Exploring the new Arctic Ocean by Donald Perovich

Exploring the new Arctic Ocean by Donald Perovich


– Good afternoon. Welcome, everyone. My name is Lauren Culler, and I’m a faculty member
in environmental studies and at Dartmouth’s
Institute of Arctic Studies. And I have the honor today to introduce our speaker, Dr. Don Perovich. Dr. Perovich is a professor at the Thayer School of Engineering. He’s an incredibly accomplished,
internationally recognized sea ice expert and geophysicist. Dr. Perovich is the co-lead
for sea ice research on this MOSAiC Project, which probably many of
you have heard about. MOSAiC is the Multidisciplinary
drifting Observatory for the Study of Arctic Climate. In fact, I read an
article that described it as the largest polar
expedition in history. It involves over 600
international partners from 17 different countries, and actually just started
a little over a week ago. The goal of this is to have scientists on a vessel that gets locked in the sea
ice floe for an entire year, making important observations
of Arctic climate, probably a lot of what we’ll
be hearing about today. So, Dr. Perovich, in addition to being a sea
ice expert and geophysicist is also a really gifted educator
and science communicator. I first met Dr. Perovich in
a course here at Dartmouth called Intro to Polar Systems when he explained to a very interdisciplinary group of students the technicalities of
his sea ice research, really helping us understand
some of the key concepts like ice-albedo feedback, and also weaving into it his rules for working in the Arctic, some of which we may hear about today. And if not, we should bring that up during the question and answer period. I just want to mention also that after today’s seminar,
immediately following, there’s a reception upstairs
in the Dickey Center, and everyone is invited
to come up, join us, and continue the conversations with Dr. Perovich about sea ice. So, I’d like to turn
it over to Dr. Perovich to give his talk, In the
Drift Track of Nansen: Exploring the New Arctic Ocean. (audience applauding) – The Arctic Ocean is a harsh environment. Months of unrelenting darkness,
bitter cold temperatures, high winds, blowing snow, shifting ice. Trust me, it’s a harsh environment. The Arctic Ocean is frozen. It’s so cold in the Arctic that the ocean freezes, forming sea ice. The sea ice cover’s vast in areal extent, covering millions of square kilometers. But it’s just a thin veneer of
ice, only a few meters thick. And since it’s floating, it moves. Driven by winds and by currents, it can easily move kilometers per day. And we can look at it and see
it’s bright and it’s white. It’s highly reflective. The Arctic Ocean is
also a place of dreams, a place that’s always
captured our imagination. And it’s a place of dreams now, and it was a place of dreams long ago, more than a century ago in the 1800s, where the Arctic grabbed
people’s imagination with dreams of the unknown. Questions of what lies in
the heart of the Arctic, no one knew. Was there a continent there? Were there islands? What was it like? Was there an open ocean beyond the ice? And that motivated many explorers. You’ve probably heard of some of them, explorers like Franklin
and the lost expedition. There were many expeditions,
and so much suffering. And just looking at one
of those expeditions, it was the voyage of the Jeannette. It was the first major U.S.
Navy Arctic expedition. They sent out with a goal
to get to the North Pole by going up through the
Bering Strait into the Arctic. In September of 1879, they were frozen into the
pack near Wrangel Island. They didn’t know it at the time, but that was really a bad place to be. There was a lot of ice
activity, and the ice broke up. And they drifted for a
year, a year and a half, until June of 1881 when the ship was crushed in the ice. At that point, they tried
to make it to safety. There were 33 people. They had some lifeboats. Of those 33, only 13 survive. The rest were lost at sea, or starved once they reached land. So that’s the voyage of the Jeannette. It was similar to a lot of
the other early explorations. But there was one more thing about it. And that’s years later, in June of 1884, three years later, wreckage from the Jeannette was found in the ice off the
southern tip of Greenland. People wondered how it got there. And one person in particular,
Henrik Mohn, had a theory. Mohn was a very respected scientist. He was an astronomer and meteorologist. In fact, he founded the
Norwegian Meteorological Society. And his theory was
there must be a current. There must be a large-scale
current from east to west that brought the ice down and brought the wreckage of the Jeannette. Well, as I said, he was very respected, but nobody was buying this idea because at the time, the belief was the Arctic Ocean was shallow. Because it was certainly
shallow around the edges. And if it was shallow, there
must be a lot of islands. And if it’s shallow with a lot of islands, there can’t be a major
current such as that. So, in general, he wasn’t
really listened to, with one notable exception. A young, recently graduated PhD listened intently and had an idea. And that was Fridtjof Nansen. Nansen was a neuroscientist. That’s how he got his PhD. He was also a polar explorer, and had recently done the
first crossing of Greenland, and an oceanographer. Much later in his life,
he became a diplomat, a humanitarian, and a Nobel laureate. Now, if people were
skeptical of Mohn’s theory, they totally didn’t believe
that Nansen could do this. Even though they respected
his accomplishments, the idea was, this is crazy. But they did say, well, we’ve learned a lot about the Arctic. And Nansen’s very diligent, he can learn from that knowledge. We’ve learned that we take an
existing vessel and refit it. And we never, ever get trapped in the ice because when you do, bad things happen. And if we can navigate through the ice, we can get to the open polar ocean. And take lots of people, because you’re going to have
some casualties along the way. And Nansen looked at
that and considered it, and decided to reject every single item. Decided this was all wrong. And he came up with a new paradigm. Rather than refitting an existing ship, he was going to build his
own ship from scratch, designed to be in the ice. He planned on getting trapped in the ice and then drift to the pole, and then out through the North Atlantic, just like the wreckage from the Jeannette. And take a small team, a small team of well-trained men that were used to working in the Arctic. And learn from the Inuit. After his crossing of Greenland he spent several months Inuk waiting for his trip home. And he thought, well, this
will only take a few years, or maybe four or five, but don’t worry until seven or eight. And it was an audacious plan. Well, that was the nicest
thing you could say, was audacious. Some thought it was an
