Arctic Sea Ice

ASI 2012 update 11: end or beginning?

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

September 22nd 2012

I left for a vacation after all the records had been broken and have returned just in time to see all the minimums get hit on the various graphs. In the past couple of years the National Snow and Ice Data Centre in Boulder, Colorado, has built up a well-deserved reputation of being the number one source of information when it comes to Arctic sea ice. When they called the minimum three days ago, it was picked up far and wide by news agencies around the world, an even better response than when all the records started to break one by one a little over a month ago.

I remember well the excitement I felt around this time in 2010 and 2011, checking all the graphs and satellite images every hour, trying to predict when the melting season would end. But none of that this year. Maybe it's because I still feel overworked, despite my vacation. Maybe it's because the records were broken so early in the season, preceded by several spectacular events. Maybe it's because this melting season was so freakish that it was practically impossible to pinpoint the minimum a few days in advance.

All those factors play a role, but what I think is going on, is that this stunning melting season has made me even more acutely aware of the gravity of what is taking place. This melting season has provided the final and definite confirmation that the ice is thin, PIOMAS has it largely right, and I have a very hard time finding indications that this is going to turn around real soon. To be able to watch and write about the Arctic sea ice, I used to block out the realisation of risks, so that I could make a joke here and there and be scientifically reticent in my own amateur way, keeping up appearances, acting objective.

But my bubble has burst. I'm already watching past the minimum. As the melting season ends, it feels as if things are only beginning. The age of consequences.

Sea ice extent (SIE)

Now that AMSR2 is operational, IJIS doesn't seem to revise the last data point, so I'm including it for this latest graph:

On September 16th the trend line shortly dipped below 3.5 million km2, reaching a minimum extent of 3.489.063 square kilometres. That's more than three quarters of a million below the 2007 record, and more than a million below 2011. I knew that there was a good chance the record would be broken this year, but never imagined it would be by such a large margin. Especially not with circumstances that in many ways were the opposite of those in 2007.

The current difference between 2012 and other years is as follows:

ASI 2012 update 10: (wh)at a loss

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

August 25th 2012

I apologize for having provided so little analysis lately, but things are moving so fast that analysis can't keep up. Now I know what an IPCC regional model for the Arctic must feel like. ;-)

Basically, I'm at a loss for words, and not just because my jaw has dropped and won't go back up as long as I'm looking at the graphs. I'm also at a loss - and I have already said it a couple of times this year - because I just don't know what to expect any longer. I had a very steep learning curve in the past two years. We all did. But it feels as if everything I've learned has become obsolete. As if you've learned to play the guitar a bit in two years' time, and then all of a sudden have to play a xylophone. Will trend lines go even lower, or will the remaining ice pack with its edges so close to the North Pole start to freeze up?

Basically I have nothing to offer right now except short posts when yet another of those record dominoes has fallen. Hopefully I can come up with some useful post-melting season analysis when I return from a two-week holiday.

I'm at a loss at this loss. The 2007 record that stunned everyone, gets shattered without 2007 weather conditions. The ice is thin. PIOMAS was/is right.

Sea ice extent (SIE)

WindSat or no WindSat, the 2012 trendline on the IJIS SIE graph has dropped like a rock:

I had to adjust the Y-axis on this graph already once (compared to the one in the last ASI update), and it looks like I'll have to adjust it again. I already announced the new IJIS SIE record minimum yesterday, although it was based on the preliminary number. But after the revision the record is still standing and IJIS still hasn't stopped producing century breaks.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows:

ASI 2012 update 9: stormy weather

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

ATTENTION: There are new polls in the right hand bar, closing August 20th.
One is for Cryosphere Today minimum daily sea ice area, the other for NSIDC minimum monthly sea ice extent (the one that is used for the SEARCH SIO projections). More info in this blog post.

August 11th 2012

Another two weeks have passed since the last ASI update, and my, what an exciting two weeks they have been. For me personally, the most exciting period since the inception of this blog. And perhaps the most disconcerting so far.
As I wrote two weeks ago:

For a fast decrease you need a strong high in the 1025-1035 hPa range, preferably over the Beaufort Sea. Or a nice cyclone in the 985-995 hPa range to stir things up and cause some of that flash melting that we love so much on the ASI blog because it looks so awesome.

What we got, was a huge cyclone in the 963 hPa range. If you've missed this mega-storm despite all the news stories in the mainstream media (yes, I'm being sarcastic), you can check out the Arctic storms category and see the day-to-day reports here on the ASI blog. Flash melting usually takes place from one sea ice concentration map to the next. This time it's days in a row and it still isn't over yet.

