Arctic Sea Ice

If only I were smart...

It seems that a bunch of data from the NASA IceBridge Mission has been put online by NSIDC:

IceBridge Sea Ice Freeboard, Snow Depth, and Thickness Quick Look

The NASA IceBridge Sea Ice Freeboard, Snow Depth, and Thickness Quick Look data set is an evaluation product containing derived geophysical data products retrieved over the Arctic sea ice cover from 14 March to 02 April 2012 using the IceBridge Airborne Topographic Mapper (ATM), Snow Radar, Digital Mapping System (DMS), and KT19 pyrometer. This quick look product is experimental and is designed to be applicable for time-sensitive projects such as sea ice forecasting. The data were collected as part of Operation IceBridge funded campaigns, are stored in ASCII text files, and are available via FTP.

Access the IceBridge Sea Ice Freeboard, Snow Depth, and Thickness Quick Look product.

Feedback on this product can be submitted to nsidc@nsidc.org.

This could be another clue that tells us something about the thickness of the ice and what we might expect could happen this melting season. Unfortunately, I totally lack the skills and knowledge to work with these files (even if they are .txt files that I actually know how to open), but maybe some of the commenters find it interesting enough to take some time to make sense of the files?

UPDATE:

Commenter deconstruct has visualized the IceBridge flight data onto a NSIDC Polar Stereographic Grid (read more on it in his comment below):

PIOMAS May 2012

Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:

This year's trend line dipped below last year's only to go up again in the first two weeks of April, probably reflecting the late ice growth we saw here and there on the fringes of the ice pack, that also had trend lines on extent and area graphs flirting with the long-term average for a while. Very similar to 2010, but with thinner ice according to PIOMAS.

Here is Wipneus' graph for which he calculated the "expected" 2012 values, based on the same date values of 1979-2011 and an exponential trend. A caveat from Wipneus: "Note that the (not indicated) statistical error bars are quite large."Because there haven't been any updated CT SIA numbers I cannot update the average thickness map (PICT) I first posted last month. I'll update this post as soon as the sea ice area data comes online.

For the time being I'm posting the PIOMAS anomaly graph:

2011/2012 Winter Analysis

I'm starting this blog post off with a conclusion that was reached a while back already: sea ice on the Atlantic side of the Arctic looks vulnerable, sea ice on the Pacific side should be thicker.

Right, with that out of the way we can now look at various aspects of the 2011/2012 freezing season, and compare them to previous years, to be precise the previous freezing season of 2010/2011, and the freezing seasons leading up to and following that other record year: 2006/2007 and 2007/2008. Simply put: I'll be comparing 2007, 2008, 2011 and 2012 before their respective start of the melting season.

I'll try not to use too many words, but I'll be using a lot of images. Click on them images if you want a bigger version.

Ice age

I'll start with the AARI ice age maps. These images are for the end of April, and they look upside down, because it's from the perspective of the Russians who produced them:

Live blog: CryoSat results

This was the live coverage of the whole event. Please discuss below.

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Refresh this page manually (F5)

On the ESA homepage it says:

Watch online: CryoSat results

Live from the Royal Society in London, watch the unveiling of the first map of the winter 2010–11 changes in Arctic sea-ice thickness measured by ESA’s CryoSat satellite. Join the event via live web stream Tuesday starting at 07:30 GMT (09:30 CEST – 08:30 UK time).

9.31: I have just managed to connect and am waiting for the broadcast to start.

9.32: Broadcast has started.

9.35: This is the audience:

9.37: It has started. David Williams from the UK Space Agency is doing a short introduction. Followed by David Willets, Minister of University and Education. Lauds the UK Space Agency, lauds Great Britain. :-)

9.45: It's Volker Liebig's turn, director of Earth Observation Programmes from ESA. Congratulates UK Space Agency with 50 year anniversary. Jumps to Arctic Sea Ice immediately, shows consecutive extent records. Shows Stroeve's graph of trend deviation from IPCC models. Arctic important for climate change, but also geopolitically and for shipping.

PIOMAS April 2012

Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:

Still on a par with last year.

Wipneus produces many excellent PIOMAS graphs. I'll start with his latest creation, the graph for which he calculated the "expected" 2012 values, based on the same date values of 1979-2011 and an exponential trend. A caveat from Wipneus: "Note that the (not indicated) statistical error bars are quite large."

As a bonus I have finally come round to making a new graph, one that very crudely shows average ice thickness across the Arctic, by simply dividing the PIOMAS volume numbers (km3) by the Cryosphere Today area numbers (km2), and multiplying them by 1000 to get the average thickness in meters:

PIOMAS March 2012

The Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center has been updated:

Slightly lower than last year...

