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Greenland’s ice sheet

Reflections at the top of the world

It was 11:30 in the morning and GLISTIN-A instrument engineer Ron Muellerschoen and I were in northern Greenland at the Thule Air Base pier looking over the frozen Wolstenholme Bay. We’d been talking about the time Ron was wearing shorts here during the summer, but today it was the typical -22 Fahrenheit (-30 Celsius.) And even though over the past week we’d somehow gotten used to the cold and I was wearing a big parka, my legs were starting to get cold after walking for an hour. So we decided to head back.

As we turned around to go, I was struck in the face by the sun’s rays reflecting off the ice-covered ground. The brightness was astounding. And in that instant the meaning of “albedo” was seared into my brain in a way that went beyond reading about the science or looking at illustrations and animations.

There was something special about the experience of having the rays of the sun, which was sitting low in the high latitude sky, hit the ice surface at that extremely low angle and reflect off into my eyes.

Albedo is a measure of how reflective a surface is, how much light energy bounces off and reflects away and how much light energy gets absorbed. (Think hot asphalt on a sunny day. Black asphalt has a low albedo and absorbs light energy, while the brightest white has the highest albedo and reflects the light.)

Walking in Greenland
Team Oceans Melting Greenland (OMG) stands on the Greenland Ice Sheet. Notice the long shadows made by small rocks on the ground.
Albedo is part of what has stabilized Earth’s climate for millennia, because under normal conditions, the white of the polar ice reflects light energy back to space, keeping average global temperature stable. The more area covered by ice, the more heat reflected back to space. The more ice that melts, the more heat absorbed. Increasing temperatures are melting more ice, which exposes darker brown and green land and dark blue ocean. Those darker surfaces have a lower albedo, so they absorb more of the heat from the sun’s rays.

I stood for a moment, looking at the ground — a hard, dry, crusty mixture of ice and snow that made an exceptionally satisfying crunch crunch noise as our boots marched through it — and tried to figure out the color: 50 shades of white. I settled on white/light blue/silvery sparkle. Due to the low angle of the sun, the tiniest rough edge the size and shape of a pebble on the ground’s textured surface left a long, dark shadow.

No matter where we were or how we stood or what time of day, all day, every day, there were always long shadows — crazy long shadows. At 78 degrees north latitude, a full 12 degrees above the Arctic Circle, the sun will never be overhead. Never. I know that seems unbelievable, but even during the summer solstice, when Earth’s North Pole is tilted toward the sun, or during the four summer months of 24-hour daylight, the sun is always low, low, low at this latitude.

Low on the horizon

In that moment, I also understood another science question that had been bothering me. I’d been wondering why the meter-thick sea ice hadn’t yet begun to melt. Even though it was the end of March, even though the equinox had passed, the sun was out and the days were getting longer. In fact, up here the days were getting much longer, very quickly. On March 23, just three days after the equinox, we were already having 14-hour days with sunsets lasting past 9 p.m. That’s because in these high latitudes, the day length can increase by as much as 40 minutes per day. And by mid-April, just a few weeks after spring equinox, there will be 24 hours of daylight and the sun won’t set again until September. 

By mid-April the meter-thick layer of frozen seawater that covers the sea surface and fills the fjords will completely melt and expose the dark blue ocean underneath. But today, even in this brilliant sunshine, even on this day of 14-hour sunlight, the ocean was still completely frozen over. 

Greenland ice
The sun sits low in the sky even during midday. This iceberg calved off one of Greenland's coastal glaciers, floated into Wolstenholme Fjord and then became trapped in sea ice.
Just the other day in fact, a group of us walked about 3 miles (5 kilometers) across the frozen ocean into the middle of Wolstenholme Fjord to visit icebergs trapped in the frozen seawater. We hadn't worried at all about breaking through. 

But “Why?” I’d been wondering. Why, with all this extra sunshine, was the sea surface still so frozen? And why did that hard, dry, crusty mixture of ice and snow still remain on the ground?

