When the winds are strong north of Siple islands during winter…

… the flow of warm water into the Getz ice shelf cavity is reduced! Wonder why? Well, Ph.D. Nadine Steiger (who successfully defended her thesis yesterday! Yippie and congratulations, Dr. Nadine!) nicely explains it in a newly published paper:

Intermittent reduction in ocean heat transport into the Getz Ice Shelf cavity during strong wind events (GRL)

Here’s a short version:

1) Eastward wind will (in the southern hemisphere) cause the surface water to move southward. (Oceanographers call this the “Ekman transport”). Water will hence pile up along the coast, along the green lines in the figure below.

Map showing winds (red arrows), Ekman transport (black arrows) and areas with coastal downwelling (green). Courtesy: N. Steiger

2) When surface water piles up along the coast, it will press down the warmer water below (Oceanographers call this “coastal downwelling”)

Ekman transport towards the coast will press the warm water deeper down. Courtesy: N. Steiger

3) The disturbance (i.e. the signal with depressed warm water) will travel along the coast (Oceanographers would call this a coastally trapped, internal wave. The wave is “internal” because the signal is traveling on the interface between two water masses, not on the ocean surface) and reaches the western Getz ice front 3 days after the storm! The figure below shows the observed temperature& salinity in the vicinity of the ice front, and below you see the wind and sea ice concentration. Each time the temperature at depth drops (marked by green triangles) there has been a storm just before!

4) When the wave arrives at the ice front, two things happen. Firstly the thickness of the warm water layer is greatly reduced (see above) and, secondly, the current changes direction so that the flow at depth is aligned with the ice front rather than to enter the ice shelf cavity like it normally does.

Observed mean currents (and temperature) during a) the cold events and b) the deployment period. Courtesy: N. Steiger

During the winter of 2016, this happened at least eight times – causing a reduction of the heat transport into the cavity by about 25%!

Well done, Dr. Steiger!!!

PhD. Nadine Steiger and a proud, ex. supervisor. Photo Andreas H. Opsvik

 

 

 

 

Good news from NFR!

What a morning! Scrolling through the newly published list of funded projects from the Norwegian Research Council while sipping your breakfast tea and finding this:

is even better than learning that Sweden qualified for the quarter-finals yesterday!

… and further down on the list I found this:

where I’m also involved!

I’m super excited to lead/join these interdisciplinary projects on Norwegian/Greenlandic fjords and climate change!

Masfjorden, here we come! The Bjerknes Center will fund our multi-disciplinary fjord project!

Yesterday the Bjerknes administration announced which of the “internal projects” they are to fund during the next four years – and I was very excited and happy to learn that our multi-disciplinary fjord project (led by Mari Myksvoll) was one of them!

Together with paleo-oceanographers and biologists, we will dive deep into the basins (and the mud/sediments) of Masfjorden to study how (and why) oxygen concentrations have varied in the “recent past” (the last 400yrs or so) and how that affects the ecosystem in the fjord.

I’m really looking forward to working locally – not only “locally” as in a nearby fjord, but also “locally” as in “together with colleagues in neighboring offices and buildings”! It’s is such a great team!

Proposal-funding-celebration outside GFI earlier today with parts of the new “Fjord-team”!

 

 

Do you miss Ninja?

Well – don’t worry! Dr. Ruth Mottram, a Climate scientist at the Danish Meteorological Institute is on her way to the Greenland Ice sheet and she is bringing “Ice Man” and “Bat Girl” (likely friends of our Ninja) along! Read her cool story here! (The story “Ninja goes South” is still on Flickr.com!)

Ice Man desperately needs to get to the Arctic – read the story by Ruth Mottram here! Photo: R. Mottram.

 

A76 – the largest iceberg in the world (at the moment)

My lunch out in the sun ended abruptly when my husband (also in home office) casually asked if I’d heard about the new iceberg in the Weddell Sea. If my husband – an economist – has heard about an iceberg it’s likely to be big… so I shuffled the rest of my pancake into my mouth and ran in to read!

And yes, a quick google revealed that a huge chunk (4320 km2, to be precise) of the Ronne ice-shelf has broken off! A76, as it is called, is now the largest iceberg floating around Antarctica – but (according to NewScientist) it would not make it onto the top ten of historical giant icebergs.

Will A76 end its days here, in the iceberg graveyard off South Orkney Islands?

It will be exciting to see where it drifts off to – and how it will influence the circulation on the continental shelf in the southern Weddell Sea. One of its old relatives, A23, that broke off from the neighboring Filchner ice-shelf in 1986, is still (!) stranded on the continental shelf, affecting e.g. the sea-ice distribution in the region.

 

The southern Weddell Sea with the location of A76 (not to scale) and the old A23. Modified from Ryan et al, 2017.

New adventure, new website! www.elindarelius.no

I’m now counting the days of what seems like an eternal quarantine, locked up alone in a hotel room in Bremerhafen, Germany. All alone – almost… Don’t tell anyone, but I’ve brought Mr. Ninja along, and he will join me when we fly off to Port Stanely and Polarstern in just over ten days! (Apparently the longest Lufthansa flight ever!) From Stanely, we will head south to the Weddell Sea, and hopefully recover the moorings we deployed in 2017.

Mr. Ninja has previously been with Dr. Petra Langebroek to EastGRIP and Greenland – read about their adventures here!

If you’ve signed up to get e-mail alerts about new blog posts on the old website, you have to sign up again (to the right)! Sorry about that!

(and MANY thanks to Mirjam for helping me move!)