Sea Ice North: The new field of ice-free Arctic Ocean science

By: Dr. Ricky Rood , 10:43 PM GMT on April 28, 2011

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Sea Ice North: The new field of ice-free Arctic Ocean science

I recently read a paper in Physics Today entitled The Thinning of Arctic Sea Ice by R. Kwok and N. Untersteiner. (Nice essay by Untersteiner) This paper was written for a general scientist audience, and provides a good summary of the state of the science. The primary focus of the article is on understanding the small change to the surface energy balance required to explain the increased rate of sea ice melt in the summer. Some time ago I wrote a few blogs on Arctic sea ice; they can be found here and this one is most relevant: Sea Ice Arctic.

When the IPCC Assessment Report was published in 2007 the Arctic sea ice was in visible decline. In the summer of 2007 there was a record decline that caught the attention of both climate scientists and the broader public. As suggested in Kwok and Untersteiner immediately following the release of the 2007 IPCC report papers started to appear about how the IPCC synthesis had underestimated the melting of both sea ice and ice sheets. Much of this underestimate could be summed up as simplistic representation of the dynamics of ice melting. For example, brine-laden sea ice floating in salty sea water turns over. Snow gets on the top. It melts, then there are puddles and ponds that can flow down into ice. Simplistically, and I am a simpleton, it’s like a pile of ice cubes sitting in a glass versus stirring those ice cubes, or blowing air over the ice, heat gets carried around and ice melts faster.

The presence of large areas of open ocean in the Arctic is new to us. It motivates new research; it motivates claims to newly accessible oil, gas, and minerals; it motivates new shipping routes; it suggests changes in the relationships of nations; it motivates the development of a military presence. (All things Arctic from the Arctic Council) The natural progression of scientific investigation starts to explore, describe, and organize what is to us modern-day humans: a new environment, new ecosystems, and new physical systems. For example, the Mackenzie River now delivers a massive pool of fresh water into the ocean. Fresh and salt – big differences to flow in the ocean because the density is different; big difference to the formation of ice because the freezing temperature is different; and big differences in the plants and animals in the water.

Compared with trying to attribute the contribution of global warming to a particular weather event, it is easier to link the recent, rapid decrease of sea ice to a warming planet. The freezing, melting and accumulation of ice require persistent heating or cooling. It takes a lot of heat for a sustained period to melt continental-size masses of ice. Historically, the sea ice that was formed in the winter did not melt in the summer and there was a buildup of ice over many years – it accumulated; it stored cold. Around the edges of this multi-year ice are areas where the sea froze and melted each year. The melting of multi-year ice, therefore, represents the accumulation of enough heat to counter years of cold. The movement, poleward, of the area where ice freezes and thaws each year is the accumulation of spring coming earlier. The requirement for energy to persist and accumulate to affect changes in sea ice reduces the uncertainty that is inherent in the attribution of how much global warming has impacted a particular event.

Understanding the detailed mechanisms that provided the heat to melt the ice remains a challenge. (This is the real point of in Kwok and Untersteiner) We know it takes about 1 watt per square meter of energy to melt that much ice that fast. This could be delivered by the Sun, transported by the air, by the ocean, by warm water from the rivers of Canada and Siberia, by snow – yes, snow is energy. Once the ice is gone in the summer, then the ocean can absorb heat from the Sun. If there is growth of phytoplankton or zooplankton, then they might enhance the absorption of energy – yes, life is energy. Ocean acidification might change. The natural question that arises – do these processes that are active in this new environment work to accelerate sea ice melting or might they contribute to freezing of water. What are the local feedbacks? (This is above – see below.)

Another study that is of interest is the paper in Geophysical Research Letters, Recovery mechanisms of Arctic summer sea ice, by S. Tietsche and colleagues. This is a model study. With a model the scientist owns the world and can prescribe what it looks like. In these numerical experiments, the Arctic is prescribed with no ice. Then whether or not the ice recovers is explored. In these studies the ice does recover. The ocean does indeed take up extra heat in the summer, but it gives it up quickly in the fall. This is followed by the formation of first year ice in the winter. The ice-albedo feedback that might let the ice melt runaway is limited. Tietsche et al. conclude that it is not likely that Arctic sea ice will reach a tipping point this century.

This does not mean that summer ice loss will decrease. This does not mean that there will not be huge changes in the Arctic. This only says that it still gets cold in the winter.

Models: One of the things I like about the Kwok and Untersteiner paper is their brief discussion of models. They point out that none of the models available for the 2007 IPCC assessment were able to predict the rate of sea ice decrease. Looking forward, they state that the model projections for 2060 range from no sea ice in September to more sea ice than is observed today. The Tietsche et al. paper is a focused model experiment – not a climate projection. It is also a model result that, perhaps, helps to understand the differences in the 2060 projections. That is, how is the recovery of sea ice in the autumn represented in the projection models?

