Science | Mallemaroking – Part 3

by maximios • North Pole

In the previous post I made a plot of Antarctica and compared it to the size of Europe. I made the throwaway point that it was unreasonable to imagine Antarctica as being characterized with one climatic zone. It is not all the “coldest and windiest place” on Earth.

I thought a simple example would show what I mean:

I got the mean monthly temperatures at two Antarctic Stations from the NOAA NCDC GCPS MONTHLY STATION data available from IRI/LDEO Climate Data Library.

I chose Adelaide Island and Vostok, and picked monthly data from December 1964 to December 1966.

The mean monthly temperature at Adelaide Island and Vostok station

Adelaide island is on the coast and it astonishingly beautiful. The data I used were collected at the British Antarctic Survey BASE T.

In contrast Vostok station is quite literally an icy waste in the middle of nowhere (* but see below).

This plot shows their relative locations in relation to the South Pole.

The locations of Adelaide Island, Vostok, and South Pole

You can see that at Adelaide Island – which is at sea level and coastal – the seasonal cycle is relatively narrow and only about 11°C. Temperatures are above 0°C in the summer.

At Vostok – which is on the East Antarctic Ice Sheet and at an altitude of about 3700m – the seasonal cycle is vast. In the Antarctic summer the temperatures are about -30°C, whereas in winter the temperatures fall and it is scarily cold (monthly mean -71.4°C in August 1966!).

If you want to know why Adelaide Island has a relatively small seasonal cycle, whereas Vostok seems to have a squashed “U” shape temperature cycle, then you have to understand something about the basic meteorology of the Antarctic Regions. (As an aside then you would understand why this happens in winter).

In a later post I may say something about how the climate is changing across Antarctica over the last 50-60 years. The spoiler on that is at on the Antarctic Peninsula it has changed a lot – in the range “4-5°C”,and the changes are impacting the ocean system, whereas at Vostok it has not.

* – of course Vostok isn’t really in the middle of “nowhere”. It is over the vast and hugely significant under ice Lake Vostok, and is the location of the first great Antarctic ice core – the Vostok Ice Core.

I keep seeing a map of Antarctica with an overlaid outline of the United States. I thought it would be helpful to have a picture of the continent compared with the size of Europe.

Antarctica compared with the size of Europe

This is a picture from a book I wrote half of and edited a long time ago.

It always struck me as strange that Antarctica being the “coldest and windiest place” is constantly recycled. The picture shows it is a huge place and it does not have one single climate.

On the Antarctic Peninsula it is relatively mild. It’s even referred to sometimes as being the “banana belt”. But away from the heat of the ocean, and high on the plateau it is without doubt cold almost beyond comprehension.

But one thing is for sure: there is no representative Antarctic climate.

I don’t usually work on this sort of thing, but very recently I have been writing about hazards caused by the cryosphere. A major hazard is of course the avalanche – whether ice, snow, or a mixture.

This video was posted on You tube (with the tag line “Courtesy Vertical Solutions”), and it shows the impact of a snow and ice avalanche on the Alaskan road network on the 26 January 2014.

I tweeted it yesterday and the glaciologist Mauri Pelto replied

@icey_mark That is Richardson Highway that is flooded now, if this releases as one would expect in a torrent, the highway will fair worse.

— Mauri Pelto (@realglacier) January 27, 2014

I’ll try to remember to keep an eye online to see the outcome.

I came across this brilliant Deep Sea News blog post about oil on troubled waters. It talks at length about how a surface film of oil damps out higher frequency surface waves and only the low frequency waves can propagate. The net effect is the sea feels calmer as the breaking waves are damped out.

The same thing happens in rough seas when ice forms. I took the picture below in Bellingshausen Sea.

A grease ice slick in the Bellingshausen Sea Antarctica

What you are looking at is very thin slick made up of sea ice crystals in the open ocean (called grease ice). The layer of crystals only allows the low frequency waves to propagate – so you see these odd looking slowly propagating ripples.

This is a storify of the twitter noise around one talk at a Royal Society discussion meeting.

This is a storify of a discussion meeting at the Royal Society.

Working on the sea ice of the Bellingshausen Sea

Whilst wandering around various old textbooks I came across a wonderful quote:

Polar ice cannot be studied as other branches of science, philosophy, medicine or law are studied. The study of sea ice belongs among the most exhausting disciplines which have to be studied on the spot, in loco status nascendi et vitae, and which require strong men, absolutely sound in mind and body, courageous, willing and fit to renounce all comfort, thoroughly prepared both in theory for the work and ready to face all the hardships that may come like a bolt from the blue and in the most unfavourable moments. The sea-ice has to be studied far away, in the north or south, in white deserts of ice, where there is nothing, nothing else, no shelter no help; and where, on those vast plains in which the chasms of the sea keep tearing open and unsurmountable obstacles in the shape of mountains of ice keep piling up, the Lord only is with man.

“and as long as man will listen to the roar of the waves above the depth of the the sea, as long as the human eye will follow the play of the northern light on the silent snowy landscapes, and far away in infinite space, and so long as it will look out for the celestial bodies far away in infinite space, so long the romance of the Unknown will lead the human genius forward and upward!” (Nansen, Nebelheim.)

It is a quote from the beginning of Cryologia Maris by Josef Zukriegel, which was published in 1935 by the Geographical Institute of the Charles IV. University.

All of what Zukriegel says is all true of course – except naturally lots of women do sea ice research as well. In fact if you look at the latest AR5 IPCC report, and chapter 4 which is on the cryosphere, you will see many brilliant women polar scientists in the reference list.

Josef is a bit hard to track down for a Brit, but he does have an island named after him in Antarctica. If you look at the extremely useful gazetteer of the UK Antarctic Place names committee you can see it is actually in quite a hard place to get too.

This post is quite long but stay with it. It shows how large some of the heat exchanges going on in the polar oceans can be.

The picture above shows an iceberg through mist rising from the sea.

It is pretty, but it is also showing is a vast heat flux of hundreds of watts per m² from the ocean to the atmosphere…

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I have talked before on this blog about how the sea ice moves, and how the International Arctic Buoy Programme provide some lovely movies of the buoy tracks which show this. I also pointed to Eric Larsen’s video of the ice moving too.

But what does this ice movement mean for the climate?

As the ice moves it fractures, and the cracks extend over wide areas. These cracks are responsible for the “water sky” I talked about previously.

A recent MODIS satellite image from the Aqua satellite posted at the NASA earth Observatory shows one of these cracks (we call them leads) opening up.

A modis image showing a lead and sea smoke in the Arctic Ocean May 2013. From the NASA EO

From the scale bar on the bottom left you can see that the open water is ~18 km wide, and the lead is more than 100 km long. More than enough to get a ship through!

In March 2013 I was delighted to be asked to give a talk at TEDx Southampton.

This is what I talked about: What the poles are telling us about our world

It was brilliant to be asked to speak, and really enjoyed the fantastically well organized day. Many thanks to the hardworking large team who put it together, and in particularly James Dyke,Alison Simmance and Jonathan Akass.

On the TEDx Southampton YouTube channel for the event are some amazing talks from that day.