All maps lie

When you think of a map, I guess north is up, south is down, east is right and west is left, right? Did you know this is just one way of making a map? And did you know that no map can accurately represent the whole world?

The problem with maps is that they to try to represent something that is three-dimensional and round (the Earth) on a flat surface. Try to peel and orange, and make the peel flat, without creating any gaps. It’s not possible! That is why there are hundreds of map projections, and none of them are 100 % accurate!

The “standard” map (that we are most used to seeing) uses the Mercator projection. The Mercator preserves direction, but not size. The good thing is that locations which lie north-south and east-west of each other is correctly placed on the map relative to each other. This makes it good for navigation, which is why i.e. Google Maps use it. But look at how much bigger Mercator makes Greenland look, compared to Africa:

 

Mercator vs actual

Size of Greenland and Africa in a Mercator map vs in reality. The real size of Greenland is actually only about 1/14 of the size of Africa. (Source: Reddit, u/Asuros)

On a Mercator map, the farther north/south you go, the more things are stretched out. Why? The Earth is round, so the circumference of the Earth, parallel to the equator, decrease the farther north/south you go from the equator (the thickest part). So on the top and bottom of these maps, the map have to stretch out much more (left-right) the Earth to make the north/south lines correct.

And if you go far north/south, almost to the poles (which are really just one small point), they have to stretch along the whole edge of the map:

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Mercator, you’re of no use for me anymore up here.

The Mercator is used a lot because it’s useful for navigation, the errors are small when you use it for navigation on a small scale (like in cities), and it is usually not a big problem because very few people ever go this far north or south and need directions on Google Maps. But sometimes you need to make maps of the Arctic or Antarctic regions, though.

Enter the polar stereographic map projection, where the north/south pole are in the middle! This means that at one latitude, all distances are correct, and the further away you move, the more distortion you get.

When I first saw these maps, it took some time to get used to. But now, I think they are beautiful!

Topography and bathymetry map of the Arctic region

Topography (height of landscape) and bathymetry (depth of ocean) of the Arctic region in a polar stereographic projection. [1]

[1] Petrov O, Smelror M,  Morozov A,  Shokalsky S, Kashubin S, M Artemieva I,  E Moore T, Grantz A, Grikurov G, Sobolev N, Petrov E and Ernst R. (2015). Crustal structure and tectonic model of the Arctic region (TeMAr). Earth-Science Reviews. 154. 10.1016/j.earscirev.2015.06.008

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Seismic in the Arctic: Sound can help you see below the ice and the seabed

This post was originally written while I was on the Arctic Ocean 2016 research cruise, but was never published. But hey – it’s Thursday, so why not throw a little #ThrowbackThursday post, and learn something new about seismics?

An important part of the Arctic Ocean 2016 research cruise have been to collect seismic data (more about the reason behind the cruise here). Seismic collection reveals the velocities in the sediments and the structure of the Earth’s crust. The velocities in the sediments are used to document the thickness of and types of sediments. Thus, these results can give new knowledge about the tectonic history of the Arctic!

Seismic surveys are principally made by making a loud bang underwater and recording the sound that comes back. We tow all seismic equipment behind the ship with what is called an umbilical cord (see photos below from a deployment). The air gun that makes the sound is closest to the ship and is towed between 12 to 20 metres below the surface. A streamer is attached behind the air gun, which floats 3 to 10 metres below the surface. The streamer contains hydrophones (underwater microphones) that listen to the reflected and refracted sound from the air gun.

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Deployment of the seismic equipment from the aft deck

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The air gun, before going in the water

When seismic surveys are done in open water, you usually have kilometres of streamers towing behind the ship. Longer streamers gives a larger picture of the sound image, both in time and space. This gives more information to the scientists about the deeper and older layers. When sailing in the ice, it is not possible to have long streamers because of the ice. Therefore we only have 200 metres of streamer, which is really short in a seismic setting. In order to get a better sound picture, buoys with hydrophones are deployed far away to listen to the sound. This serves the function as an artificially prolonged streamer:

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A schematic of seismic refraction (courtesy: Thomas Funck)

Some buoys are deployed directly in the water. They sink, and cannot be recovered. Other listening stations are deployed on the ice with helicopter, and are retrieved after some time, like in the photo below.

