North Pole

A story on the BBC Business News website about the Northern Sea Route caught my eye:

BBC Business News “Container ship to break the ice on Russian Arctic route”. 21 August 2018.

The Danish ship Venta Maersk, (Maersk Line, ice-class Baltic feeder vessel  of 3,600 containers) is going to attempt to transit across the Kara Sea, the Laptev Sea and the East Siberian Sea.

Maersk said: “The trial passage will enable us to explore the operational feasibility of container shipping through the Northern Sea Route and to collect data.”

There is generally a lot happening in Arctic sea ice news at this time of the year as we head to the annual summer minimum extent, and current sea ice extent is currently about 1.6 million km² below the 1981-2010 mean.

Sea ice in the Arctic currently about 1.6 million km2 below the 1981-2010 mean. 21 August 2018.

Given that the trend of minimum ice extent has been relentlessly downwards since the start of the satellite record:

Annual Arctic minimum sea ice extent. Data from from NSDIC.

we could expect the Venta Maersk to have potentially an easy passage.

But that is rarely true in polar seas – even at the height of what will be the Arctic summer.

A look at the distribution of the current sea ice extent is interesting.

Arctic sea ice 21 August 2018, mean Arctic sea ice 21 August 1989-93 and difference between the two. Reds indicate absence of sea ice compared to the older data and blues indicate increased. The yellow box indicates a region where there is much more sea ice than we could expect.

There is more sea ice in the East Siberian Sea than we could expect (~40% more than the 1989-93 mean), and a look at the latest “near real time” (end of April 2018) ice thickness data from CPOM show that the ice in this region was quite thick at the start of the summer melt season.

Arctic sea ice thickness processed at UCL from CryoSat’s SAR mode data: NOTE THIS IS END OF APRIL 2018. NRT Service Suspended during Arctic summer (May-Sept).

It is possible the Venta Maersk could find the going slow, but she is a polar rated ship designed to work in the Baltic, and by staying close to the coast she could avoid the ice completely.

It is an interesting way to move a Baltic ship from it’s build location in China to its planned operational area, and one to watch over the next month.

The excellent researcher Dr Nathanael Melia wrote a great post about the potential of Arctic Shipping on Carbon Brief in 2016: What will sea ice loss mean for Arctic shipping?

**

Interestingly if you look at the Cryosat sea ice thickness map north of Greenland you can see that at the end of the winter the sea ice thickness was already relatively low. (See the story in the Guardian: Arctic’s strongest sea ice breaks up for first time on record). The thickest sea ice is further to the west north of the Canadian Arctic Archipelago.

Arctic sea ice thickness processed at UCL from CryoSat’s SAR mode data: NOTE THIS IS END OF APRIL 2018. NRT Service Suspended during Arctic summer (May-Sept).

***  UPDATE From Twitter

From Dr Stefan Hendricks at the Alfred Wegener Institute

Tweet from Dr Stefan Hendricks.

**** Update 2 from Twitter

From Dr Ruth Mottram at the Danish Meteorological Institute.

Tweet from Dr Ruth Mottram.

Iceberg A68 calved from the Larsen C ice shelf earlier this year. I wrote about before.

As the berg calved it is starting to reveal a patch of seafloor that has been covered by thick glacial ice, and as the BAS press release says this has revealed:

a mysterious marine ecosystem that’s been hidden beneath an Antarctic ice shelf for up to 120,000 years.

To have the chance of making  observations in an untouched environment like that is so exciting, that the British Antarctic Survey are running an expedition to investigate. You can read about it in a great piece by Victoria Gill on the BBC news site, and the brilliant Katrin Linse has done some great work with Radio 4 and the BBC Breakfast program (2hrs 20 mins in source BAS twitter account) explaining both the purpose and the work.

I was looking this morning at the recent Sentinel-1 imagery on Polarview, this is an image of A68 captured on 11 February 2018. It’s big – about 5,200 km2.

Iceberg A68 and the Larsen C Ice shelf captured from with the Sentinel-1 SAR sensor 11 February 2018.

I labelled some features in the image: the iceberg and the ice shelf are the relatively solid grey colour. The blue overlay is where land and the ice shelf roughly were (it’s called a land mask).

One thing you can see is the speckled grey colour which covers the top right hand side.

This speckled grey is sea ice.

It’s a relatively thin cover of a typically 1-3 m thick.

Antarctic Sea ice.

If you map the current sea ice distribution, and the location of iceberg A68 you can see how much sea ice they are going to have to sail through to reach the region.

Larsen C, the iceberg A68 and the sea ice extent on 11 February 2018.

There is a lot of high concentration sea ice between the ice edge and the iceberg that the ship will have to traverse. RRS James Clark Ross is a very capable ship, and she will be able to make way through the ice.

The issue is this can take a lot of time.

And time whilst ice breaking is fuel.

