Arctic Sea Ice

Will Petermann calve another one this summer?

Here's a blog post I just read on Andreas Muenchow's Icy Seas blog:

Is Petermann Gletscher Breaking Apart this Summer?

I am disturbed by new ocean data from Greenland every morning before breakfast these days. In 2015 we built a station that probes the ocean below Petermann Gletscher every hour. Data travels from the deep ocean via copper cables to the glacier surface, passes through a weather station, jumps the first satellite overhead, hops from satellite to satellite, falls back to earth hitting an antenna in my garden, and fills an old computer.

A 7-minute Washington Post video describes a helicopter repair mission of the Petermann data machine. The Post also reported first result that deep ocean waters under the glacier are heating up.

Sketch of Petermann Gletscher’s ice shelf with ocean sensor stations. The central station supports five cabled sensors that are reporting hourly ocean temperatures once every day. Graphics made by Dani Johnson and Laris Karklis for the Washington Post.

After two years I am stunned that the fancy technology still works, but the new data I received the last 3 weeks does worry me. The graph below compares ocean temperatures from May-24 through June-16 in 2017 (red) and 2016 (black). Ignore the salinity measurements in the top panel, they just tell me that the sensors are working extremely well:

The red temperature line in the bottom panel is always above the black line. The 2017 temperatures indicate waters that are warmer in 2017 than in 2016. We observed such warming for the last 15 years, but the year to year warming now exceeds the year to year warming that we observed 10 years ago. This worries me, but three features suggest a new ice island to form soon:

Read the rest here.

Lakes on a glacier

Reading the latest NSIDC Greenland melt analysis, I came across this short video at the bottom of the summary. It's about melt lakes on top of the western part of the Greenland Ice Sheet and has nice visuals (you can spot Jakobshavn) and a great voice-over. If you haven't seen it yet, here's your chance:

 

Jakobshavn record retreat

What a coincidence. Yesterday I wrote in a comment:

There's a fantastic segment on the Arctic Sea Ice Forum for discussing Greenland and its glaciers, with people presenting all kinds of analysis and satellite images. Really top quality stuff.

Well, the folks there (forum member Espen Olsen to be precise) have spotted a large change in Jakobshavn Isbræ, Greenland's fastest glacier draining 6.5 % of the Greenland ice sheet, between August 14th and 16th:

Espen reckons this is one of the largest calvings in many years, if not the largest. It also means that last year's retreat line has been passed now (date should be Aug 16 2015):

Shock news!

There is no shocking news, really. I'm just emulating a way of news reporting as seen in recent months by folks trying to play down the long-term shocking news of Arctic sea ice loss. You know, paid climate science disinformers like Benny Peiser who claimed that the poles aren't melting, twisting the words and work of a respected oceanographer and putting up a bunch of strawmen along the way, because global sea ice area is at a record high.

It's a neat trick, even though it's like saying that one billion people starving globally is not a problem, because there are one billion obese persons. We all know that Antarctic sea ice has been increasing in winter, most likely because of winds that push the ice further out, with the open water left behind freezing up again. So if you compare Antarctic winter anomalies with those of Arctic summer anomalies - especially during rebound years such as 2013 and 2014 - it looks as if not much is happening.

However, if you compare the numbers as they are, during the same season, the picture is, well, shocking:

That graph (found here, updated at the end of this blog post) shows the minimum in both Arctic and Antarctic, which never occur at the same time, of course. In the end it's all about the minimum and the period leading to it, because that's the time when most of the sunlight reaches either one of the poles. And there is hardly a trend in the Antarctic minimum, despite the spectacular winter increases, because most of it melts out anyway in summer. As can be seen on the small image at the top of this blog post, showing that the only Antarctic place with a substantial amount of sea ice left right now, is the Weddell Sea.

And it's like that every year, contrary to the entirely different Arctic. Not everyone knows this, and so this is what climate science disinformers use to fool people and thus delay meaningful climate mitigation policies that threaten either their wallets or their beliefs, and most of the time both.

Jakobshavn calves a(nother) big one

Greenland glacier guardian Espen Olsen informed us a couple of days ago on the Forum that Jakobshavn Isbræ - Greenland's fastest glacier draining 6.5 % of the Greenland ice sheet - has had another big bite taken out of its southern branch recently. Espen made this animation to show the difference between May 7th and June 1st (red circle added by me):

Estimates by Espen and other commenters vary from 5 to 10 km2 of ice lost (a couple of hundred times thicker than sea ice). Reading back the first blog post on Jakobshavn, not long after starting the blog back in 2010, it seems that this number is big enough to warrant some media attention. As NASA had it back then:

NASA-funded researchers monitoring Greenland's Jakobshavn Isbrae glacier report that a 7 square kilometer (2.7 square mile) section of the glacier broke up on July 6 and 7, as shown in the image above. The calving front – where the ice sheet meets the ocean – retreated nearly 1.5 kilometers (a mile) in one day and is now further inland than at any time previously observed. The chunk of lost ice is roughly one-eighth the size of Manhattan Island, New York.

Or maybe these things don't get noticed anymore as it has become 'normal'? Let's hope not.

Building a 30 year glacier mass balance time series

Here's a short blog post from some other part of the cryosphere, dedicated to the hard work that scientists are putting into gathering data. These are not think tank folks in suits devising strategies for steering public opinion or keeping it in place. These are hard-working people who go out there to assess situations, make measurements, build up collections of data. Even though we rarely hear about them, there are thousands of honest people doing this, tens of thousands, now, yesterday, tomorrow.

