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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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The issue doesn’t mean measuring sea ice extent or area is not science. The issue concerns limitations of satellite-based measurements and the concept of margins of error. Statistically, when error is considered, measurements within 40,000 km2 are treated as being the same.<<<

TY so now we have a large margin of error when taking a picture and measuring it, YET your side still claims to have precision in a single global temperature to within hundredths of a degree.....and no mention of any margin of error in those claims.

bottom line = the claims we humans are the cause of climate change is IDIOCY and not one shred of science backs that claim.

 

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12 minutes ago, BillT said:

The issue doesn’t mean measuring sea ice extent or area is not science. The issue concerns limitations of satellite-based measurements and the concept of margins of error. Statistically, when error is considered, measurements within 40,000 km2 are treated as being the same.<<<

TY so now we have a large margin of error when taking a picture and measuring it, YET your side still claims to have precision in a single global temperature to within hundredths of a degree.....and no mention of any margin of error in those claims.

bottom line = the claims we humans are the cause of climate change is IDIOCY and not one shred of science backs that claim.

 

Monthly and annual temperature errors within a greater than 95% confidence interval were very small 0.1 to 0.2 degrees C back in 2013.

http://static.berkeleyearth.org/memos/robert-rohde-memo.pdf

Since then, better ocean measurements have become available and the averaging errors are even smaller. Even at the earlier figures, one could reject the null hypothesis that the global climate had not warmed at a 95% level of confidence.

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20 minutes ago, BillT said:

plus or minus .1 degreeC does NOT give one accuracy to within hundredths of a degree.

Averaging can lead to numbers in tenths, hundredths, thousandths of degrees even if the averaged numbers are whole numbers. For example, assume there is a hypothetical 1,000 stations. All but 1 record 50 degree readings. One registers a 51 degree reading. The average is 50.001 degrees, even as no thermometers measure temperature in thousandths of degrees.

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28 minutes ago, BillT said:

you example above gives an average NOT a meaningful single average for that area.......nowhere in that area likely was 50.001, so that number in reality has no useful info or meaning

Global average temperatures and anomalies are not a single area temperature/anomaly. They are measured in thousands of areas on land and in the ocean. Thus, the hypothetical scenario, which was meant to illustrate the concept of averages in thousandths of degrees, is spot on.

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spot on yes averages can be taken out that many places but that is NOT what i am discussing, my POINT is the ACCURACY of those averages is nothing  close to the precision needed to claim accuracy to within hundredths of a degree..... in summary yes you can average many number out to many decimals places but that is NO WAY means the final result is an accurate scientific reading.

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3 minutes ago, BillT said:

spot on yes averages can be taken out that many places but that is NOT what i am discussing, my POINT is the ACCURACY of those averages is nothing  close to the precision needed to claim accuracy to within hundredths of a degree..... in summary yes you can average many number out to many decimals places but that is NO WAY means the final result is an accurate scientific reading.

I provided one paper earlier that dealt with the accuracy issue. The temperature data can be relied on with a very high degree of confidence.

At 2 sigma (> 95% confidence), the error is around 0.1°C (e.g., for GISS). Thus, for example, the decadal average mean anomaly during the last 10 years on GISS (+0.78°C) clearly was warmer than that during the 1990s (+0.39°C). The difference between the two 10-year periods was so great that one was dealing with > 99.9% confidence. Statistically, arguments that the 1990s were just as warm (or warmer) are inaccurate.

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4 hours ago, BillT said:

The issue doesn’t mean measuring sea ice extent or area is not science. The issue concerns limitations of satellite-based measurements and the concept of margins of error. Statistically, when error is considered, measurements within 40,000 km2 are treated as being the same.<<<

TY so now we have a large margin of error when taking a picture and measuring it, YET your side still claims to have precision in a single global temperature to within hundredths of a degree.....and no mention of any margin of error in those claims.

bottom line = the claims we humans are the cause of climate change is IDIOCY and not one shred of science backs that claim.

 

That statement is idiotic. 

And literally every scientist on the planet agrees that we are the cause but do enlighten us.

And Don please don't even waste your time. 