outrageous and insane plan. Now, the key to this was a ship. And that led to the polar ship Fram. In Norwegian, fram means forward, which is a very apt name for this ship. It was a totally new ship design. It was based on a three-masted schooner which was double-ended. That means the stern had
the same shape as the bow. You can see it in the diagram here. It was unusually wide and shallow. It was squat. It was 39 meters long, and 11 meters wide, and it only had a draft of five meters. It had a rounded hull with nothing to grip. You can see it in the cross sections. In fact, the naval architect
that designed it, Archer, said the design was such, “To slip like an eel from
the embrace of the ice.” the idea was when the ice
pressures inevitably came, rather than crushing the ship it would just pop it up on the ice. Now, it still had to be strong enough to withstand some forces, and so they had a hull
thickness, on average, was two feet four inches thick. And at the bow and the stern it was even further reinforced with four feet of wood. And it had a crew of only 13. And this shows the drift of the Fram. It took Nansen a couple years
to organize the expedition, to get funding for it,
to have the ship built. And so, they were ready
to leave in July of 1893. They left civilization, as it were, in Vardo, Norway, on the 21st of July. And from that point on, there was no communication with anybody. They voyaged up the
northern coast of Russia, and this was not an easy trip. This was literally a voyage
between a rock and a hard place. It was in shallow waters
and on one side was land and on the other side was
the encroaching ice cover. But they finally made it to
where they wanted to start. They were frozen into the ice in the 22nd of September, 1893, and they drifted for a year, then a year and a half. And finally, Nansen realized
that while they were drifting kind of what the way they expected to, they were going to miss the pole. So he decided to have
a mad dash to the pole with one other person, Johansen. They got their skis on, and
they headed off to the pole. Now, when you’re skiing on the ice, how much progress you make really depends on what the conditions are. If you’re lucky, you can cover maybe 10 or 20 kilometers a day. The ice could move 10 or
20 kilometers per day. And if it’s moving the same
way you’re going, that’s great. If it’s moving in the other
direction, it’s not so good. And finally, after a month of doing this Nansen realized they weren’t
going to make it to the pole, and if they wanted to survive they had to start heading back so they could reach land before
the summer melted the ice. They did reach 86 north,
which was the furthest north that anyone had ever reached. They did make it to land, and started working their way back. The Fram continued drifting, and it drifted for a few more years. And on the 13th of August, 1896, it was released from the ice. And incredibly, around the same time Nansen was making his way back to Norway. He had hitched a ride on a ship. There was a giant rendezvous
on the 21st of August in Tromso, where Nansen
and the Fram were reunited, and they worked their way
down the coast to Oslo where they arrived on the 9th of September to a celebration that was the
biggest in Norwegian history. This was an incredible expedition three years across the Arctic. Now, they learned a lot
from this expedition. They learned indeed there
was a drift pattern. And the drift was close
to what they expected. Another thing they learned was, while the Arctic Ocean was
shallow around the edges, it was really deep in the middle. It was so deep they
didn’t have enough chain to measure how deep it was. They learned that the Fram worked. When the pressures got great, the ship was popped up on the ice. And they gained weight. They showed that a small
team, well supplied, could also live off the
land and do just fine. Now, this was mainly
motivated by exploration, but it was more than that. Nansen was a scientist, and science was really important. And this expedition produced six volumes of scientific findings with information on
magnetism, meteorology, oceanography, and sea ice. It was just an incredible voyage where they learned so much, not just about geography
but about science as well. The Arctic was in their dreams. And even today, the Arctic
is still in our dreams. Slightly different dreams. Now we have dreams of
present and future climates. Maybe dream is the wrong word. Sometimes it feels like
we’re having nightmares of present and future climates. And what’s shown here are two maps. Not a map with blank spaces, but maps of temperature. Temperatures in the past,
the present, and the future. In this plot on the left we
see the change in temperature over time from 1960 to 2010, where it goes from the north pole, through the equator,
down to the south pole. And these are observations. These are observations
that we’ve made over time. And what you can see in early years it’s a little bit warm in one place, a little bit cold somewhere else. But in recent decades,
the picture’s changed. There’s more of these yellows
and oranges that show warming. And when you look at it, we see the greatest warming
has happened in the Arctic where we’ve observed temperature increases of a few degrees centigrade
just in the past two decades. On the right we see a map of
not what is, but what might be. It’s a map using climate models to look ahead to the year 2090 and see what the
temperature change would be under business as usual. And here you see everywhere you look there’s oranges and reds. Everywhere you look on
Earth, there are increases. But it’s important to note that the deepest reds and the purples, the largest increases in temperature, occur in the Arctic. And that leads us to another
attribute of the Arctic. The Arctic Ocean is fragile. Sea ice is a material that’s always close to its melting point. And it’s very sensitive
to changes in temperature. And we can use that. We can use Arctic sea ice as a proxy for changes in temperature. It’s an indicator of climate change. If you think about it,
if it’s getting colder we would expect there
to be more and more ice. It’s this large, thin veneer, and if it’s warmer we would expect there to be less and less ice. So we can use the ice as an
indicator of climate change. And we’re fortunate because,
for the past 40 years, we’ve had satellites looking
down at the ice cover, day and night, good weather, bad weather, detecting where there’s ice, and where there’s open ocean. And from that, we have a 40-year record of what the extent of the ice cover is. And we can look at that record, and we see this plot. Basically, on the vertical
axis is the ice extent in millions of square kilometers. On the horizontal axis it’s time, from 1979 up until the present. We now have a 40-year record of this. And each dot represents a month. And you look at this, and
you see there are these wild oscillations, almost
by a factor of two. And you’re thinking, wow, we’ve
