Sea Surface Temperature And Sea Ice Trends

[parmenides3]

A quick update on the sea ice situation. Note that WIB has also postend in the 'latest' strand.

Approximate progress of ice melt from Cryosphere Today graphs: Figures are in Millions of square kilometres, and are only as accurate as I can read them.

Total ice cover:

July 13th - 7.5 Mkm2

July 20th - 7.4

July 24th - 7.0

July 29th - 6.5

Aug 7th - 6.25

The final minimum for the year is almost certain to fall somewhere between 5 and 6 Mkm2, so the trend towards less cover continues, the final anomaly figure being negative. It seems unlikely that this will be a 'record' year, but there is an unusually large area of low concentration stretching through the middle of the ice pack from the Chukchi Sea right across to the Canadian Archipelago. A spell of mild weather could yet accelerate melt in this area in particular.

:lol:

[parmenides3]

Some fairly hot news on the situation this year:

Record retreat of Arctic sea ice

This year's melting of Arctic summer sea ice is on track to be the most extreme since satellites began to track the polar ice cap in 1979, scientists at the National Snow and Ice Data Center on the University of Colorado campus say.

Source: Dailycamera.com (local Boulder Co. news).

SOCC website has also stated that current sea ice extent (which is different to sea ice cover) is already the lowest ever recorded, also that this is the fourth year in a row that the minimum extent record has fallen.

Had a quick check of the Cryosphere Today site, and that shows a sudden and rapid drop, below 5.9 M Km2, about 0.3 M lower than the same time last year. The anomaly is now greater than -1M Km2.

[West is Best]

minimum extent record has fallen.

Had a quick check of the Cryosphere Today site, and that shows a sudden and rapid drop, below 5.9 M Km2, about 0.3 M lower than the same time last year. The anomaly is now greater than -1M Km2.

Parmenides3 - really good posts on this thread. Just checked and you're absolutely right. The ice levels are falling to record minimum territory now. With around approx more weeks until the minimum date is reached this is pretty serious:

[parmenides3]

Absolutely, WIB. Trouble is, however hard I try to understand the dynamics of the sea ice, it still remains more a guessing game than a forecasting process. Keeping an eye on the various information sites is about the only way we can say what is happening, but even the best only update 1/3 of their information every day, so there is a time-lag between actual conditions and reports.

You previously posted a very neat diagnostic chart, which I can't find; any chance of an update? You may also have more luck than I had yesterday finding an up-to-date clear visual satellite image of the low concentration area in the North of the Beaufort Sea, which is where the largest 'pool' of melt appears to be taking place..

It is not beyond the bounds of possibility that we are currently observing the onset of a phase shift in conditions, though the Winter situation may be more critical for this than the Summer. Expect the media to catch up with this one soon.

[BLAST FROM THE PAST]

Odd isn't it, if you look at Unisys sst anomaly 'most' of the arctic is well below average!?

West looking at your graph what the heck is that blip around 1995/6, is that the RECORD minima? or a blip

BFTP

[West is Best]

Odd isn't it, if you look at Unisys sst anomaly 'most' of the arctic is well below average!?

West looking at your graph what the heck is that blip around 1995/6, is that the RECORD minima? or a blip

BFTP

I'm not sure Blast! I think it's the record.

Unisys doesn't really go as far as the arctic proper does it? The NOAA anomaly chart is very bleak in the arctic itself:

[parmenides3]

Odd isn't it, if you look at Unisys sst anomaly 'most' of the arctic is well below average!?

West looking at your graph what the heck is that blip around 1995/6, is that the RECORD minima? or a blip

BFTP

No: it's the greatest anomaly, which is dependent on the season: the blip shows that at some time in '95, ice levels were lewer relative to seasonal norms than at any other time. If that was't during the Summer, it wouldn't necessarily mean a minimum.

The record low by satellite measurement (extent-internal pooling) 'cover', was in 2002 (4.9 Million Km2). '03, '04 and '05 were almost as low, with '05 number 2 in the record book. The record low by traditional measurement, sea-ice extent, is NOW. This measure is still used because there is a record for c. 100 years; the sat. data starts in 1979. The last 4 years have seen 4 consecutive record lows in sea-ice extent.

I couldn't fit this on the edit button.

Courtesy of SOCC - the State of the Canadian Cryosphere:

Edited August 9, 2006 by parmenides3

[BLAST FROM THE PAST]

I'm not sure Blast! I think it's the record.

Unisys doesn't really go as far as the arctic proper does it? The NOAA anomaly chart is very bleak in the arctic itself:

West

Yes it has been commented on before hasn't it re the difference in the Unisys and NOAA, but for sure the ice is LOW.