This highly unusual summer storm has massacred all that weak ice on the Pacific side and even caused a large swathe of ice floes to detach itself from the main ice pack. The Stronghold I wrote about a month ago is no more. Trend lines have dropped precipitously on every single sea ice extent and area graph out there.

What is important to remember, is the large discrepancies between this melting season and that of 2007. The latter had almost perfect weather conditions during almost the entire melting season, with lots of sunshine and compacting winds. 2012 had a reasonably good June, but after that the weather switched and hasn't switched back since. Those ideal weather conditions in 2007 pulled in large amounts of warm water through Bering Strait decimating the ice pack on the Pacific side of the Arctic. If 2012 is pulling anything through Bering Strait, it's cold water. The ideal weather conditions in 2007 pushed out very large amounts of multi-year ice through Fram and Nares Strait. 2012 doesn't come close to it. But still, even before the storm, 2012 was following the 2007 trend line as if the Arctic wasn't cloudy and winds weren't blowing the wrong way.

The fact that 2012 followed 2007 so closely, was the strongest evidence possible that a large part of the ice pack is so thin that it will melt out no matter what the weather conditions. The storm only emphasized this, giving all that thin ice a push into the abyss.

Keep that in mind when you see fake skeptics use this storm to mislead their audience into thinking that the storm, a freakish fluke, is the cause of however this melting season is going to end. Although I think they're going to keep quiet about the Arctic, like they are doing most of the time now. As if the Arctic isn't part of our planet. A part of paramount importance.

Sea ice extent

Ever since the switch from the defunct AMSR-E to WindSat the IJIS SIE graph is acting different than all the other graphs (see this blog post), but the storm has finally pushed the 2012 trend line in first position here as well:

The 2012 trend line is now below all the others, even 2007, for the first time since the start of the melting season. It noted 6 century breaks in the last 8 days, and it's not entirely sure whether it will stop there. We're looking at a very exciting end to the melting season with this graph.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows:

ASI 2012 update 8: it shouldn't, but it does

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

ATTENTION: There are still 3 days left to vote on the polls in the right hand bar.
One is for Cryosphere Today minimum daily sea ice area, the other for NSIDC minimum monthly sea ice extent (the one that is used for the SEARCH SIO projections). More info in this blog post.

July 28th 2012

I'm basically going to say the same thing as I did in the last ASI update: Weather patterns haven't been conducive to sea ice decrease, trend lines on graphs should be stalling, but they don't. As I've shown in yesterday's blog post comparing this year's weather patterns in June and July with previous record years, the decrease should have slowed down significantly like it did in 2010 and 2011, but it didn't. The 2012 SIE trend line shouldn't follow 2007 so closely, but it does. The 2012 SIA trend line shouldn't lead, but it does.

Now air and sea surface temperatures are higher than in previous years, but does that explain all of it? Personally, I don't think so. I think ice thickness is playing a big part in all of this. One of the conclusions I found most important last year, was that, yes, the weather is still dominant and determines whether a melting season will see a new minimum record or not, but only as much as ice thickness will allow it. There comes a point when large parts of the ice pack become so thin that it doesn't matter what the weather does. Sure, ideal conditions will cause a nosedive, but the train keeps chugging along, even when the weather isn't so great for melt, transport and compaction.

I believed I saw that in September 2011. I believe I'm seeing it now too,
4-6 weeks earlier. Maybe my eyes deceive me.

Sea Ice Extent (SIE)

In the last ASI update I was wondering whether the 2012 trend line
on the IJIS SIE graph would veer off to the right towards big staller 2010:

But it didn't. Especially in the last couple of days the 2012 trend line has decided to track new leader 2007, after following 2011, which had a brake put on its decline in mid-July. 2007 had a very strong first week in August, so it will be interesting to see whether 2012 can keep up or not.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows:

ASI 2012 update 7: steady as she goes

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

* There are still two weeks left to vote on the polls in the right hand bar.
One is for Cryosphere Today minimum daily sea ice area, the other for NSIDC minimum monthly sea ice extent (the one that is used for the SEARCH SIO projections). More info in this blog post.

July 15th 2012

Two weeks have passed since the last ASI update. At the time the weather forecast for the Arctic showed things that pointed to a (possibly big) nosedive on sea ice extent and area charts. The forecast became even worse, showing a very big, very strong high-pressure area over the Beaufort Sea and low- pressure systems on the Siberian side of the Arctic. In other words, a hefty Dipole Anomaly, that we saw so much of in 2007.

But none of it came about. The weather forecast completely changed its tune and instead was showing a low-pressure area taking over things. Which did come about. So the nosedive didn't really live up to its weather forecast potential, and I was expecting a lull, a stalling, a levelling off of trends on graphs, but this hasn't really come about either! In the end nothing much has changed when it comes to the graphs in the past two weeks.

If the weather forecast had come about, 2012 would have undoubtedly taken a big lead, but as we say in Dutch: If my aunt had had a dick, she'd be my uncle! Instead, 2012 keeps steadily ploughing towards the minimum (two months from now), still battling it out with the big boys, apparently not much perturbed by atmospheric patterns that brought a stop to the 2010 and 2011 marches for melting season glory. Although that stop could still be coming about in the next week.

I hope I can shed some light on the how, why, and whence from here, but sometimes I feel as if all I've learned in the past two years has already turned obsolete.

Sea Ice Extent (SIE)

Right when I expected the lull to start showing up on the graphs, IJIS decided to go for a string of century breaks that kept it in the wake of 2011:

We can clearly see how 2010 levelled off when the weather switched at the beginning of the month. The same thing happened to 2011 when the weather switched halfway through the month. And maybe we are seeing the start of a similar situation for this year, now that the string of century breaks has been followed by two daily decreases of just 58 and 57K km2.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows:

ASI 2012 update 6: piggy bank

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

July 1st 2012

The ASI update from two weeks ago ended with a couple of questions:

Will the conditions that were so conducive to melting have an inertia-like effect on the SIE and SIA numbers? And what is that big low going to do? Will it tear up the ice pack so we get to see the holes we did in the 2010 melting season? And how about those highs over the Siberian coast during Summer Solstice?

As expected the speedy decrease slowed down considerably, but enough was going on all around the Arctic for the 2012 SIE and SIA trend lines to stay close to the bottom years. That big low-pressure system definitely left a mark all over the Arctic, see for instance the holes in the ice pack on this satellite image for June 26th. It is very reminiscent of 2010, but earlier this time around. And those highs over the Siberian coast? I think they had something to do with SST anomaly charts needing extra colours.

On the day the last ASI update came out, LiveScience had an article about this year's potential new record, with a couple of quotes from the NSIDC's Dr Walt Meier (also known as Saint Walt because of his missionary work in certain corners of the blogosphere):

The tilt of the Earth's axis means the sun does not set above the Arctic Circle on the summer solstice, with summer days growing longer even farther north. As a result, the more dark water exposed to sunlight around this time, the more heat it can soak up.

"In a way it is almost like building up a bank account of heat," Meier said.

Everything is pointing towards a lot of savings in this respect, and interest will probably be high too. But 2012 also has a little piggy bank of melting potential that the other years with low SIE and SIA did not have. While melting very rapidly on the Atlantic side of the Arctic, 2012 decrease is still relatively slow in easy ice places like Hudson Bay and the Greenland Sea. If the weather allows 2012 to break that little piggy bank we will witness another radical nosedive.

All of this and more in ASI update 6.

ASI 2012 update 5: when graphs agree

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest.

Check out the Arctic Sea Ice Graphs website
for daily updated graphs, maps and live webcam images.

* There are still two weeks left to vote on the polls in the right hand bar.
One is for Cryosphere Today minimum daily sea ice area, the other for NSIDC minimum monthly sea ice extent (the one that is used for the SEARCH SIO projections). More info in this blog post.

June 15th 2012

When even odd man out Arctic ROOS - popular in certain quarters during certain seasons - says that 2012 currently has the lowest sea ice extent and area, then you know we're talking business. Since the last ASI update things started out slow at first, but then trend lines dropped off a cliff, on some graphs even approaching vertical conditions, century breaks everywhere you look. Practically all graphs are in agreement, except for one.

So what is causing the Arctic to scream extra loud (just in case somebody out there is still not hearing it)? There are two obvious reasons. First of all, the easy ice is going. All that extra ice that gave rise to the late and relatively high maximum, was wafer-thin. The second reason is that prolonged clear skies, especially over the Beaufort Sea, has caused a lot of melt ponds to form. These cause satellite sensors to see open water where there actually is none.

This 'goodbye, easy ice, hello, melt ponds' theory explains a lot, but I don't think it tells the whole story. There are other factors as well. Either way, it's one hell of a start to the melting season. But will it last?

Sea Ice Extent (SIE)

So if even the Arctic ROOS graphs indicate that 2012 has the smallest ice cover for this time of year, which graph could possibly be disagreeing? Why, it's our beloved IJIS SIE graph that hasn't quite come around yet:

It's getting there, but it still has 2012 in third position. Maybe this is because of the switch from AMSR-E to WindSat, I don't know, and it doesn't really matter either in this phase of the melting season. Nevertheless, 2012 had the highest daily SIE decrease for the last 9 days, a series including 6 century breaks.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows:

ASI 2012 update 4: converging and diverging

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.

June 2nd 2012

It's that time of the year when trend lines on area and extent graphs huddle up for a short while, before entering the period of rapid melt and going their separate ways. Since the last ASI update the 2012 trend line has started to assert itself, albeit more on the CT SIA graph than the IJIS extent graph. The reason for this could be melt ponds, as much of the Arctic is coming out of the recent cold(ish) spell and insolation is on the rise. Or it could have to do with divergence of the ice pack. Or both. And of course, with IJIS switching from AMSR-2 to WindSat some of the changes (bigger resolution, for instance) might influence the SIE decrease, making it differ from previous years, so let's just keep observing the observations and see how that goes.

Sea Ice Extent (SIE)

I've decided to stick with the way I'm making these monthly graphs, because they show more detail than graphs that show the whole year. On this IJIS SIE graph for May we clearly see the trend lines converging (on the June graph I'll post in the next ASI update you'll see them diverge again). In the last two weeks 2012 has moved to the upper part of the pack of trend lines, for the full thing go to IJIS:

I don't use the last data point because it's unrealistically low before revision, but including June 1st, the current difference between 2012 and the other years is as follows:

ASI 2012 update 3: international daily data day

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.

May 21st 2012

Be careful what you wish for, because you just might get it, as the saying goes.

After complaining that everything was going to pieces for us avid Arctic watchers, with malfunctioning sensors, satellites and servers, suddenly out of the blue a cascade of data came online. First the NSIDC with thickness data from the NASA IceBridge Mission (check out the excellent graph in this blog post), followed by a resumption of IJIS sea ice extent data, and Cryosphere Today sea ice area came back online not long after that. To top it all off, JAXA announced that the satellite that carries the AMSR-2 sensor was succesfully launched and brought into orbit. So from now on May 15th will be known as International Daily Data Day on this blog. I guess that now I will have to give IJIS SIE and CT SIA equal space in these ASI updates. A double amount of work, but hey, I asked for it!

And what's going on with the ice, you may ask. Well, nothing that wasn't expected. There was a slight negative temperature anomaly over the Arctic, but the 2012 trend line has nevertheless come down from its lofty abode and seems to be ready for another clash of the trend lines.

Sea Ice Extent (SIE)

IJIS has altered its graph and instead of some of the most recent years is now showing averages for the 80's, 90's and 2000's (edit: the 'old style plot' is here). This is of course fine, but I like to compare this year with the other years in the 2005-2011 period, so I've decided to make my own graphs (still fiddling around though, so these might change). Here's the IJIS SIE graph for May, for the full thing go to IJIS:

I have left off the last data point, because it goes very low every day (around 200K), but is revised just as much upwards the next day. So this graphs runs up to May 20th.

The current difference between 2012 and the other years is as follows:

ASI 2012 update 2: no daily data

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Because of the demise of AMSR-E the IJIS sea ice extent (SIE) numbers are no longer central to these updates. Instead I now use Cryosphere Today sea ice area (SIA) numbers and compare them to the SIA numbers in the 2005-2011 period. NSIDC has a good explanation of sea ice extent and area in their FAQ. I also look at other things like regional sea ice area, sea ice extent, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.

May 13th 2012

How depressing (image courtesy of Terrible Taxidermy). First we lost the great day-to-day extent data provided by IJIS. A couple of weeks ago ENVISAT stopped transmitting data, which means we no longer have these great radar images to check out the ice plug in Nares Strait. And since April 28th the good people over at the University of Illinois at Urbana-Champaign are having some server problems, which means their excellent Cryosphere Today page hasn't been updated since. So no daily sea ice area data either.

Apart from Larry Hamilton keeping us up-to-date every couple of days on the DMI SIE numbers, and Dr.Tskoul keeping an eye on MASIE numbers, there is nothing there to satisfy my curiosity and obsession with Arctic sea ice. And the basis on which these ASI updates are written is swept right from under my feet...

But let's stay positive, okay! At least it isn't September! And as long as we have eyes to see, we can still gaze at various graphs. So that's exactly what we're going to do in this ASI update.

The NSIDC SIE chart had SIE dropping fast, but it has leveled off again in the past week or so: