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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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1 hour ago, Save the itchy algae! said:

What you said had no bearing on my comments at all.  Of course the ice is lowest now, its the latest in a long warming period, that's what you would expect.  It's irrelevant to the point I made.

So I guess we're in agreement that climate change is happening and that the sea ice is reflecting a period of ever increasing warming. Right?

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1 hour ago, WidreMann said:

So I guess we're in agreement that climate change is happening and that the sea ice is reflecting a period of ever increasing warming. Right?

Think that you'd get 97% agreement on that score.

Afaik, there is very broad agreement that global temperatures are up about 1 degree K since the 1880s. However, that warming has been in fits and starts, warm in the 1920s, colder in the early 1970s.

Obviously, the issue is to untangle the natural from the human impact, no easy task.  Given emissions, major changes in land use and population growth, even the details of the human impact are hard to decipher. 

That agreed, I do think that Snowlover91 has a good point, it is disconcerting to have above average ice growth in face of higher than normal air and ocean temperatures. Clearly there is something we do not understand about the process. It may be important or it may be trivial, but it should be investigated.

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3 hours ago, WidreMann said:

So I guess we're in agreement that climate change is happening and that the sea ice is reflecting a period of ever increasing warming. Right?

If that's what you got from the comment then you have more pressing concerns than climate change.  But to bring it down to  level, yes the climate is always changing.  And yes, the earth has been generally warming for 10-12,000 years so one would expect ice core samples to reflect that trend.  Per the other guy's point, the sea ice is not currently adequately reflecting a period of warming and thus (per the other other guy's point) there is more to the process than what our current understanding is.  A lot of what has been posted recently here in the form of articles is mainly an example of politicking and hubris.  

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Assuming extent gains increase by the 1981-2010 rate November will end with a mean of about 9.9e6 km^2. Then if we assume extents jump up and exactly match the 1981-2010 average (unlikely IMHO) then December will end with a mean of 12.8e6 km^2. This puts the final tally for 2018 at at mean 10.41e6 km^2. It would still be the 5th lowest annual mean just barely behind 2012 at 10.406e6 and 2017 at 10.393e6. Note that the top 5 would all be 2012 and later. So although the fast refreeze is interesting in it's own right it needs to be considered in context here. Unless someone has a convincing argument it's premature to think this is the start of a new era where sea ice extents begin a long term secular increase especially considering that we have a mountain of evidence that suggests sea ice extents will stagnate at best through the 2030's or just continue to decline.

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11 hours ago, bdgwx said:

Assuming extent gains increase by the 1981-2010 rate November will end with a mean of about 9.9e6 km^2. Then if we assume extents jump up and exactly match the 1981-2010 average (unlikely IMHO) then December will end with a mean of 12.8e6 km^2. This puts the final tally for 2018 at at mean 10.41e6 km^2. It would still be the 5th lowest annual mean just barely behind 2012 at 10.406e6 and 2017 at 10.393e6. Note that the top 5 would all be 2012 and later. So although the fast refreeze is interesting in it's own right it needs to be considered in context here. Unless someone has a convincing argument it's premature to think this is the start of a new era where sea ice extents begin a long term secular increase especially considering that we have a mountain of evidence that suggests sea ice extents will stagnate at best through the 2030's or just continue to decline.

I think something worth looking into is why the ice extent has been growing so rapidly when SST's in the region were 5-7C above normal in places? Obviously we are at the time of year when you'd expect some pretty fast gains but we moved from about 3rd in lowest ice extent to 13th in a matter of a few weeks with SST's that were as warm or warmer than previous years and anomalies that were above normal for the region. One would expect with SST's so far above normal that it would delay the freezing some and also the extent would be much lower than it is right now. Just looking at the latest NSIDC map, the only two regions that are noticeably absent of ice are the Chukchi Sea and Barents Sea areas while everywhere else is pretty close to the 1981-2010 mean and Hudson Bay is freezing a touch quicker than usual.

image.thumb.png.c67288142696488e35bd46d19064f7b9.png

 

If indeed the solar cycle and other factors like the AMO phase play a role as some research suggests then it's possible we could be seeing some signs of that with the solar min we are entering and the AMO possibly transitioning from a warm to a cold phase. Here's one study written on the AMO citing possible links between it and Arctic/Antarctic ice extent. IF indeed we are transitioning to a cold phase of the AMO then it will be interesting to see if we see an upward trend in Arctic ice levels the next 5-10 years or if things remain stable/decrease.

"Sea ice is an important component of the global climate system and a key indicator of climate change. A decreasing trend in Arctic sea-ice concentration is evident in recent years, whereas Antarctic sea-ice concentration exhibits a generally increasing trend. Various studies have investigated the underlying causes of the observed trends for each region, but possible linkages between the regional trends have not been studied. Here, we hypothesize that the opposite trends in Arctic and Antarctic sea-ice concentration may be linked, at least partially, through interdecadal variability of the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). Although evaluation of this hypothesis is constrained by the limitations of the sea-ice cover record, preliminary statistical analyses of one short-term and two long-term time series of observed and reanalysis sea-ice concentrations data suggest the possibility of the hypothesized linkages. For all three data sets, the leading mode of variability of global sea-ice concentration is positively correlated with the AMO and negatively correlated with the PDO. Two wave trains related to the PDO and the AMO appear to produce anomalous surface-air temperature and low-level wind fields in the two polar regions that contribute to the opposite changes in sea-ice concentration." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381096/

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43 minutes ago, snowlover91 said:

I think something worth looking into is why the ice extent has been growing so rapidly when SST's in the region were 5-7C above normal in places? Obviously we are at the time of year when you'd expect some pretty fast gains but we moved from about 3rd in lowest ice extent to 13th in a matter of a few weeks with SST's that were as warm or warmer than previous years and anomalies that were above normal for the region. One would expect with SST's so far above normal that it would delay the freezing some and also the extent would be much lower than it is right now. Just looking at the latest NSIDC map, the only two regions that are noticeably absent of ice are the Chukchi Sea and Barents Sea areas while everywhere else is pretty close to the 1981-2010 mean and Hudson Bay is freezing a touch quicker than usual.

Yeah. I agree. We try should to figure why this year's refreeze is more aggressive than in recent years. We should strive to figure out every little nuance of weather/climate no matter how detailed and trivial.

43 minutes ago, snowlover91 said:

If indeed the solar cycle and other factors like the AMO phase play a role as some research suggests then it's possible we could be seeing some signs of that with the solar min we are entering and the AMO possibly transitioning from a warm to a cold phase. Here's one study written on the AMO citing possible links between it and Arctic/Antarctic ice extent. IF indeed we are transitioning to a cold phase of the AMO then it will be interesting to see if we see an upward trend in Arctic ice levels the next 5-10 years or if things remain stable/decrease.

I'm sure solar cycles play a role. I just don't know how much. As with most things related to the climate its rarely ever just one thing. It's usually the net effect of a lot of stuff that makes for the best discriminator of climate behavior. For example, although a solar min by itself might not have much of an impact if it is phased precisely with a particular ENSO, AMO, and/or PDO cycle then the effect is magnified. My naive assumption is that solar cycles should have a bigger impact in the summer than the winter due to the fact that the poles receive relatively little solar insolation in the winter to begin with. But, I've learned over the years that my naive assumptions can be dead wrong. In fact, it's not unreasonable to think the link between sea ice extents and solar cycles is more indirect owing to the fact that the upper atmosphere is far more sensitive to the cycles than the troposphere. And of course, there are likely inertial lags between the peaks of the solar cycles and the peaks of the responses in the various elements of the climate system. I wouldn't be surprised if solar cycles have the complete opposite effect of what you'd expect as well.

Anyway, I did a quick google search and I found this very recent paper right away and it's not even behind a paywall...yay! I must confess...I haven't actually read it yet. I'll try to do that later today.

https://www.nature.com/articles/s41598-018-22854-0

This study investigates the role of the eleven-year solar cycle on the Arctic climate during 1979–2016. It reveals that during those years, when the winter solar sunspot number (SSN) falls below 1.35 standard deviations (or mean value), the Arctic warming extends from the lower troposphere to high up in the upper stratosphere and vice versa when SSN is above. The warming in the atmospheric column reflects an easterly zonal wind anomaly consistent with warm air and positive geopotential height anomalies for years with minimum SSN and vice versa for the maximum. Despite the inherent limitations of statistical techniques, three different methods – Compositing, Multiple Linear Regression and Correlation – all point to a similar modulating influence of the sun on winter Arctic climate via the pathway of Arctic Oscillation. Presenting schematics, it discusses the mechanisms of how solar cycle variability influences the Arctic climate involving the stratospheric route. Compositing also detects an opposite solar signature on Eurasian snow-cover, which is a cooling during Minimum years, while warming in maximum. It is hypothesized that the reduction of ice in the Arctic and a growth in Eurasia, in recent winters, may in part, be a result of the current weaker solar cycle.