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Deploying a listening bouy on the ice (photo courtesy: Thomas Funck)

As I wrote in the post about icebreaking, we were sailing in straight lines due to the seismic lines (but sailing in straight lines is not easy while breaking ice!). The sound signals are recorded in the time domain, which means that in stead of seeing where the signal came from you only know when it came back. To convert this to the spatial domain (to be able to place it on a map), you have to calculate with the speed of sound and do some other calculations. Therefore, the calculations are easier if the signals are recorded along a straight line. Thus, for the most part of the research cruise, we have been breaking a nice, straight line through the ice for the LSSL, while they have been shooting seismic in our wake. However, after we split ways we have done several seismic lines by ourselves. Due to ice conditions, we actually had to first sail along the line and break the ice, then sail back, deploy the seismic equipment and sail the line again. It was a lot of back and forth, but it makes a really nice “broken highway”:

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Broken, Arctic highway; sailing in our own tracks when doing seismics

The sub-surface air gun fires around every 12 seconds. The bang is loud, and you can hear it well all over the ship. It is worst for the people with cabins in the annex, furthest to the aft of the ship. In our cabin on the second deck, the bang is not very prominent. On the bridge, however, you can actually feel the vibrations in your body, in addition to hearing the bang. But you get used to it after a while, and then, when it stops, it suddenly feels like something is wrong.

To minimize the impact of the loud noise on animals, we have a dedicated “mammal observer” on board. When doing seismic, Dale is on the lookout for whales and polar bears in the water. If one is observed, we stop the shooting immediately. Fortunately, we have not seen any mammals while shooting seismic this time. Or maybe I should say unfortunately? After 41 days in the Arctic we still have not seen a single polar bear!

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Seismic results, with some markings on it (courtesy: Thomas Funck)

(Thanks to Thomas Funck and Anders Dahlin for fact checking, providing photos and helping me learn about seismics!)

Science and identity: Your name is everything

In scientific writing, standard convention is referring to a scientist by last name and/or initial of their first name. So let’s say you want to cite a paper I’ve written, you cite it in the text as Skarbø (year) (given that the paper has author-year referencing style, my favourite), or in the references as Skarbø, R.A. + year, name of paper, publication, etc…

As you get to know a topic, you start recognizing names and citations of authorities in that field. After a while, you many times don’t need to look in the reference list to know which paper the author is referring to, you know the article only by the citation.

Thus, as a scientist, your name is your identify and your everything. However, this can yield some problems.

What if your name is very common? Imagine searching for the author “J Smith“, or “J Wang“, which both gives 100+ hits on Google Scholar author search. In a big research field, how will you know which one is the one you want? In nanoscience alone, there are more than 1,200 “J Wang”‘s!

What if you change your name? Back in the days, most scientists were men, and women were the ones changing their names when marrying, so this was not really a big problem. But these days, scientists are both men and women, and both may change their name when marrying. What if author “H Olsen” goes to being “H Olsen-Solvang” or “H Solvang” after marrying — how will you know it’s the same person?

Fortunately, some clever people have thought of this. Just like research papers can have unique digital identifiers, known as a DOIs, researchers can have the same. An ORCID is a permanent digital identifier for researchers.  By associating it with all you publish, you avoid all the name troubles above, and more. If you want to know what it looks like, here is mine.

The people over at Impactstory has written a great summary of more of the benefits of using ORCID. You should check out the post, and of course register to get an ORCID if you’re a researcher! (It literally takes 30 seconds — easier than signing up for Facebook).

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My face when problems are solved and the weather is nice

#MusicMonday: I’ll be your icebreaker

I don’t know of many songs about ice management, but Norway’s ESC contribution from 2016, Icebreaker, comes pretty close. Ok, so maybe the lyrics are not meant to be taken that literally, but for me it’s almost hard not to!

Do you know the song? Or any other songs about ice management?

Lyrics

Every night
Before I sleep a shiver down my spine
Thoughts align
What can I do to make you listen

Like a northern light
You’re dancing over every border line
Passing every sign
Between reality and fiction

Every single promise that you ever made
Spinning in my mind like a hurricane
Baby, yes, I hear your mayday

I’ll be your icebreaker 
When you’re stuck in frozen water 
(When you’re stuck in) 
Frozen water 

You go astray
Just like a Polaroid
You fade away
I’ll be you partner
and liberate you from your prison

Baby, yes, I hear your mayday

We’re way too young to say goodbye
Whenever you loose faith just hold the line
It takes a lot of nerve to save a life

#TBT: Visiting Svalbard for the first time

Two years ago, I visited Svalbard and the Arctic for the first time. I had started my PhD just a couple of months before, and given my topic, we knew I would spend some time in field in the Arctic and on Svalbard.

Safety is crucial when spending time in these remote and harsh places, so with my colleagues Martina and Andrei, I went to Svalbard to attend a one-week safety course at UNIS.

Another post is coming up about the safety course, stay tuned!

Follow Maren to Antarctica

Maren, a master’s students in our group, is going to Antarctica in just a few weeks! She will blog about her experience during the journey. Read more about what her work here, and make sure to follow if you are interested to see what a field expedition to Antarctica looks like!

Why Antarctica? — Three weeks in Antarctica

Leker Antarktis i kjelleren på Gløs om dagen ❄⛄🤘 #iceicebaby

A post shared by Maren Salte Kallelid (@marenkallelid) on

First sea trials in ice completed

After three days of sailing, we arrived in the Gulf of Bothnia on Saturday afternoon. This northernmost sea between Sweden and Finland freeze over in winter, and this is where we will conduct the sea trials.

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Ice in the Bothnian Bay.

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Sunset meeting on the bridge.

We are performing sea trials in ice with two offshore anchor handling tug supply (AHTS) vessels. Magne Viking, the vessel I am on, has ice class but is not an icebreaker. This means it can sail and break ice in light ice conditions, due to its reinforced hull. The other vessel, Tor Viking, is an actual icebreaking AHTS. So we send that one in front when we are sailing to break the ice.

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New offshore adventures: SKT2017

Hey guys! I am writing to you from a ship again! The next three weeks I will spend offshore on vessel Magne Viking, an anchor handler with ice class. We are part of what is going to be sea trials in ice with two ships in the Bothnian Bay, north in the Baltic Sea. Joining us is the vessel Tor Viking, an anchor handling vessel that is also an icebreaker.

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Tor Viking and Magne Viking at berth in Landskrona during mobilization.

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New promo video for NTNU, and I’m in it!

Some days my job is more amazing than others. Today, I and all other employees and students at NTNU received an email from the rector Gunnar Bovim launching the new promo video for the university. They have been collecting videos from NTNU people all through the year for this. When we went to the North Pole, I got an email asking us to do a video on the North Pole to use in the video. And not only did they use our clip in the video, rector Bovim chose a still from our clip in the email AND mentioned me by name along side Nobel laureate Edvard Moser.

I’m overwhelmed! I know it’s not a huge thing (I mean, the Moser’s won the Nobel Prize and all, I just sat on a boat going to the North Pole), but even still I was a bit floored, knowing the email went out to over 40.000 people. Bear with me.

I think the video is really good and well made, and it makes me proud to study and work in NTNU.

Can you spot me?

Hint: There is a clip from the North Pole at 1:45.

Best moments of 2016

Gledelig jul and Merry Christmas! I hope everyone has had a peaceful Christmas, and stuffed their faces with all the good food and candy that belongs in this holiday. My Christmas was spent in Oslo (my home town) with my family; my mother, sister, her girlfriend and their dogs. Even though there was no white Cristmas this year, at least we had sun!

Some of you have messaged me and asked if I have quit blogging, since there has not been much activity recently. The answer is definitely no! I enjoy writing, and I get to do so many awesome things during this PhD journey that I love to share with you. In 2017, one of my new year’s resolutions will be to blog more frequently!

2016 has been a great year for me. During this first year of my PhD, I have learned and experienced so much. I wanted to do a recap post of all these moments, but I may do separate posts on some of the highlights later. Some of them definitely deserve that!

The moments and experiences are impossible to rate, so I will just list them in chronological order:

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