In that instant, as the glint of the sunlight reflecting off the icy ground hit my face, I knew exactly why. It was the extraordinarily low angle of the sunlight that bounced right off the stunning bright whiteness of the ice. The sunlight was not absorbed by the ice and snow and instead was reflected away. It wouldn’t be until another month or so that the sun would get a little higher in the sky. And although the sun would never be directly overhead up here, it would be high enough to begin melting the ice.

No matter how much a person studies Greenland, or the northern latitudes, or albedo, or Earth in general, going into the field to experience those things can change your entire understanding of the world and how it works. I stood there for a moment, just allowing the high-latitude sun’s cold rays to glance off the snowy ice and shine straight into my face.

NASA’s Oceans Melting Greenland (OMG) team is here in Greenland; here to find out specifically how much ice the island is losing due to warmer ocean waters around the coastline. There is almost no ocean data in remote places like this, but OMG is busy working to change that, studying the complex ocean processes that affect Greenland's coastline because gathering data is critical to understanding Earth’s complex climate. This information will help us understand the amount of sea level rise we're going to have around the world.

Thank you for reading,

Laura

TAGS: EARTH, OCEANS, MELTING, GREENLAND

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NASA's modified G-III aircraft, with the GLISTIN-A radar instrument visible below, on the runway at Thule Air Base, Greenland.

Dive into a sea of Oceans Melting Greenland data

"Get to work." The phrase stuck in my head.

I had just walked out of a two-and-a-half-hour debriefing with NASA’s Oceans Melting Greenland (OMG) Principal Investigator Josh Willis, but the whole meeting could be summed up in those three little words of his: Get to work.

It was as though he’d been ringing one of those big ol’ dinner gongs. Data! Hot off the press! Come and get your data! Calling all oceanographers, geologists, paleo-climate scientists: come and get a big ol’ helping of free data.

He made me hungry for data, too.

OMG has just returned from its second spring season. Every April for five years, just before the ice starts to melt, OMG flies a radar instrument over almost every glacier in Greenland that reaches the ocean and collects elevation measurements within a 6.2-mile (10-kilometer)-wide swath for each glacier individually so we can measure how quickly each one is thinning. That’s literally hundreds of glaciers.

“We have more than 70 of these swaths that cover a couple hundred glaciers to create new elevation maps that are high accuracy, high resolution and high quality,” Willis said.

Greenland probe map
The blue squares on this Greenland map show 250 planned locations for probes dropped by plane into ocean waters near the coast. Called Aircraft Expendable Conductivity Temperature and Depth probes, they measure ocean temperature and salinity.

OMG also has bathymetry data from sonar and gravimetry. And we have a year’s worth of Airborne Expendable Conductivity Temperature Depth Probes AXCTD data collected last September plus hundreds of vertical profiles of temperature and salinity taken from ship surveys. “We have temperature measurements in many glacial fjords that have never had a historical temperature profile before. And none of that data is being used to its fullest extent yet.” OMG will set the baseline so we know what the water temperatures are today, and as we look to the future, we can watch them warm. That’s huge. 

I recounted all the times I’ve told someone that many parts of the ocean are still so unknown. I thought about all the times I’ve written about the OMG aircraft flying into remote, uncontrolled airspace, or researching the ocean water-ice interface around Greenland: So many of these places still nameless, still anonymous, still unidentified, still unknown. It’s mind blowing.

And somewhere in all this new data is information about the correlation between the ocean water and the ice as well as the answer to the question of how each glacier may or may not be affected by the waters offshore. “We know that warm water reaches a lot of glaciers. And there have been surveys in few places, but we’ve never had a comprehensive survey of the shelf water before,” Willis said.

OMG is mapping out the edges of glaciers and watching them change year on year on year. The mission measures glacial elevation in the last few kilometers before the glacier hits the water to see exactly how much the glacier shrank or retreated or both. In a few cases, the opposite might happen. Over a single year, a glacier might not have had as much calving or it might have slowed down, which would cause it to thicken and advance.