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There's  nothing particularly rapid about the sea ice growth in the Arctic this month. But the record cold to the south of the Arctic in Hudson Bay area is responsible for the fast increase above average there. It looks like it could be a result of the Warm Arctic, Cold Continents pattern.

7th consecutive day of record #cold in Southern #Nunavut, this time extended into Northern Ontario, Quebec and Labrador as Arctic front moves south!#MeteoQC #ONwx #MBwx pic.twitter.com/PB7jyVrBak

IMG_0344.GIF.60f1e7c907c9ac45fbae3bad8744e778.GIF

IMG_0345.thumb.PNG.866df3d59c5bdb386d4e59879def568c.PNG

 

 

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27 minutes ago, bluewave said:

There's  nothing particularly rapid about the sea ice growth in the Arctic this month. But the record cold to the south of the Arctic in Hudson Bay area is responsible for the fast increase above average there. It looks like it could be a result of the Warm Arctic, Cold Continents pattern.

IMG_0344.GIF.60f1e7c907c9ac45fbae3bad8744e778.GIF

IMG_0345.thumb.PNG.866df3d59c5bdb386d4e59879def568c.PNG

 

 

Thank you, bluewave, for this very useful presentation of the ice data.  This kind of presentation helps clarify where things stand much better.  

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8 minutes ago, etudiant said:

Thank you, bluewave, for this very useful presentation of the ice data.  This kind of presentation helps clarify where things stand much better.  

No problem. Zack Labe does a great job putting together all the Arctic data in detail on his site. Patwx is a great resource on twitter for Canadian weather records. 

https://sites.uci.edu/zlabe/

https://mobile.twitter.com/pat_wx?lang=en

 

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23 hours ago, bluewave said:

There's nothing particularly rapid about the sea ice growth in the Arctic this month. But the record cold to the south of the Arctic in Hudson Bay area is responsible for the fast increase above average there. It looks like it could be a result of the Warm Arctic, Cold Continents pattern.

7th consecutive day of record #cold in Southern #Nunavut, this time extended into Northern Ontario, Quebec and Labrador as Arctic front moves south!#MeteoQC #ONwx #MBwx pic.twitter.com/PB7jyVrBak

 

 

 

I’d have to disagree with the bold part. While things have slowed down in recent days, the growth for about 3-4 weeks was quite high and we went from 3rd lowest to 13th lowest extent in the Arctic. Here’s some charts that showed how quickly we passed other years and the spikes in rapid gains. This link here has people who catalog things on a daily basis, we are now in the 9th lowest range. https://forum.arctic-sea-ice.net/index.php/topic,2223.2200.html

CB6A2ABA-CC68-4871-A064-9F60F664DEE5.png.7588ef8eda8ad731d10922a9868009f3.png

8B80F2FD-D427-41F9-97E7-AFFCD31015C6.png.af29389b75c8364aeae47dee59dfe923.png

 

The early gains were likely due to Hudson Bay freezing over faster than normal. It has since leveled off hence the slowdown in gains. The key this winter will be what happens in the Barents and Chukchi Sea since blocking and winter storms can erode ice in these areas. 

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39 minutes ago, snowlover91 said:

I’d have to disagree with the bold part. While things have slowed down in recent days, the growth for about 3-4 weeks was quite high and we went from 3rd lowest to 13th lowest extent in the Arctic. Here’s some charts that showed how quickly we passed other years and the spikes in rapid gains. This link here has people who catalog things on a daily basis, we are now in the 9th lowest range. https://forum.arctic-sea-ice.net/index.php/topic,2223.2200.html

The early gains were likely due to Hudson Bay freezing over faster than normal. It has since leveled off hence the slowdown in gains. The key this winter will be what happens in the Barents and Chukchi Sea since blocking and winter storms can erode ice in these areas. 

It was quite high in the Hudson Bay, but not the Arctic. That's why the regional sea ice figures tell the bigger story. 

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4 hours ago, bluewave said:

It was quite high in the Hudson Bay, but not the Arctic. That's why the regional sea ice figures tell the bigger story. 

Right, the Hudson Bay was well above normal and has now stalled in freezing over. However, the Arctic as a whole was making good progress compared with recent years. It was the 2nd highest level since 2005 but has now leveled off some. With the cold returning to the Hudson and also the Okhtosk area I expect gains will accelerate again in a few days. It certainly should be interesting to follow as well as the volume which IMO is even more important for summer melt and how well it holds up. 

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8 hours ago, snowlover91 said:

Right, the Hudson Bay was well above normal and has now stalled in freezing over. However, the Arctic as a whole was making good progress compared with recent years. It was the 2nd highest level since 2005 but has now leveled off some. With the cold returning to the Hudson and also the Okhtosk area I expect gains will accelerate again in a few days. It certainly should be interesting to follow as well as the volume which IMO is even more important for summer melt and how well it holds up. 

Quick gains in Hudson Bay won't do anything for the long term volume downward trend. It's a peripheral region outside the main Arctic basin that completely melts out in the summer. So you can't retain any ice there since it's all first year.

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3 hours ago, bluewave said:

Quick gains in Hudson Bay won't do anything for the long term volume downward trend. It's a peripheral region outside the main Arctic basin that completely melts out in the summer. So you can't retain any ice there since it's all first year.

If we are going to see a reversal in the ice extent and volume it will be a long term change that will take place over a few decades just like the downward trend has. The key is for things to stabilize and then see the volume starting to consistently increase on a 5-15 year scale. With solar min and a possible start to a cold phase of the AMO, the next 10+ years will be interesting to see what happens.

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1 hour ago, snowlover91 said:

If we are going to see a reversal in the ice extent and volume it will be a long term change that will take place over a few decades just like the downward trend has. The key is for things to stabilize and then see the volume starting to consistently increase on a 5-15 year scale. With solar min and a possible start to a cold phase of the AMO, the next 10+ years will be interesting to see what happens.

A solar minimum is no match for the CO2 forcing. There was a good paper out on this several years ago. As for the AMO, the sea ice was in decline during the last cold phase during the 80's into the mid-90's. Natural oscillations like the PDO and AMO can impact shorter term  rates of decline.  But the long term decline is a result of rising global and Arctic temperatures.

https://www.pik-potsdam.de/members/feulner/research/how-would-a-new-grand-minimum-of-solar-activity-affect-the-future-climate

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55 minutes ago, bluewave said:

A solar minimum is no match for the CO2 forcing. There was a good paper out on this several years ago. As for the AMO, the sea ice was in decline during the last cold phase during the 80's into the mid-90's. Natural oscillations like the PDO and AMO can impact shorter term  rates of decline.  But the long term decline is a result of rising global and Arctic temperatures.

https://www.pik-potsdam.de/members/feulner/research/how-would-a-new-grand-minimum-of-solar-activity-affect-the-future-climate

there it is the clear claim that the tiny amount of co2 in our air is more powerful than the SUN.........your side of this cant be believed on any level.

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And it's not just Rahmstorf that came to the conslusion that grand minimums will have minimal effect. You also have Meehl 2013, Anet 2013, and Jones 2012. Yes a hypothetical grand minimum will suppress the warming, but it won't stop it and it will only be temporary. Once the Sun comes out of its quiescent state that mitigation effect completely disappears. 

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26 minutes ago, BillT said:

there it is the clear claim that the tiny amount of co2 in our air is more powerful than the SUN.........your side of this cant be believed on any level.

That is not what bluewave or anyone has claimed. The claim is that Sun (like any main sequence star) is relatively stable in regards to it's luminosity. The variability in the radiative forcing is relatively small despite the magnitude of the radiative forcing being large. The change in radiative forcing of CO2 dominates over the change in radiative forcing of the Sun. Again, it's the change in the effects that are crucial in understanding the change in radiative forcing and thus the change in the heat uptake by the geosphere. Note that I have underlined change to drive home the point that it is the change in the system that puts pressure on the climate and ultimately the Arctic sea ice extents to also change.

For example, if the Sun were to experience a change of 0.25% in it's integrated luminosity then this is equivalent to 1360 W/m2 * 0.0025 / 4 = 0.85 W/m2 of forcing. But, a doubling of CO2 results in 5.35 * ln(560/280) = 3.7 W/m2 of forcing. That's more than 4x the effect. Plus, solar grand minimums are relatively short term compared to the long term impacts of CO2 which take 100s or even 1000s of years to die off to preindustrial levels. Note that a -0.25% change in TSI is considered to be on the high end of the forcing change for a hypothetical grand minimum.