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amazing....the climate always changes, it is a set of statistics used to describe the past weather and used to predicts what is the normal conditions now......those statistics constantly change so their output will also constantly change.......to claim we humans CAUSE these climate changes indeed is NOT science and is rather NON thinking on any level.......mock me all you desire but i post truth in laymans terms........the weather constantly changes and i assure YOU we humans are NOT the cause of constantly changing weather.

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6 hours ago, BillT said:

amazing....the climate always changes, it is a set of statistics used to describe the past weather and used to predicts what is the normal conditions now......those statistics constantly change so their output will also constantly change.......to claim we humans CAUSE these climate changes indeed is NOT science and is rather NON thinking on any level.......mock me all you desire but i post truth in laymans terms........the weather constantly changes and i assure YOU we humans are NOT the cause of constantly changing weather.

That the climate is dynamic (has always changed and would continually change absent an anthropogenic influence) does not mean that humans aren't the predominant driver of the contemporary change. The evidence of the dramatic ongoing warming and the anthropogenic nature are overwhelming and unequivocal.

Solar irradiance has not materially increased since 1950. Global temperatures have decoupled from solar irradiance. Unlike with a solar driver, where all levels of the atmosphere warm on account of an increase in incoming shortwave radiation, the stratosphere has been cooling while the troposphere has been warming. That is a classic fingerprint of greenhouse gases emitting some of the earth's outgoing longwave radiation back to the surface. This imbalance is leading to warming.

http://www.ces.fau.edu/nasa/module-2/how-greenhouse-effect-works.php

The physical properties of carbon dioxide were discovered back in the 19th century. Their atmospheric concentration has increased dramatically from 316 ppm in 1959 to just under 409 ppm in 2018 at the Mauna Loa Observatory. No natural variables can explain this increase. Human emissions, not all of which are absorbed by carbon sinks, do. When atmospheric greenhouse gases are included, the recent warming is represented very well. There is a very high coefficient of determination between the greenhouse gases and temperature (as one would expect from the demonstrated physical properties of such gases).

https://climexp.knmi.nl/imageoftheweek.png

This strong relationship is part of the reason the shrinking minority who rejects the reality of anthropogenic climate change often attempt to discredit the temperature records. They have no scientifically-valid alternative explanation for the warming. Hence, they try to get around that barrier by discounting or denying the warming. Of course, even if no temperature record existed, trends in declining Arctic sea ice, migration of flora, general retreat of glaciers, rising sea level, etc., are all consistent with a warming world.

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6 hours ago, BillT said:

amazing....the climate always changes, it is a set of statistics used to describe the past weather and used to predicts what is the normal conditions now......those statistics constantly change so their output will also constantly change.......to claim we humans CAUSE these climate changes indeed is NOT science and is rather NON thinking on any level.......mock me all you desire but i post truth in laymans terms........the weather constantly changes and i assure YOU we humans are NOT the cause of constantly changing weather.

And the Earth is flat too. 

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On 9/11/2019 at 3:51 PM, ORH_wxman said:

 

Time to verify this prediction based on the data at the end of June.

 

Assuming we have reached the minimums for both area and extent on 9/4 (looking more and more likely), then both of these fell outside my range, albeit not by much. The final minimum area was 2.87 million sq km and the final minimum extent was 4.23 million sq km. These are both NSIDC numbers. The predictions were looking excellent through mid-August until we had an unprecedented slowdown in late August that has leaked into early September. So I ended up making predictions that were slightly too low compared to reality.

 

I was correct in identifying the very strong chance of a top 3 finish (and also being skeptical of challenging the top spot), but I really needed to bump my middle numbers in the range up about 100-200k. Overall, I think this was a decent prediction compared to what we see on the Arctic Sea Ice outlook that gets published by NSIDC....but I am still disappointed I could not get it within my range. It might be that 200k error bars are just too small to consistently hit on predictions when it comes to sea ice. Using 400k error bars would have this method hit every year I've done it with the exception of 2016. But I will probably try to continue to use 200k error bars....and maybe see where the method can be improved.

I should update this in that the NSIDC minimum extent dropped a bit further to 4.09 million sq km....still outside my range but a bit closer than the 4.23 initial value I posted above. Doesn't change the analysis above in any material way. The area minimum hasn't been matched again and will remain at 2.87....we're now over 300k sq km above the 9/4 area min so that won't be caught again. We'll see if 4.09 million sq km is the final minimum extent....still a chance it could fall back below that from the current 4.17 million sq km value, but it's getting very late now to significant drops.

