Shock News – Massive Calving of Jakobshavn Isbræ

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We reported on similar “Shock News” back in February 2015, and now it’s happened again.

Here is a large animation of recent events at the Jakobshavn Glacier calving front, courtesy of Espen Olsen at the Arctic Sea Ice Forum.

Click to view the ~5 Mb file at full resolution:

[Edit – May 6th]

In the absence of further input from the somewhat “skeptical” commenter below, here is an extract from one of the “~1420 recent academic articles” referred to. Namely “Bed elevation of Jakobshavn Isbrae, West Greenland, from high-resolution airborne gravity and other data: Bed topography of Jakobshavn Glacier” by Lu An, Eric Rignot et al.:

Jakobshavn Isbræ, West Greenland, which holds a 0.6 m sea level volume equivalent, has been speeding up and retreating since the late 1990s. Interpretation of its retreat has been hindered by difficulties in measuring its ice thickness with airborne radar depth sounders. Here we employ high-resolution, helicopter-borne gravity data from 2012 to reconstruct its bed elevation within 50 km of the ocean margin using a three-dimensional inversion constrained by fjord bathymetry data offshore and a mass conservation algorithm inland.

We find the glacier trough to be asymmetric and several 100 m deeper than estimated previously in the lower part. From 1996 to 2016, the grounding line migrated at 0.6 km/yr from 700 m to 1100 m depth. Upstream, the bed drops to 1600 m over 10 km then slowly climbs to 1200 m depth in 40 km.

Jakobshavn Isbræ will continue to retreat along a retrograde slope for decades to come.

Watch this space!

Month in Review – Arctic Science Edition

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Inspired by my recent visits to Judith Curry’s blog this post will bring you links to the latest learned journal articles about Arctic sea ice. Together with occasional excursions into older and wider Arctic papers.

Judith’s “Week in Review” articles seem to last for a month, so this one will probably last for at least a year!

First up is an article apparently written by a regular reader of this humble web site! A University of Alaska article at phys.org begins:

In August 2016 a massive storm on par with a Category 2 hurricane churned in the Arctic Ocean. The cyclone led to the third-lowest sea ice extent ever recorded. But what made the Great Arctic Cyclone of 2016 particularly appealing to scientists was the proximity of the Korean icebreaker Araon.

For the first time ever, scientists were able to see exactly what happens to the ocean and sea ice when a cyclone hits. University of Alaska Fairbanks researchers and their international colleagues recently published a new study showing that sea ice declined 5.7 times faster than normal during the storm. They were also able to prove that the rapid decline was driven by cyclone-triggered processes within the ocean.

Note that it didn’t take us 5 years to write about the cyclone in question. Our article catchily entitled “The Great Arctic Cyclone of 2016” was published on August 13th 2016:

A storm is brewing in the Arctic. A big one! The crew of the yacht Northabout are currently sailing along the western shore of the Laptev Sea and reported earlier today that “The sea is calm. Tomorrow a gale 8. But this moment is perfect”.

That perfect moment will not last long.

I interviewed polar explorer David Hempleman-Adams about the succeeding moments once Northabout had returned to the UK. It seems riding out the cyclone was the most frightening experience he had ever had.

The University of Alaska article references the following peer reviewed paper:

“Role of Intense Arctic Storm in Accelerating Summer Sea Ice Melt: An In Situ Observational Study“

The next on my list of must read papers comes complete with a video:

Continue reading Month in Review – Arctic Science Edition →

Facts About the Arctic in May 2021

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It’s May Day 2021, and just for a change we’re going to start the month off with a pretty picture!

Parts of the Laptev Sea are starting to look distinctly “warm” in the infra-red. Here’s a “false colour” image taken by the Terra satellite during a gap in the clouds:

We have reached the time of year when the SMOS “thin ice thickness” readings start being affected by surface melt, but let’s take a look anyway:

That area of the Laptev certainly appears to be either thin or melting.

Meanwhile on the Canadian side of the Arctic the fast ice off the Mackenzie Delta is starting to get damp, even though the river itself still looks to be fairly well frozen:

It will also be interesting to follow the progress of this large floe as it heads towards oblivion through the Fram Strait:

Continue reading Facts About the Arctic in May 2021 →

Allegedly “Unsettled Science” by Steven Koonin et al.

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In our recent article about the forthcoming G7 Summit in Cornwall we suggested that:

Climate change is top of the G7 agenda along with Covid-19, and you can rest assured that vested interests will not miss any opportunity to promote those interests over the next two months and beyond.

