally and in Antarctica.

Member Since: March 8, 2007 Posts: 273 Comments: 12612
19. cyclonebuster
9:49 PM GMT on September 18, 2007
It doesn't matter which colour the landmass is. There's still the same percentage of outgoing radiation now as there was in the 60's or before the industrial revoultion even, overall. If there's more CO2 in the atmosphere both globally and in Antarctica than there was during those times it is entirely plusable that there should be a uniform rise in temperature.


CO2 forcing doesn't cease just because the temperatures in the locations in question are 50 below or 30 above (celsius)



So are you saying the Ice holds as much heat as dark land does?
Member Since: January 2, 2006 Posts: 128 Comments: 20482
18. sullivanweather
9:45 PM GMT on September 18, 2007
It doesn't matter which colour the landmass is. There's still the same percentage of outgoing radiation now as there was in the 60's or before the industrial revoultion even, overall. If there's more CO2 in the atmosphere both globally and in Antarctica than there was during those times it is entirely plusable that there should be a uniform rise in temperature.


CO2 forcing doesn't cease just because the temperatures in the locations in question are 50 below or 30 above (celsius)
Member Since: March 8, 2007 Posts: 273 Comments: 12612
17. cyclonebuster
9:07 PM GMT on September 18, 2007
sullivanweather at 8:37 PM GMT on September 18, 2007.

Are we losing sight of the fact that Antarctica is a landmass?!

A white landmass not a dark one. Big difference!
Member Since: January 2, 2006 Posts: 128 Comments: 20482
16. DoverDan0
9:02 PM GMT on September 18, 2007
"A landmass that actually reflects most of the incoming solar radiation right back into the atmosphere from snow/ice albedo effects?"

Actually, the radiation would be mostly reflected back into space as the atmosphere (including CO2) is pretty transparent to visible radiation. The greenhouse effect would only come into play if the surface is warmed by absorbed sunlight (IR emission is temperature dependant). Maybe this could account for a lack of warming in Anarctica?
15. sullivanweather
8:37 PM GMT on September 18, 2007
Are we losing sight of the fact that Antarctica is a landmass?!

A landmass that actually reflects most of the incoming solar radiation right back into the atmosphere from snow/ice albedo effects?
Member Since: March 8, 2007 Posts: 273 Comments: 12612
14. cyclonebuster
8:08 PM GMT on September 18, 2007
In fact I would say the larger land mass radiates more of the suns energy back into the atmosphere in the Northern lattitudes and well into night time hours. Unlike the oceans do they absorb it.
Member Since: January 2, 2006 Posts: 128 Comments: 20482
13. cyclonebuster
8:04 PM GMT on September 18, 2007
desertdisaster,
You are correct.
Member Since: January 2, 2006 Posts: 128 Comments: 20482
12. desertdisaster
6:29 PM GMT on September 18, 2007
Have you been drinking Sullivan? Im sure you make your own! You should give me your recipe one day I have to go in a meeting for now
Take it easy
11. sullivanweather
6:18 PM GMT on September 18, 2007
It really can't get much more simple.

The concentration of GHG's (excluding water vapour) are within a few PPM/PPB of the global average no matter where one finds themselves on this planet.

The fact that Antarctica has a strong circumpolar vortex surrounding the continent, preventing much north-south flow of air, should provide an excellent 'controlled' environment for studing the effects of GHG's on temperature. Most of Antarctica has not warmed over the last 50 years. For the most part Antarctica has cooled some, other than the peninsula.

This should serve as a further example that warmer ocean currents are making it to Antarctica.
Member Since: March 8, 2007 Posts: 273 Comments: 12612
10. desertdisaster
5:54 PM GMT on September 18, 2007
Well, well my dear friend Sullivan again! Arent you busy picking up tomatoes! Or you just want to argue for the fun of it!
Seriously, I dont understand what you dont find logic in the above explanation. So I cant put myself in your head and understand it for you the explanation is very clear!
Maybe you could explain in details, point by point why you disagree with it
Go ahead, make my day!
9. sullivanweather
5:19 PM GMT on September 18, 2007
Posted By: desertdisaster at 7:58 PM GMT on September 17, 2007.

This is not from me but, I found this as an explanation for the Antartic ice:

This is not actually a surprise. In fact, it is completely in line with model expectations that CO2 dominated forcing will have a disproportionately large effect in the north. The reasons lie in the much larger amount of land in the northern hemisphere and the fact that the ocean's thermal inertia and ability to mix delay any temperature signal from the ongoing absorbtion of heat. The circumpolar current also acts as a buffer preventing warm water from the tropics from transporting heat to the south pole, a buffer that does not exist in the north...