Aerial shot of a Greenland fjord
Aerial shot of a Greenland fjord shows, at the top, the glacier's origin in the ice sheet, and, at the bottom, its termination point, where it enters a frozen ocean.

There are literally hundreds of glaciers to research and dozens of papers buried in that data. And anybody who wants to can sift through it and publish. “You could get a Ph.D. done really fast,” Willis added enticingly. Here are some recommendations for interesting scientific research:

  • OMG’s temperature data could be used to write oceanography papers about where the warm water is on the shelf and to map out and catalogue which glaciers terminate in deep Atlantic water and which ones sit in shallow water. OMG has enough data to catalogue the depth of the faces of two-thirds of the glaciers around Greenland.
  • Paleo-climatologists and geologists can use new clearly mapped-out OMG bathymetry data to study how ancient glaciers carved troughs in the sea floor. Looking at maps of the seafloor will help us understand the implications for Greenland’s ancient ice sheet. Some flat-bottomed troughs, for example, show evidence of where little ancient rivers must have carved their way through to erode the paleo-glaciers. And sea floor sediments could be analyzed to find out how far the ancient glaciers advanced.
  • Overview papers that compare and contrast the east, west, north and south coasts of Greenland would be incredibly useful to have.
  • Some elevation maps made from historical datasets as well as a few decades’ worth of temperature measurements already exist for some isolated regions across Greenland. Using these historical maps, it’s now possible to compare them with current measurements of temperature and elevation in these locations to observe the changes.
  • OMG is also gathering oceanography data around Greenland. Since the Atlantic Ocean water is very warm and salty and the Arctic Ocean water is cold and fresh, the ratio of those two could be analyzed. Warm Atlantic Ocean water has been in the coastal area around Greenland forever, but how much Atlantic water makes it onto the shelf and reaches the glaciers? This is affected by the bathymetry and the winds, which affect the local currents. And according to Willis, “There’s really still a lot to learn.”

Already there are four downloadable datasets right here! So, come and get it, all you hungry Ph.D. oceanographers.

Get to work.

I can't wait to read your papers,

Laura

TAGS: EARTH, OCEANS, MELTING, GREENLAND

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Scientists strike out for a wall of ice in the far north, where rapidly changing glaciers are being tracked by a project called "Oceans Melting Greenland."

NASA flies northward to monitor Greenland’s glaciers

I looked out the window of NASA’s modified G-III aircraft across the expanse. I knew what I would see. I knew it would look like white pillow-y ripples going on and on and on, way farther than anyone could see, like a vast field of white sand dunes stretching away into the distance.

The Oceans Melting Greenland (OMG) aircraft was flying across the entire top half of Greenland from the northwest coast to the northeast coast to make the day’s first science measurements. And the first science flight line was all the way across the Greenland Ice Sheet, across 620 miles (1,000 kilometers) of ice that’s up to 2 miles thick and hundreds of thousands of years old. And although I’d flown in Greenland a bunch of times before, I’d only ever flown over the coastal areas, where glaciers around the ice sheet’s edges carve their way through the Greenland terrain, to cut out deep, narrow fjords over centuries’ time.

Everything here is vast and expansive: the size, the views, the enormous quantity of ice.

Two days before, I’d trekked up to the ice sheet with a few members of the OMG team. We stood in the insanely cold, dry, biting air (Greenland is one of the least humid areas on planet Earth, with the cleanest, clearest air) and gazed into the incomprehensible distance. It was easy to use a snow boot to scrape the 2 inches or so of fine, dry, powdery snow away from the ice sheet to uncover the hard, greenish blue ice.