That has indeed proved to be the case! Let us count the ways.

Steven Koonin’s new book “Unsettled: What Climate Science Tells Us, What It Doesn’t, and Why It Matters” is being promoted (left?), right and centre by a veritable cornucopia of the usual suspects. In an endeavour to explain (to the mythical (wo)man in the street?) the ways in which “A lie will fly around the whole world while the truth is getting its boots on” I’ve performed a Google search for the phrase “climate science has drifted so far out of touch with the actual science as to be absurdly demonstrably false” by way of a demonstration:

65 “demonstrably false” clones of the WSJ article, and counting……

[Edit – April 24th]

This morning’s update on my “demonstration” Google search.

There are now 241 “demonstrably false” Kooninism clones, and counting……

Continue reading Allegedly “Unsettled Science” by Steven Koonin et al. →

Stop Attempts To Criminalise Nonviolent Climate Protest?

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It may not have come to your attention yet, but a long list of over 400 climate scientists have recently signed an “open letter” to the UK and other Governments requesting:

As academics researching climate and environmental change, we have been encouraged to see increased focus on climate in politics and society in recent years. Considering the current trajectory of planetary change, such attention is welcome, even though action is still lacking. We know that our research alone was not enough for this recent awakening to climate breakdown as an existential crisis for humanity, and recognise that protest movements around the world have raised the alarm…

But around the world today, those who put their voices and bodies on the line to raise the alarm are being threatened and silenced by the very countries they seek to protect. We are gravely concerned about the increasing criminalisation and targeting of climate protestors around the world…

With the upcoming Conference of the Parties of the UN Climate Change Convention (COP26) in Glasgow, and the urgency for global action accelerating as global warming already reaches 1.2°C, 2021 is a critical year for climate governance. It has become abundantly clear that governments don’t act on climate without pressure from civil society: threatening and silencing activists thus seems to be a new form of anti-democratic refusal to act on climate.

See for example this tweet from “Scientist Rebellion”, the militant academic wing of Extinction Rebellion UK?

The signatories to the open letter include a long list of well known names:

We, the undersigned, therefore urge all governments, courts and legislative bodies around the world to halt and reverse attempts to criminalise nonviolent climate protest.

  • Professor Julia Steinberger, Universities of Lausanne & Leeds
  • Dr Oscar Berglund, University of Bristol
  • Distinguished Professor Michael Mann, Penn State University
  • Professor Piers Foster, University of Leeds
  • Dr Leah Goldfarb, Universite Paris Saclay
  • Professor Catherine Mitchell University of Exeter
  • Dr Peter Gleick, Pacific Institute
  • Professor Stefan Rahmstorf, University of Potsdam

etc. etc.

On Monday the Guardian newspaper published an article about the climate scientist’s open letter:

That article has now disappeared from public view:

Continue reading Stop Attempts To Criminalise Nonviolent Climate Protest? →

The 2021 G7 Summit in Cornwall

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Our regular reader(s) will no doubt recall the good old days when several times each month an opportunity would present itself to debunk some “skeptical” nonsense from one or more of the usual suspects?

That all changed when Donald Trump was elected President of the United States. He was of course much more amenable to lobbying from fossil fuel interests than Barack Obama, and everything went (comparatively!) quiet.

Now that The Don has sailed off into the proverbial sunset and Joe Biden is top dog all that has changed. A return to the (not so) good old days comes as no surprise, and the porky pies have started coming off the denialospheric production line once again.

There have already been a few contrarian ripples on the surface of the climate science seas, which we may well come to in due course. However a set of substantial waves are now visible on the horizon. The proximate cause is the forthcoming summit of the G7 nations, which as luck would have it is taking place just down the road from the Great White Con winter holiday residence in North Cornwall. Then in November the COP26 conference is being held in Glasgow.

According to the G7 UK web site:

In June, Prime Minister Boris Johnson will welcome fellow G7 leaders to one of the most beautiful parts of the UK: Carbis Bay in Cornwall.

Other parts of the region will also play a key role in the Summit, including neighbouring St Ives, Falmouth and Newquay airport.

With over 400 miles of coastline, Cornwall’s stunning landscape provides a perfect setting for world leaders to come together and discuss how to respond to global challenges like coronavirus and climate change.

Here’s one of my recent pictures of some of that coastline, including part of Cornwall’s industrial heritage and some large waves!