In open water a research ship can cover ~22 km per hour, in sea ice if you are breaking ice then maybe 5 km per hour would be good, and you probably wouldn’t break ice 24 hours per day.

They have 3 weeks.

Plus if you sail 400 km in the ice, unfavourable winds can easily compress the sea ice and trap a ship. It’s happened before, and in the modern era even capable ships get can get held up.

The satellite I used to make the image doesn’t do so well in coastal regions, so given some favourable winds there could be a nice channel for them. I am going to be watching the visible satellite imagery for that.

It’s easy to make pronouncements from 14,000 km away, but really the people on the ground will  work it out.

Whatever happens I know that the researchers on board will do some great research. Plus I would be surprised if A68 moves too far from the region in the next year.

Breaking ice in Antarctica.

Breaking Antarctic sea ice on the RRS James Clark Ross.

(Apologies to the Rolling Stones  for the title,

But if you try sometimes, you might find you get what you need.

*** Update 16 Feb 2028

This on twitter from Dr Stef Lhermitte

At the moment they will have to get through ~300 km of sea ice.

This is a MODIS image from 2004, but it’s too good not to post here.

Iceberg A38 at South Georgia 12 April 2004

I’m giving a talk tonight for the South Georgia Association called Giant Icebergs and South Georgia, so I’m wandering through a lot of these images at the moment.

South Georgia is a small island approximately 190 x 30 km within the Antarctic Circumpolar Current in the South Atlantic. It has a continental shelf that extends more than 50 km from the coast with average depth ~200 m, although there are deeper submarine canyons.

A38 is about 300 Gt in mass, so it’s really significant. The work I was doing on this was picked up in 2010 by the BBC in a story called Giant icebergs head to watery end at island graveyard.

I love looking at satellite images of the Antarctic and picking out the icebergs. In the last few years we have had great stories about the giant icebergs A68 in 2020, A76 in 2022 and most recently A23a currently in the Southern Scotia Sea.

At the moment there are two of very large icebergs at the southern end of Antarctic Sound. Here is a map to orientate yourself and show where they are.

A basemap with a MODIS image from 7 October 2024. The yellow box is the location of Antarctic Sound and is expanded on below.

There is a lot in the image above. As well as the Antarctic Peninsula there are clouds, sea ice, and icebergs. Zooming into Antarctic Sound shows the giant icebergs more clearly.

A MODIS satellite image of Antarctic Sound taken on 7 October 2024. Two large icebergs are at the southern end of the Sound. These are A80A and A76C.

And in the radar sensor on Sentinel-1 the icebergs leap out because that sensor “sees” through the clouds.

A Sentinel-1 SAR image from 8 October 2024. Land is coloured blue, the giant icebergs are solid grey, and sea ice and smaller icebergs make up the grey shades colouring the rest of the image.

A80A is 10×9 nautical miles and it calved from the Larsen D Ice Shelf in November 2022. A76C is currently 16×7 nautical miles and was part of iceberg A76 that calved from the Ronne Ice Shelf in May 2021. These are pretty decent sized icebergs: A80A looks to be pinned against Rosamel Island and Andersson Island at the southern end of Antarctic Sound, and A76C grounded against A80A.

Personally I would be surprised if they broke out before the start of the Antarctic season proper, so they could cause some complexities in navigating into the Weddell Sea through Antarctic Sound.

Finally we can’t forget the current monster of them all: A23A at 40×32 nautical miles, and it has been spinning above Pirie Bank north of the South Orkney’s since April 2024. I described it as “the iceberg that just refuses to die” when I spoke to the BBC, and it has been spinning for seven months in pretty much the same location. When it finally breaks free, it’ll head up towards South Georgia and it’s inevitable demise rapid demise.

A MODIS satellite image from 13 October 2024 showing iceberg A23A just north of the South Orkney Islands.

It’s amazing to think that A23A has been in existence since 1986 when it fractured from the Filchner-Ronne Ice Shelf.

The summary? It looks like if you’re going South this season you could see some very big icebergs, and navigation could be complicated in the North West Weddell Sea.

I was asked recently for some black and white pictures of me for an event. Here they are.

Mark Brandon, Antarctica Mark Brandon in the Arctic in front of a small iceberg Mark Brandon in Iceland

This is the Official Citation for the Times Higher Education Most Innovative Teacher of the year

Receiving the Most Innovative Teacher of the Year Award.  
From L-R David Walliams, Me, Professor David Gibson, and Professor Craig Mahoney

Most Innovative Teacher of the Year

Mark Brandon, The Open University

Mark Brandon has worked alongside Sir David Attenborough as principal scientific adviser for the Bafta award winning BBC television series Frozen Planet, written the most popular study unit ever on The Open University’s OpenLearn website and given a sell-out presentation at the 2012 Cheltenham Science Festival.

Researching and teaching about the polar regions is Dr Brandon’s passion, and his innovative approach to teaching has inspired students to break Open University registration records to get a place on his course.