On the edge of the ice sheet, a slice of ancient ice layers was exposed like a glistening wall, and we’d walked past it on the way up to the top of the sheet. The ice wall was so vertical and so sheer, the snow that hid the other parts of the edge had fallen away, and we could see its smooth surface shining like a gem: striped blue and green. That ice is hundreds of thousands of years old, made from snow that fell year after year after year, eventually becoming compressed and preserved in this cold, dry desert environment. 

Standing on top of the ice sheet, I imagined it under my feet, going down and down and down for a mile or more. 

A mile—or more—of ice.

An exposed wall reveals ice that is hundreds of thousands of years old on the edge of the Greenland ice cap. Credit: NASA/JPL.
An exposed wall reveals ice that is hundreds of thousands of years old on the edge of the Greenland ice cap. Credit: NASA/JPL.

Everything here is vast and expansive: the size, the views, the enormous quantity of ice. Flying over them, the glaciers look like hundreds of broad frozen rivers, each one up to a few miles across, each one channeling its way from the interior of the landmass toward the sea over thousands of years. Each glacier carved out a fjord through the rock and out to sea in the same way a river erodes its channel, except it’s so much bigger, so much slower and the erosional power of the ice is so much more intense. From up here, the glacier’s impossibly slow creep seems frozen in both space and time. But the glaciers are moving. Stress fractures or crevasses, which are easy-to-observe evidence of glacier movement, form as the glaciers slope downhill toward the sea. And of course, we also have scientific measurements. Detailed satellite images show that the terminal edges of many glaciers such as Jakobshavn have receded by as much as 0.4 miles (600 meters) per year in recent times. Scientists also have time-lapse footage of seaward glacier flow.

But having evidence of glacier flow, and even glacier recession, is only part of the story. As a warmer atmosphere and a warmer ocean around the coastline continue to melt the massive amount of ice that covers Greenland, the ice ends up flowing into the ocean, which causes sea level rise worldwide.

A glacier flows toward a frozen fjord on the Greenland coast, as seen from NASA's modified G-III aircraft. Credit: NASA/JPL
A glacier flows toward a frozen fjord on the Greenland coast, as seen from NASA's modified G-III aircraft. Credit: NASA/JPL.
OMG is hoping to gather enough information about the melting glaciers to better predict sea level rise. And that explains why we were here in our NASA G-III on a March morning, flying lines over Greenland’s receding glaciers with our GLISTIN-A Ka-band interferometer radar instrument. “We want the big picture,” said Josh Willis, OMG principal investigator, “and these lines give us data for almost every glacier that reaches the water.  If the ocean is eating away at the edges of the ice sheet, we’ll see it. Bigtime.”

As we flew over, the GLISTIN-A instrument received data from a 12-kilometer swath of whatever is below and off to the sides of it, in this case glaciers. Using these data, we can measure, with great precision, the height of each glacier we fly over. See, when the end of an individual glacier melts and calves into the ocean, the whole glacier speeds up and flows even faster downhill toward the ocean because there’s less friction against the sides and bottom to slow it down. The faster it moves, the more it stretches — like pulled taffy — and when a glacier is all stretched out, its elevation is lower. And because OMG will fly the same science lines along the same coastal glaciers every year for five years in a row, we’ll be able to find out how much elevation each glacier has lost, how fast it’s flowing into the ocean and how much ice has been lost.

NASA's OMG is monitoring the speed of glaciers around Greenland's coastline. Credit: NASA/JPL
NASA's OMG is monitoring the speed of glaciers around Greenland's coastline. Credit: NASA/JPL.
Over my headset, I can hear the pilots discussing the flight path with the instrument engineers. Out the window, I can see Greenland’s northernmost glaciers below us; white upon white upon white.

They sure appear stable, still, enduring. But they’re not. They’re melting.

They sure appear stable, still, enduring. But they’re not. They’re melting.

And northern Greenland, along with the rest of the higher latitudes in the Northern Hemisphere, is experiencing some of the most intense impacts of global climate change right now, today.

OMG.

Thank you for reading.