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29 minutes ago, bdgwx said:

That is not what bluewave or anyone has claimed. The claim is that Sun (like any main sequence star) is relatively stable in regards to it's luminosity. The variability in the radiative forcing is relatively small despite the magnitude of the radiative forcing being large. The change in radiative forcing of CO2 dominates over the change in radiative forcing of the Sun. Again, it's the change in the effects that are crucial in understanding the change in radiative forcing and thus the change in the heat uptake by the geosphere. Note that I have underlined change to drive home the point that it is the change in the system that puts pressure on the climate and ultimately the Arctic sea ice extents to also change.

For example, if the Sun were to experience a change of 0.25% in it's integrated luminosity then this is equivalent to 1360 W/m2 * 0.0025 / 4 = 0.85 W/m2 of forcing. But, a doubling of CO2 results in 5.35 * ln(560/280) = 3.7 W/m2 of forcing. That's more than 4x the effect. Plus, solar grand minimums are relatively short term compared to the long term impacts of CO2 which take 100s or even 1000s of years to die off to preindustrial levels. Note that a -0.25% change in TSI is considered to be on the high end of the forcing change for a hypothetical grand minimum.

"A solar minimum is no match for the CO2 forcing"......that is the claim made that clearly is saying co2 is more powerful than the SUN.......

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2 hours ago, bluewave said:

A solar minimum is no match for the CO2 forcing. There was a good paper out on this several years ago. As for the AMO, the sea ice was in decline during the last cold phase during the 80's into the mid-90's. Natural oscillations like the PDO and AMO can impact shorter term  rates of decline.  But the long term decline is a result of rising global and Arctic temperatures.

https://www.pik-potsdam.de/members/feulner/research/how-would-a-new-grand-minimum-of-solar-activity-affect-the-future-climate

We simply have a difference of opinion here on what is causing the decline based on the research and info out there. As I've presented in other posts and threads there are various papers that have been written on alternative explanations for the ice decline that assert CO2 has had a minimal role and other factors or combinations of them are at play. We also need to consider what is "normal" for ice extent and coverage as well since throughout history there have been some significant changes to the ice extent, temperature distribution, etc. as the earth's climate has changed. That's quite obvious from the areas where glaciers are melting and revealing tree stumps and human civilization artifacts that quite clearly indicate much warmer temperatures in those regions in times past. 

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1 hour ago, bdgwx said:

That is not what bluewave or anyone has claimed. The claim is that Sun (like any main sequence star) is relatively stable in regards to it's luminosity. The variability in the radiative forcing is relatively small despite the magnitude of the radiative forcing being large. The change in radiative forcing of CO2 dominates over the change in radiative forcing of the Sun. Again, it's the change in the effects that are crucial in understanding the change in radiative forcing and thus the change in the heat uptake by the geosphere. Note that I have underlined change to drive home the point that it is the change in the system that puts pressure on the climate and ultimately the Arctic sea ice extents to also change.

For example, if the Sun were to experience a change of 0.25% in it's integrated luminosity then this is equivalent to 1360 W/m2 * 0.0025 / 4 = 0.85 W/m2 of forcing. But, a doubling of CO2 results in 5.35 * ln(560/280) = 3.7 W/m2 of forcing. That's more than 4x the effect. Plus, solar grand minimums are relatively short term compared to the long term impacts of CO2 which take 100s or even 1000s of years to die off to preindustrial levels. Note that a -0.25% change in TSI is considered to be on the high end of the forcing change for a hypothetical grand minimum.

The only problem with this assumption is that it assumes there are absolutely no other feedback created by this warming which may offset it in a positive/negative way as well.  There have been various papers written dealing with just this and it's not quite as cut and dry as it would seem. Water vapor, cloud cover, changes in ocean currents, etc. all create complex interactions that can lower or increase the effect of CO2 doubling.

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12 minutes ago, forkyfork said:

science doesn't care about your opinion 

Certainly not but science is a field where theories and our understanding of things is constantly evolving. There is plenty of scientific research which supports the opinion I have and there is scientific research supportive of other views as well. Scientific consensus is a great thing but can also be a big problem that holds back scientific advancement as well. For example, there have been cases where the scientific community held a consensus view and peer reviewed literature rejected other theories because they didn't agree with the consensus and yet the "minority" view ended up finally having a breakthrough that completely upset the "consensus" view. Do some research on this and you'll see what I mean. Skepticism and asking tough questions is a part of the process and differing views based upon scientific research should not automatically be discredited or rejected simply because they don't fit the "consensus" view; they are to be evaluated and examined. You would do well to study the agenda behind AGW btw, it's quite interesting to note and is worth keeping in mind.

Here's a quote to get you started by Stephen Schneider “On the one hand, as scientists we are ethically bound to the scientific method, on the other hand, we are not just scientists, but human beings as well. And like most people, we’d like to see the world a better place, which in this context translates into our working to reduce the risk of potentially disastrous climatic change. To do that, we need to get some broad-based support, to capture the public’s imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of the doubts we might have. Each of us has to decide what the right balance is between being effective and being honest.

Or how about this one?

If you think that [Yale professor James] Saiers is in the greenhouse skeptics camp, then, if we can find documentary evidence of this, we could go through official [American Geophysical Union] channels to get him ousted [as editor-in-chief of the Geophysical Research Letters journal].”

How about this?

“I can’t see either of these papers being in the next IPCC report. Kevin [Trenberth] and I will keep them out somehow---even if we have to redefine what the peer review literature is." 

Or this?

"I got a paper to review (submitted to the Journal of Agricultural, Biological and Environmental Sciences), written by a Korean guy and someone from Berkeley, that claims that the method of reconstruction that we use in dendroclimatology (reverse regression) is wrong, biased, lousy, horrible, etc…If published as is, this paper could really do some damage…It won’t be easy to dismiss out of hand as the math appears to be correct theoretically… I am really sorry but I have to nag about that review—Confidentially, I now need a hard and if required extensive case for rejecting.”

" IPCC official Ottmar Edenhofer, speaking in November 2010, advised that: “…one has to free oneself from the illusion that international climate policy is environmental policy.  Instead, climate change policy is about how we redistribute de facto the world’s wealth..." More info herehttps://www.forbes.com/sites/larrybell/2013/02/05/in-their-own-words-climate-alarmists-debunk-their-science/#4cecd56f68a3

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5 hours ago, BillT said:

"A solar minimum is no match for the CO2 forcing"......that is the claim made that clearly is saying co2 is more powerful than the SUN.......

Hmm...I think there may still be some confusion here. When we say "forcing" we are talking about a perturbation or anomaly above or below a reference point. 

For example, a solar grand maximum might have +1.0 W/m2 of "forcing" relative to a long term average. A solar grand minimum might have -1.0 W/m2 of "forcing" relative to the same long term average.

Likewise, CO2 "forcing" is relative to a reference point. Typically we use the 280 ppm preindustrial concentration as the reference point.

There's actually a coincidental and rather convenient temporal alignment of these two reference points as a result of the Sun being midway between the Maunder Minimum and Modern Maximum just before the CO2 concentrations spiked up from 280 ppm.

A "forcing" in this context is a change. We aren't saying that the total effect of CO2 is more powerful than the total effect of the Sun. What we are saying is that the change in the CO2 effect is bigger than the change in the Sun effect today. So if the Sun goes -1.0 W/m2 and CO2 goes +2.0 W/m2 and all other things remain equal then the net effect is +1.0 W/m2. This is because the change in the CO2 effect was bigger than the change in the Sun effect.

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7 hours ago, bluewave said:

A solar minimum is no match for the CO2 forcing. There was a good paper out on this several years ago. As for the AMO, the sea ice was in decline during the last cold phase during the 80's into the mid-90's. Natural oscillations like the PDO and AMO can impact shorter term  rates of decline.  But the long term decline is a result of rising global and Arctic temperatures.

https://www.pik-potsdam.de/members/feulner/research/how-would-a-new-grand-minimum-of-solar-activity-affect-the-future-climate

The sun has far more power on our planet than CO2, it borders on ridiculous to suggest otherwise.  That study is not powered well, and I'm pretty sure that institution has been known to push agendas for funding purposes in the past.  The only thing that has a remotely higher impact on us than the sun are things like drastic changes in oceanic composition and planetary events like super volcanoes and meteors.  I don't mean to come across too critical, you just seem too set in your ways.

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17 minutes ago, Save the itchy algae! said:

The sun has far more power on our planet than CO2, it borders on ridiculous to suggest otherwise.  That study is not powered well, and I'm pretty sure that institution has been known to push agendas for funding purposes in the past.  The only thing that has a remotely higher impact on us than the sun are things like drastic changes in oceanic composition and planetary events like super volcanoes and meteors.  I don't mean to come across too critical, you just seem too set in your ways.

Yes but the changes in solar output are much smaller in effect on radiative forcing than the cumulative influence of rapidly rising atmospheric CO2 concentrations.

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