Learning Global Warming facts and fiction

[Jimmy Hypocracy]

This is nothing new, the "Arctic is melting and the end of the world is coming" has been going on for 80+ years now. Archives of old newspaper articles reveal this quite well.

At the time these articles were written, sea ice extent is similar to what we have now... yet as we know within about 30 years the levels recovered to the peak in the 70s before another downtrend cycle started. It almost seems like there are natural factors at play here...

It's almost like the extreme heat in Europe has happened before and the news media hyped things like they always do.

And here was the drought index for 1934 per NOAA, at a time when PPM levels were around 310ppm.

I'm still waiting for the ice free Arctic predictions to materialize since at least 1923.

Meanwhile, in the 1970s when the ice reached the peak levels we've seen in the past 100 years, the tone shifted to an "Ice Age is Coming" fear. Ironically, this article was published by The Guardian as well.

Good work. History tends to repeat itself. The only difference is, those in the AGW department will say the trend in colder temperatures is due to AGW instead of saying “Space Satelites Show New Ice Age Coming Fast.” They won’t make that mistake again.

In the year 2018; Cold temperatures = Global Warming and Hot Temperatures = Global Warming

 

[GaWx]

So, here's my question. Did Charlotte's station move during 1980-2017 to a location with better radiational cooling while Raleigh's didn't? If so, that could explain why Charlotte mins were ~flat (cooling due to better radiation cancelled out by continued warming of mins due to GW) and would explain why Charlotte maxes as well as both Raleigh mins and maxes continued to warm (due to GW).

Further to the above curiosity about whether or not Charlotte's station moved to a better radiational cooling environment:

Years 2000+:
A. Charlotte
- 83 days with record low mins (high for only 18 years vs 122 years prior, the big mystery! See below)
- 79 days with record high maxes (high for only 18 years vs 122 years prior; I assume caused by continued GW)

B. Raleigh:
- 33 days with record low mins (low for 18 years vs 122 years prior I assume caused by continued GW)
- 99 days with record high maxes (quite high for only 18 years vs 122 years prior I assume caused by continued GW)

C. Lumberton:
- 23 days with record low mins (low for 18 years vs 97 years prior I assume caused by continued GW )
- 69 days with record high maxes

See the disconnect? How can both Raleigh and Lumberton have so many more record high maxes than record low mins 2000+ but Charlotte have about the same number (actually a few more record low mins)(Also, keep in mind that Lumberton is way smaller)?? Based on this as well as the flat lining of average lows at Charlotte during 1980-2017, I hypothesize that Charlotte's station was changed in some way that resulted in a better radiational cooling environment sometime after the 1980s.
Does @1300m, @snowlover91, or anyone else know if this occurred?

***edited several times

 

[EastAtlwx]

Check this out!

 

[snowlover91]

@GaWx Unfortunately I could not find any info about the Charlotte station to suggest if it was relocated or not. Certainly the results you analyzed are quite puzzling!

Meanwhile melt season in Greenland is done. How did we do? Not bad, we were well above the 1981-2010 average and close to the upper end of things. The chart resets September 1st but here’s how we stand right now.


Here is SMB gain/loss from September 1st, 2017 to today.


Meanwhile the Arctic ice thickness and overall volume has shown a nice recovery this year. It’s above the 2004-2013 mean and right behind 2014. The next few weeks will be critical to see if this levels off or storms/ridging melt off any additional areas.


And here’s 2014 for comparison. Notice all the ice piled up along the coastline which I assume was driven there by wind/storms.

 

[GaWx]

Interesting data Larry. To piggyback off your post, I compared some NOAA graphs for Charlotte vs RDU min temperatures, the results were not what I expected.
View attachment 5645
View attachment 5646

What does all this mean? Who knows but it sure is interesting to see the variability. Could it be that Charlotte has reached a point where the heat island affect is “baked in” and no longer continues to contribute to warming, thus the slight cooling in min temperatures? Perhaps this would then explain why Raleigh has a continued uptrend in min temps as it hasn’t hit that point yet (and Lumberton too) while a very rural area like Cherokee county has seen cooling? I also wonder what the raw data would show for these areas? Here’s the link I use to generate the above graphs in case you want to try it out. https://www.ncdc.noaa.gov/cag/city/time-series

Thanks to Eric's post in the August thread, we now have the answer:
http://southernwx.com/community/threads/august-rush.409/page-18#post-104543

Eric said: "Before they moved the sensor in 1998, Charlotte used to have the highest nighttime low temperatures in the region."

Starting then, it became one of the coldest in the area for nighttime lows even as daytime highs didn't cool. Actually, annual average highs have continued to slowly warm consistent with global warming and similar to most every other major reporting station vs the 1980s. As mentioned earlier, November had by far the strongest cooling of lows there of any month since the 1980s. Some months actually still had slightly warmer lows since the 1980s despite the more conducive to radiational cooling new location in 1998. Had the station not moved, Charlotte (like Raleigh and Lumberton) would have shown an overall warming since the 1980s due to global warming.

 

[snowlover91]

Thanks to Eric's post in the August thread, we now have the answer:
http://southernwx.com/community/threads/august-rush.409/page-18#post-104543

Eric said: "Before they moved the sensor in 1998, Charlotte used to have the highest nighttime low temperatures in the region."

Starting then, it became one of the coldest in the area for nighttime lows even as daytime highs didn't cool. Actually, annual average highs have continued to slowly warm consistent with global warming and similar to most every other major reporting station vs the 1980s. As mentioned earlier, November had by far the strongest cooling of lows there of any month since the 1980s. Some months actually still had slightly warmer lows since the 1980s despite the more conducive to radiational cooling new location in 1998. Has the station not moved, Charlotte (like Raleigh and Lumberton) would have shown an overall warming since the 1980s due to global warming.

Interesting. So then another unanswered question would be why some rural areas in NC have exhibited a gradual cooldown, like the Cherokee station which has been cooling for awhile now? This might indicate all warming at Raleigh, Charlotte and Lumberton is due to increasing urbanization/heat island effect while rural areas like Cherokee aren’t experiencing any changes thus showing the real trend? There’s a lot of variables of course when looking at individual cities and micro climates that can do strange things to sensors. I know Greg Fishel, a local met, is always very critical of the Raleigh station because of where the sensor is positioned and how hot it runs as a result.

 

[snowlover91]

Found some interesting data tonight. Someone took the sea ice extent reconstruction chart and added the AMO index at the bottom for comparison. It sure does seem like the AMO phases have a big role in sea ice extent in the Arctic especially when they are sustained for a few decades.

 

[GaWx]

Interesting. So then another unanswered question would be why some rural areas in NC have exhibited a gradual cooldown, like the Cherokee station which has been cooling for awhile now? This might indicate all warming at Raleigh, Charlotte and Lumberton is due to increasing urbanization/heat island effect while rural areas like Cherokee aren’t experiencing any changes thus showing the real trend? There’s a lot of variables of course when looking at individual cities and micro climates that can do strange things to sensors. I know Greg Fishel, a local met, is always very critical of the Raleigh station because of where the sensor is positioned and how hot it runs as a result.

1. Interesting. I don't have the answer about Cherokee. Do you have a link to the station? I'd love to dig deeply into it year by year and month by month, if possible, like I did for Charlotte.
2. I don't think of Lumberton as being large enough for most of its warming since the 1980s to have been due to UHI. So, you think it is large enough and has grown fast enough since the 1980s to mean an increased UHI causing its nighttime lows to increase?
3. The frequency of high max records at Raleigh and Charlotte have also been rising. I thought the UHI normally affects nighttime lows much more. How do you explain those?
4. I also wouldn't be surprised if increased UHI has been a significant factor in warming lows at Raleigh and Lumberton, but what about their highs also rising?

 

[GaWx]

Found some interesting data tonight. Someone took the sea ice extent reconstruction chart and added the AMO index at the bottom for comparison. It sure does seem like the AMO phases have a big role in sea ice extent in the Arctic especially when they are sustained for a few decades.
View attachment 5696

IF the Arctic ice extent and volume of the 1920s-1930s were truly about as low as recent years like this ice extent reconstruction shows, then that along with your ideas about increased UHI effect would start to make me wonder. But, how on earth (pun not intended) can we possibly know that this is accurate? And what about increasing sea levels over the last few decades? I've heard about many more tidal floods of the road to the beach near here vs when I was a kid in the 60s-70s and apparently they are more frequent than anytime since the road was built (1930s I think).
If there were somehow some way to see Arctic temps above 80N from 1920-1939 and I could compare to recent years' very warm anomalies there, that would be awesome.

 

[pcbjr]

IF the Arctic ice extent and volume of the 1920s-1930s were truly about as low as recent years like this ice extent reconstruction shows, then that along with your ideas about increased UHI effect would start to make me wonder. But, how on earth (pun not intended) can we possibly know that this is accurate? And what about increasing sea levels over the last few decades? I've heard about many more tidal floods of the road to the beach near here vs when I was a kid in the 60s-70s and apparently they are more frequent than anytime since the road was built (1930s I think).
If there were somehow some way to see Arctic temps above 80N from 1920-1939 and I could compare to recent years' very warm anomalies there, that would be awesome.

Larry,
Typing is arduous, so pardon brevity.
Great post.
One question on tidal flooding on the road to your beach. How much development has occurred in that area since your youth? For example, in Jax, during that same time period, my old road to the beach (Palm Valley Road) used to be desolate and dry. Now, that road is full of estates and gated communities, built on what used to be swamp land and large discharge and recharge areas, and the area was a spiderweb of now nonexistent creeks that ran to the Intracoastal; due to construction there is less than half the natural drainage left, and that area floods a lot now. It's like a colander with half or more of its holes plugged up; water drains slower and stands in the process. I think it is not coincidence.
So, maybe some of our man-made issues are not wholly climate related. Not suggesting; just wondering in this instance.
Phil

 

[GaWx]

Larry,
Typing is arduous, so pardon brevity.
Great post.
One question on tidal flooding on the road to your beach. How much development has occurred in that area since your youth? For example, in Jax, during that same time period, my old road to the beach (Palm Valley Road) used to be desolate and dry. Now, that road is full of estates and gated communities, built on what used to be swamp land and large discharge and recharge areas, and the area was a spiderweb of now nonexistent creeks that ran to the Intracoastal; do to construction there is less than half the natural drainage left, and that area floods a lot now. It's like a colander with half or more of its holes plugged up; water drains slower and stands in the process. I think it is not coincidence.
So, maybe some of our man-made issues are not wholly climate related. Not suggesting; just wondering in this instance.
Phil

Zero development. In this case (US highway 80, the road to nearby beach), it has nothing to do with increased development. There’s still no development in the area that’s been getting flooded more frequently at spring tides. I’m talking purely about saltwater flooding. That portion of the road (4 miles long) is surrounded by marsh and a river. It is really beautiful to those who enjoy untouched land/water.

Here’s a short video clip of Highway 80 high tide flooding of 10/28/15, which occurred with no rainfall and no high winds:



Normally, one would see marsh grass to the left as well as to the right between the two sets of trees (near the power poles). You can see there’s no development in the area.

 

[pcbjr]

Zero development. In this case (US highway 80, the road to nearby beach), it has nothing to do with increased development. There’s still no development in the area that’s been getting flooded more frequently at spring tides. I’m talking purely about saltwater flooding. That portion of the road (4 miles long) is surrounded by marsh and a river. It is really beautiful to those who enjoy untouched land/water.

Here’s a short video clip of Highway 80 high tide flooding of 10/28/15, which occurred with no rainfall and no high winds:



Normally, one would see marsh grass to the left as well as to the right between the two sets of trees (near the power poles). You can see there’s no development in the area.

Like I said ... was just a question. Obviously not a good one, though ...
Beautiful.
Preserve it.