A couple of other points: First, the amount of energy needed to cause the observed melting in sea ice is 1 watt per square meter. If you calculate the amount of energy in the different factors at play in melting of sea ice, then the numbers are 10s of watts per square meter. As suggested above, there are many reservoirs of energy – the Sun, rivers, etc. So when we look at the different ways 1 watt per square meter can be delivered to the sea ice, then there are several paths. The existing models tell us that with the increased heat due to greenhouse gases, energy gets delivered to the Arctic and sea ice melts. The existing models say that there might be several different paths; it is likely, that several of them operate at different times. The second point: Of course the Tietsche et al. paper will enter as an isolated contribution to the political argument, Arctic “death spiral” – as will those of accelerated melt, New warning on ice melt.

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Figure 1: Simplistic summary of Arctic sea ice

Useful links
Recent sea ice trends
Sea ice data
Rood’s Blogs on Ice

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Quoting MichaelSTL:
Snowlover needs to explain why the Southern Hemisphere doesn't show any of the variation seen in the Northern hemisphere if the PDO and AMO are the cause and they affect the entire globe.


Perhaps maybe the NH has more land than the SH?



Thus it is more variable than the SH, since the land temperatures are more variable than the ocean temperatures.

The Global Average though shows that when the PDO was cool, the temperatures cooled, and vise versa.

Quoting MichaelSTL:
Also, I wonder if his handle has anything to do with why he denys that warming is occurring, since it means less snow (well, depending on where you live). But I like snow too but that doesn't make me deny that it is warming.


LOL I thought Global Warming meant more snow???

http://articles.cnn.com/2011-01-27/opinion/kaku.s nowstorms.global.warming_1_global-warming-monster- snowstorms-human-activity?_s=PM:OPINION

But we all love our conspiracy theories...

Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting MichaelSTL:
By the way, a negative feedback does not mean that a forcing would cause cooling! Negative feedbacks only REDUCE the warming that would otherwise occur.


Negative Feedbacks would reduce the warming, if they are not as great of a feedback. If the initial climatic response to co2 was 1 Degree F and the Feedback was -1.2 F, then co2 would cause -.2 Degree F of cooling, since the feedback is greater than the actual co2 increase itself.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
I'm I've got to go out for a while; I'll check back later this evening or tonight.

Edited: LOL...What the heck?
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting cyclonebuster:


How about both?


Sure! Could you present the evidence?
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Concerning but not replying to № 165; blockquotes are from MichaelSTL:

A positive PDO (shown on the left) is NOT all about warmer water everywhere! Sure, it may get warmer in North America since it is downstream of warmer water, but it sure doesn't get warmer elsewhere. In fact, I'd bet that Japan had their hottest summer on record last year because the PDO was negative, leading to warmer water by them.


Sure, but it seems pretty clear to me that looking at the two globes that the one on the right is going to have higher global SSTs than the one on the left. Am I only the only one that thinks this is obvious?

Funny also that the PDO has been "cooling" since the 1980s - yet it has continued to warm at virtually the same rate!


Seriously? The PDO was in a positive phase at least until the late 90s, and the long term phase is what seems to correlate to temperature trends. This is like saying that a La Niña begins right after the ENSO index peaks and begins decreasing.

Second: the 1940-1975 time period experienced anthropogenic global cooling. This cooling was from the same root cause as volcanic cooling, namely aerosols (mostly sulfate aerosols) in the atmosphere. Whereas volcanic eruptions are natural, and often inject aerosols into the stratosphere (the upper layer of earth’s atmosphere), aerosols from industrial activity are man-made and almost entirely in the troposphere (the lower layer of earth’s atmosphere, where most of our weather takes place).


Certainly possible, but I believe uncertain. I've never seen anything that convincingly places the cause of that cooler period on aerosols alone. Aerosols both cool and warm the atmosphere, depending on the type. There is still uncertainty on what the overall forcing due to aerosols is today, let alone forty years ago.

Did you know that the measured heat balance is positive, meaning that the Earth is warming, even in recent years?[...]


I'm not convinced that we can measure the "overall heat balance" with enough certainty. There are too many places where temperatures are too sparsely measured. Even outgoing longwave radiation is sparsely measured. We have an idea, but large uncertainties exist.
Member Since: February 19, 2010 Posts: 0 Comments: 580
№ 169

I have to admit, although I'm generally not concerned with what people say in response to my posts, it is refreshing to at least see someone make the effort to understand what I have to say despite the fact we probably disagree on a number of specifics.

I'm not entirely clear on what you meant in the last sentence, but I'm going to address with an assumption in mind. I can see where someone might conclude that the detrended PDO is simply a reflection of the global temperature trend. In a sense, we don't disagree on this. However, what is interesting to me is that the specific regional conditions that exist during a positive/negative PDO phase seem to correlate with periods of increases/decreases in global temperatures; the actual PDO index itself is just a number. I guess it is plausible that an increase in global temperatures could cause the changes we see during a positive PDO, but it seems more likely to me that the reverse happens. Maybe it's not even important which causes which, as it really just seems like an uneven warming trend.