Work on the Frozen Planet documentaries convinced Dr Brandon that inspirational, imaginative and accessible teaching material about polar science could reach a large audience. His undergraduate course, The Frozen Planet, is accompanied by a book, online teaching activities and exclusive film clips of him teaching science in the Arctic.

Dr Brandon has sparked an interest in polar geography in thousands of pupils with his talks in schools. Indeed, with visitors to the ancillary website approaching half a million and 15,000 people worldwide having read the first chapter of his book online, Dr Brandon’s innovative approach has led to people across the spectrum taking up the study of the Arctic and the Antarctic.

Craig Mahoney, chief executive of the Higher Education Academy and one of the awards judges, said: “The metrics associated with student registrations, viewer interest, resource development, testimonial support, student feedback and a sustained commitment from The Open University, make Mark an outstanding choice.”

Sponsored by Higher Education Academy

The Citation as printed.

In my career I’ve been very lucky to visit the Arctic and the Antarctic multiple times. Here is a list of the polar trips I’ve been on.

The Nathanial Palmer and the Akademik Fedorov in the Weddell Sea, Antarctica in 1992. Mark Brandon on the sea ice of the Arctic Ocean doing his PhD research in 1993

1989 MV Sea Searcher North East Atlantic, Greenland-Iceland-Norwegian Sea experiment (NEAT-GIN) This trip was organised by the Admiralty Research Establishment. Much of the oceanographic work was classified and working on the Arctic Fronts. I managed to find the unclassified data. (Cruise dates 26 August to 4 October 1989).

1992 Nathanial Palmer Voyage NBP92-01 This was maiden voyage of the Nathanial Palmer and we sailed to the Antarctic in the Austral Winter. As a Scott Polar Research Institute person I was conducting sea ice research in the Weddell Sea, and I deployed an ice-ocean environmental buoy (the fore runner of what are now ice tethered profilers). The cruise was also to change personal at the ground-breaking Ice Station Weddell (ISW-1), and you can see in the picture above it was a joint American and Russian expedition.

Deploying the ice-ocean environmental buoy through the sea ice of the Weddell Sea. Late April 1992. Deployment of the Ice Ocean Environment Buoy in the Weddell Sea in 1992.
From L-R: Mark Brandon, Bill, and Barry Lopez.

ISW-1 remains the only drifting ice station experiment conducted in the Weddell Sea. (Cruise dates 16 April 1992 to 16 May 1992).

1993: MV Northern Horizon, to the North Greenland Sea This was part of my PhD research and we were surveying the development of the Odden Ice Tongue so I could understand how the formation of sea ice changed the ocean just beneath. (Cruise dates: 27 January 1993 to 19 February 1993).

1993: Polarstern Cruise ARK IX/1a and ARK IX/1b to the high Arctic Ocean. Again this was part of my PhD research, and this was the hardest trip I did and the ship sailed up into the Arctic ocean, frozen into the pack and then drifted south towards Svalbard. It really was exhausting, but quite the polar education with air temperatures typically around -30°C with wind chill on top of that.

Peter Wadhams (L) and Mark Brandon (R) drilling sea ice in the Arctic Ocean to measure the thickness. March 1993.

“The air temperature was -37°C (wind chill -65° to -70°C).

Eicken, H. and Meincke, J. (1994): The expedition ARKTIS-IX/1 of RV “Polarstern” in 1993 , Berichte zur Polarforschung

It was so cold that ice froze to the superstructure of the ship and we had to break it off with mallets and axes. Desperate work, and I can only imagine what that activity would have been like on a sailing ship back in the heroic age.

Breaking ice from the forward crane of the RV Polarstern as it steams northwards into the Arctic Ocean, March 1993. RV Polarstern frozen into the sea ice of the Arctic Ocean and drifting south with the pack ice on ARK IX/1. Peter Wadhams is crossing a crack in the ice to get back to the ship.

Yes I did get burnt by the cold a few times on my face, toes and fingertips. (Cruise dates 26 February 1993-17 April 1993).

Polarstern frozen in the pack ice of the Arctic Ocean, March 1993. Returning to the Polarstern by helicopter as it sits in the Arctic pack ice.

1996: RRS James Clark Ross Cruise 11 (JR11) to South Georgia. This was my first cruise as a member of the British Antarctic Survey, and I led the physical oceanographic program on the two month voyage. (Cruise dates 1 January 1996 to 27 February 1996).

1996: RRS James Clark Ross Cruise 16 (JR16) To Rothera and Antarctic Peninsula as part of the World Ocean Circulation Experiment. Oceanographic measurements were made across Drake Passage, and were reported by the Southampton Oceanography Centre. (Cruise dates 13 November 1996 – 5 December 1996).