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Very impressive Arctic Amplification  this September with so much open water.

https://www.arctictoday.com/arctic-sea-ice-is-close-to-its-annual-minimum-extent-but-thats-just-part-of-the-picture/?wallit_nosession=1

As the autumn equinox looms and winter darkness approaches, Arctic sea ice has dwindled to what appears to be one of the lowest minimums in the satellite record.

“We are basically right now in a dead tie for second place,” Mark Serreze, director of the National Snow and Ice Data Center, said on Wednesday.

Ice extent — defined as the area where there is at least 15 percent ice coverage — dropped to 4.1 million square kilometers on Tuesday, matching minimums set in 2007 and in 2016, according to the Colorado-based NSIDC.

It will take a few more days to know whether this year’s minimum has been set and the freeze season has started, Serreze said. Total ice extent can waver up and down at this time of the year because of shifting winds and a contest between freeze at the highest latitudes and continued melt in the more southern parts of the Arctic, he said.

This year’s minimum extent has no chance of matching the record-low 3.4 million square kilometers (1.32 million square miles) hit in 2012, Serreze said. Still, it fits into a trend to more open water over longer periods of the year, he said.

All that open water reinforces the warming cycle in the far north, strengthening the phenomenon known as Arctic Amplification, he said.

When waters lack ice cover, they absorb more solar heat, he said. “You’ve got to get rid of all that heat,” he said. “Where does that heat go? Up into the atmosphere.”

While annual minimums are useful markers for long-term trends, the expanding durations of open water are turning out to have more immediate significance, said Rick Thoman, climate scientist with the Alaska Center for Climate Assessment and Policy at the University of Alaska Fairbanks.

That is especially the case for the waters off Alaska — the Bering, Chukchi and Beaufort seas — where ice has been especially scarce, even in the past winters, he said. The official Arctic-wide minimum extent is only part of the picture, he said.

“For Alaska, it doesn’t make much of a difference if it’s No. 1 or No. 4. There hasn’t been any ice anywhere near Alaska for a very long time and the water that’s there is extremely warm,” Thoman said.

In the waters off northern and northwestern Alaska, sea-surface temperatures were generally running 3 to 6 degrees Celsius (5.4 to 10.8 degrees Fahrenheit) above normal during the second week of September, according to data gathered by ACCAP.

That sets the stage for a delayed freeze season, he said. “We can be absolutely certain that freeze-up in the Beaufort, Chukchi and at least the central Bering will be late,” he said.

Delayed freeze likely means a warmer-than-normal fall and, when the winter freeze arrives, ice that is thin and more susceptible to midwinter meltdowns similar to those that occurred in the past two years in the Bering and the Chukchi, he said.

The past years’ winter ice loss may have been highly unusual, but repeat occurrences could become more common if southerly winds return, Thoman said.

“I think you’ll see the big collapses like we’ve had in the past two years. That requires that sustained southerly flow. We won’t see that every year,” he said.

Thoman noted that with the exception of the extreme low in 2012, annual minimums over the past decade have been generally in the same ballpark.

That is because the very high-latitude ice, unlike ice at lower Arctic latitudes, has relatively brief period of the year when there is direct sunlight shining on it and causing melt from above, he said.

“We have melted all the easy, low-latitude ice now,” he said. Melting out ice at the highest latitudes will require a different process, he said. “That’s going to come from the ocean. That’s going to come from underneath,” he said.

Serreze, too, said the highest-latitude ice has lingered despite widespread melt elsewhere in the Arctic. At those very high latitudes — for now — there is still multiyear ice that survives melt seasons, he said.

But more changes are expected in the future, he said.

“We are kind of in new territory,” he said. “We have not been here before, so every year we’re learning.”

https://mobile.twitter.com/ZLabe/status/1175055129290010624

Well above average temperatures over nearly the entire #Arctic Ocean so far this September. This is especially found in areas where there is a lack of sea ice cover.