The main point here, because of the way that we measure how much the earth has warmed, I believe a significant portion of the warming that we've seen could be due to cyclical redistribution of heat within the climate system, of which I don't think we have a complete enough understanding. I think the true warming signal would be better measured from time periods that attempt to neutralize this variation, say from 1945-1995 or something similar. Just working off the cuff here, and using GISS measurements as more desirable satellite measurements (in my opinion, of course) are not available that far back, I would say that would yield about 0.1°C warming per decade with PDO effects excluded; this warming would be due to other factors, of which CO₂ increases would certainly be a contributor.

An important consequence of this is that climate models assume far more warming than this, and consequently predict more warming than I think will verify. This is my opinion, of course.
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting MichaelSTL:


It is also interesting to see the trend for ENSO:



At first glance, this does not look like an ENSO time series. However, there is a large spike in the year 1998 which was the year of the super El Nino. Also indicative of an ENSO signal is the peak for the 1983 ENSO, and the current La Nina. But the main signature of this figure is the downward trend. Looking at the EOF figure above, we can interpret what this means. Since the early 1900s, the temperature in the tropical Pacific has been decreasing (the EOF is positive and the trend is negative), while the western Pacific has been warming (a negative EOF and a negative trend).



That is also evident when you look at heat content:





The trend is even evident in the Nino region SST data, especially in the Nino 4 region in the central Pacific (which in turn is causes changes in El Nino):


Yes that was interesting too, I almost mentioned that in my post, but I didn't want to steer away from the PDO.

Interesting nonetheless to see what this means for the future.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Quoting MichaelSTL:
The PDO was more negative during the MWP, much more so than during the 1970s, which according to deniers was warmer than today... Oh yes, and more positive during the LIA... so I'd say that the correlation is negative (i.e. a positive PDO causes cooling, or the PDO is affected by changes in temperature, the latter which seems more likely).


Yes, that is very interesting, although the error margins are probably even higher than the temperature proxy reconstructions to the year 1000.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting TomTaylor:

Please tell me how the PDO alters/changes/governs global temperatures.


Sure thing. First, the PDO governs the temperatures by warming up the landmasses in both the Southern and Northern Hemisphere, where the landmasses brush the PDO. The Warmer than normal SSTs then warm the continental landmasses by warming the air that comes in the form of an onshore flow.

Next, as shown in my graph, the PDO and ENSO intertwine at the Equatorial Pacific. And what is very much known, is that the warming and cooling of the Equatorial Pacific greatly warms and cools the globe, due to Earth's Global Heat Budget. A cooler PDO would favor more strong La Ninas, which in turn would cool the globe.

.
Here is a news article from NASA supporting this.


QUOTE

"This multi-year Pacific Decadal Oscillation 'cool' trend can intensify La Niña or diminish El Niño impacts around the Pacific basin," said Bill Patzert, an oceanographer and climatologist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The persistence of this large-scale pattern tells us there is much more than an isolated La Niña occurring in the Pacific Ocean."

"The comings and goings of El Niño, La Niña and the Pacific Decadal Oscillation are part of a longer, ongoing change in global climate," said Josh Willis, a JPL oceanographer and climate scientist. Sea level rise and global warming due to increases in greenhouse gases can be strongly affected by large natural climate phenomenon such as the Pacific Decadal Oscillation and the El Nino-Southern Oscillation. "In fact," said Willis, "these natural climate phenomena can sometimes hide global warming caused by human activities. Or they can have the opposite effect of accentuating it."



Quoting TomTaylor:

Surely you remember, correlation =/= causation


Correct. But remember that this could go both ways, such as co2 and temperature.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting Snowlover123:,
Quoting TomTaylor:

Additionally, the PDO & AMO are only known to have regional effects, limited to the N Hemisphere. Yet teh S Hemisphere is warming too.


False.



Credit goes to BethesdaWX for making this image.

Please tell me how the PDO alters/changes/governs global temperatures.

That is the one piece of the puzzle your theory fails to explain. I've already showed how PDO with trend reflects global temps with trend, so if anything PDO reflects global temps, however if you still insist it's the other way around, please explain the mechanism for this process.

Surely you remember, correlation =/= causation
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Snowlover, see SirmaelStrom's post, I was wrong

Quoting sirmaelstrom:


The PDO is detrended from the overall warming signal, so it shouldn't necessarily show any correlation at all. Overall a sufficiently long observation period, likely hundreds of years, it should average out to zero. The correlation of the PDO and global temperature change at least indicates that part of the warming we have seen could be simply cyclical redistribution of heat within the overall climate system. We simply are not able to measure everywhere with enough resolution to track all of these changes (e.g. measurements of the deep ocean are very sparse and large interpolations/assumptions are made).


With regards to the PDO, read this article

Link

If you don't want to read through the whole article, here's the main point:

"The "classical" definition of PDO excludes any trend in the data. But what would happen if the trend were not excluded?



