Tag Archives: ship

The nice (and dedicated) people of N-ICE

Imagine this scenario: you’re stuck on a boat in the Arctic Ocean in the middle of the night. The winds are howling, the air is frigid, and the boat you’re in is completely encased in ice. Step off the boat and your face is constantly sand-blasted by tiny ice particles. Blink at the wrong time and your eyes freeze shut. The ice may crack under your feet (or between you and the boat)  – without notice – leaving icy water between you and the only warm place for hundreds of kilometers. Have to swim for it? Look out for jellyfish. Decide to stay on your crumbling patch of ice? I hear polar bears can get pretty hungry. Death awaits every misstep and every wrong turn. Cowering in the boat? Internet access is limited, there are no re-runs of Friends to keep you entertained, and the shuffleboard court is outside. (Actually, it’s worse than that: there is no shuffleboard court!)

Now imagine this: you actually wanted to be there!

Most people would say, “That’s crazy! I would never do that!” But, for the scientists and crew aboard the research vessel (RV) Lance, it is a unique opportunity to further our understanding of the Arctic and its role in the Earth’s climate system.

You see, we are nearing the mid-point of the N-ICE 2015 field experiment, which is taking place from 1 January to 1 August 2015. The idea behind the experiment is to take a boat, freeze it in the Arctic ice sheet, and constantly monitor the environment around the boat for about six months. A group of scientists work in six-week shifts where they monitor everything from the weather to local biology. Of course, the primary objective is to see what happens with the ice itself.

One of our very own researchers at CIRA (and one of the world’s leading experts on snow) was on board during the first leg of the experiment.  So, what is a snow expert doing on a ship whose primary purpose is to study ice?

Here’s the lowdown. There are two types of ice that concern Arctic researchers: “young” and “multi-year”. As the name implies, multi-year ice is ice that survives the summer and lasts for more than one year. Young ice does not reach its first birthday – it melts over the summer. Arctic researchers have been finding out that, not only is the Arctic ice sheet shrinking, it’s lost most of its multi-year ice, which is being replaced by young ice.

Multi-year ice is thicker, more resilient and tends to be brighter (more reflective), while young ice is thinner, darker (less reflective of sunlight), and less resilient. The less sunlight that is reflected, the more sunlight is absorbed into the system and this leads to warming, which melts more ice (and is a positive feedback). The less ice there is, the more open ocean there is, and open water is a lot less reflective than ice, which leads to more absorption of sunlight, more warming, more melting, etc.

The thinner “young ice” breaks up more easily due to wind and waves. This creates more leads of open water. The water, being much warmer than the air above it, pumps heat and moisture into the atmosphere, creating more clouds and snow – just like lake-effect or sea-effect snow. And, while most people have a hard time believing it, snow is a good insulator. Snow on top of the ice will create a blanket that protects the ice from the really cold air above. This reduces the rate at which the ice thickens up, keeping the ice thinner, and we have another positive feedback.

That’s just one of the things being studied on the 2015 Norwegian Young Sea Ice Cruise. Of course, I wouldn’t be mentioning any of this unless VIIRS could provide information to help out with the mission.

Go back to the N-ICE 2015 website. Notice the sliding bar/calendar on the bottom of the map. You can use that to follow the progress of the ship. Or, you can use the VIIRS Day/Night Band.

At the time of this writing, the Lance is docked in Longyearbyen, the largest town on the island of Spitsbergen in Norway. (Spitsbergen is part of the Svalbard archipelago, which has a direct connection to VIIRS. Svalbard has a receiving station used by NOAA that collects and distributes data from nearly all of their polar-orbiting satellites.) Longyearbyen is where the RV Lance and Norwegian icebreaker KV Svalbard departed for the Arctic back in mid-January. KV Svalbard escorted the RV Lance into the ice sheet, then returned to Longyearbyen while the Lance froze itself into the ice. See if you can see that in this loop of VIIRS Day/Night Band images from 12 – 17 January 2015:

Animation of VIIRS Day/Night Band images from 12-17 January 2015

Animation of VIIRS Day/Night Band images from 12-17 January 2015. These images cover the area of the N-ICE field experiment, north of Svalbard.

Notice how the one bright light follows a lead in the ice until it stops. Then the light appears to split in two, with one light source heading back the way it came and the other stuck in the ice. That is the start of N-ICE 2015!  The KV Svalbard did its duty. If you look closely, there are also some other boats hanging out in the open water near the edge of the ice sheet during this time.

If you suspect there are jumps in the images you’re right. VIIRS passes over this area every day 6-8 times between 00 and 12 UTC, with no overpasses for the next 12 hours.

Toward the end of January you can see how the RV Lance drifted to the west along with the ice:

Animation of VIIRS Day/Night Band images from 23-30 January 2015

Animation of VIIRS Day/Night Band images from 23-30 January 2015. These images cover the area of the N-ICE field experiment, north of Svalbard.

This was all according to plan. But, then, in February, the winds shifted and helped the ice spit the boat back out towards the open water:

Animation of VIIRS Day/Night Band images from 8-15 February 2015

Animation of VIIRS Day/Night Band images from 8-15 February 2015. These images show the area of the N-ICE field experiment, north of Svalbard.

After this, the RV Lance needed help from the KV Svalbard to be repositioned in the ice sheet near where it started a month earlier. Otherwise, all the instruments they placed in the ice would no longer be in the ice – they’d be at the bottom of the ocean as the ice sheet broke up all around them.

If you want to know why the ship seems to disappear and reappear every day, you can thank the sun. You see, the first few weeks of the experiment took place during the long polar night. But, by mid-February, twilight began to encroach on the domain during the afternoons. This was enough light to drown out the light from the ship. (Sunrise occurred in early March.)

Another thing to notice with these last two animations: the cloud streets that form over the open water near Svalbard. The direction these cloud streets move gives a pretty good indicator of where the ice is going to go, since both the clouds and icebergs are being pushed and pulled by the same wind.

It’s fascinating to watch the movement of the ice over the first 6 weeks of the field experiment. To save on file size and downloading time, the animation below only uses one image per day (between 10 and 11 UTC). Here’s 6 weeks of images in 5 seconds:

Animation of VIIRS Day/Night Band images from 11 January to 28 February 2015

Animation of VIIRS Day/Night Band images from 11 January to 28 February 2015. These images show the area of the N-ICE field experiment, north of Svalbard.

And you probably thought of sea ice as being relatively static.

Once again, we lose sight of the RV Lance because of afternoon twilight in mid-February, so we can’t see it or the KV Svalbard after that. And note that there’s a lot less open water near Svalbard by the end of the period.

What if we didn’t have the Day/Night Band? You wouldn’t be able to see the ships at all, that’s for sure! Plus, this area was under darkness (no direct sunlight) for this six week period, so none of the other visible wavelength channels will work.  That leaves us with the infrared (IR), which looks like this:

Animation of VIIRS IR (M-15) images from 11 January to 28 February 2015

Animation of VIIRS IR (M-15) images from 11 January to 28 February 2015. These images cover the area of the N-ICE field experiment, north of Svalbard.

Note that clouds appear to have a greater impact on the detection of ice (and distinction between ice and clouds) in the IR. When it’s relatively cloud-free, there is enough of a temperature contrast between the open water and ice to see the icebergs but, pretty much any cloud will obscure the ice. So, why doesn’t the Day/Night Band have this problem?

That has to do with the optical properties of clouds at visible and IR wavelengths. Most of these clouds are optically thick in the IR and optically thin in the visible. The Day/Night Band can see through these clouds (most of them, anyway) while channels like M-15 (10.7 µm) shown here, can’t. We’ve seen more extreme examples of this before.

In the rapidly changing Arctic, it is nice to know that there are a few dedicated individuals who risk frostbite, hypothermia and polar bears to provide valuable information on how the ice impacts the environment both locally and globally. Me: I’ll just stick to analyzing satellite data from my nice, comfortable office, thank you.

By the way, the N-ICE field experiment has it’s own blog, and pictures and other snippets of information about the people and progress of the mission are regularly posted to Instagram, Facebook and Twitter.

Santa Claus and the Olympic Flame

In the lead up to the 2014 Winter Olympics, the Olympic Torch was sent on a grueling journey across Russia and beyond – including a trip to the North Pole and to Outer Space. (Obviously, the torch won’t be lit when it is in space. You don’t want to burn up all the oxygen on the International Space Station – the astronauts need that to breathe. It also wouldn’t burn during the space walk, since there is no air out there.) An offshoot of the flame did make it to the North Pole, though, which is the first time that has ever happened. One could argue that it wasn’t really the true Olympic Flame, since the original flame burned out during a jog around the Kremlin in Moscow:

But, I’m sure the backup cigarette lighter is a valid substitute for having to jog all the way back to Athens, Greece to get the high priestess of the Temple of Hera to invoke the power of the sun to relight it. (We poke fun in good nature, knowing full well that it could happen to any of us – any of us lucky enough to carry the torch.)

Now, back to the Olympic Flame’s trip to the North Pole. Under the cover of clouds, the nuclear-powered icebreaker, 50 Years of Victory (50 лет Победы in Russian), carried the flame to the furthest north it could go. Once there, the torchbearers gave Santa Claus quite the light show. Check out the videos and photos of the trip – it was pretty impressive. Santa was grateful for the presentation. It was his last opportunity to take a break before finishing his Christmas preparations.

So, what does this have to do with a blog about a weather satellite? VIIRS saw the Olympic Flame and the Star Wars-like light show put on at the North Pole.

According to those news articles, the ship arrived at the North Pole on 19 October 2013. Below is an animation images from the Day/Night Band for every VIIRS overpass from 01:38 UTC on 19 October to 06:23 UTC on 20 October 2013.

Animation of VIIRS Day/Night Band images from 19-20 October 2013

Animation of VIIRS Day/Night Band images from 19-20 October 2013. The North Pole is located at the center of the image. Light from the ship carrying the 2014 Winter Olympic torch is visible.

The yellow dotted lines are latitude and longitude lines. The longitude lines converge on the North Pole. Initially, there is an opaque cloud layer that obscures the view of the 50 Years of Victory, but by the 08:23 UTC 19 October 2013 frame, the light from the ship is clearly visible. In the last two frames, the icebreaker can be seen heading back to Russia, which is off the top of the image. (Canada and the United States are below the bottom edge of the image.)

Keep in mind, since we are past the Autumnal Equinox, it is always night at the North Pole. That’s why we can see the ship’s lights. (It would be too bright to see the ship if it were daylight.) That also means that Santa has to finish making presents for everyone in the dark.

And, sorry kids. The Day/Night Band does not have high-enough resolution to be able to see Santa’s house. But, it does have high-enough resolution to see an icebreaker ship at work.


UPDATE/ASIDE: William Straka III (U. of Wisconsin/CIMSS) has done some investigating of ships at night in the Arctic using the Day/Night Band, and has shared these images (converted to a single animation):

Animation of selected VIIRS Day/Night Band images from 30 October to 2 November 2013

Animation of selected VIIRS Day/Night Band images from 30 October to 2 November 2013. Images courtesy William Straka III (CIMSS).

This animation covers several days (30 October to 2 November 2013) where a couple of icebreaker ships are visible. Using the website sailwx.info, he was able to identify one of the ships as the icebreaker Taimyr (Таймыр). Here’s a plot of the ship’s track over this period:

Plot of the track of the Russian icebreaker Taimyr, 30 October to 4 November 2013

Plot of the track of the Russian icebreaker Taimyr, 30 October to 4 November 2013. Image courtesy sailwx.info and William Straka III (CIMSS).

The other ship (or ships, since there seem to be two areas of light in some of the images) are unidentified. He was able to deduce the following:

One of the ships in “Group 1” is an icebreaker. (It has to be, because there is ice covering the ocean in this region.) That icebreaker cannot be the 50 Years of Victory (50 лет Победы), since it had returned to port following its trip to the North Pole. Tracking information from sailwx.info also shows that it was not the Vaygach (Вайгач). News reports show that the Rossiya (Россия) was retired from service in May 2013. The only other nuclear-powered icebreakers in the Russian fleet are the Yamal (Яма́л) and the Sovetskiy Soyuz (Советский Союз). (Of course, there is the possibility that the icebreaker isn’t nuclear-powered, which increases the number of possibilities.)

In case you’re interested, this scene takes place near the New Siberian Islands. I’m not sure what kind of services they have on the islands but, judging by the images above, they look like a good place to view the aurora!