From glaciologist Mauri Pelto's blog From a Glacier's Perspective:

 

The above video looks at the effort behind a long term field study, looking at images from 11 of the 30 years of our research. Long term monitoring programs have until recently been unattractive for federal grantmakers, since they are not directly advancing the frontiers of science. However, many long duration time series from monitoring programs do advance science eventually as the response to changes in environmental or climate conditions are documented. In 1984, I responded to a request from the US National Academy of Sciences, “to monitor glaciers across an ice clad mountain range”, something that was not being done anywhere in Norther America. Thirty years later we are still pursuing this project. We have developed a 30 years time series of glacier mass balance on glaciers across the North Cascades of Washington. To ensure that the program could be sustained, we did not pursue any federal funding for the project. The data we, collect is submitted to the World Glacier Monitoring Service (WGMS) each year, the regional time series built in the North Cascade is just part of the contribution to the global glacier mass balance time series at WGMS. The cumulative North Cascades glacier mass balance record is in fact quite similar to the cumulative global mass balance time series. For the globe there have been 22 consecutive years of negative mass balance, that is the reality of the impact of global warming on mountain glaciers around the globe. The impact on the glaciers of Mount Baker was recently published: Pelto and Brown (2012).

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Peter Sinclair also has a new video out for the Yale Forum on Climate Change & the Media, with more of those hard-working people discussing the implications of Greenland and Antarctic ice sheet instability for sea level rise:

Freezing season 2013/2014 open thread 2

First open thread reached the 200 comment mark, so it's time for a new one.

Over on the Arctic Sea Ice Forum commenter Espen keeps track of several things related to sea ice and the Greenland Ice Sheet, one of those being the Jakobshavn Glacier - also known as Jakobshavn Isbræ and Sermeq Kujalleq - which I wrote about a bit back in 2010, in 2011 and last year.

It looks like Jakobshavn has retreated another 3 km inland, despite a cold melting season for Greenland:

This time it was the southern branch that retreated most. As NASA's Earth Observatory had it, also back in 2010:

In the winter of 2010, Jakobshavn’s ice front did not re-advance as it usually does, so it began the 2010 melt season in the same location as the 2009 summer melt season. As a result, the glacier had the potential to experience significant retreat during the summer of 2010. The breakup in early July 2010 occurred on the northern tributary to Jakobshavn Glacier. The southern tributary actually drains a larger portion of Greenland’s central ice sheet, so a retreat there could lead to a more substantial ice discharge.

Thank you, Espen!

ASI 2013 update 3: the Arctic goes POP

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 Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2012 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 of particular interest.

The animation on the right consists of NSIDC
sea ice concentration maps, one for each ASI update.

Check out the Arctic Sea Ice Graphs website (ASIG)
for daily updated graphs, maps, live webcam images and
the Arctic Sea Ice Forum (ASIF) for detailed discussions.

June 21st 2013

Happy June Solstice!

With the fading of the persistent cyclone (PAC-2013) that held the Arctic in its grip for several weeks, the slow start of the melting is now definitely behind us. The cold has almost dissipated and massive heat waves in Alaska and Siberia spell trouble for the ice that is still clinging to respective coasts. The melting is shifting gears as we speak.

But 2013 is still trailing most of the other years, and especially 2012 that put on quite a show last year around this time. Whether 2013 can make up the deficit in weeks to come, depends as always on the weather, but also on the postponed effects PAC-2013 might have had on the ice pack, especially in its centre. There are large zones that look particularly weak, full of small ice floes, but it's not entirely sure what will happen, and more importantly, when it will happen.

Sea ice area (SIA)

The 2013 trend line (based on Cryosphere Today sea ice area data) was about to reach a cluster of years following a series of five century breaks in a row, but an uptick reported today threw a spanner in the works.

Here's the graph based on the latest data:

Dark Snow Project

I've waited with this blog post to kick off a second round of donations for this worthy project, aimed at measuring the impact of changing wildfire and industrial soot levels on snow and ice reflectivity.

Because of a lack of government funding Dr. Jason Box from the Byrd Polar Research Center (here's his blog) is now trying to raise through crowdfunding the money that is needed to fly to the top of the Greenland ice sheet and take samples. This data is very useful, as the reflectivity of the Greenland ice sheet has been decreasing steadily for a while now. The effects of this decrease have been documented here and elsewhere around the web last summer, when practically all of the surface of the ice sheet was melting at some point, a rare occurance.

Lower reflectivity of course means more melting, so reducing soot emissions might be a great help in slowing down the current melting trend of the Greenland ice sheet (and perhaps some of the Arctic sea ice melt as well), but for that we need to know how big a role soot is playing in all of this.

This video from Peter Sinclair's blog explains it all
(please watch if you haven't already):

You can donate at the Dark Snow Project website.

Another project that Dr. Box is involved in, is called Extreme Ice Survey, and that's the organisation that delivered the footage that was used for the popular Chasing Ice documentary:

More from Greenland

Greenland's glaciers and ice sheet have become an integral part of this blog. Perhaps it should be renamed to ASIGIS blog? ;-)

This clip from the Chasing Ice documentary has been doing the rounds lately. It's showing the largest iceberg calving ever filmed, with 7.4 cubic km of ice crashing off Jakobshavn Isbræ:

I'm guessing the calving took place in June of this year, basing myself on this CAD image that commenter Werther had made at the time (and I used in the Dark side of Greenland blog post). It shows the glacier's retreat since 2011, with the 2012 June event in red:

Back then I wrote:

Those are pretty big calvings, but strangely enough, I haven't seen any reports anywhere (of course, the Cruise-Holmes divorce must take precedence).

Better late than ever, eh? Especially when it's accompanied by awesome footage.

[edit: commenter Perwilainen has very convincingly explained that the footage is from 2009. Keep those cameras rolling if you want to film an even bigger calving event]

Speaking of Werther.. He made another CAD image, a very detailed one using the LANCE-MODIS satellite images of the Arctic, showing the boundary of the ice sheet (click for a very large version):