At first glance this may not look at all like the traditional PDO (UW link above). However, there are qualities that support the notion that this is the PDO with a trend. I've included the slope of the first PC as the red dashed line as a visual reference. In the 1940s, the PDO is larger than the red line, during the 50s and 70s its below or near the line, and during the period from the 1980 to present it is mostly above the line. But usually, the PDO graph is not shown as a simple line like above, but blue and red colors are added to indicate when the PDO is in the "warm" or "cold" phase.


This graph would be equivalent to the PDO graph produced on the UW website. Except I've added the cyan line to indicate that the mean value has been changing. (The slope is about 0.5 standard deviation per century.) If we simply remove the slope, the far past will "warm", and the near past will "cool", and it will look almost exactly the same as the UW graph. When presented as above, the "phase shift" that occurred in 1977 is not notable compared to other "phase shifts" during the period of record."



Basically, as Sirmaelstrom said, the PDO index is created such that by the end of the period of time, there is no trend. What this guy does in this article, is he shows the data with the trend (first graph). With the trend, it shows warming.

What this all really means is that the PDO with the trend shows warming, just as global temperatures are.





So, raw PDO data trends(trend not removed), should roughly reflect global temperature trends (because they don't have the trend removed either). However, when the trend is removed, as in this case



it will not reflect global temperatures. Instead it will only reflect periods of warming and cooling. I believe this is what is misleading you to believe that the PDO is causing warming and/or cooling.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Concerning but not replying to № 160:

There is still much uncertainly concerning climate sensitivity and feedbacks. Below are two more links concerning feedbacks from Dr.Spencer.

Strong Negative Feedback from the Latest CERES Radiation Budget Measurements Over the Global Oceans

Our JGR Paper on Feedbacks is Published

Concerning but not replying to № 162:

It is true that an overall negative feedback does not imply cooling, but they imply that warming will stabilize. The predictions of most climate models assume that destabilization of the system will occur and warming will far exceed that due to simple forcings alone.

Concerning the Texas A&M study:
The observation period is likely too short to make useful inferences about climate sensitivity; the same goes for Dr.Spencer's paper as well. We simply do not know which any certainty what the overall climate sensitivity is at this time.



Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting Snowlover123:


They would both be acceptable. Do you have either one, by any chance?


How about both?
Member Since: January 2, 2006 Posts: 127 Comments: 20470
Well I have to get going now, so I will see you all in the evening.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting TomTaylor:
1. Co2 is not the only method in which we contribute to warming, there are many many more.


There are also many ways in which we can cool the climate, such as the way aerosoles impacted the formation of clouds, which have a significant cooling impact on the climate.

Quoting TomTaylor:

2. All that text about feedback loops are merrily your assumptions. Find me some peer reviewed evidence, and maybe I'll buy in to your assumptions.


Sure thing.

http://www.kirj.ee/public/Engineering/2007/issue_ 3/eng-2007-3-7.pdf

(Proceedings of the Estonian Academy of Sciences: Engineering, Volume 13, Number 3, pp. 260-268, September 2007)
- Olavi Kamer

http://www.leif.org/EOS/2009GL039628-pip.pdf

(Geophysical Research Letters, Volume 36, Issue 16, August 2009)
- Richard S. Lindzen, Yong-Sang Choi

http://www.kirj.ee/public/Engineering/2007/issue_ 3/eng-2007-3-7.pdfhttp://www.drroyspencer.com/Spen cer-and-Braswell-08.pdf

(Journal of Climate, Volume 21, Issue 21, November 2008)
- Roy W. Spencer, William D. Braswell

http://www.aai.ee/~olavi/cejpokfin.pdf

(Central European Journal of Physics, Volume 3, Number 2, June 2005)
- Olavi Kärner

http://www.aai.ee/~olavi/EE2007-ok.pdf

(Energy & Environment, Volume 18, Numbers 7-8, pp. 1059-1072, December 2007)
- Olavi Kärner

Quoting TomTaylor:

The PDO and AMO are climate indices. What is the PDO? A measure of SSTs in the Pacific. What is the AMO? A measure of SSTs in the Atlantic.


And when there are warm SSTs in the oceans, it is called a +PDO/AMO. The marine impact that the oceans can have is quite tremendous. Take New York City for Example. Severe Weather can usually never make it there at this time of year, since there is a more stable airmasses over NYC due to the marine onshore winds from the cool oceans that help cool NYC and make the atmosphere more stable there. The oceans have a huge impact on all continental landmasses.

Quoting TomTaylor:

Why do they appear to magically follow the temperature plot of global warming? Because they make up that graph. The PDO and AMO are one little chunk of that graph.

Understood? I hate when people think PDO -> GW. PDO reflects GW.


I think that "little" is underexaggerated, but that's my opinion. Note that on the GISS map, the warming really occurs when the PDO/AMO are both warm, which is what has happened since the satellite data.


Quoting TomTaylor:

Notice, they're not perfect mirror images of each other. This is because one is taking global temperatures, and the other is taking temperatures for one little sector of the globe.


Right, because the PDO and AMO are a measurement of that particular location. They have a different impact on different places.

Quoting TomTaylor:

Additionally, the PDO & AMO are only known to have regional effects, limited to the N Hemisphere. Yet teh S Hemisphere is warming too.


False.



Credit goes to BethesdaWX for making this image.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting Snowlover123:


Right. Either the feedbacks were enough to overthrow the warming effect of co2 or there was a natural cycle that was far more powerful than co2.



This is technically false. Assuming that there are NO climate feedbacks, the doubling of co2 has roughly the impact of a 1 Degree F temperature rise. However, in a climate filled with negative feedbacks, the effect of co2 might actually cool the climate. In a climate filled with positive feedbacks, the impact of co2 will be greatly magnified. We do not know much about the current climatic feedbacks in order to determine whether Man has participated in this current warming trend. The Climate Models all assume that co2 creates a positive feedback known as water vapour. They assume that the co2 heats the oceans, so that means that more water vapor must come from the oceans, right? Nope. Almost all of the water vapour is lost due to evaporation, and when the water droplets condense to form clouds, then this feedback has a net cooling impact. Feedbacks are what ultimately determine whether man has played a role in the climate. Natural cycles usually do not have feedbacks, so they are not as complicated to determine how much of an impact they have on the climate.



The Arctic is a very unique area. It is surrounded by continental landmasses. The PDO and the AMO surround the continental landmasses. When the oceans near the landmasses heat up, the landmasses heat up. Guess what happens to the Arctic since it is surrounded by warm continental landmasses? It warms up as well. The ocean currents from the PDO and AMO also help to warm the Arctic. In fact, most of the melting of the Arctic Sea Ice has occured from underneath. Which indicates that most likely, ocean currents, and the PDO/AMO are the reason for the melting of the Arctic Sea Ice since 1979.



I believe that since 1979, which is the most reliable data that we have, since satellites were launched then, that the PDO and AMO are solely causing that warming.

However, when one looks back a little bit further (and the error margins increase, since we are measuring the temperatures now with surface stations,) you will notice an identical warming trend when the PDO/AMO were warm. The Warming looks identical, and even according to the UN, co2 could not have played a role in the warming from 1900-1940. I suspect the same thing is going on right now.


Hmmm...Have to disagree here too. I do believe that the PDO is indicative of natural cyclical changes in the climate system that contribute to recent warming. However, it doesn't appear that they can be shown to be the only cause, as there is an underlying warming trend even when variations in the PDO are considered. Something has to be responsible for that, and CO₂ increases are certainly capable of causing some warming; thus it is reasonable to conclude that some of the warming is due to rising CO₂ levels.
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting TomTaylor:
1. Co2 is not the only method in which we contribute to warming, there are many many more.
2. All that text about feedback loops are merrily your assumptions. Find me some peer reviewed evidence, and maybe I'll buy in to your assumptions.



About the PDO and AMO, you couldn't be more wrong. The PDO and AMO are climate indices. What is the PDO? A measure of SSTs in the Pacific. What is the AMO? A measure of SSTs in the Atlantic.

Why do they appear to magically follow the temperature plot of global warming? Because they make up that graph. The PDO and AMO are one little chunk of that graph.

Understood? I hate when people think PDO -> GW. PDO reflects GW.

GW




PDO




AMO




Notice, they're not perfect mirror images of each other. This is because one is taking global temperatures, and the other is taking temperatures for one little sector of the globe.

Additionally, the PDO & AMO are only known to have regional effects, limited to the N Hemisphere. Yet the S Hemisphere is warming too.

So neither the PDO, nor the AMO explain GW.


The PDO is detrended from the overall warming signal, so it shouldn't necessarily show any correlation at all. Overall a sufficiently long observation period, likely hundreds of years, it should average out to zero. The correlation of the PDO and global temperature change at least indicates that part of the warming we have seen could be simply cyclical redistribution of heat within the overall climate system. We simply are not able to measure everywhere with enough resolution to track all of these changes (e.g. measurements of the deep ocean are very sparse and large interpolations/assumptions are made).
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting Snowlover123:
This is technically false. Assuming that there are NO climate feedbacks, the doubling of co2 has roughly the impact of a 1 Degree F temperature rise. However, in a climate filled with negative feedbacks, the effect of co2 might actually cool the climate. In a climate filled with positive feedbacks, the impact of co2 will be greatly magnified. We do not know much about the current climatic feedbacks in order to determine whether Man has participated in this current warming trend. The Climate Models all assume that co2 creates a positive feedback known as water vapour. They assume that the co2 heats the oceans, so that means that more water vapor must come from the oceans, right? Nope. Almost all of the water vapour is lost due to evaporation, and when the water droplets condense to form clouds, then this feedback has a net cooling impact. Feedbacks are what ultimately determine whether man has played a role in the climate.
1. Co2 is not the only method in which we contribute to warming, there are many many more.
2. All that text about feedback loops are merrily your assumptions. Find me some peer reviewed evidence, and maybe I'll buy in to your assumptions.



About the PDO and AMO, you couldn't be more wrong. The PDO and AMO are climate indices. What is the PDO? A measure of SSTs in the Pacific. What is the AMO? A measure of SSTs in the Atlantic.

Why do they appear to magically follow the temperature plot of global warming? Because they make up that graph. The PDO and AMO are one little chunk of that graph.

Understood? I hate when people think PDO -> GW. PDO reflects GW.

GW




PDO




AMO




Notice, they're not perfect mirror images of each other. This is because one is taking global temperatures, and the other is taking temperatures for one little sector of the globe.

Additionally, the PDO & AMO are only known to have regional effects, limited to the N Hemisphere. Yet the S Hemisphere is warming too.

So neither the PDO, nor the AMO explain GW.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Quoting sirmaelstrom:
%u2116 129


Site has been down for a while. I imagine that UAH sustained some damage from the tornado outbreak. I would think it will be back up in a week or so.


That would make sense. Incredible damage in Alambama where UAH is.

http://www.youtube.com/watch?v=OU6hsYk_sWI
Member Since: April 1, 2010 Posts: 9 Comments: 2699
№ 129
Quoting Snowlover123:
A bit off topic, but has anyone been able to get onto AMSU? It seems to be down for me.


Site has been down for a while. I imagine that UAH sustained some damage from the tornado outbreak. I would think it will be back up in a week or so.
Member Since: February 19, 2010 Posts: 0 Comments: 580
Quoting TomTaylor:
Yes, if you look at paleoclimate data you will find that not every warming period was cause by co2.


Right. Either the feedbacks were enough to overthrow the warming effect of co2 or there was a natural cycle that was far more powerful than co2.

Quoting TomTaylor::
So we are still responsible to some degree for our present warming trend.


This is technically false. Assuming that there are NO climate feedbacks, the doubling of co2 has roughly the impact of a 1 Degree F temperature rise. However, in a climate filled with negative feedbacks, the effect of co2 might actually cool the climate. In a climate filled with positive feedbacks, the impact of co2 will be greatly magnified. We do not know much about the current climatic feedbacks in order to determine whether Man has participated in this current warming trend. The Climate Models all assume that co2 creates a positive feedback known as water vapour. They assume that the co2 heats the oceans, so that means that more water vapor must come from the oceans, right? Nope. Almost all of the water vapour is lost due to evaporation, and when the water droplets condense to form clouds, then this feedback has a net cooling impact. Feedbacks are what ultimately determine whether man has played a role in the climate. Natural cycles usually do not have feedbacks, so they are not as complicated to determine how much of an impact they have on the climate.

Quoting TomTaylor:

And on the subject of feedback loops, you do understand that there are many positive feedback loops for warming right? That is one of the main reason scientists are so concerned with the arctic.


The Arctic is a very unique area. It is surrounded by continental landmasses. The PDO and the AMO surround the continental landmasses. When the oceans near the landmasses heat up, the landmasses heat up. Guess what happens to the Arctic since it is surrounded by warm continental landmasses? It warms up as well. The ocean currents from the PDO and AMO also help to warm the Arctic. In fact, most of the melting of the Arctic Sea Ice has occured from underneath. Which indicates that most likely, ocean currents, and the PDO/AMO are the reason for the melting of the Arctic Sea Ice since 1979.

Quoting TomTaylor:
I also have a question for you, if co2 is not the main cause of our current warming, then what is?


I believe that since 1979, which is the most reliable data that we have, since satellites were launched then, that the PDO and AMO are solely causing that warming.

However, when one looks back a little bit further (and the error margins increase, since we are measuring the temperatures now with surface stations,) you will notice an identical warming trend when the PDO/AMO were warm. The Warming looks identical, and even according to the UN, co2 could not have played a role in the warming from 1900-1940. I suspect the same thing is going on right now.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting cyclonebuster:

It depends on what one considers credible scientific evidence?

Would a video of a scale model of one working be good enough or how about a wonderware computer graphic image of one?


They would both be acceptable. Do you have either one, by any chance?
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting Snowlover123:
co2 warming did not drive the past climate, it will not drive this current climate. Take a look at the paleoclimatological data.



Note that while co2 was 10 times as much as it is now, the Earth was in an Ice Age.
Yes, if you look at paleoclimate data you will find that not every warming period was cause by co2.

However, that does not take away from he fact that co2 concentrations do have an effect on temperature. So we are still responsible to some degree for our present warming trend.

And on the subject of feedback loops, you do understand that there are many positive feedback loops for warming right? That is one of the main reason scientists are so concerned with the arctic.

I also have a question for you, if co2 is not the main cause of our current warming, then what is?
Member Since: August 24, 2010 Posts: 19 Comments: 4358
“Our prime purpose in this life is to help others. And if you can't help them, at least don't hurt them.”