got some good science here. This is going to be a great finding. Well, it’s the seasons. And people have already
discovered the seasons so we’re not going to
get famous out of this. But it does make our point that we can use sea ice
as a detector of change. Because in the winter it’s cold and the amount of ice goes way up, and in the summer it’s warm and the amount of ice goes down. This plot also illustrates
a problem that we have trying to detect a climate change signal. Because what we have are
large seasonal variations and variations from year to year. How do we tease out a relatively
small climate change signal from those larger variations? In the case of sea ice extent we do it by throwing away a lot of data. Instead of looking at every month, we’re just going to look at one
month, and that’s September, because September is the end of summer when the ice reaches its minimum value. And that’s when we’d be able to detect a change in climate the easiest. And when we do that, we get this plot. Again, same kind of plot, the ice extent over time. And the first thing you notice about this, there are a lot of changes. Things go up and down, they
bounce around from year to year. Here in 1995 we had the lowest we had ever recorded to that point. In ’96, we had the
largest we ever recorded. So there is this large
year-to-year variability. But if you look at this you can also see there’s a general downward trend. And we can look at that more closely just by fitting the best
straight line we can through it. And that’s what’s shown here. When we do a linear fit to this data we see there’s a decrease
of 13% per decade that we’ve seen over
the past four decades. Now, when it comes to sea
ice and climate change this is truly the iconic graph. This has been looked at
in incredible detail. We’ve fit different curves to
it, polynomials, exponentials. We’ve broken it up into little pieces. We stared at it like so many tea leaves. And people have come up with
different conclusions from it, but the main thing is, no matter how you look at
it, there’s a decrease. And I have to confess, I’ve spent quite a bit
of time looking at this, trying different things with it. And what I think is most telling is this graph right here. In 2007 we had the largest
decrease in ice extent that we ever saw from
September to September. It was the biggest
decrease, and at the time, it set the all-time record minimum. Since then, there have
been some ups, some downs. There was a new record set in 2012. But the key point is we’ve never gotten back
to the pre-2007 levels. That basically we’ve entered
into a new Arctic regime. This was a fundamental change in the nature of the ice cover. Now, these graphs are good. They’re numbers, they’re
nice and quantitative. They give us an idea of what’s going on. We can apply some math to it. But it’s also good to get
more of a feel for it, what these changes look like,
and where they’re changing. What I’m going to show now
is an animation from NASA. And a couple things to look at. It shows two things. It shows the extent of the ice, and it also shows a quantity
called the age of the ice. Now, sea ice compared to
glacier ice is really young. It can be only a few months old if it just formed that year, or it can be up to four or five years old. And what’s shown in the colors, you can see the scale here,
is the age of the ice. The ice in white is
four to five years old. And that’s important
because generally speaking the older ice is, the thicker it is. And the thicker it is,
the more resilient it is. And that resilient ice can
make it through a warm summer and smooths out the oscillations
in the climate system. And so you can see here there’s a large amount. Up here it actually tells you how much of this old ice there is. Back when this started in January of ’84 there’s around 2.5
million square kilometers. So we’re going to go through. And one of the things I like about it, it’s almost as though
the ice is breathing. It kind of inhales and
gets bigger in the winter, and exhales and shrinks
down in the summer. And you can see that annual
cycle, the ice moving around. If you look at it, the
old ice comes out here along the east coast of Greenland through a region called the Fram Strait. And yes, it’s named after the same Fram. But we see as we go through we still have this large amount of this older, thicker, multi-year ice. It extends in the winter,
retreats in the summer. And that’s pretty much a solid unit. Sometimes it’s round, sometimes
it gets stretched out, and that’s mainly due to what the atmospheric pressure
patterns are, and the winds. Now as we get into the
’90s, into the 2000s, you start to see some differences. There’s some younger ice
mixed in with the older ice. We’re still outputting it here. And the ice in this
area tends to go around, and circles and get older and older. As we get closer to 2007 watch this area. And so into 2008, and if you look at it, now we have streamers of
ice going into this region and not making it out. Just melting in place in the summer. As we come up to 2012 it’s
another record minimum. And now there’s just small
strings of this multi-year ice. It’s down under half a
million square kilometers. And the old ice is now being
more or less restricted to just being off the coast
of the Canadian Archipelago. So that’s just a visualization of how much things have
changed over the years. Let’s take a look at a couple snapshots to see it in more detail. This is the way it looked
in September of 1984 when we had quite a bit of the old ice in here, over 2.5 million square kilometers of it. And we had the graveyard. Ice was exported off the Fram Strait. But we also had a nursery
in the Beaufort Gyre where the ice would just go around and get older and older. We jump ahead to 2012 and now we’ve got two graveyards. The ice that flows into
this area in the summer completely melts. So it’s a large change. And one of the difficulties is putting these changes in perspective. I mean, looking at it helps some. And sometimes you’ll hear,
well, climate’s always changing. There are always variations. Maybe this is just a fluctuation. So it’s good to try to
put it into some context. In September of 1980, the ice cover was roughly 7.8
million square kilometers. In 2012 it was reduced to
3.4 million square kilometers for a loss of 4.4 million
square kilometers. Now, that’s a bunch of numbers, and the numbers are really too big to have much of an understanding of, so let’s try to put it
into a different context. It turned out that back in the 1980s the ice cover was around the size of the continental United States. So we can just ask ourselves the question, between the 1980s and 2012, how much of the United States has melted? And that’s how much. The entire U.S. east of
the Mississippi has melted. The band of states from Minnesota
down to Louisiana melted. North Dakota, South Dakota, Nebraska, Kansas, and Oklahoma, all melted. This isn’t a fluctuation. This is a major change. And so we’ve taken a look at
what’s happened to the sea ice. But being people, we always
want to know what’s next. We want to know what’s going
to happen next in the story. And so for that we turn to climate models. And climate models are
interested in Arctic sea ice. And what you see here is a familiar plot, ice extent in the vertical axis and time on the horizontal axis. Only now, the timescale
isn’t a few decades. It’s two centuries, starting back in 1900 going up to 2100. This is the accumulation of results from a number of different climate models. The solid blue line represents
the average of those models. Kind of the blue band shows
the range of those models. And orange shows our observations. And there’s a couple key
points from this plot. The first one is, reality’s happening
faster than the models. We’re seeing losses at a more
rapid rate than are predicted. And the second is, the models
have quite a bit of spread that only gets bigger as
we go into the future. Now, the models, if we look at 2100 we have a range of outcomes to we could have more ice than we have now, or we can not have any ice at all. That’s not really a
very satisfying answer. And if you talk to the modeling community they explain that there’s many processes that just aren’t being treated properly in these large-scale climate models. And that the reason they’re
not being treated properly is there aren’t enough observations. That we need observations
to improve our treatment of these different processes. So we have a system that’s
undergoing tremendous changes. We’ve entered into a new Arctic. The modeling community says
we need more observation. And that’s the motivation for MOSAiC. The Multidisciplinary drifting Observatory for the Study of Arctic Climate. It’s a yearlong drift experiment that started on September 20th with the ships leaving Tromso, Norway, and will continue to October of 2020. The centerpiece of MOSAiC is the German icebreaker Polarstern which will go into the ice,
be frozen into the ice, with a camp next to it, and
drift for the next year. MOSAiC is guided by an
overarching science question What are the causes and consequences of an evolving and diminished
Arctic sea ice cover? And under that overarching question there are five sub-questions. What affects the heat and
momentum balances of sea ice? How does first year sea
ice move and deform? What processes contribute
to clouds and precipitation? And what are the cycles of
ecosystems and biogeochemistry? And how are these ongoing changes impacting the Arctic system? MOSAiC is about
understanding the new Arctic which has less ice, and younger ice. So let’s take a minute and
do MOSAiC by the numbers. It’s the biggest sea ice experiment ever. It’s highly interdisciplinary,
and it’s international. MOSAiC has undergone 10 years of planning. There are 19 nations involved. It’s going to take five
icebreakers to do it. Right now, the bill is at 150 million, and the costs haven’t
stopped coming in yet. It’s involving 600 experts. Scientists who will either be in the field or working back home. The overall duration of
the expedition is 390 days. And of those days, 150 of them
will be in total darkness. And the expected drift is around 250… Or 2,500 kilometers. Now, if you’re doing a big
drift experiment like this the first challenge is where to start. And that’s what’s happening right now. I checked on the website
before coming over. They’re looking for a floe. Basically, we’re shopping for a house. And if you’re shopping
for a house for a year, the first thing you want to do is decide what neighborhood you want to live in, where you want to start. And we worked on that quite a bit. We decided we wanted to
start from the Laptev Sea, north of Russia. But we wanted to stay out of the Russian Exclusive Economic Zone because we can’t take measurements there. And we wanted to come out the Fram Strait, but not too soon, but not too late. And to take a look at this, we
ran hundreds of simulations. Thomas Krumpen at the
Alfred Wegener Institute ran hundreds of simulations using the best ice drift models available, also taking data from satellites and from autonomous buoys to come up with the odds, the odds of drifting far enough north, or drifting into the Russian EEZ, and what’s the survival rate. Not necessarily that the
floe is going to break up, but that whole area would
be nothing but water. And we used this to inform
where we would start. And again, Nansen just had
somebody’s fanciful idea that there was an overall drift, and we have all this information. Now, once you decide on the neighborhood the next thing is what
do you want for a house, what floe do you want. Well, you want a floe that’s
at least two years old. You want a floe that’s big enough, more than a kilometer and a half across. And you want it to be thick enough, more than a meter and a half thick. And you want to be close to the ice edge because we want to get this mix of old ice and young ice in open water. But you don’t want to be
too close to the ice edge because wave action could
come in and break the floe up. And you want to be in a place where the drift forecasts are favorable. We’re really looking for
a Goldilocks floe here. Now, after all those calculations
and all the discussions what’s seen here is the
projected start point and the drift of the Polarstern. It’s color coded by month. Here we are in October of this year, going through the whole year, and coming out the Fram
Strait October of next year. This is the hypothetical drift pattern. And if you look at that, it
should seem vaguely familiar. Or maybe not even vaguely familiar. There’s Nansen’s drift of the Fram. We’re basically going in
the drift track of the fram. Now, there are a couple
notable differences. We’re starting much further north. And the reason for that is there’s not ice anymore in
September where the Fram started. We have to go significantly
further north to find ice. And we also expect that our
drift will only take a year, partly because we’re
starting further north, but also partly because this
younger, thinner ice pack moves a lot faster than the old one did. Now, the Fram left, was on
its own for three years. We’re doing things a little
bit differently in MOSAiC. MOSAiC will have six legs. The first leg is three months because it involves setting things up. But in general, the legs
are two months long. And there will be rotations
done mainly by icebreaker. And right now there are
two ships heading north, the Polarstern, which
will be the drift ship, and the Russian icebreaker Fedorov which will help deploy things and gas up the Fedorov
before returning home. The rotation between legs one and two will be done by a Russian
icebreaker, the Admiral Makarov, and it will also do the next
rotation between two and three. Leg four, the plan is to do it by aircraft because at that point it will be April, we’ll be near the pole, and in the dead of winter when the ice is at its maximum extent we didn’t feel that we could