Permanides3 thanks too

BFTP

[parmenides3]

Found a sat. image! Shows Chuckchi & Beaufort pools. Other pic. shows current analysis from IWICOS/IOMASA, from DMI.

Sorry, won't let me upload that other image.

Edited August 9, 2006 by parmenides3

[Stratos Ferric]

No: it's the greatest anomaly, which is dependent on the season: the blip shows that at some time in '95, ice levels were lewer relative to seasonal norms than at any other time. If that was't during the Summer, it wouldn't necessarily mean a minimum.

The record low by satellite measurement (extent-internal pooling) 'cover', was in 2002 (4.9 Million Km2). '03, '04 and '05 were almost as low, with '05 number 2 in the record book. The record low by traditional measurement, sea-ice extent, is NOW. This measure is still used because there is a record for c. 100 years; the sat. data starts in 1979. The last 4 years have seen 4 consecutive record lows in sea-ice extent.

I couldn't fit this on the edit button.

Courtesy of SOCC - the State of the Canadian Cryosphere:

B)

Cut that any way you will, it's a downward trend. Doubtless "Ice Age Now" will be claiming that the shape of the earth is changing so that, in fact, the ice is as extensive as it's ever been, it's just that the Arctic is getting smaller. Either that or they'll claim the plotter's jammed / not working accurately.

It's about time we started thinking about future habitats for Polar bears.

[BLAST FROM THE PAST]

Cut that any way you will, it's a downward trend. Doubtless "Ice Age Now" will be claiming that the shape of the earth is changing so that, in fact, the ice is as extensive as it's ever been, it's just that the Arctic is getting smaller. Either that or they'll claim the plotter's jammed / not working accurately.

It's about time we started thinking about future habitats for Polar bears.

SF

I don't think anyone was suggesting otherwise!? Plenty of zoos B)

BFTP

[parmenides3]

Looking more closely at the CT data, we might be jumping the gun a little, here. Their graphs show no ice at all in the Bering Sea - possible, and no graph at all for Okhotsk; I don't know why. The Kara Sea chart drops like a stone; unrealistically so. All three of the analysis graphics (MMAB, IWICOS and CT) show ice W. of Severnaya Zemlya, but the graph shows none. Suggests to me a data 'blip', which is not to say that the overall position is still not dire.

The ACIA report covers the Polar Bear situation (yes, I know you were being flippant).

B)

[BLAST FROM THE PAST]

Looking more closely at the CT data, we might be jumping the gun a little, here. Their graphs show no ice at all in the Bering Sea - possible, and no graph at all for Okhotsk; I don't know why. The Kara Sea chart drops like a stone; unrealistically so. All three of the analysis graphics (MMAB, IWICOS and CT) show ice W. of Severnaya Zemlya, but the graph shows none. Suggests to me a data 'blip', which is not to say that the overall position is still not dire.

The ACIA report covers the Polar Bear situation (yes, I know you were being flippant).

B)

There has been discussions in another thread re advanced ice melt because temps were as high in the arctic back in the 30s peaking in 1938 I believe as they are now but the ice coverage/extent was allegedly far greater. It would seem its not down to airtemps because the ice continued to reduce despite the cold period 40 to 70.

Interesting quote

You want radical change, radical warming? From 1920 to 1940, the Arctic temps skyrocketed, warming by +/- 4°C in two decades ... about twice as much as the current rise since 1960, and in less time, and all without the benefit of CO2 increase. If Greenpeace had been around then, they'd have had to blame it on ... heck, I don't know what they'd blame it on, but they'd be sure it's the fault of humans.

The question is not whether the world is warming. It is whether the warming is natural. I see nothing in the temperature graph of the recent Arctic warming that looks unnatural. From 1880 to 1940, the overall rise in Arctic temperature was steeper, larger, and longer than the current (1965-2004) rise.

To recap thus far, during the period of record 1880-present, Arctic temperatures generally:

Rose for 60 years, to 1940.

Fell for 25 years, to 1965.

Rose for 40 years, to the present.

Were higher in the 30's and 40's than they are today.

We know that the change in CO2 from 1880 to 1940 was far too small to be the cause of that first prolonged rise, so it must be a natural event. Thus we know for a fact that large, long-duration temperature increases in the Arctic occur naturally. In fact, there is nothing in the current record of Arctic temperatures that we haven't seen even in our pitifully short instrumental record. We've seen longer, warmer, and steeper in just the last century and a half.

BFTP

Edited August 9, 2006 by BLAST FROM THE PAST

[Thundery wintry showers]

At the moment, temperatures are if anything anomalously cool in the Arctic interior, so we shouldn't be getting too much melting at the pole. However, around the periphery of the ice sheet it is generally anomalously warm.

The Arctic warming between the 1920s and 1940s could be explained largely by anomalous synoptics, with the Arctic reverting to a positive phase, before swinging back negative afterwards. The same has been true in recent years, with the AO becoming even more strongly positive. A strong AO features depressions moving at high latitudes, keeping the coldest air stuck inside the very interior of the Arctic and bringing mild SW winds into Canada, N Europe and Siberia- that should sound familiar.

I actually think that until around 2002, much if not all of the warming could be explained synoptically- the Arctic interior and Greenland did not warm significantly until then (if anything they cooled a bit), and it was the peripheral areas that warmed. However, since then, we've seen a new trend, with depressions tracking even further north, and pumping tropical air right into the heart of the Arctic, giving temperature anomalies of 10-15C. The Arctic doesn't seem to have warmed much during summer (with the exception of the warm 2002), but the lack of winter cold means that the ice isn't getting to refreeze in sufficient amounts to survive the next summer's melting.

Some research suggests that tropospheric cooling (itself, in conjunction with a warmer surface, a sign of increased greenhouse gas concentrations) could be changing both the AO and NAO and contributing towards the anomalous synoptics we're seeing in winters at the moment, there's also the issue that warmer oceans, and reduced ice cover, may encourage more cyclogenesis at high latitudes, and can reduce albedo leading to accentuated warming.

Whatever, it appears that although much of the recent Arctic warming can be explained synoptically, there may be some anthropogenic input into these synoptics, together with the warmer global temperatures as a whole.

Edited August 9, 2006 by Thundery wintry showers

[BLAST FROM THE PAST]

TWS

A nicely laid out post with some explanations I fully concur with. As regards to albedo effect I'm not so sure about as that high up the sun has very limited strength...about 17% of what the tropics recieve.

regards

BFTP

[Thundery wintry showers]

Apologies for the editing and fumbling above- my internet decided to crash so I had to restart the computer.

[Damien]

Please post maps of the situation in 1969 and the situation now, plus some other (preferably more recent) years of both mild and colder winters when this wasn't the case, so we can compare.

[summer blizzard]

The development of a small cold anomoly to the west of the British Isles now favours a flat Jet Stream although most likely on the side of mild, there are two options which i am seeing and it all depends on the state of the PNA...

1) Positive PNA would encourge northerly flow with high pressure over Greenland

2) Negative PNA would encourgae a mild and unsetttled pattern

[parmenides3]

Teleconnections is favouring a negative PNA for the next 10 days or so, but the GFS isn't letting the the Eastern US systems anywhere near us, instead diverting them Northward. Doesn't this suggest that we'll be seeing some more warmth from the S/SW once the current LP clears?

P

[summer blizzard]

Due to the time lag, we will most likely not see the effects until the beggining of September.

[WhiteFox]

The development of a small cold anomoly to the west of the British Isles now favours a flat Jet Stream although most likely on the side of mild, there are two options which i am seeing and it all depends on the state of the PNA...

Unless I'm reading the map wrong, I see no cold anomaly to the West of the British Isles? It looks average to above average to me!

[summer blizzard]

It is just to the west of Ireland, it was bigger a few days ago.

[Stratos Ferric]

I note a report today on Ceefax today that scientists are writing in one of the forthcoming journals that the rate of melt in Greenland is increasing.

[BLAST FROM THE PAST]

I note a report today on Ceefax today that scientists are writing in one of the forthcoming journals that the rate of melt in Greenland is increasing.

SF

Yes it was brought up yesterday by Parmenides3, I think specifically in the very recent years as in this century. Even though the interiro has been 'cold' with increased precip the coastal retreat has increased. Ocean warming?

BFTP

[parmenides3]

SF

Yes it was brought up yesterday by Parmenides3, I think specifically in the very recent years as in this century. Even though the interiro has been 'cold' with increased precip the coastal retreat has increased. Ocean warming?

BFTP

Interestingly, (related to our other discussion, Blast), the press release that these reports are based on (from the University of Texas at Austin - click on 'news'), suggests as one idea that this could be the consequence of a weakening of the THC, leading to less cold water coming down the shallow Greenland Ice Shelf.

There's an interesting paper on this, from March 2006, on http://www.realclimate.org/index.php?p=267

(It's also worthwhile to read the blogs at the bottom)

The paper points out that three different recent papers have come up with three different estimates of ice mass balance from the same data; the latest is an update of these.

P