Dali Lama
Member Since: Posts: Comments:
Quoting cat5hurricane:

Cyclone--I always liked the idea, and many, MANY others have to. Just keep to it, don't let the others deter your ambitions and endeavors. Like I said, we'll make this happen someday.

Kudos big guy. Done any fishing lately. Down in the Carolina cypress swamps the other day and then decided to hit the Black River near Andrews, SC to throw a line or two. Had a few beers, talked old times. Didn't get a whole lot of anything above legal limits, but catch and release is alright by me.

I just tell you that one you caught on your blog picture you showed me was incredible!


Quoting cat5hurricane:

Cyclone--I always liked the idea, and many, MANY others have to. Just keep to it, don't let the others deter your ambitions and endeavors. Like I said, we'll make this happen someday.

Kudos big guy. Done any fishing lately. Down in the Carolina cypress swamps the other day and then decided to hit the Black River near Andrews, SC to throw a line or two. Had a few beers, talked old times. Didn't get a whole lot of anything above legal limits, but catch and release is alright by me.

I just tell you that one you caught on your blog picture you showed me was incredible!


Were you getting reds or bass? I may make that big bass my avatar. Our trip to Tybee Island was canceled Wednesday due to small craft advisories. We came back home early only to dodge tornadoes. OUCH!A very bad week.
Member Since: January 2, 2006 Posts: 127 Comments: 20470
Quoting cat5hurricane:

Would Wattsupwiththat or Climateprogress count?

LOL. j/k.

Hey man, you know how much myself and WeatherWx are onboard with your Tunnel project. As soon as I meet with the rest of the suits and the articles or incorporation papers are drawn up, we'll sit down, have a cup of coffee (decaf for you of course, I remember), hopefully recruit a few others, and discuss architectural and engineering plans for this.

Good day, CB.


So I take it you like the idea? I am sure they can restore our climate back to pre-industrial revolution temperatures if needed.
Member Since: January 2, 2006 Posts: 127 Comments: 20470
Quoting Neapolitan:
Climate Change signal #7,051

King Crabs Invade Antarctica

It's like a scene out of a sci-fi movie -- thousands, possibly millions, of king crabs are marching through icy, deep-sea waters and up the Antarctic slope.

"They are coming from the deep, somewhere between 6,000 to 9,000 feet down," said James McClintock, Ph.D., University of Alabama at Birmingham Endowed Professor of Polar and Marine Biology.

Shell-crushing crabs haven't been in Antarctica, Earth's southernmost continent, for hundreds or thousands, if not millions, of years, McClintock said. "They have trouble regulating magnesium ions in their body fluids and get kind of drunk at low temperatures."

But something has changed, and these crustaceans are poised to move by the droves up the slope and onto the shelf that surrounds Antarctica. McClintock and other marine researchers interested in the continent are sounding alarms because the vulnerable ecosystem could be wiped out, he said.

Antarctic clams, snails and brittle stars, because of adaptation to their environment, have soft shells and have never had to fight shell-crushing predators. "You can take an Antarctic clam and crush it with your hands," McClintock said. They could be the main prey for these crabs, he said.

The king crabs' large numbers on the slope suggest that they are increasing in number at a rate faster than anticipated, McClintock said. "Before long, they could be in shallow water and on the shelf," he said. "This is a very visual, visceral way of thinking of an impact of climate change.

McClintock and his fellow researchers are exploring causes for the invasion, which they believe is linked to human-induced climate warming. "This is just one example of a species expanding its range into a new territory. There will certainly be more as the climate warms up," McClintock said.

Science Daily Article...



Is this 7,052? I am with ya Neapolitan.

Record Number of Whales, Krill Found in Antarctic Bays
ScienceDaily (Apr. 28, 2011) %u2014 Scientists have observed a "super-aggregation" of more than 300 humpback whales gorging on the largest swarm of Antarctic krill seen in more than 20 years in bays along the Western Antarctic Peninsula.

The sightings, made in waters still largely ice-free deep into austral autumn, suggest the previously little-studied bays are important late-season foraging grounds for the endangered whales. But they also highlight how rapid climate change is affecting the region.

The Duke University-led team tracked the super-aggregation of krill and whales during a six-week expedition to Wilhelmina Bay and surrounding waters in May 2009. They published their findings on April 27 in the online science journal PLoS ONE.

"Such an incredibly dense aggregation of whales and krill has never been seen before in this area at this time of year," says Duke marine biologist Douglas Nowacek. Most studies have focused on whale foraging habitats located in waters farther offshore in austral summer.

Nowacek and his colleagues observed 306 humpback whales -- or about 5.1 whales per square kilometer, the highest density ever recorded -- in Wilhelmina Bay. They measured the krill biomass at about 2 million tons. Small, floating fragments of brash ice covered less than 10 percent of the bay. The team returned in May 2010 and recorded similar numbers. Smaller but still higher-than-normal counts were also reported in neighboring Andvord Bay.