 

 
 

 

 

 

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15 minutes ago, bluewave said:

Very impressive Arctic Amplification  this September with so much open water.

...

 
 

 

 

 

The low sea ice and resulting Arctic amplification is a big reason why Utqiakvik (Barrow) had its latest first freeze on record (9/19 vs. the old record of 9/7) and has a chance of registering its first September with a mean temperature of 40° or above. The current monthly record is 37.7°.

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34 minutes ago, donsutherland1 said:

The low sea ice and resulting Arctic amplification is a big reason why Utqiakvik (Barrow) had its latest first freeze on record (9/19 vs. the old record of 9/7) and has a chance of registering its first September with a mean temperature of 40° or above. The current monthly record is 37.7°.

That’s a remarkable stat. Just saw it posted on twitter. Record warmth and high pressure over the Arctic since May.

https://mobile.twitter.com/AlaskaWx/status/1175034044578295808

https://mobile.twitter.com/ZLabe/status/1170022132216029185

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NSIDC extent dropped to the second lowest minimum on record. 2019 was effectively tied with 2016 and 2007.

https://nsidc.org/arcticseaicenews/

Table 1. Thirteen lowest minimum Arctic sea ice extents (satellite record, 1979 to present)
RANK YEAR MINIMUM ICE EXTENT DATE
IN MILLIONS OF SQUARE KILOMETERS IN MILLIONS OF SQUARE MILES
1 2012 3.39 1.31 Sept. 17
2 2019
2007
2016
4.15
4.16
4.17
1.60
1.61
1.61
Sept. 18
Sept. 18
Sept. 10
5 2011 4.34 1.68 Sept. 11
6 2015 4.43 1.71 Sept. 9
7 2008
2010
4.59
4.62
1.77
1.78
Sept. 19
Sept. 21
9 2018
2017
4.66
4.67
1.80
1.80
Sept. 23
Sept. 13
11 2014
2013
5.03
5.05
1.94
1.95
Sept. 17
Sept. 13
13 2009 5.12 1.98 Sept. 13

Values within 40,000 square kilometers (15,000 square miles) are considered tied. The 2018 value has changed from 4.59 to 4.66 million square kilometers (1.80 million square miles) when final analysis data updated near-real time data, dropping 2018 to a tied ninth position with 2017.

 

 

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On 9/21/2019 at 9:34 AM, donsutherland1 said:

One other statistic: Utqiagvik had 55 days with low temperatures of 40 or higher. The old record was 32.

And a frost free period of 85 days. Remarkable. One wonders what that's doing to the permafrost this year. Last few years the situation further south (near Fairbanks) has been bad enough that the active layer isn't completely refreezing during the winter, creating a layer of permanent thaw sandwiched in between. A situation which wasn't expected until quite a bit later in the century.

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7 hours ago, csnavywx said:

And a frost free period of 85 days. Remarkable. One wonders what that's doing to the permafrost this year. Last few years the situation further south (near Fairbanks) has been bad enough that the active layer isn't completely refreezing during the winter, creating a layer of permanent thaw sandwiched in between. A situation which wasn't expected until quite a bit later in the century.

Yesterday was also Utqiagvik's 94th day of the year above freezing (highlighted by the 85-consecutive day streak). That surpassed the previous mark of 93, which was set in 1998.

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13 hours ago, csnavywx said:

And a frost free period of 85 days. Remarkable. One wonders what that's doing to the permafrost this year. Last few years the situation further south (near Fairbanks) has been bad enough that the active layer isn't completely refreezing during the winter, creating a layer of permanent thaw sandwiched in between. A situation which wasn't expected until quite a bit later in the century.

Yeah I was reading about that a few months ago. It's another observation in a cornucopia that suggest unanticipated accelerations - to put it nicely. Changes are simply outpacing many model-designs of when/where we would begin noticing specific warming effects amid specific systems - quite possibly because the "Kevin Baconism" of the larger gestalt and sensitive transmitted relationships are just unknown.

It is ... disconcerting.  I feel - personally - with growing conviction, that there could be "jolt" events.  Scale and degree of "cataclysm" to be determined, but short duration adjustments that really didn't have much hope of being well predicted because they are/were brought about by previously unanticipated emerging "synergistic" feed-backs.   I read a paper once about the basal flow rates of Antarctic causing the land-based aspect of the western ice sheet to accelerate well beyond climate models, and something similar in Greenland may already be taking place. 