Laura

TAGS: EARTH, GREENLAND, GLACIERS

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Earth with directions

Greenland is one of the few places that’s harder to get to than outer space

I’m going to Greenland. I told my brother, and he replied, “Oh cool, I’m headed to Ireland.” That’s the typical response, as if Greenland were just some place one could book a ticket to, with commercial airports, and hotels, and restaurants and stuff. But … no, Greenland is different. It’s actually not an independent country, for example. (It’s a territory of Denmark.)

The other response I keep getting is that dumb, corny comment about it not being green. So it seems like the only thing we collectively understand about Greenland is that it’s a place to go and it has a hypocritical name.

But that is just so wrong. My husband and I finally got on the same page this morning when he opened the Google Maps satellite view of Kangerlussauq Airport, where I’m scheduled to land. “Oh,” he said. “It’s a barren dirt strip in the middle of nowhere and nothing.”

At last, an acknowledgement of the truth. The only place that’s harder to get to than Greenland is outer space. I know that sounds funny, but I’m not even kidding. (Okay, okay, Antarctica is also hard to get to, along with the Marianas Trench. Ugh.)

I first became aware of how little we know about Greenland when I was creating NASA’s Global Ice Viewer for our climate website. I found shots from Alaskan glaciers that dated all the way back to the late 1800s for the gallery. Gents with top hats and ladies in bustles with Victorian cameras stood on the ice. But Greenland? Photos taken before the 1980s are extremely rare.

Muir Glacier, Alaska, disappears.
Muir Glacier, Alaska, disappears. Left image: 1891. Right image: 2005. Photographed by G.D. Hazard in 1891 and by Bruce F. Molnia in 2005. Courtesy of the Glacier Photograph Collection. Boulder, Colorado, US and the National Snow and Ice Data Center/World Data Center for Glaciology.

And while most people understand that increased atmospheric temperatures have been melting the ice sheet from above, global warming has also been increasing ocean temperatures. And this means the ocean waters surrounding Greenland are also melting the ice sheet from around its edges.

Which is the reason I’m headed up there with NASA’s Oceans Melting Greenland (OMG) campaign in the first place: to measure the temperature and salinity of those unknown waters. See, the fresh water that flows into the ocean from ice melt is about 0 degrees and less dense, so it floats right at the sea surface. The North Atlantic Ocean Water is about 3 or 4 degrees, salty and denser, so it sits right below the fresh melt water. And these two waters don’t really mix much. When the 3- or 4-degree North Atlantic Ocean Water gets in contact with Greenland’s ice sheet, it’s warm enough to melt it.

But no one knows the melt rate yet. No one.

Even though Greenland’s melting ice sheet impacts each and every one of us right now. The rate of ice melt will determine how much sea level rise we’re going to get, 5 feet or 10 feet or 20, everywhere, all over planet Earth, not just in Greenland, but at coastlines near you and me.

This is where that whole NASA “exploring the unknown” theme comes in. Next week, the OMG team (including yours truly) will be in Greenland on NASA’s G-III aircraft. We’ll spend five weeks flying around the entire coastline, measuring the salinity and temperature of the coastal waters by dropping 250 Aircraft eXpendable Conductivity Temperature Depth (AXCTD) science probes through a hole in the bottom of the plane. The reason we’re going in September is that’s the warmest time of the year in the ocean, the ice will reach its lowest extent and we’ll be able to measure as much of the coast as possible. The plan is to repeat the same mission for five years to find out what the melt rate is and how much that rate is increasing.

Am I excited? Yes, beyond. Aside from the science preparation, it took months and months of personal prep. I passed a Federal Aviation Administration medical exam, then got trained in First Aid, CPR, AED, hypoxia, disorientation, survival, and hearing conservation, and then had to buy steel-toed shoes, which are required to fly on that NASA plane. Today, I am psyched beyond belief.

Underwater disorientation training in action.

Why else would anyone work so hard to do something? Just like the rest of the team, I hope our work really makes a difference.

TAGS: GREENLAND, EARTH, NASA, JPL, JET PROPULSION LABORATORY, GLOBAL WARMING, OCEANS

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Greenland's southwestern coastline

Where ice meets water at the bottom of the sea.

A person can look at a thing over and over again before finally seeing it for the first time. That’s how I felt standing in front of an Arctic map at the University of Washington in Seattle. I gazed at the northwest coastline of Greenland, north of Baffin Bay, up where the Canadian Queen Elizabeth Islands come close to Greenland.

Of course I’ve looked at Arctic maps before, from a zillion different angles. Normally I’m the one pointing and explaining. “Look at how small the Arctic area is. It’s a shallow sea, mostly surrounded by continents and islands where sea ice forms and gets trapped,” I say, encouraging folks to get as excited as I am about this remote part of the planet that’s chopped up, spread out and distorted by most maps. But this time, standing next to James Morison, senior principal oceanographer from the University of Washington, I was the one listening, looking closely and being amazed.

We were in the hallway of the Applied Physics Laboratory’s polar science wing, taking a break between Oceans Melting Greenland (OMG) science team presentations. The walls were lined with photos of teams out on glaciers, ice drilling equipment, ice sheets of the world and grand ice-covered landscapes. Ice, ice and more ice, and penguins. There were pictures of polar bears and narwhals, too. But Greenland’s jagged coastline had me captivated. The islands, the convolutions, the fjords: phenomenal, mindboggling. I couldn’t take my mind off it.

Greenland's northwestern coastline in September 2015 during Phase 2 of the TerraSond / Cape Race Bathymetry survey. Credit: NASA/JPL.
Greenland's northwestern coastline in September 2015 during Phase 2 of the TerraSond / Cape Race Bathymetry survey. Credit: NASA/JPL.
Are you desperate to grab a map right this second to have a look? Do it.

But the Oceans Melting Greenland team is doing more than looking at maps of Greenland. Way more. “We’re trying to look under the ice,” Principal Investigator Josh Willis told me. “What is the sea floor like under there? What is the interface between where the bottom of the ice sheet reaches out over the seawater and down into the ocean?”

The seawater around 400 meters (1,312 feet) deep is 3 to 4 degrees Celsius (5 to 8 degrees Fahrenheit) warmer than the water floating near the sea surface. And the shape of the sea floor (bathymetry) influences how much of that warm, subsurface layer can reach far up into the fjords and melt the glaciers. The OMG team wants to measure how much of that warm water could be increasing due to climate change.

What will the future hold? Will we see 5 feet of sea level rise … or 10 or 20?

And even though Greenland feels untouched and remote, feels so “Who cares?” we all need to be concerned about its complex coastline and the rapid pace of its melting ice sheet. NASA’s GRACE satellites observed Greenland shedding a couple trillion—with a “t”—tons of ice over the last decade, and the rate of melt is increasing. So that winding coastline and those unfamiliar fjords have already impacted all of us—yes, that means you—undoubtedly, no matter how far away or how far inland you reside.

As each of the dozen or so OMG members took his or her turn updating the team on their most recent topography, temperature and salinity measurements, I noticed a trend. Everyone kept repeating the phrases “never been surveyed before,” “it’s a very tough area,” and “these fjords are so very small, they have no names and have never been visited before.” They are literally exploring these unknown areas in detail for the first time.

My mind drifted off to the edge of that unimaginably complicated winding coastline, that unknown place where ice meets water meets seafloor, where the ice is melting as fast as we can measure. And I had to stop the group to ask why. Specifically, why is it so tough? Why has no one been there before? It turns out this area is difficult to navigate because big chunks of remnant sea ice clog up the water. The crew has to snake in between floating icebergs and weave in and out of the narrow fjords. It’s rather treacherous. And weather conditions can be challenging up there. The other reason this area is so unknown is that the glacier has retreated so recently that the coastline is changing as fast or even faster than we can study it.

Last summer, a small group that included UC Irvine graduate student Michael Wood sailed on the M/V Cape Race deep into some of the most jagged areas around southeastern Greenland, which, according to Co-Investigator Eric Rignot, is the “most complex glacier setting in Greenland.” After more than 7,871 kilometers (4,250 nautical miles) and more than 300 Conductivity, Temperature Depth (CTD) casts, the first bathymetric survey was completed.

Over the next five years, OMG will measure the volume of warmer water on the continental shelf around Greenland to figure out whether there is more warm water entering the fjords and increasing ice loss at the glacier terminus.

Greenland's northwestern coastline in September 2015 during Phase 2 of the TerraSond / Cape Race Bathymetry survey. Credit: NASA/JPL.
Greenland's northwestern coastline in September 2015 during Phase 2 of the TerraSond / Cape Race Bathymetry survey. Credit: NASA/JPL.

Here are some details about the OMG plan:

  • Every year for four years, survey glacier elevation near the end of marine-terminating glaciers around Greenland’s coastline using NASA’s airborne synthetic aperture radar altimeter GLacier and Ice Surface Topography INterferometer (GLISTIN-A).
  • Every year for five years, deploy 250 Aircraft eXpendable Conductivity Temperature Depth (AXCTD) probes to measure temperature and salinity of the waters around Greenland from one of NASA’s G-III aircraft.
  • Use a ship with multi-beam sonar to measure bathymetry of the seafloor up very close to the extremely jagged coastline of Greenland, as well as a small vessel with a single beam going up into small places, driving up fjords and getting as close to glaciers as is safe.
  • Collect gravity measurements from small planes in Northwest, Southeast and Northeast Greenland to help map the sea floor in places the ships cannot go.

Find out more about Oceans Melting Greenland.

View and download OMG animations and graphics.

Thank you for your comments.

Laura

Oceans Melting Greenland is part of NASA Earth Expeditions, a six-month field research campaign to study regions of critical change around the world.?

TAGS: ICE, SEA, GREENLAND, SOUTHWESTERN COASTLINE

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NASA’s modified Gulfstream-III on the runway at Ellington Field Airport in Houston, Texas, with OMG scientists and engineers aboard.

We know more about the moon and other planets than we do some places on our home planet. Remote parts of the world ocean remain uncharted, especially in the polar regions, especially under areas that are seasonally covered with ice and especially near jagged coastlines that are difficult to access by boat. Yet, as global warming forces glaciers in places like Greenland to melt into the ocean, causing increased sea level rise, understanding these remote places has become more and more important.

This past spring, Oceans Melting Greenland (OMG) Principal Investigator Josh Willis led a team of NASA scientists to begin gathering detailed information about the interface between Greenland’s glaciers and the warming ocean waters that surround them. The next step in accessing this extremely remote region involves dropping a series of Airborne Expendable Conductivity Temperature Depth, or AXCTD, probes that will measure ocean temperature and salinity around Greenland, from the sea surface to the sea floor. With this information, they hope to find out how quickly this warmer ocean water is eating away at the ice.

Since no one has ever dropped AXCTDs through a tube at the bottom of a modified Gulfstream-III, the OMG team headed to Ellington Field Airport near NASA’s Johnson Space Center in Houston, Texas, for a test drop into the Gulf of Mexico. I went along for the ride.

"In position!"

Expert NASA T-38 pilot Bill Rieke executes his flight plan to rendezvous with the Oceans Melting Greenland (OMG) scientists and engineers aboard NASA’s modified Gulfstream-III at “drop one.” As soon as photographer James Blair is ready with his high speed and high definition cameras, he calls out “In position!” from the supersonic jet to the team in the G-III over Very High Frequency (VHF) radio. 