Make sense to me...


--------------------------

This doesn't make any sense to me. The concentrations of GHG's are fairly uniform throughout the globe. The effect of GHG warming in Antarctica should be proportionate to the supossed GHG warming experienced over the other continents, regardless of the circumpolar vortex.

Member Since: March 8, 2007 Posts: 273 Comments: 12612
8. cyclonebuster
4:36 PM GMT on September 18, 2007
desertdisaster at 7:58 PM GMT on September 17, 2007.

This is not from me but, I found this as an explanation for the Antartic ice:

This is not actually a surprise. In fact, it is completely in line with model expectations that CO2 dominated forcing will have a disproportionately large effect in the north. The reasons lie in the much larger amount of land in the northern hemisphere and the fact that the ocean's thermal inertia and ability to mix delay any temperature signal from the ongoing absorbtion of heat. The circumpolar current also acts as a buffer preventing warm water from the tropics from transporting heat to the south pole, a buffer that does not exist in the north...

Make sense to me...

CORRECT!!
Member Since: January 2, 2006 Posts: 128 Comments: 20482
7. crucilandia
4:05 PM GMT on September 18, 2007
adsorption: the accumulation of molecules of a gas to form a thin film on the surface of a solid

CO2 is dissolved in seawater. goes into solution

- there are other factors besides temperature affecting the solubility pump

...resulting in more co2 being released in the tropics...

- Why do you think more co2 will be released from the tropics?
Member Since: March 6, 2007 Posts: 0 Comments: 2212
6. robodave
3:41 PM GMT on September 18, 2007
What is different now than in the past few cycles?

It looks like the CO2 is much, much elevated. Still, the temperature is far behind, unlike that chart. This causes me to doubt that co2 has as much of an impact on temperature as it is touted to have.

Plus what is the role of ice, especially sea ice.

The lack of sea ice would heat polar waters. That would decrease the absorption of co2 because it is warmer, while further increasing the global heat budget, resulting in more co2 being released in the tropics. So this would seem to suggest that as temperatures go up, less and less co2 will be absorbed, while more and more of it will be released into the atmosphere.

One question that has been on my mind lately is how much of the "global warming" (heat, not co2) is being absorbed/masked by the oceans? Sort like, if the sun were pouring energy on us, and the oceans are this giant capacitor. So we're floating on this big cauldron of energy. So you're saying co2 is absorbed by the oceans, but what about heat? I know as well as anyone else that, water heats up during summer, right? Well, where does it go?

StSimonsIslandGAGuy:

Strange how in the arctic, sea ice is at a record low since satellite surveillance began, and it is at a record high in the antarctic.

Thats right! Its hush hush. Not being fairly presented.

Desertdisaster:

The circumpolar current also acts as a buffer preventing warm water from the tropics from transporting heat to the south pole, a buffer that does not exist in the north...


Why does this buffer not exist in the north?

Snowfire:

When the primary forcing mechanism is something other than carbon dioxide, temperature variations will lead carbon dioxide variations (e.g. the ice age variations). If the primary forcing mechanism is the emissions themselves, then temperature excursions will trail emissions fluctuations. We have examples of both cases, and this should come as no surprise.


A 1x1, cause/effect relationship is not proven. Not enough evidence for scaremongering. Concern? Sure.
Member Since: August 9, 2007 Posts: 1 Comments: 147
5. Snowfire
3:26 PM GMT on September 18, 2007
When the primary forcing mechanism is something other than carbon dioxide, temperature variations will lead carbon dioxide variations (e.g. the ice age variations). If the primary forcing mechanism is the emissions themselves, then temperature excursions will trail emissions fluctuations. We have examples of both cases, and this should come as no surprise.
Member Since: June 29, 2005 Posts: 24 Comments: 311
4. desertdisaster
7:58 PM GMT on September 17, 2007
This is not from me but, I found this as an explanation for the Antartic ice:

This is not actually a surprise. In fact, it is completely in line with model expectations that CO2 dominated forcing will have a disproportionately large effect in the north. The reasons lie in the much larger amount of land in the northern hemisphere and the fact that the ocean's thermal inertia and ability to mix delay any temperature signal from the ongoing absorbtion of heat. The circumpolar current also acts as a buffer preventing warm water from the tropics from transporting heat to the south pole, a buffer that does not exist in the north...

Make sense to me...

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About RickyRood

I'm a professor at U Michigan and lead a course on climate change problem solving. These articles often come from and contribute to the course.

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