1996-7: RRS James Clark Ross Cruise 17 (JR17) to South Georgia. Once more I led the physical oceanography program in the ex whaling grounds around the polar island. (Cruise dates 12 December 1996 to 5 January 1997).

1997: RRS James Clark Ross Cruise 25 (JR25) to South Georgia and I led the physical oceanography program for the “Spring Processes Cruise”. My personal diary talked about the “challenging conditions”, but I have great memories of this one. (Cruise dates 21 October 1997 to 14 November 1997).

1997: RRS James Clark Ross Cruise 26 (JR26) to the South Georgia, The Scotia Sea and Antarctic Peninsula Project GeneFlow. Once more I led the physical oceanography program and this was a hugely memorable trip with both brilliant work, and some amazing scenery. (Cruise dates 17 November 1997 to 14 December 1997).

1997-8: RRS James Clark Ross Cruise 27 (JR27) to Rothera and the Antarctic Peninsula as part of the World Ocean Circulation Experiment. Once more we were making measurements of the strength of the Antarctic Circumpolar Current across Drake Passage. (Cruise dates 17 December 1997 – 8 January 1998).

1998 RRS James Clark Ross Cruise 28 (JR28) to South Georgia, leading once more the physical oceanographic program around the island in the 4th year of the 5 year British Antarctic Survey Marine Life Sciences Division program. (Cruise dates 14 January 1998 to 7 February 1998).

1999: RRS James Clark Ross Cruise 40 (JR40) ALBATROSS – Antarctic Large-scale Box Analysis and The Role of the Scotia Sea. This was a wonderful cruise that involved a circumnavigation of the Scotia Sea, work around South Georgia and across Drake Passage, and a visit to Rothera to replace a faulty CTD wire. I was a member of the physical oceanography program. (Cruise dates 15 March 1999 to 22 April 1999).

2000: RRS James Clark Ross Cruise 47 (JR47) The CCAMLR Synoptic Survey studying the krill distribution in the Scotia and Bellingshausen seas. This was a large four ship multi nation survey of the Scotia Sea and was the physical oceanography lead.

At the Shackleton waterfall at Stromness, South Georgia. You can see the RRS James Clark Ross just offshore. From left to right people are (unknown), Mark Brandon, Lizzie Hawker, Andrew Brierley and Richard Bridgeman. February 2000.

The other three ships were the R.V. Kaiyo Maru, the R.V. Yuzhmorgeologiya, and the R.V. Atlantida. (Cruise dates 13 January 2000 – 17 February 2000).

2001: RRS James Clark Ross Cruise 58 (JR58) Research cruise to the Weddell Sea. This was the first time we used the AUV Autosub beneath the sea ice of the Weddell Sea, as part of Under Sea Ice and Pelagic Surveys (USIPS): fisheries- and plankton-acoustics, and oceanographic investigations of otherwise-impenetrable environments project. I admit it is not the most catchy grant title but the work we published in Science showed the first evidence of large krill swarms beneath the Antarctic sea ice.

Preparing Autosub for deployment in poor conditions. In these early AUV missions there wasn’t any cover on deck for the vehicle, or the people working on it. February 2001.

I led the sea ice and oceanographic work. (Cruise dates 22 January 2001 – 15 February 2001).

2003: RRS James Clark Ross Cruise 84 (JR84) After our success with JR58, we once more took the AUV Autosub south on the AUTOSUB Under Ice (AUI) Pine Island cruise. I was co-scientist in Charge leading sea ice and oceanographic investigations at Pine Island as a component of the Autosub Under Ice programme.

Mark Brandon on the deck of the RRS James Clark Ross close to Pine Island and Thwaites Glacier. March 2003.

Whilst the AUV work wasn’t as successful as we would have hoped, the oceanographic work was extremely successful. (Cruise dates 28 February 2003 to 4 April 2003).

2004: RRS James Clark Ross Cruise 96 (JR96) to South Georgia. I won a research grant to deploy moorings at South Georgia, and so I was once again south to lead oceanographic work and a mooring recovery and redeployment. (Cruise dates 30 December 2003 to 20 January 2004).

On a rare day off, boating in front of the Harker Glacier at South Georgia.

Then things got a little complicated! Cruise numbers were allocated before actually going, and sea ice problems meant that JR115 came before JR112.

2005: RRS James Clark Ross Cruise 115 (JR115) To Rothera and Antarctic Peninsula as part of the World Ocean Circulation Experiment. One can never miss an opportunity to measure the strength of the Antarctic Circumpolar Current, and we made oceanographic measurements across Drake Passage.

Breaking through the sea ice of the Bellingshausen Sea on the RRS James Clark Ross. Photograph taken from the bridge wing. December 2004.

We had intended to work in Marguerite Bay, but were stopped by sea ice. (Cruise dates 1 December 2004 to 19 December 2004).

2005: RRS James Clark Ross Cruise 112 (JR112) Antarctic Peninsula and working in Marguerite Bay. I won a research grant to deploy moorings to measure the physics and biogeochemistry beneath the sea ice.