Wipneus has produced a new graph for which he calculated the "expected" 2012 values, based on the same date values of 1979-2011 and an exponential trend. A caveat from Wipneus: "Note that the (not indicated) statistical error bars are quite large."To top it off, here's the PSC graph with the anomaly from the downward trend:

A new way of measuring ice thickness

We have a pretty accurate 2D view of the Arctic sea ice, and some clues with regards to its third dimension: thickness. It's the thickness of the ice that determines the influence of atmospheric conditions on the ice pack, and is thus a crucial factor in the amount of sea ice that covers the Arctic Ocean during any given time, especially towards the end of the melting season. But also during the freezing season sea ice thickness plays an important role as an intermediary between sea surface and atmosphere. The thinner the ice is, the more heat and moisture can be transferred from one to the other, which in turn influences atmospheric patterns.

image on the top right, courtesy of NSIDC

The importance of accurate sea ice thickness measurements is not lost on the scientific community. We've had ICESat, we eagerly await the end of the calibration phase of the CryoSat-2 mission, and in the meantime another handy tool for measuring ice thickness has been devised by scientists from the University of Hamburg, using a passive microwave sensor aboard the ESA's Soil Moisture and Ocean Salinity (SMOS) satellite.

images retrieved from the SMOSIce wiki (with permission of L. Kaleschke)

The news was announced two months ago in an ESA press release, but has now been followed up by a research paper that has just been accepted for publication in Geophysical Research Letters: Kaleschke, L., X. Tian-Kunze, N. Maaß, M. Mäkynen, and M. Drusch (2012), Sea ice thickness retrieval from SMOS brightness temperatures during the Arctic freeze-up period.

From the abstract:

February 2012 Open Thread

There's a poll in the right hand bar running until February 8th for predicting the Cryosphere Today maximum sea ice area number. Don't be afraid to share your prediction in the comments of this thread: 2012 Maximum Area Pool

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We are entering the final phase of the freezing season. After that there will be a short lull, with sunlight and warmth trying to grab the Arctic back from Winter's clutch. Then the melting season will start all over again.

Image retrieved from this blog post on ringed seals

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Edit February 4th: the scientists at the University of Washington's Polar Science Center have updated the PIOMAS volume graph:

Storm impacts

The 'Arctic Hurricane' that slammed into Alaska and Siberia a couple of days ago caused wide- spread damage and presumably cost one person his life. Luckily the storm didn't top the 1974 record storm, but still. As the Associated Press reported: Emergency responders called the storm an epic event that displaced residents, flooded the shoreline, ripped up roofs and knocked out power in many villages.

Jeff Masters from Weather Underground has more details:

The most powerful storm to affect the Bering Sea coast of Alaska since 1974 is slowly winding down today, after pounding Alaska's west coast and Eastern Siberia with hurricane-force winds, a destructive storm surge more than 8 feet high, waves up to 40 feet high, and heavy snow. The highest wind gust recorded during the storm, 89 mph, was at Wales at the western tip of the Seward Peninsula, which forms the U.S. side of the Bering Strait.

A storm surge of 8.6 feet hit Nome, Alaska near 9 pm EST last night, pushed inland by sustained winds that reached 45 mph, gusting to 61 mph. Large waves on top of the surge encrusted with sea ice battered the coast, causing extensive damage and coastal flooding. Significant wave heights at the Bering Sea buoy north of the Aleutian Islands reached 40 feet during the peak of the storm. The last time Nome, Alaska saw a storm this strong was November 11 - 12 1974, when the city experienced sustained winds of 46 mph with gusts to 69 mph, a pressure that bottomed out at 969 mb, and a storm surge of 13 feet. The center of yesterday's storm moved ashore over eastern Siberia near 12 UTC with a central pressure of 945 mb, and later bottomed out with a pressure of 943 mb. The storm's central pressure had risen to 958 mb this morning, with the center of the storm now located north of Siberia over the Arctic.

I'm sure we'll hear what the erosional effects on the coasts have been, but right now I'm primarily interested in the effects on the sea ice. It appears they were quite substantial. I've made an animation of sea ice concentration maps from Uni Bremen (who have switched from the defunct AMSR-E sensor to the SSMIS instrument aboard the DMSP satellites) from the past week:

PIOMAS September 2011 (volume record lower still)

The PIOMAS graphs at the Polar Science Center of the Applied Physics Laboratory at the University of Washington have been updated. It reached an all-time low of 4.4 thousand km3 last month, but went down some more as we can see on Larry Hamilton's stack graph (Larry also wrote a great blog post discussing these numbers):

So the new record minimum volume is 4.0 thousand cubic kilometers.

Here is the current volume as modeled by the folks from the APL/PSC:

And the volume anomaly:

Let me stress that these volume numbers aren't observed data, but are calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS, Zhang and Rothrock, 2003). The real numbers probably aren't off by much, and I base this on some snippets of information like the ice thickness measured at the North Pole by the Polarstern crew and buoy information, but we can't know for sure until the CryoSat-2 team starts churning out some well-calibrated numbers and ice thickness maps.

Commenter graphs

As always Wipneus was faster than the speed of light (or neutrinos if you prefer) and updated his graphs. Here is his graph showing all the yearly trend lines in the period 2002-2011: