Falling ApartâŠ
Iâm writing this from a hotel room in Ilulissat, rather than Qaanaaq where I had intended to be arriving shortly, because our plane has been cancelled due to bad weather (at time of writing the airport was measuring gusts of 14 m/s, so Iâm actually quite glad it was cancelled).
Weather and flight cancellations are an eternal hazard when doing fieldwork in Greenland, but in this case it also means an impact on our planned fieldwork, because the sea ice is falling apart. And rather earlier than usual (though we have not yet done a systematic review to prove this). In fact, part of the reason for coming here in May (instead of my usual March trip) was to investigate an interesting event that happened earlier this spring. In the animation of satellite pictures below you can see the sea ice rather dramatically falling apart in mid-April and then again at the end of April.
The March to May sea ice season from Sentinel 2 in NW Greenland
To understand what is happening and why itâs unusual, first a bit of background. As I have written before, my DMI colleagues have been working up in NW Greenland for about 15 years on a programme of ocean measurements in the fjord (see map below). I joined about 5 years ago, working in the melange zone of the glaciers at the head of Inglefield Bredning (PSA: a paper we recently submitted about this programme will hopefully be online soon). We use the sea ice as highway and stable platform for observations, so itâs pretty important for us and came to the conclusion it wa squite important for some parts of the glaciers too. The local community, with whom we work closely use it also for travelling, hunting and fishing from. Itâs extremely important for them.
The region of North West Greenland weâre talking about
Normally thereâs pretty thick (~1m) sea ice covering the whole of Inglefield Bredning (Gulf of Inglefield, also known as Kangerlussuaq, but not that one) out to the islands of Qeqertarsuaq and Kiatak. You can seen an example of what this looks like normally in the satellite animation from 2020, which happens to be when my first trip out on to the sea ice in Qaanaaq took place at the end of May and beginning of June. We were actually very lucky, we had great weather, got very close to the ice edge and watched narwhals swimming out in the North Water polynya. (Yes, sometimes I wonder how I managed to get this job too). The animation below is Sentinel-2 images as cloud free as I could find them from that first field season. As you can see, the sea ice already in March was much much more extensive than this year at the same time. And perhaps that is part of the answer.
Itâs probably worth pointing out at this stage that although there were some pretty warm (unusually so) spikes in March and April, the sea ice breakup in April was probably largely driven by ocean swell, and perhaps some winds which were strong, though not excessively so as far as we can see in the observations. The latest break-up seems to be driven also by high winds.
Back to our current field season. We had in fact planned a brief trip up here already â I am currently setting up a project looking at snow processes with the team and we had planned to install and test some new instruments and protocol that we hope to use in Antarctica later this year (more on all of that later hopefully). However, as the soon to be published preprint shows, I and the team have developed pretty extensive sea ice interests recently, so this unusual behaviour rather piqued our curiosity.
We have a lot of questions:
Why did it happen this year? Is it really the earliest in the satellite record? What makes the ice vulnerable? Composition, thickness, temperature? Is the ocean driving it or the atmosphere or both (itâs usually both), and what makes this year so unusual? Further down the line, can we model it and use those simulations to understand if this is a single aberration or likely to be more common in the future? And what impact will the earlier breakups have on the ecosystem, the adjacent glaciers and the local community?
Or fieldtrip thus appeared an excellent opportunity to grab some real data on all of these points. Our colleague Henriette Skourup at DTU-Space was kind enough to lend us one of her instruments, which we shipped up last minute to allow us to do an add-on. It is all currently sitting there waiting for us.
Unfortunately the sea ice is not waiting for us, if the photos from my colleague in Qaanaaq, Aksel are anything to go by.
A large and widening crack in the sea ice in front of Qaanaaq. The small objects on the sea ice (fishing gear?) suggest we were not the only ones surprised). Credit: Aksel Ascanius, DMI
The high winds which grounded our plane have also been busy on the sea ice, which is falling apart in the bay with surprising speed as far as I can see. We are still waiting for todayâs optical imagery but the quick look from radar based Sentinel-1 suggests cracks widening rapidly as the photo above confirms.
Temperature observations from Qaanaaq airport
With a bit of luck we will get to Qaanaaq on Thursday (immaqa) to see if our sea ice research plan can go ahead. At this stage I rather doubt it. But it will very much depend on the next few hours. The wind speeds are quite high still but the temperature which was well above freezing has now dropped down to just below.
Wind observations from Qaanaaq airport
We are fortunate that we work with local hunters on the sea ice who are immensely experienced. The first rule is always safety first. We do have *a lot* of other work to do and rather fewer days to do it all in, so either way weâll be busy. Ffor now, itâs keep checking in with the weather, the satellite images and our friends in Qaanaaq and use the time in Ilulissat wisely â in our case, itâs time to write some papers. And one of them is all about sea ice.
To be continuedâŠ
All satellite imagery on this page is from the European Space Agency Sentinel-2 mission, processed on the Copernicus EO Browser â a FREE!! and easy to use entry point to use ESA data. Weather observations are from Qaanaaq airport, operated by Mittarfeqarfiit A/S â GrĂžnlands Lufthavne (Greenland Airports) and processed by DMI. Itâs actually pretty nice how much high quality data we have access to these daysâŠ
This fieldwork is undertaken as part of the PRECISE (Predicting Ice Sheets on Earth) project funded by the Novo Nordisk Foundation and by the ESA Climate Change Initiative for Sea Ice and the Climate Modelling Research Group
#Arctic #fieldwork #Greenland #Qaanaaq #satelliteData #Science #SeaIce
Ruth Mottram
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Ruth Mottram 
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