A sediment trap just about to enter the water from RRS James Clark Ross during a mooring deployment. January 2005

I was Scientist in Charge on this one. (Cruise dates 20 January 2005 to 30 January 2005).

2007: RRS James Clark Ross Cruise 165 (JR165) Marguerite Bay, King George VI Sound and along all the ice shelves south-west to Lambert Island. I think this was one of my favourite research cruises and the research and scenery were amazing. At the end of the cruise we tacked on cruise JR174 which was a mooring deployment and recovery that I led. (Cruise dates 26 February 2007 to 16 April 2007).

The RRS James Clark Ross in the sea ice of the Bellingshausen Sea. I was part of a team working on the sea ice as the sun went down. March 2007.

If I add up all the polar days I’ve spent 624 days in total in the polar regions, 142 in the Arctic and 484 in Antarctica.

2010 BBC Frozen Planet. Because of my field experience from 2008-2012 I was the lead academic advisor on the BBC series Frozen Planet, and this meant that in 2010 I spent time with the BBC in Svalbard filming. It was a wonderful trip and I did lots of filming for the Open University Course that I won the Innovative Teacher of the Year award. (Dates 12 April 2010 – 22 April 2010).

Mark Brandon and Sir David Attenborough whilst filming for the BBC series Frozen Planet.

When I work with broadcast companies it is very helpful to have an up to date understanding of the conditions and subjects available at at various accessible Antarctic sites, so I have taken the opportunity to work with tour companies to allow access.

Gentoo penguins, Petermann Island on the Antarctic Peninsula.

On MS Explorer

2002 Antarctic Peninsular and South Georgia. (Cruise dates 3 February 2002 to 24 February 2002).

2003 Antarctic Peninsular and South Georgia (Cruise dates 4 January 2003 to 5 February 2003).

Mark Brandon at Devil Island in the Northen Weddell Sea. Mark Brandon driving a zodiac off South Georgia.

On MS Island Sky

2019 Antarctic Peninsula and South Georgia. (Cruise dates 1 December 2019 to 22 December 2019).

2022 Antarctic Peninsula and South Georgia (1 December 2022 to 22 December 2022).

2023 Antarctic Peninsula and South Georgia (12 November 2023 to 1 December 2023).

And when I add everything up, that’s 750 days. A long way from the east end of London.

The Prince Gustav Channel was covered by an ice shelf which collapsed in the 1990’s, and for many years it was possible to sail a ship around James Ross Island.

Recently it has been covered with sea ice frozen to the land – we call this fast ice, and it’s usually only a few metres thick of frozen sea water – rather than hundreds of metres thick snow derived ice shelf.

Recent images from the TERRA satellite show that this fast sea ice is finally breaking out.

It’ll soon be possible to circumnavigate James Ross Island once more.

The Prince Gustav Channel early spring Antarctic summer 2016/7 from MODIS satellite imagery on the TERRA satellite.

This map shows the location of the channel.

The Antarctic Peninsula showing the location of the Prince Gustav Channel.

Now it has started I wonder how long it will take to finally clear. Or more fun, I wonder if tour ships will be able to get around the island?

Mark Brandon • October 15, 2024

I love looking at satellite images of the Antarctic and picking out the icebergs. In the last few years we have had great stories about the giant icebergs A68 in 2020, A76 in 2022 and most recently A23a currently in the Southern Scotia Sea.

At the moment there are two of very large icebergs at the southern end of Antarctic Sound. Here is a map to orientate yourself and show where they are.

A basemap with a MODIS image from 7 October 2024. The yellow box is the location of Antarctic Sound and is expanded on below.

There is a lot in the image above. As well as the Antarctic Peninsula there are clouds, sea ice, and icebergs. Zooming into Antarctic Sound shows the giant icebergs more clearly.

A MODIS satellite image of Antarctic Sound taken on 7 October 2024. Two large icebergs are at the southern end of the Sound. These are A80A and A76C.

And in the radar sensor on Sentinel-1 the icebergs leap out because that sensor “sees” through the clouds.

A Sentinel-1 SAR image from 8 October 2024. Land is coloured blue, the giant icebergs are solid grey, and sea ice and smaller icebergs make up the grey shades colouring the rest of the image.

A80A is 10×9 nautical miles and it calved from the Larsen D Ice Shelf in November 2022. A76C is currently 16×7 nautical miles and was part of iceberg A76 that calved from the Ronne Ice Shelf in May 2021. These are pretty decent sized icebergs: A80A looks to be pinned against Rosamel Island and Andersson Island at the southern end of Antarctic Sound, and A76C grounded against A80A.

Personally I would be surprised if they broke out before the start of the Antarctic season proper, so they could cause some complexities in navigating into the Weddell Sea through Antarctic Sound.

Finally we can’t forget the current monster of them all: A23A at 40×32 nautical miles, and it has been spinning above Pirie Bank north of the South Orkney’s since April 2024. I described it as “the iceberg that just refuses to die” when I spoke to the BBC, and it has been spinning for seven months in pretty much the same location. When it finally breaks free, it’ll head up towards South Georgia and it’s inevitable demise rapid demise.

A MODIS satellite image from 13 October 2024 showing iceberg A23A just north of the South Orkney Islands.

It’s amazing to think that A23A has been in existence since 1986 when it fractured from the Filchner-Ronne Ice Shelf.

The summary? It looks like if you’re going South this season you could see some very big icebergs, and navigation could be complicated in the North West Weddell Sea.

Posted in Science, Uncategorized. Tags: Antarctic Peninsula, Antarctic Sound, antarctica, iceberg, Icebergs on October 15, 2024 by Mark Brandon. Mark Brandon • August 31, 2018

Just over a year ago in July 2017 iceberg A68 calved from the Larsen C Ice Shelf. I appeared on BBC News before it actually calved explaining what was happening.

At first A68 was slow to move and as I predicted back then, it likely got stuck on the sea bed (we say “grounded”). It has stayed pretty much in the same place through to July 2018.

But now A68 has started to swing northwards.

As the light is coming back to Antarctica, at high latitudes visual imagery is very washed out. But if we look at other data such as the brightness temperature, you can see some striking features.

This image is from 20 August 2018.

Corrected Reflectance (True Color) from the Suomi NPP Visible Infrared Imaging Radiometer Suite (VIIRS), and the Brightness Temperature (Band I5, Day). Image from 20 August 2018.

With the brightness temperature data set, brighter colours indicate higher temperatures. The Larsen Ice shelf and A68a are glacial ice and so cold, they appear dark purple. The sea ice is thinner and warmer and in contact with the ocean so the purple shade is lighter. The leads which are cracks in the sea ice and so open water and / or very thin sea ice appear as relatively bright lines. On the bottom right of that image you can see that under certain circumstances the brightness temperature data set can see through clouds.

…continue reading →

Posted in Science. Tags: A68, antarctica, satellite, sea ice on August 31, 2018 by Mark Brandon. Mark Brandon • February 13, 2018

Iceberg A68 calved from the Larsen C ice shelf earlier this year. I wrote about before.

As the berg calved it is starting to reveal a patch of seafloor that has been covered by thick glacial ice, and as the BAS press release says this has revealed:

a mysterious marine ecosystem that’s been hidden beneath an Antarctic ice shelf for up to 120,000 years.

To have the chance of making  observations in an untouched environment like that is so exciting, that the British Antarctic Survey are running an expedition to investigate. You can read about it in a great piece by Victoria Gill on the BBC news site, and the brilliant Katrin Linse has done some great work with Radio 4 and the BBC Breakfast program (2hrs 20 mins in source BAS twitter account) explaining both the purpose and the work.

I was looking this morning at the recent Sentinel-1 imagery on Polarview, this is an image of A68 captured on 11 February 2018. It’s big – about 5,200 km2.

Iceberg A68 and the Larsen C Ice shelf captured from with the Sentinel-1 SAR sensor 11 February 2018.

I labelled some features in the image: the iceberg and the ice shelf are the relatively solid grey colour. The blue overlay is where land and the ice shelf roughly were (it’s called a land mask).

One thing you can see is the speckled grey colour which covers the top right hand side.

This speckled grey is sea ice.

It’s a relatively thin cover of a typically 1-3 m thick.

Antarctic Sea ice.

If you map the current sea ice distribution, and the location of iceberg A68 you can see how much sea ice they are going to have to sail through to reach the region.

Larsen C, the iceberg A68 and the sea ice extent on 11 February 2018.

There is a lot of high concentration sea ice between the ice edge and the iceberg that the ship will have to traverse. RRS James Clark Ross is a very capable ship, and she will be able to make way through the ice.

The issue is this can take a lot of time.

And time whilst ice breaking is fuel.

In open water a research ship can cover ~22 km per hour, in sea ice if you are breaking ice then maybe 5 km per hour would be good, and you probably wouldn’t break ice 24 hours per day.

They have 3 weeks.

Plus if you sail 400 km in the ice, unfavourable winds can easily compress the sea ice and trap a ship. It’s happened before, and in the modern era even capable ships get can get held up.

The satellite I used to make the image doesn’t do so well in coastal regions, so given some favourable winds there could be a nice channel for them. I am going to be watching the visible satellite imagery for that.

It’s easy to make pronouncements from 14,000 km away, but really the people on the ground will  work it out.

Whatever happens I know that the researchers on board will do some great research. Plus I would be surprised if A68 moves too far from the region in the next year.

Breaking ice in Antarctica.

Breaking Antarctic sea ice on the RRS James Clark Ross.

(Apologies to the Rolling Stones  for the title,

But if you try sometimes, you might find you get what you need.

*** Update 16 Feb 2028

This on twitter from Dr Stef Lhermitte

#MODIS Aqua of yesterday on https://t.co/RPVpONbwcO has a clear view (i.e. few clouds) of the area, nicely showing the high sea ice concentration and potential difficulty to reach iceberg #A68 pic.twitter.com/iti8tXmL6C

— Stef Lhermitte (@StefLhermitte) February 16, 2018

At the moment they will have to get through ~300 km of sea ice.

Posted in Science. Tags: A68, antarctica, Larsen C, RRS James Clark Ross, Science, sea ice on February 13, 2018 by Mark Brandon. Mark Brandon • November 24, 2017

Being interested in the Weddell Polynya I plotted some time series data from 1 September 2017 to 23 November 2017. On the left-hand panel, you can see the see the sea ice concentration, on the right-hand panel, the anomaly of the concentration each day compared with a mean from 1989-93.

The Weddell Polynya is the low concentration region at approximately 12:00 in the movies below.

You can see the Weddell Polynya isn’t stationary.

You can also see the sea ice is still relatively low compared to the historic record. We should expect this after the extreme low sea ice from ~October 2016 onward.

Antarctic sea ice extent (with greater >15% sea ice cover) 23 November 2017. From NSIDC.

I will write some more about this next week but for interest here is the Antarctic sea ice extent anomaly for 2017.

I made these movies using the excellent Antarctic Mapping Toolbox by Chad Greene. Antarctica is the Landsat Image Mosaic Of Antarctica (LIMA), and the coastline and shelf outlines come from the BEDMAP2 data set. Sea ice data is from NSDIC.

Posted in Science. Tags: anomaly, antarctica, sea ice, Weddell Polynya on November 24, 2017 by Mark Brandon. Mark Brandon • November 20, 2017

Antarctic sea ice extent remains low compared with the 1981-2010 median extent. This image shows the mean from 1989-93, the extent on 20 November 2017 and the difference between the two. Red colours imply that there is a decreased sea ice extent compared with the mean.

The mean Antarctic sea ice for the years 1989-93 on 20 Nov, the sea ice concentration on 20 Nov 2017 and the difference between the two data sets. Reds imply decreased sea ice compared with the mean, blue shades imply more. The original data come from the DMSP SMMI data set at the NSIDC.

And obvious low region is the vicinity of the Weddell Sea Polynya. I have written about the polynya this season on 17 September and 25 September, as well showing how it developed through the winter on 11 September 2017.

Something exciting is happening in the ocean under the polynya, and based on new data sources such as the SOCCOM buoy that surfaced in the polynya:

Last month, SOCCOM scientists were astonished to discover that a float in the Weddell Sea had surfaced inside the polynya, making contact with satellites in the dead of winter. Its new ocean measurements, transmitted when it surfaced, are being analyzed as part of a study in preparation on Weddell Sea polynyas. With these new observations comes the possibility that the polynya’s secrets may finally be revealed.

We should expect some exciting research articles soon.

Sea ice extent currently ~1.2 million km² low

The overall sea ice extent is currently ~1.2 million km² below 1981-2010 median extent. This sounds a lot.

Antarctic sea ice extent (with greater >15% sea ice cover) 18 November 2017. From NSIDC.

But at this time of the year the Antarctic sea ice is about to dramatically fall as spring develops. If spring “arrives” early then the extent will – as we see, be relatively low.

Seasonal cycle of Antarctic sea ice extent

Whilst the full on development and opening of the Weddell / Maud Rise Polynya is unusual, if you compare the sea ice on 18 November 2017 with the extent from the same day on 1989-1995 it is clear that the extent is often lower over Maud Rise, at this time.

This is the sea ice on 18 November for 1989, 91, 92, 93, 94, 95 and 18 November 2017. The original data come from the DMSP SMMI data set at the NSIDC.

I will keep watching the sea ice as the summer season develops

MODIS mosaic from the AQUA satellite on 18 November 2017.

** UPDATED 20th November 2017 replacing the first figure from 17  November to 20 November.

Posted in Science. Tags: antarctica, extent, Maud Rise, sea ice, SMMI, Weddell Polynya on November 20, 2017 by Mark Brandon. Mark Brandon • October 26, 2017

As daylight has returned to Antarctica it is straightforward to pick out polynya forming on the edge of the Antarctic continent.

This one by the Stange Ice Shelf and Rydberg Peninsula caught my eye. It is a latent heat polynya formed as the winds push the sea ice away from the land to reveal the ocean that appears black beneath.

The wispy trails of grey which appear in the black are new sea ice forming as frazil ice.

A latent heat polynya forming in front of the Rydberg Peninsula and Stange ice Shelf, 22-26 October 2017.

This is the location of the peninsula.

The location of the Rydberg Peninsula.

I visited that area in 2007 and took this picture. You can a thin skim of young nilas ice in front of the ice shelf, and sea smoke too.

The Stange Ice Shelf with a thin skim of sea ice in front. Posted in Science. Tags: antarctica, frazil ice, polynya, Rydberg Peninsula, satellite, sea smoke, Stange Ice shelf on October 26, 2017 by Mark Brandon. Mark Brandon • September 27, 2017

The polynya over Maud Rise was visible in a beautiful clear MODIS image on 25 September. It is currently ~40,000 km² of open water in the middle of the Antarctic winter sea ice. This will be some impressive heat loss.

MODIS image of the polyna over Maud rise on 25 Sept 2017. The black is ~40,000km2 of open water.

This is the polynya in the SMMI Data for the same day.

Location of Maud Rise polynya 25 Sept 2017.

A while back I calculated the heat loss through 2,000 km2 of open water in the Arctic as being ~600 GW. This is about 20 times as much open water…

As I said then, the heat loss is making the surface waters denser, so they sink away from the surface

More to come on this I expect.

Posted in Science. Tags: antarctica, Maud Rise, polynya, Weddell Sea on September 27, 2017 by Mark Brandon. Mark Brandon • September 19, 2017

Quick post on the Maud Polynya in the Weddell Sea that I wrote about last week. This is the sea ice data 17 September 2017, and the polynya is both clear and large.

The location of the polynya over Maud Rise. Sea ice data from DMSP SMMI.

An enlargement of the polynya shows that it is practically open water.

…continue reading →

Posted in Science. Tags: antarctica, Maud Rise, polynya, sea ice, Weddell Polynya, Weddell Sea on September 19, 2017 by Mark Brandon. Mark Brandon • September 11, 2017

The Weddell Sea polynya is an area of open water that sometimes appears in the Weddell Sea over a relatively shallow region called Maud Rise.

The Antarctic sea ice concentration 9 September 2017. The location of the polynya is marked and the original data come from the DMSP SMMI data set at the NSIDC.

In the latest satellite imagery from the DMSP satellite you can see the lower concentration sea ice as the darker blue colour. If you look at the MODIS imagery for the same date you can clear see black which indicates open water in the pack ice.

The MODIS imagery mosaic of Antarctica from 7 September 2017 from the MODIS sensor on the Terra satellite. The pattern in the centre of the image is because high latitudes of Antarctica are still dark at this time in winter.

…continue reading →

Posted in Science. Tags: antarctica, Maud Rise, MODIS, polynya, satellite, SMMI, SMOS, Weddell Sea on September 11, 2017 by Mark Brandon. Mark Brandon • July 18, 2017

Project MIDAS shows us that the iceberg A68 is about one trillion tonnes.

This is the Antarctic Peninsula and the outline of A68 from the satellite image on 14 July 2017 shown in black. The ice front is from the Bedmap2 data set (so a little out of date), and the bathymetry from the IBCSO data set.

Larsen C Ice shelf on the Antarctic Peninsula and the location and area of iceberg A68. The outline of A68 is derived from a satellite image of the ice shelf 14 July 2017.

There are some astonishingly beautiful processed satellite images of A68 out there such as this one via ESA from Adrian Luckman and the excellent Project MIDAS.

One image I haven’t seen is how good is knowledge of the bathymetry around A68?

The iceberg is going to drift and likely ground quite quickly. (I wrote about this on the conversation a while ago: When an Antarctic iceberg the size of a country breaks away, what happens next?)

In the map below, the shaded colour is the distance of any point on the sea bed to the closest actual depth measurement.

The distance to the nearest good depth measurement around the Antarctic Peninsula.

So the dark blue stripes labelled in the Weddell Sea are actually ship tracks – and the dark colours are good depth data. These measurements will have been made by icebreaker.

Just in front of A68 there is a very large area where no ship has been within ~80 km.

One small note on the size. I digitized the iceberg from a satellite image (a KML File can be downloaded). On twitter today there were satellite images showing fractures already.

New crack on eastern side of Iceberg A68 carves out large chunk of ice, as berg moves further away from #LarsenC Ice Shelf @deimosimaging pic.twitter.com/NagHUSUuH8

— The Antarctic Report (@AntarcticReport) July 18, 2017

But Martin O’Leary of the MIDAS team posted today on twitter that to the untrained eye looks like iceberg, is very likely fast ice (so thick sea ice that is “fast” to A68 – but only a few metres thick.)

Pretty sure this is some fast ice (i.e. sea ice, maybe a few meters thick) detaching from the berg. Looks totally different in SAR imagery https://t.co/XHDGle0gVv

— Martin O’Leary (@mewo2) July 18, 2017

Posted in Science. Tags: A68, Antarctic Peninsula, antarctica, bathymetry, Larsen C, Weddell Sea on July 18, 2017 by Mark Brandon.