"Advancing winter sea ice used to cover much of the peninsula's bays and fjords by May, protecting krill and forcing humpback whales to migrate elsewhere to find food, Nowacek says. But rapid climate change in the area over the last 50 years has significantly reduced the extent, and delayed the annual arrival, of the ice cover, says Nowacek, who is the Repass-Rodgers University Associate Professor of Conservation Technology.

"The lack of sea ice is good news for the whales in the short term, providing them with all-you-can-eat feasts as the krill migrate vertically toward the bay's surface each night. But it is bad news in the long term for both species, and for everything else in the Southern Ocean that depends on krill," says Ari S. Friedlaender, co-principal investigator on the project and a research scientist at Duke."


Link
Member Since: January 2, 2006 Posts: 127 Comments: 20470

Quoting Snowlover123:


Can you back up how they work with credible scientific evidence?



Bump

It depends on what one considers credible scientific evidence?

Would a video of a scale model of one working be good enough or how about a wonderware computer graphic image of one?
Member Since: January 2, 2006 Posts: 127 Comments: 20470
Climate Change signal #7,051

King Crabs Invade Antarctica

It's like a scene out of a sci-fi movie -- thousands, possibly millions, of king crabs are marching through icy, deep-sea waters and up the Antarctic slope.

"They are coming from the deep, somewhere between 6,000 to 9,000 feet down," said James McClintock, Ph.D., University of Alabama at Birmingham Endowed Professor of Polar and Marine Biology.

Shell-crushing crabs haven't been in Antarctica, Earth's southernmost continent, for hundreds or thousands, if not millions, of years, McClintock said. "They have trouble regulating magnesium ions in their body fluids and get kind of drunk at low temperatures."

But something has changed, and these crustaceans are poised to move by the droves up the slope and onto the shelf that surrounds Antarctica. McClintock and other marine researchers interested in the continent are sounding alarms because the vulnerable ecosystem could be wiped out, he said.

Antarctic clams, snails and brittle stars, because of adaptation to their environment, have soft shells and have never had to fight shell-crushing predators. "You can take an Antarctic clam and crush it with your hands," McClintock said. They could be the main prey for these crabs, he said.

The king crabs' large numbers on the slope suggest that they are increasing in number at a rate faster than anticipated, McClintock said. "Before long, they could be in shallow water and on the shelf," he said. "This is a very visual, visceral way of thinking of an impact of climate change.

McClintock and his fellow researchers are exploring causes for the invasion, which they believe is linked to human-induced climate warming. "This is just one example of a species expanding its range into a new territory. There will certainly be more as the climate warms up," McClintock said.

Science Daily Article...
Member Since: November 8, 2009 Posts: 4 Comments: 13802
Quoting Snowlover123:


Can you back up how they work with credible scientific evidence?


Bump
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting Neapolitan:

Wrong on all counts. .

Here, have a look: http://www.niemanwatchdog.org/index.cfm?fuseactio n=background.view&backgroundid=00525


And the response to Joe Romm is here:

http://climateshiftproject.org/2011/04/18/respons e-to-statements-by-joe-romm-and-media-matters-for- america/
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting cat5hurricane:

You know, for someone who always preaches the importance of providing sound proof to back up there statement, I'm rather surprised I see such a blanket, straw man argument that completely dismisses and disputes all the variables against a differing opinion--all the while without offering or contributing equal, valid evidence to counter. If that's your new approach, why not just save some time with the fancy nonsense banter and instead just reply, "Your wrong. It's my way, and there's NO disputing that. EVER."

While it's always the "denialists" - as they call them - that are wrongly accused of the "straw man" argument and the grand old "shut down" statements, one cannot help but be absolutely baffled to see this occurring among the pro-AWG masses.

Interesting. I sure hope the well isn't running a bit dry, so to speak. Somehow I'm beginning to get that impression.

You'd best brush up on your logical fallacies, friend. If someone points at a published report to support a personal belief of theirs, it's not at all a "straw man" for someone else to point at a rebuttal report that refutes just about everything that first reports says--especially when the rebuttal report empirically backs up that refutation with numerous provable facts and figures.

Member Since: November 8, 2009 Posts: 4 Comments: 13802
Quoting InconceivableF6:
actually this is a highly, prestigious piece that is really a thorn is the sides of the climate scientists. I know i hate it, but it is actually very very valid.

i hate to say it, but the only person of whom is claiming it's debunked is you. i mean not to be mean as i'm on your side and believe earth is warming rapidly, but i sense you are a bit too sensational in your replies...

Wrong on all counts. The report is debunked nonsense. It's lies. It's garbage. It has absolutely no basis in fact. And it's only a "thorn" because it's annoying to us that denialists can only respond to science with personal attacks, untruths, and political blather.

Here, have a look: http://www.niemanwatchdog.org/index.cfm?fuseactio n=background.view&backgroundid=00525
Member Since: November 8, 2009 Posts: 4 Comments: 13802

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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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