 

[snowlover91]

1. Interesting. I don't have the answer about Cherokee. Do you have a link to the station? I'd love to dig deeply into it year by year and month by month, if possible, like I did for Charlotte.
2. I don't think of Lumberton as being large enough for most of its warming since the 1980s to have been due to UHI. So, you think it is large enough and has grown fast enough since the 1980s to mean an increased UHI causing its nighttime lows to increase?
3. The frequency of high max records at Raleigh and Charlotte have also been rising. I thought the UHI normally affects nighttime lows much more. How do you explain those?
4. I also wouldn't be surprised if increased UHI has been a significant factor in warming lows at Raleigh and Lumberton, but what about their highs also rising?

Some great questions Larry!
1. Here is the link to Cherokee county. Going back to 1900, the max temp trend is flat and the average temperature overall is slightly down. Cherokee county is really rural and would have much less of a heat island influence, if any at all. Interestingly you can see a distinct warming, cooling and then warming period at Cherokee with a general slight cooling trend over the past 115+ years. Recently there has been some warming which is likely cyclical imo. Here’s the link if you want to play around with some years. https://www.ncdc.noaa.gov/cag/count...ase=10&firsttrendyear=1900&lasttrendyear=2017

2. I think Lumberton would definitely have seen enough growth and urbanization to increase and influence temperatures. It really doesn’t take much asphalt and new buildings to bring about an influence of even a few tenths of a degree. Other factors also contribute. Research has shown that grassy areas can be a little warmer than areas that are heavily wooded. The loss of trees due to logging and/or urbanization could be a factor as well.
3. As I understand it, UHI affects both daytime and nighttime temperatures. More focus is typically seen on the nighttime side of things since brutal heatwaves and the UHI effect lead to little relief at night. One interesting study in 2010 by NASA found that the UHI can effect temps as much as 22F as seen in Providence, RI. Here is a link to the full article, a worthwhile read.
https://www.nasa.gov/topics/earth/features/heat-island-sprawl.html

For example in Providence, here is the temp data vs the land development.




And here’s an example from another article analyzing an area with day and night temps analyzed. You can see clearly the day and night temps are both significantly affected.

Link to article http://www.deeproot.com/blog/blog-e...act-of-trees-on-the-urban-heat-island-effect#

4. I think the highs rising may be a combo of increasing urbanization and also it appears there has been a trend recently to warmer temperatures. This seems to be cyclical from my research and driven by various combinations of factors like ocean currents, solar influence, urbanization and deforestation, and other factors.

 

[GaWx]

I just happened to see this today for the first time. It (from 2014) claims that if just 11% of our world’s crop acres were to be changed to no tilling, the increased CO2 emissions into the air could be negated! Any opinions? I’d especially like to hear from any crop growers/farmers who post here. Is this feasible? Here’s the link:


https://www.pri.org/stories/2014-08-25/old-school-farming-methods-could-save-planet

 

[snowlover91]

IF the Arctic ice extent and volume of the 1920s-1930s were truly about as low as recent years like this ice extent reconstruction shows, then that along with your ideas about increased UHI effect would start to make me wonder. But, how on earth (pun not intended) can we possibly know that this is accurate? And what about increasing sea levels over the last few decades? I've heard about many more tidal floods of the road to the beach near here vs when I was a kid in the 60s-70s and apparently they are more frequent than anytime since the road was built (1930s I think).
If there were somehow some way to see Arctic temps above 80N from 1920-1939 and I could compare to recent years' very warm anomalies there, that would be awesome.

Here’s one graph illustrating how temps in the 1920-40 range were similar to what we see today.

Here’s another look at the AMO cycle. The positive phases seem to coincide with reduced arctic ice and warmer temperatures.


Regarding the sea level rise, there are some interesting studies out there on this. One such is below which indicates many beaches have remained steady or gained while about 24% have been losing ground.
https://www.nature.com/articles/s41598-018-24630-6


This study likewise indicated we’ve been seeing a net increase instead of decrease, some of which is attributed to human activity in building up shorelines.

“Coastal areas were also analysed, and to the scientists surprise, coastlines had gained more land - 33,700 sq km (13,000 sq miles) - than they had been lost to water (20,100 sq km or 7,800 sq miles).

‘We expected that the coast would start to retreat due to sea level rise, but the most surprising thing is that the coasts are growing all over the world,’ said Dr Baart.

‘We're were able to create more land than sea level rise was taking.’”
https://www.bbc.com/news/science-environment-37187100

I believe much coastal flooding, sea level rises or falls are primarily due to various fluctuations such as increased storms, land subsidence or increase, volcanic influence, and other factors. Here’s one final interesting article.
Kench et al., 2018
“We specifically examine spatial differences in island behaviour, of all 101 islands in Tuvalu, over the past four decades (1971–2014), a period in which local sea level has risen at twice the global average (Supplementary Note 2). Surprisingly, we show that all islands have changed and that the dominant mode of change has been island expansion, which has increased the land area of the nation. … Using remotely sensed data, change is analysed over the past four decades, a period when local sea level has risen at twice the global average [<2 mm/yr-1] (~3.90 ± 0.4 mm.yr−1). Results highlight a net increase in land area in Tuvalu of 73.5 ha (2.9%), despite sea-level rise, and land area increase in eight of nine atolls.

 

[Webberweather53]

Here’s one graph illustrating how temps in the 1920-40 range were similar to what we see today.
View attachment 5701
Here’s another look at the AMO cycle. The positive phases seem to coincide with reduced arctic ice and warmer temperatures.
View attachment 5702

Regarding the sea level rise, there are some interesting studies out there on this. One such is below which indicates many beaches have remained steady or gained while about 24% have been losing ground.
https://www.nature.com/articles/s41598-018-24630-6
View attachment 5703

This study likewise indicated we’ve been seeing a net increase instead of decrease, some of which is attributed to human activity in building up shorelines.

“Coastal areas were also analysed, and to the scientists surprise, coastlines had gained more land - 33,700 sq km (13,000 sq miles) - than they had been lost to water (20,100 sq km or 7,800 sq miles).

‘We expected that the coast would start to retreat due to sea level rise, but the most surprising thing is that the coasts are growing all over the world,’ said Dr Baart.

‘We're were able to create more land than sea level rise was taking.’”
https://www.bbc.com/news/science-environment-37187100

I believe much coastal flooding, sea level rises or falls are primarily due to various fluctuations such as increased storms, land subsidence or increase, volcanic influence, and other factors. Here’s one final interesting article.
Kench et al., 2018
“We specifically examine spatial differences in island behaviour, of all 101 islands in Tuvalu, over the past four decades (1971–2014), a period in which local sea level has risen at twice the global average (Supplementary Note 2). Surprisingly, we show that all islands have changed and that the dominant mode of change has been island expansion, which has increased the land area of the nation. … Using remotely sensed data, change is analysed over the past four decades, a period when local sea level has risen at twice the global average [<2 mm/yr-1] (~3.90 ± 0.4 mm.yr−1). Results highlight a net increase in land area in Tuvalu of 73.5 ha (2.9%), despite sea-level rise, and land area increase in eight of nine atolls.
View attachment 5704

Surface temperature reconstructions in the arctic are lol before the satellite era.

 

[snowlover91]

Surface temperature reconstructions in the arctic are lol before the satellite era.

Historical observations, reports from numerous sources and other data all corroborate a warm Arctic in the 1920-1945 period and significantly reduced sea ice. The below link has one of the more extensive analysis I’ve seen on the subject.
https://judithcurry.com/2013/04/10/historic-variations-in-arctic-sea-ice-part-ii-1920-1950/

One such example is listed below from the above article.
“During the last three decades there has been a marked change in the climate of the Arctic which is being felt throughout the northern hemisphere where, especially, the mean temperature of the winters has increased considerably. In the North American sector this change is perhaps best understood and also most marked in Greenland, where long meteorological records exist from a number of points on the west coast, Thus at Jakobshavn, in latitude 690 13 North, the mean winter temperature for the years 1913-1922 was about 5 degrees F above the mean of 50 years and that of 1923-1932 almost 10.0 degrees F. above. In 1935-1936 the mean for the winter at Godhavn was 13.40 higher than the normal at the end of last century, that of Godthaab 7.60 and at Julianehaab 9.8oF. Increasing temperatures are not limited to the air; sea temperatures also have increased and while the amplitude is not so great, the result is even more profound and far reaching.”

 

[Webberweather53]

Historical observations, reports from numerous sources and other data all corroborate a warm Arctic in the 1920-1945 period and significantly reduced sea ice. The below link has one of the more extensive analysis I’ve seen on the subject.
https://judithcurry.com/2013/04/10/historic-variations-in-arctic-sea-ice-part-ii-1920-1950/

My point is there are hardly any surface observations compared to the modern era and even if you tried to make the case that temperatures or sea ice were somehow similar, the coverage and quality of observations is so poor I wouldn't deem it very reliable to draw any conclusion or analyses from it (even Sea Ice charts), because the error bars are so massive especially on the Pacific and Russian sides of the arctic which often went unreported, proxy reconstructions also only get you so far. I'm also curious if you actually looked into what the error bars were on the sea ice chart you linked above because they may be as large or larger than the signal you're trying to claim exists. The HADISST2 dataset recently released by Kennedy et al primarily uses the annual cycle before 1973 to assess sea ice variability because we don't really know w/ the kind of confidence you're trying to suggest regarding arctic sea ice. Most of the observations before passive microwave satellite imagery in the early-mid 1970s are from the occasional passing ship report and even still, most of those ships would sail away from the ice pack to avoid sinking, only observed an exceptionally small area of the marginal ice zone, and they were highly subjective, fraught w/ appreciable larger error per capita & area vs satellites.

It's also important that you approach this objectively and not as you're currently doing via hunting and pecking for data to validate your preconceived notions and ideas of how ice should vary accordance w/ natural variability only, while completely ignoring or downplaying the anthropogenic component which most agree is important to consider (but also difficult to model, this doesn't mean however it doesn't exist). You'll find that it's actually pretty easy for someone like yourself who knows just enough on the topic to find be "dangerous" and come across certain talking points, excerpts, and/or sound bites from particular pieces of literature or blogs w/o looking at what the overall scientific community and climate scientists are really saying on this issue. You may completely ignore this last piece of advice/information, but I was in your shoes saying and looking for these exact things on topics like sea ice only several years ago and was a frequent blogger on WUWT and Real Science (which are terrible places to get reliable, unbiased information on AGW from professionals in the field). Looking back, I wish I had approached this problem more objectively, w/ less negative fervor against those touting AGW because the overwhelming majority of them hold more moderate, "reasonable" views on AGW than what some "skeptics" want you to believe. I'm certainly not labeling you as someone who does this and don't take it that way, but when I see many "deniers" & "alarmists" alike (especially those w/o secondary education on this topic) having to take a look towards the extreme ends of the spectrum to validate their own stance on AGW, it says a lot about what they actually know w/ AGW and how uncomfortable/uncertain they truly are deep down about their own views.

 

[Webberweather53]

Historical observations, reports from numerous sources and other data all corroborate a warm Arctic in the 1920-1945 period and significantly reduced sea ice. The below link has one of the more extensive analysis I’ve seen on the subject.
https://judithcurry.com/2013/04/10/historic-variations-in-arctic-sea-ice-part-ii-1920-1950/

One such example is listed below from the above article.
“During the last three decades there has been a marked change in the climate of the Arctic which is being felt throughout the northern hemisphere where, especially, the mean temperature of the winters has increased considerably. In the North American sector this change is perhaps best understood and also most marked in Greenland, where long meteorological records exist from a number of points on the west coast, Thus at Jakobshavn, in latitude 690 13 North, the mean winter temperature for the years 1913-1922 was about 5 degrees F above the mean of 50 years and that of 1923-1932 almost 10.0 degrees F. above. In 1935-1936 the mean for the winter at Godhavn was 13.40 higher than the normal at the end of last century, that of Godthaab 7.60 and at Julianehaab 9.8oF. Increasing temperatures are not limited to the air; sea temperatures also have increased and while the amplitude is not so great, the result is even more profound and far reaching.”

Natural variability is actually capable of being quite large on a local level (temperatures in MN during the winter of 1877-78 were 4F warmer than the next closest winter (1997-98) but that doesn't necessarily reflect the overall global response relative to the late 20th century) and in the case of the arctic because the moist static energy budget is so low, temperature variance is very large in comparison to the rest of the globe, thus large anomalies like this aren't as unheard of. The reality is, apart from a few very sparse and poorly constrained data points like what you're alluding to above, there's not much we can really say about surface temperatures in the entire arctic during this period, there have been many attempts to reconstruct the data their w/ little-no avail, and/or they haven't been taken seriously by many in the scientific community (& rightfully so). The quality and coverage of surface data in the arctic during the 1920s and 30s is comparable to the RAOB network during WW II, I wouldn't necessarily consider either very reliable but some very basic signals could potentially be cast. However, to go as far as to say it's as warm or warmer than the 21st century is definitely a stretch especially w/o first recognizing or respecting the error bars involved in these kind of early analyses & measurements. Even GISS, which uses ridiculous amounts of kriging and interpolation to encapsulate the arctic during their month analyses, notes the coverage & confidence of surface observations even in the present day is very poor, you could obviously imagine it's not any better in the early-mid 20th century.

 

[pcbjr]

My point is there are hardly any surface observations compared to the modern era and even if you tried to make the case that temperatures or sea ice were somehow similar, the coverage and quality of observations is so poor I wouldn't deem it very reliable to draw any conclusion or analyses from it (even Sea Ice charts), because the error bars are so massive especially on the Pacific and Russian sides of the arctic which often went unreported, proxy reconstructions also only get you so far. I'm also curious if you actually looked into what the error bars were on the sea ice chart you linked above because they may be as large or larger than the signal you're trying to claim exists. The HADISST2 dataset recently released by Kennedy et al primarily uses the annual cycle before 1973 to assess sea ice variability because we don't really know w/ the kind of confidence you're trying to suggest regarding arctic sea ice. Most of the observations before passive microwave satellite imagery in the early-mid 1970s are from the occasional passing ship report and even still, most of those ships would sail away from the ice pack to avoid sinking, only observed an exceptionally small area of the marginal ice zone, and they were highly subjective, fraught w/ appreciable larger error per capita & area vs satellites.

It's also important that you approach this objectively and not as you're currently doing via hunting and pecking for data to validate your preconceived notions and ideas of how ice should vary accordance w/ natural variability only, while completely ignoring or downplaying the anthropogenic component which most agree is important to consider (but also difficult to model, this doesn't mean however it doesn't exist). You'll find that it's actually pretty easy for someone like yourself who knows just enough on the topic to find be "dangerous" and come across certain talking points, excerpts, and/or sound bites from particular pieces of literature or blogs w/o looking at what the overall scientific community and climate scientists are really saying on this issue. You may completely ignore this last piece of advice/information, but I was in your shoes saying and looking for these exact things on topics like sea ice only several years ago and was a frequent blogger on WUWT and Real Science (which are terrible places to get reliable, unbiased information on AGW from professionals in the field). Looking back, I wish I had approached this problem more objectively, w/ less negative fervor against those touting AGW because the overwhelming majority of them hold more moderate, "reasonable" views on AGW than what some "skeptics" want you to believe. I'm certainly not labeling you as someone who does this and don't take it that way, but when I see many "deniers" & "alarmists" alike (especially those w/o secondary education on this topic) having to take a look towards the extreme ends of the spectrum to validate their own stance on AGW, it says a lot about what they actually know w/ AGW and how uncomfortable/uncertain they truly are deep down about their own views.

Webb,
Sometimes we disagree and other times not, but one thing I'm sure we all consistently concur on ... you've really learned to write and make a stout point ... and for that I truly laud you ...
Best!
Phil