get an icebreaker up there, so that will be done by aircraft. And then in spring, the
Swedish icebreaker Oden will do a rotation. And then at the end of summer, the Chinese icebreaker Xue
Long will do a rotation. So you’ve got five
icebreakers involved in this. They’ll be resupplying things. They’ll be swapping out science teams. There are so many people that
wanted to participate in this, but only so many berths,
so the way it was resolved by rotating people in and out. There’s also an opportunity. The Polarstern needs to
be gassed up periodically, so these resupplies will
bring in fuel for the ship. And it’s also a chance to bring
in food and other supplies. And from a scientific perspective it’s an opportunity to
extend the spatial scale. While those ships are moving people will be making observations, weather balloons will be launched, we’ll be doing an ice watch to look at what the ice conditions are. MOSAiC is interested in spatial scales. This is an incredible opportunity, and we want to be sure we get it right. There is what we call
the central observatory. It’s basically the ship, and around the ice, around
five kilometers out. You can think of it as
how far you can walk. And that will be the area where the intense observations are made. We’ll be setting up instruments. We’ll be doing things that
you need a person to do. Beyond that, there’s
the distributed network. This goes out to an area
of roughly 50 kilometers. It’s designed to be the size of a grid cell in a climate model. And here we’ll make observations with autonomous instrumentation that makes some of the measurements that we’ll be making at
the central observatory. And there will also be aircraft
and helicopter flights. And finally there’s the large-scale. This is a scale of
thousands of kilometers. The resupply ships will
look at this scale. There will be long-range aircraft flights, and we’ll information from satellites. And this is also something
that will be useful for climate models. And that’s one of the really interesting things about MOSAiC. It’s really been unlike any experiment that I’ve been involved with because since the very
first day of planning it was both the modeling
and the observing community getting together to design the experiment. That basically we sat down and the modeling community said, here are the things that
we don’t understand well. Let’s come up with a
way to make measurements so we can improve our
understanding of those items. And so, really, we’ve
designed a virtuous cycle where we have models
informing observations to improve models. MOSAiC has five teams. Atmosphere, sea ice, ocean,
ecosystems, and biogeochemistry. And each of those teams
has been meeting together to define what measurements
they want to make, what their science questions are, how they’re going to do things. And even more importantly, they’ve been working with each
other to find common areas where we can get synergy
between these groups. For example, if we take sunlight, the atmospheric scientists are interested in how sunlight interacts with clouds. From an ice perspective we’re interested on how the sunlight is partitioned. The ecosystem people want
to know how much light reaches the ocean for
primary productivity. And the biogeochemists have photochemical processes
they’re interested in. So it’s really an
interdisciplinary effort. So let’s take a quick look through some of these different elements to see what we’re going
to be doing up there. For the atmosphere, it’s
clouds, clouds, and clouds. If you talk to anyone, they’ll say, we don’t treat clouds in
Arctic models well enough. For that matter, we don’t treat clouds in climate models well enough. So there will be intensive study of clouds using ship-based cloud
radars and cloud LIDARs. There will also be aircraft overflights. There will be studies of aerosols. And then there’s also an
interest in precipitation. How much snow do we get in the winter? Do we have rain events in the summer, or do we even have rain
events in the winter? And of course there’s interest in what’s going on in the boundary layer in terms of temperature,
humidity, and wind speed. And there’ll be a tower that’s
profiling those properties. There’ll also be balloon
launches looking at that all the way up through the
atmosphere, four a day. And the results from
those balloon launches will be incorporated
into weather forecasts. And we’re also interested in
the surface energy budget. How much heat comes in,
how much heat goes out? The ocean. In some ways, there’s some
similarities with the atmosphere. The atmosphere has a tower,
the ocean has a mast. Going down, looking at
profiles of temperature, salinity, and currents. There’ll also be studies looking at turbulence at the ice-ocean interface and how much heat goes from
the ocean into the ice. There’ll also be studies looking at leads. Leads are areas where
the ice is broken apart and there’s open ocean. We’ll be studying, in the winter, how heat is lost from the leads, and in the summer, how heat
is entrained in the leads. We’ll also be deep casting the
ocean for sampling purposes. Rosettes, bottles will go down. These things are called Nansen bottles. And yeah, it’s the same Nansen. Biogeochemists are really excited because it’s a chance to look at sunrise. You have photochemical processes in an area where it’s dark
for several months on end. And then the sun rises,
and things start to happen. And typically, it’s very hard to get up in the ice pack at sunrise unless you’re already there. And for MOSAiC, we’ll already be there. So, they’ll be looking at carbon, sulfur, nitrogen, and halogen. And they’ll mainly be doing this through sampling techniques, sampling of the air, of
the ice, and the ocean. And they’re also interested
in the amount of sunlight and how that changes over
the course of the year. And then there’s ecosystem studies. Their main excitement is winter. For years, the thought was, well, we don’t have to study winter
because nothing happens then. But it was really more like,
well, since we’re not there, nothing’s happening, right? So this is an incredible opportunity to really see what’s going on in winter and to observe the
changing ice ocean habitat. Now, the ecosystem
studies are mainly focused on the bottom part of the food web, looking at ice algae,
phytoplankton, and copepods. And they’ll be looking
at nutrients and light, and trying to understand both the carbon and nitrogen cycles. And looking at particle fluxes. And the way they’ll be doing this is they’ll be taking samples
from those Nansen bottles. They’ll also be doing net tows to get samples of what’s in the ocean. And they’re going to be
doing some ice core sampling. They’ll be taking, over
the course of MOSAiC, probably 2,000 or 3,000 ice cores to look at what’s going on
at the bottom of the ice. And then there’s sea ice. We’re going to take a little bit more time to talk about sea ice because that’s the most exciting part. It’s also the part that
our team’s involved with. There are seven of us on the project. Four of us are from Thayer. We also have two collaborators from the University of Washington and one from the National
Center for Atmospheric Research. We’re looking at the ice. We want to look at the
components of the ice. We want to see how it varies spatially and what its temporal evolution is. And again, just like MOSAiC as a whole, our observation plan is motivated
by the modeling community. Our modeler is Marika Holland at NCAR. She’s told us what some of the holes and gaps in the models are. And one of them is snow. Just a simple question is,
how much snow is there? And how does it vary spatially, and how does it vary over time? And then to look at more details, what are the grain size of
the snow, the grain type? What’s the density of the snow cover? What’s the stratigraphy? And most importantly, what’s
its thermal conductivity? And we have devices to measure snow depth. We can measure thousands
of snow depths in a day. We’ll have temperature strings looking at temperature
profiles in the snow cover. And we also, onboard the ship, have devices to look
at computer tomography where we can take samples,
take them back to the ship, and look at the very detailed
structure of the snow. We’re also looking at sea ice morphology. What’s the surface topography of the ice? How thick is it? And then what are some of the properties? How big are the floes? What are the melt ponds like? And what melt ponds are, in summer, the snow melts and the
surface of the ice melts and some of that melt water collects, forming these melt ponds. And they’re very interesting
because they have an impact on the freshwater balance, and also on how sunlight is distributed. And we’ll look at ridges, places where the ice crunches together. And again, looking at these leads. How do they freeze in the winter, and how do they enhance
melt in the summer? And we have a number of
devices to look at this. We’ll be doing ice thickness surveys, both from the surface
and from helicopters. And we also now have a high
resolution surface-based LIDAR where we can get very
detailed maps of the surface. And we’ll be setting out areas
where we’ll map repeatedly so we can see the snow
build up in the winter, how it moves around during windstorms, and how the surface
melts during the summer. We’ll also look at the
sea ice mass balance. It’s my second most
favorite sea ice property. And all the mass balance is is how does the ice grow in the winter, and how does it melt in the summer? Mainly on the surface and the bottom, but also on the edges of the floes and in the interior of the floes. And for something this important we use highly sophisticated instruments, ablation stakes and thickness gauges, which are basically sticks and wires. They’re the same things people have been using for a century. But they’re inexpensive so
you can put out a lot of them. We’re going to put out
over 100 of these sites where we can measure the
changes in ice growth and also in terms of
surface and bottom melting throughout the whole year,
on a variety of ice types. And we’ll complement that with something a little bit more modern. The sea ice mass balance buoys that do the same thing as these thickness gauges
and ablation stakes, only they add some other
measurements such as temperature, and you don’t have to be there. They send it back via Iridium satellite. And we’ll be looking at my most favorite geophysical parameter, and that’s solar partitioning. We’re going to follow the photons and see where does all the sunshine go. We’re going to measure how
much sunlight comes in, what’s reflected from the
surface to the atmosphere, also known as the albedo, how much is absorbed in the ice, and how much is transmitted
into the upper ocean. Now, on the face of it,
that would be pretty easy, except for two things. One, the spatial variability you see, and two, the temporal variability as you go from spring to summer. And we’re going to take that
into account by doing surveys. We’re going to setup several survey lines, each a few hundred meters long, where we go along and we
measure those properties. We’ll also drill some
holes through the ice so we can put instruments down underneath to measure the amount of
light that’s transmitted. And we’re going to coordinate this effort with some of our German colleagues that have a remotely operated vehicle where they can do surveys
under the ice as well. We’re going to figure out where
does all of the sunlight go. We’re also interested in sea ice dynamics. We want to measure the
deformation of the ice. We know these ridges form. We also want to measure
the motion of the ice. How does it move on a large scale, and also on a smaller scale? And ultimately we want to understand the mechanical properties of the ice. What’s it’s rheology? And we’ll do that through a
number of different instruments. We’ll have stress sensors
that you embed in the ice and measure how much force
the ice is undergoing. And we can see how much
it takes to break the ice. We’ll also have an array of GPS buoys that are part of the distributed network. We’ll have 50 of these measuring very precisely
the changes in ice position. And one of the really exciting things is that we have a brand new LIDAR that can measure deformation
on very small scales so we can see how the ice
is deforming under pressure. And it’s even possible that
may give us an inclination if things are about to break up. So those are the five main things that the sea ice group is
going to be looking at. And if you have an experiment where you’ve got 19 nations,
five icebreakers, 600 people, you might expect it
takes some coordination. And indeed it does. We’ve spent a lot of time over the 10 years of planning, particularly the past few years, about figuring out how to coordinate this. And one of the examples is real estate. You’d think, we’re out
in the middle of nowhere, ice as far as you can
see in every direction, that why do you have to
worry about real estate. Well, you do, because it
gets used up really quickly. So we spent a lot of time
coming up with zoning laws. What you see here is our idealized map of what reality’s going to be like. And the grid, each grid
cell is 100 meters. This has the ship parked next to a nice, thick multi-year floe. And right next to it is
some younger, thinner ice. And what you see is there’s a power line that goes out through Ocean City out to Met City. Another power line that
goes out to an ROV area. Power line that goes
out to Remote Sensing. And when you’re in the 700 meter circle it’s the safe zone. From 9:00 to 5:00 every day you can work in that zone and not have to worry about polar bears because there’ll be polar bear guards patrolling that whole time. If you go beyond that,
there’s a whole other set of protocols you need to worry about. There are also wilderness areas where we’re going to try
to stay out of those areas and you can’t go into them
without permission from someone. So we’ve really spent a lot of time coordinating real estate. And we’ve also spent a lot of time coordinating what we’re going to do. Because nobody’s going
to be there all the time. In fact, if you look at most projects, they won’t even have people
there the whole time. Our project, we have Ian
Rafael on leg one now, and we also have people on
legs four, five, and six, but nobody on two and three. So somebody is going to
have to do our measurements. So we sat down as a team and decided what are the key things that we want to see happen the whole year, and how are we going to make
sure that they do happen. And so what we have, for every leg there’s
a schedule like this. And each team has a schedule for each leg. This is the sea ice schedule for leg five from the middle of June
to the middle of August, when I’m going to be up there. And there’s actually 14
people on the ice team, which is the most we’ll
ever have up on the ice. Summer’s really an interesting time. And you can see a breakdown. We have people assigned to cores. Monday is ice coring day. We go out with the biogeochemists
and the ecosystem folks, and we drill holes in
the ice all day long. There’s also time for
stakes, and transects, and the remotely operated
vehicle, and ponds. A couple other features in this schedule, you see this red area for basic. And what that is, those are
the basic things we have to do. Cleaning instruments, changing
batteries, things like that. Also, each day there’s a person
assigned to the helicopter, which in the summer usually means sitting around hoping
the fog will go away. But we do have a fairly
ambitious helicopter program of photography and surface LIDAR scanning. And there are these
green areas, flex time. Kind of a little bit of
flex in the schedule. The flex time serves a few purposes. One, there could be weather days. Particularly in the weather in the winter there are days where people
just aren’t going to be able to go out and work outside. And for the ice program, most of our program is out on the ice. So the flex days allow
you to shift things around to accommodate the weather. The second thing is,
while we’ve all agreed on some common measurements
that we all think are important, everybody kind of has their
own thing they want to do, and the flex time is an
opportunity to do that. And then finally we realized that MOSAiC isn’t a sprint, it’s a marathon. And you have to build in some time so people can just kick
back and take it easy. And the idea is, Sunday mornings,
that’s just take it off, maybe do some laundry,
read a book or something. So the flex time allows for that as well. Now, we’re all excited about MOSAiC. I think everybody has this vision of what they’re going to see,
what the results are going to be, the wonderful papers we’re going to write, the unexpected things
we’ve never dreamed of. But we all agree that
the data is the legacy. The data from MOSAiC, the
hope is that this will be used 20 or 30 years from now. And because of that, we
formalized a MOSAiC Data Policy. If you want to be part of MOSAiC you’ve got to sign this data policy. And it’s 12 pages long and basically says, yes, I’ll share, in great detail. So we’re working to promote
data fairness and accessibility. There’s a major focus on
observations to archive to get the data in a secure
archive as fast as possible. And with that in mind,
there’s two data scientists that will be onboard the Polarstern throughout the entire experiment to get things, at least the
preliminary data, archived. The ultimate goal is to
get a complete dataset that’s archived and published with all the explanations
of what that data is. There’s a really strong commitment to data sharing and archiving. When you look at it, MOSAiC
is a tremendous opportunity. It’s an opportunity to
spend a year on the ice, to study this young first-year ice, to perform process studies, to conduct interdisciplinary
research with the team, to take that knowledge and improve models, to give us a chance for
an improved understanding of the new Arctic. And we’re all really excited about it. And if you want to follow MOSAiC there’s a website that gives you… This website gives you
updates where it is. That’s where the ship
was as of 2:00 o’clock. It’s looking for a floe. And then there’s the more
general MOSAiC Expedition. We’ve been planning this for 10 years. It’s almost surreal that
it’s actually happening. But people are on the ship now, and they’re looking for a floe and getting ready to deploy things. And it’s really a very
exciting experience. But I want to make one last point, and that’s that it’s not just
an intellectual exercise. These changes in the Arctic
are having consequences today. They’re impacting coastal communities that without that sea
ice cover in the fall are exposed to coastal storms
and having enhanced erosion. There’s impacts on shipping as people start to look for shortcuts across the top of the world. There are geopolitical implications. Who owns the Arctic? It used to be an easy question, who cares. But now with the ice retreating and with surveys showing that over 20% of the undiscovered oil and gas is probably on those continental shelves, who owns the Arctic is now
a really important question. There’s also impacts on tourism. The Russian icebreaker 50 Years of Victory makes five round trips to
the north pole every summer, taking 120 tourists on the most powerful icebreaker in the world. It’s nuclear powered, it’s incredible. But at the same time, a cruise ship, the Crystal Serenity, did the Northwest Passage. It’s great that there
are these opportunities, but what if something goes wrong? There’s also impacts on ecosystems, impacts we really don’t understand. We don’t know what’s going
to be the consequences of changing the timing of algal blooms and phytoplankton blooms. And there’s a real
concern that the impacts will be strongly negative on the large mammals of the Arctic. And finally, there’s the issue of what happens in the Arctic
may not stay in the Arctic. There’s a lot of research going on now to investigate whether or
not there are connections to the changes that we’re
seeing in the Arctic and mid-latitude weather patterns. And this also motivates us for MOSAiC, that we know the
observations we are making hopefully will make a difference and have a beneficial impact on people. Thank you. (audience applauding) – [Moderator] We have
some time for questions, and we have microphones
that (speaking indistinctly) – [Participant] I can probably just shout. Oh. Well, I have about 20 questions,
but we’ll start with one. Is anyone suspecting or… It seemed from what you showed there is a Pacific to
Atlantic flow of water through the Arctic Ocean, up through the Bering Strait, ultimately then comes out down the coast of Greenland, right? – [Dr. Perovich] Not
necessarily the water. If you look at the large-scale pattern of ice drift, there’s a number of components. There’s the Beaufort Gyre, which kind of goes around
in a circle like this. And then there’s the Transpolar Drift that comes out that way. There’s water that comes in
through the Bering Strait, and by nature it’s fairly shallow because the Bering Strait is shallow. And that tends to branch off this way. And there’s also water that
comes in, deeper water, from the North Atlantic that comes in this way. There are these maps of ocean currents, and we could spend all day
trying to figure them out. – [Participant] Well, the
essence of my question… – [Dr. Perovich] So, the question. – [Participant] The essence
of my question really is is anyone suggesting that the changes in the polar ice
that are clearly happening may change really global
ocean circulation patterns, starting with those in the Arctic and then a kind of chain reaction through the rest of the ocean? – [Dr. Perovich] I think
for sea ice, I mean, it is a source of fresh
water when it melts. And I think, in general,
there’s always been interest… Let’s go back to… There’s always been the question of shutting down the circulation. And I think the consensus is that melting sea ice isn’t enough to do that. You have to have bad
things happen to Greenland to get enough fresh water. Do the Greenland people think that? – [Participant] Were there
any indigenous people involved in the planning, and are there any on the ship that are involved in doing the research? – [Dr. Perovich] I don’t know. I don’t know if there’s
any on the ship now. And I don’t know… There may have been a small
presence in the planning. I know for the work that I’ve
been involved with recently north of Alaska, like from the Healy, there’s always been
indigenous observers onboard. And also, we’ve always kind of gone around and informed the communities what we’re doing and
what we hoped to learn, and then got back to say,
here’s what we did learn. For this, I’m not so sure about it, maybe because it’s so far north. But I don’t know. I’ll check into that. – Have you used some of the
information you’ve gathered on the previous lock-ins? And how do you transpose or
apply it to this MOSAiC process? – [Dr. Perovich] Yeah, there’s… I mean, I was involved
with the SHEBA program, with was another yearlong
drift in ’97 and ’98, in a different neighborhood off of here. So there’s some things
that you can transfer. There was also a Norwegian
experiment over in this area. There was a six-month experiment. So I think there are logistic
things that you can transfer. There are scientific things, but one of the things scientifically
that’s been a challenge is a large part of the
motivation for MOSAiC is we’re in a new Arctic. So in terms of with SHEBA, when we were picking a floe one of the concerns was don’t
get something too thick. That’s not a problem with MOSAiC. So there are lessons
learned we can transfer but there’s a lot of big unknowns. Another big unknown is how
much snow we’re going to have. Over in this part of the Arctic, well, the old joke, at
least it’s my old joke, that for snow the answer is .3. The snow depth is .3 meters, the snow density is .3
grams per cubic centimeter, and the conductivity is .3. That may not apply over here. – [Participant] But you don’t
have that information, right? – Right, yeah. And that was part of the
reason to do it over there. Well, there are a couple
reasons to do it over there, and one was we hadn’t done a yearlong drift experiment over there. – [Participant] Is there any
data to show the difference in temperatures and in ice melts between the Arctic and Antarctica? – [Dr. Perovich] Yes. And if I drew that same kind
of plot for the Antarctic as this, it would look a lot different. In general, the Antarctic
went through a period where the sea ice cover was not declining, maybe increasing slightly overall. And now it’s reached a point where it’s starting to slightly decline. It does look a lot different. And I think that they’re aptly named. They’re the Arctic, and the anti-Arctic. You’ve got an ocean
surrounded by continents and then a continent surrounded by ocean. And in the Antarctic I
think that ocean boundary plays a much larger role. – You mentioned the
earlier SHEBA experiment. Could you just… Do you have an overview
as to what SHEBA didn’t do that you need to do now, and other contrasts between
the two experiments? – [Dr. Perovich] Sure. You probably don’t want to
get me started on SHEBA. But since it’s October
2nd, on October 2nd, 1997, the engines of the
Groseilliers were shut down, starting the drift of Ice Station SHEBA. A couple of the big differences is SHEBA, the focus was on understanding
the ice-albedo feedback and the cloud-radiation feedback, and then using that
understanding to improve models. Whereas MOSAiC, it’s to
determine what are the causes and consequences of an
ice-diminished Arctic. So the basic science
question is different. Another major difference is that SHEBA was focused on atmosphere, ice, and ocean. MOSAiC is also interested
in those three components but adds ecosystems and biogeochemistry, because we’ve really come
to realize that the… During SHEBA, we were just
beginning to understand the Arctic was a system. Well, we were beginning to understand it was a physical system. And now we understand
that that physical system is tightly connected to biogeochemistry and ecosystems as well. And then there are other
things like there’s… One of the things with
MOSAiC, for the clouds, there are techniques
now to look at aerosols that just didn’t exist during SHEBA. And some of these terrestrial
LIDARs we’ll be using to map the surface. There’s new tools as well. I will say that early on in
the ten years of planning it took some effort to
dissuade people that, oh, another SHEBA. But we finally did it. – [Moderator] One more
question in the back. – [Participant] Could you explain why the changes affecting Earth overall, they’re so much more extreme in the Arctic than in the Antarctic? – I’ll talk about the Arctic first. And that’s we have this
floating ice cover. And as I mentioned earlier,
it’s bright and it’s white. It’s highly reflective. But as that melts, it
exposes the dark ocean. And you get this ice-albedo feedback which in the bottles is
manifested as polar amplification. I think the difference in the Antarctic, and there are Antarctic people that could probably answer
this better than I can, is that you’ve got this
giant block of ice there that’s a couple miles high, and it’s going to take
a lot to change that. Does that sound right? – [Moderator] All right, well… – Okay, I have another thing to say, to respond to you, that we talked about the
three rules of the Arctic. (audience laughing) Rule number three was
never run, never sweat. Rule number two was
always have a ticket home. And rule number one, and
the most important rule, was eat as much as you
can, whenever you can. Which should segue into the reception. (audience laughing) (audience applauding)

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