If these thing happen, then...relative too, even accelerate further - no one can say that can't happen, when acceleration is already empirical and that's pretty much adios muchachos global coastal environments when/if land based ice lets go en masse.  

 

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3 hours ago, Typhoon Tip said:

Yeah I was reading about that a few months ago. It's another observation in a cornucopia that suggest unanticipated accelerations - to put it nicely. Changes are simply outpacing many model-designs of when/where we would begin noticing specific warming effects amid specific systems - quite possibly because the "Kevin Baconism" of the larger gestalt and sensitive transmitted relationships are just unknown.

It is ... disconcerting.  I feel - personally - with growing conviction, that there could be "jolt" events.  Scale and degree of "cataclysm" to be determined, but short duration adjustments that really didn't have much hope of being well predicted because they are/were brought about by previously unanticipated emerging "synergistic" feed-backs.   I read a paper once about the basal flow rates of Antarctic causing the land-based aspect of the western ice sheet to accelerate well beyond climate models, and something similar in Greenland may already be taking place. 

If these thing happen, then...relative too, even accelerate further - no one can say that can't happen, when acceleration is already empirical and that's pretty much adios muchachos global coastal environments when/if land based ice lets go en masse.  

 

When serious, full political spectrum action plans are implemented, I wonder which floor of the UN building the floating docks will be moored to. As always ...

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Utqiagvik (formerly Barrow) remains on course for a record warm September. It is also increasingly likely to see its first September with a mean temperature of 40.0° or above. Overall, largely on account of low summer sea ice, resulting in Arctic amplification, the area has been warming very rapidly.

Utqiagvik-Sept1950-2019graph.jpg

September 2019 Mean: 39.7° - 40.8° (estimated)

September Record: 37.7°, 1998

1981-2010 Mean: 32.1°

30-Year Moving Average: 1990-2019: 33.5° (estimated)

Low Summer Ice Era: 2007-Present

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The EPO has wended its way into a negative phase state ... that’ll pretty much be the ballgame for the Alaskan sector as that’s a warm signal up there, and modeled to persist for the next week  

...meanwhile an early cold plume and upslope snow event becoming increasingly more likely in the lower latitude Canadian high country /interior PAC NW ... as immediate downstream of there is a typical mass balanced loading pattern - classic teleconnector correlation ...

There’s been a recurring theme over the last 15 years for unusually early cold and potential’s for snow in the middle latitudes of North America…very early.  I believe it’s part of the pacific heat budget and the swelling of the Hadley cell that’s been noted/papered. This is forcing the AB phase of the Pacific basin ... thus intrusion of NP/EP blocking. This resulting in organized R-wave geometries that are unusually proficient cold deliveries earlier in transition seasons. 
 


 

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Notice the much greater amplitude of the Arctic pressure pattern swings  since 1990. This would seem to match the 2009 corals study.The record summer Arctic dipole pattern from 2007 to 2012 and new lowest extent. Rapid reversal in 2013 and 2014. Then stronger dipole anomalies in 2016 and 2019. Continuation of the long term Arctic sea ice decline with very choppy volatility from year to year.

https://www.sciencedaily.com/releases/2009/01/090113101200.htm

Swings In North Atlantic Oscillation Variability Linked To Climate Warming

Anthropogenic (human-related) warming does not appear to be altering whether the NAO is in a positive or negative phase at multi-decadal time scales,” said WHOI paleoclimatologist Konrad Hughen. “It does seem to be increasing variability. Clearly, this has implications for the future.”

“As temperatures get warmer, there’s potential for more violent swings of the NAO — the phases becoming even more positive and even more negative,” Hughen added. “If the NAO locks more into these patterns, intense storms will become more intense and droughts will become more severe.”

 

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3 hours ago, donsutherland1 said:

NASA Goddard Space Flight Center video on this year's Arctic sea ice extent minimum:

 

 

“This Too Shall Pass” are four words that always gave me comfort. In reference to the video above I believe those four words are being answered by another four words: “Now You’ll Get Yours”. As always ......

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