Climate change is top of the G7 agenda along with Covid-19, and you can rest assured that vested interests will not miss any opportunity to promote those interests over the next two months and beyond. By way of example, one of our long standing “usual suspects”, Judith Curry, “tweeted” the following message to her followers on April 17th:

Continue reading The 2021 G7 Summit in Cornwall →

Facts About the Arctic in April 2021

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As part of his March PIOMAS gridded sea ice thickness update Wipneus also produced this graph of sea ice export from the central Arctic via the Fram Strait:

So far this winter export has been remarkably subdued, but that has now changed. A persistent dipole with high pressure over Greenland and low pressure over the Barents Sea is generating strong northerly winds in the Fram Strait, and even bringing some April snow showers to South West England:

Precisely how high the pressure has been over Greenland is the subject of much debate. See for example this discussion on the Arctic Sea Ice Forum about whether a new world high pressure record has just been set. Different weather forecasting models have come to very different conclusions about the mean sea level pressure of a high pressure area situated over the Greenland ice sheet, which reaches an altitude of over 3,000 metres. Here’s GFS for example, showing 1097 hPa at 06Z on April 4th:

whereas the Canadian Meteorological Centre synopsis for the same time shows a mere 1070 hPa:

At least all the assorted models agree that the isobars are closely packed over the Fram Strait, and hence some of the thickest sea ice remaining in the Arctic is currently heading towards oblivion in the far north Atlantic Ocean:

Here’s the US Navy’s sea ice drift forecast for Saturday 10th:

Continue reading Facts About the Arctic in April 2021 →

The 2021 Maximum Arctic Sea Ice Volume

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If the 2021 maximum Arctic sea ice extent is more your thing then please see the previous article:

“The 2021 Maximum Arctic Sea Ice Extent“

Maximum volume is still several weeks away, but let’s first of all take a look at the PIOMAS modelled volume numbers for February. They are not yet available via the University of Washington’s Polar Science Center web site, but Wipneus has once again crunched the gridded thickness numbers which are already available. Here is what they reveal:

As you can see, it will be a big surprise if the 2021 volume maximum occurs in March rather than April, and 2021 is currently 3rd lowest for the date, behind 2017 and 2018. For completeness here too is the PIOMAS thickness map for the end of February:

This does contain some surprises, such as an area of thick ice along the shore of the East Siberian Sea, but no such thing along the north coast of Greenland, the traditional bastion of “the thickest ice in the Arctic Ocean”.

The “measured” Arctic sea ice volume calculated from CryoSat-2 and SMOS thickness data has also updated to February 28th:

Note that the “near real time” figures graphed in blue will almost certainly be revised upwards when the “reanalysed” data is released in a couple of weeks. Equally certainly they will be “lowest for the date” in the 11 year record.

Here also is the CS2/SMOS thickness map for February 28th for comparison purposes:

Continue reading The 2021 Maximum Arctic Sea Ice Volume →

The 2021 Maximum Arctic Sea Ice Extent

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Here’s the latest graph of Arctic sea ice extent from JAXA/ViSHOP, with 2021 and 2015 highlighted:

Extent fell by over 100,000 square kilometres between February 16th and 17th! Can that steep fall continue, as it did for one more day in 2015?

Here too is Zack Labe’s 2021 overview of JAXA maximum extent over the previous couple of decades:

2015’s maximum was very early, on February 15th. Hence the current extremely tentative 2021 maximum is already both higher and later than that. The decadal average extent graphs show the date of the maximum getting later and later, and the 2010’s peaks in the middle of March.

It therefore seems likely that there is more freezing still to come this year. However lets take a look at the high resolution AMSR2 sea ice area graph for the Sea Of Okhotsk:

The recent fall in Arctic wide extent has evidently been driven by the recent rapid decline in this peripheral sea, where SMOS reveals more thin ice ripe for further melting:

In conclusion, the high res AMSR2 extent metric shows the tentative 2021 peak below that of 2015!

Continue reading The 2021 Maximum Arctic Sea Ice Extent →

Facts About the Arctic in November 2020

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Arctic sea ice volume is of course far more important in the grand scheme of things. However sea extent is easier to measure, and the JAXA AMSR2 flavour thereof has now nudged into second place for the date above 2016:

[Edit – November 4th]

The PIOMAS gridded thickness numbers have been released, to reveal this end of October thickness map:

and these calculated volume graphs:

These show Arctic sea ice volume to be lowest for the date, even if extent has slipped into 2nd place.

For comparison purposes here too is the latest AWI CryoSat-2/SMOS merged thickness map:

Continue reading Facts About the Arctic in November 2020 →