For hundreds of years the Arctic has fascinated explorers who wonder
what treasures may lie under the massive ice plains that occupy much of
the territory.
FULL STORY
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THE DANGERS OF ICEBERGS
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FARMING RETURNS
Kangerlussuaq, Greenland (CNN) -- For hundreds of
years the Arctic has fascinated explorers and scientists who wonder what
treasures may lie under the massive ice plains that occupy much of the
territory here.
Uncovering the secrets of Greenland's ice
December 4, 2012 -- Updated 1406 GMT (2206 HKT)
STORY HIGHLIGHTS
- CNN correspondent joins scientists on mission to Greenland to understand how the vast ice sheet is changing
- Aerial radar missions and ice core drilling data helping build picture of past climate and helps predict future
- Melt layers point to extremely warm summers here in the recent years, according to scientists
- "We are doing an experiment with our planet and we have no idea what the outcome will be," says glaciologist
Adventurers from across
the globe have been coming to Greenland for years to try and uncover
what secrets lay beneath the massive ice shield here, which is more than
twice the size of the U.S. state of Texas. It turns out that many of
the riches are not hidden under the frozen and compressed snow layers,
but right in them.
Scientists gather a
wealth of information from the ice in Greenland. It gives of them
details on climates dating back more than 100,000 years, including
temperatures, precipitation, cloud cover, and special occurrences such
as volcanic eruptions that leave traces of ash.
"If we can understand the
past, then it will help us better predict the future of climate
change," says Trevor Popp, a climatologist from the University of Copenhagen.
"And Greenland is the
best place to experience the processes first hand. Someone once told me
this is where the rubber meets the road when it comes to studying
climate change."
"If we can understand the past, then it will help us better predict the future of climate change
Trevor Popp, University of Copenhagen
Trevor Popp, University of Copenhagen
An abundance of research
missions have been launched to the Arctic ice shield. One of the most
respected organizations working here is Germany's Alfred Wegener Institute for Polar and Marine Research.
The AWI as it is known as
has now given CNN the chance to participate in a mission to the Arctic,
featuring the institute's most advanced new research aircraft, Polar 6.
"It is a two-fold
mission," Daniel Steinhage the geophysicist who headed the endeavor told
us. "On the one hand we will fly radar survey missions over the ice to
penetrate the first hundred to two hundred meters. Then we will land in
some of the places along our flight route to drill shallow ice cores for
more exact results."
The mission's goal was
to develop an improved method to map the upper layers of Greenland's
Arctic ice, down to about 150 meters under the surface, in a bid to
improve climate projection models that try to tell us how temperatures,
rainfall and weather patterns on earth will evolve in the future.
The research seems
urgent after increases in severe weather like hurricanes have
increasingly raised the question of how global ice melt contributes to
these weather phenomena.
Greenland: Secrets in the Ice -- Part 1
Greenland: Secrets in the Ice -- Part 2
Greenland: Secrets in the Ice -- Part 3
Greenland: Secrets in the Ice -- Part 4
Greenland: Secrets in the Ice -- Part 5
Greenland: Secrets in the Ice -- Part 6
Sepp Kippstuhl, a
glaciologist at AWI says researchers are not sure how much humans
contribute to climate change, but that industrialization and the
emissions it creates surely have effects on climate.
"We turn on so many
screws that something somewhere has to change, but we don't know what
that change is or how severe it is. That is why we are trying to improve
our climate modeling," says Kippstuhl.
The AWI's mission to the
Arctic will try and improve methods of gaining data on ice melt in the
Arctic. After outfitting the Polar 6 research aircraft with antennas and
state of the art computer systems for over a week, the team and the
aircraft head to Kangerlussuaq in Greenland -- a former U.S. military
base that is home to about 600 people and the largest airfield on the
island.
Polar 6 is a unique
plane. The airframe comes from a DC-3 Dakota, a plane used by the U.S.
and other militaries in World War II and the following years to
transport goods. However, while Polar 6 might look like an old plane, it
is outfitted with state of the art modern avionics and brand new
engines, making it as reliable as any modern day aircraft.
The first part of the
AWI's polar mission was conducting radar survey flights to the middle of
Greenland's ice shield. After take off from Kangerlussuaq and a flight
over some of the most majestic fjords in the world, Polar 6 reached the
glaciers on the fringes of Greenland's inland ice. It took the aircraft
another two hours to get to the radar survey area.
The ice here is a lot
like the salt flats in Nevada, there are no hills or valley, no
landmarks whatsoever, making it extremely hard for the pilots to
distinguish the clouds from the surface.
"The extremes that we
operate in are really not something that can be taught," Polar 6's
captain Erik Bengtsson, a Canadian, told us while navigating the ice
plains.
"You need to just gain
experience flying in these conditions and you always have to keep an eye
on the weather because it changes so quickly out here."
Around three hours into our flight, Steinhage was finally able to boot his computers and start using the radar equipment.
"The radar penetrates
about 150 to 200 meters into the ice," Steinhage said, while monitoring a
variety of screens in the plane's hull. "The useful data goes about 100
to 120 meters deep, after that it is very distorted, but the data from
those depths is very useful."
The data gathered by
Polar 6's radars is part of the puzzle to try and map conditions in the
top layers of the arctic ice shield. The ice here consists of compressed
snow that fell in Greenland in the past and was then pressed into
layers as more and more precipitation came down over the years. The ice
is layered much like tree rings. Each layer represents a certain point
in time and gives clues to the climate conditions of that era.
"If we can understand
the past and get data from the past, then we can enter that information
into our computers and run it forward to try and predict how the climate
will change in the future," Steinhage said.
"The problem we have is
that every time we get new data there are also new questions as well.
There are so many factors influencing the world's climate that it is
very hard to predict how it will change in the future."
"We turn on so many screws that something somewhere has to change,
but we don't know what that change is or how severe it is. That is why
we are trying to improve our climate modeling
Sepp Kippstuhl, Alfred Wegener Institute
Sepp Kippstuhl, Alfred Wegener Institute
But each bit of information also delivers some answers to questions about the how our climate is evolving.
For the second part of
the AWI's missions, the team loaded a heavy drill into Polar 6's hull
and landed right in the middle of the ice shield on skis to drill ice
cores.
Delivering the drill
with a plane is unique in itself, so far researchers would mostly use
snow mobiles or other special vehicles to transport equipment to drill
sites. A process that could take days, with Polar 6 only takes a few
hours.
Sepp Kipfstuhl is in
charge of shallow ice core drilling at the AWI and brings more than 30
years of experience to the table. After a rough landing right on
Greenland's inland ice, Kipfstuhl and his team set up their drill and
begin working.
The cores they pull out
of the ice will have to be scientifically evaluated in a lab for months
after the end of the mission, but with his experience Kipfstuhl
immediately points to signs that point to very warm summers here in the
Arctic in the past years.
"On the ice you will see
melt layers," he says pointing to dark and very compressed layering in
the ice. "They are extremely prominent melt layers and guys who drilled
here 30 years ago say they don't remember melt layers this prominent.
The melt layers point to extremely warm summers here in the past years,
where the ice surface melted and then froze again during the winter."
That preliminary
evaluation is also backed by NASA data from its ice tracking satellite.
The space agency recorded unprecedented surface ice melt in the Arctic
this past summer with about 97% of Greenland's inland ice showing signs of thawing.
In normal years, about 50% of the ice shield's thaws. This process is
also clearly visible from the air as Polar 6 flies over Greenland. Clear
blue meltwater ponds dot the landscape, growing larger under the Arctic
summer's sun.
"We are doing an experiment with our planet and we have no idea
what the outcome will be, what the result will be. All we can do is try
to predict it
Sepp Kipfstuhl
Sepp Kipfstuhl
Kipfstuhl and his team
spent about seven hours drilling on the ice shield. All of the work
happens at night because during the day the thawing is so bad that the
ice surface becomes too slushy to operate a drill -- another sign that
temperatures are rising.
Like most scientists,
Kipfstuhl is not willing to speculate how much humans are contributing
to global warming. But he does say that humanity is taking a big risk.
"We are doing an
experiment with our planet and we have no idea what the outcome will be,
what the result will be. All we can do is try to predict it, but there
are so many variables in our environment that it is very hard," he said.
The debate on climate
change is extremely politically charged and it is hard to get unbiased
information. In a nutshell climate researchers will give the following
facts.
The earth is getting
warmer. Temperatures have increased dramatically since the industrial
revolution but it is still unclear how much humans are contributing to
global warming because there have been warmer and colder climate cycles
in the past. Warming temperatures and ice melt will lead to rising sea
levels and may be contributing to more frequent and more intense severe
weather on earth.
There is very little
certainty in today's climate research and missions like the one that the
Alfred-Wegener-Institute conducted in Greenland constantly try to
improve the available data to give a more accurate picture of what the
future might hold on this planet we inhabit. Their predictions become a
little more accurate with every expedition but every mission also brings
up new sets of questions that will take decades to answer.
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