The money shot

It’s up to Derek Rutovic, G-III program manager at NASA’s Johnson Space Center, to visually inspect the release of the AXCTD to make sure it does not impact the plane and then to see that the parachute opens. The first test drop was released while the plane was flying at a height of 5,000 feet and a speed of 180-200 knots. 

Temperature and salinity

Alyson Hickey and Derek Rutovic prepare the AXCTD tubes for deployment. After these test flights are complete, the mission heads up to Greenland this fall, where the AXCTDs will measure temperature and salinity around Greenland to make a detailed analysis of how quickly the warmer waters around Greenland are eating away at the ice sheet.

3, 2, 1 ... drop!

G-II pilot Bill Ehrenstrom calls out “Three, two, one, drop!” over the Very High Frequency (VHF) radio channel to signal Rocky Smith, who then pushes the AXCTD tube through a hole in NASA’s modified Gulfstream-III. Rocky then announces, “AXCTD is clear.” 

AXCTD sails down

Oceans Melting Greenland (OMG) Project Manager Steve Dinardo and OMG Principal Investigator Josh Willis wait for a radio signal as the AXCTD sails down through the air to indicate it’s arrived at the sea surface. Once it hits the sea surface, it releases its probe, which travels through the ocean to the sea floor and sends ocean temperature and salinity data up to the team in the aircraft above, who monitor the data in real time. 

The flight path

Both aircraft must execute a complex flight path, which involves filming two precision AXCTD test drops minutes apart.

Details, details, details

debrief
To execute the precision flying required to photograph the test drop of a series of AXCTDs, the team is briefed before and after all flights, where every detail is explicitly coordinated. From left: Flight Engineer Alyson Hickey, Oceans Melting Greenland Principal Investigator Josh Willis, photographer James Blair, Oceans Melting Greenland (OMG) Project Manager Steve Dinardo and NASA Gulfstream-III Program Manager Derek Rutovic.

Find out more about Oceans Melting Greenland.

View and download OMG animations and graphics.

Thank you for your comments.

Laura

Oceans Melting Greenland is part of NASA Earth Expeditions, a six-month field research campaign to study regions of critical change around the world.

TAGS: OMG, TESTING, WATERS, OCEANS, MELTING, GREENLAND

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This shot of Greenland was captured from the window of NASA's modified G-III airplane for the Oceans Melting Greenland (OMG) campaign.

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And this is how I know you’ve noticed NASA’s latest airborne campaign, where NASA scientists fly a bunch of NASA instruments on a NASA airplane to study more details about Earth. Cool, right?

Lately, we’ve been flying around the edge of Greenland collecting radar data about how much its glaciers are melting into the sea. And the most common comment we get goes something like “Wheee! Let’s go. Take me with you.” When I told a friend about the possibility of joining the team in the field, she exclaimed, “All expenses paid?”

HAHAHA … no. As if a NASA expedition to Greenland is like a resort vacation instead of a giant heaping pile of hard work.

“When I looked down at the rivers of ice running into the ocean, it was shocking to think about the effects of rising sea levels as far away as California or Antarctica,” said Principle Investigator Josh Willis, two days after returning from his first trip to observe this pristine part of our planet as it melts into the sea and goes bye-bye. “Yet, I had a blast.” Because even though we all probably have many complex emotions about climate change, ice mass loss and sea level rise, we can still simultaneously feel super duper stoked about the chance to fly over the glaciers of Greenland in a freaking NASA plane. “The mountains, the ice, the water and the ice in the water are incredibly striking even though it’s lonely to see it disappearing at the hands of human activity,” he told me.

Yes, emotions are weird, and yes, there’s an awkward contrast or odd juxtaposition between feeling both thrill and grief at the same time.

But that’s life, I guess.

So just in case you’re still envisioning a champagne-swilling, caviar-scoffing, gangsta, hip-hop music video scene, here are a few things that might surprise you about the kind of major effort it takes to get on board NASA’s G-III plane and join the Oceans Melting Greenland field campaign:

Kick booty in a fire-resistant flight suit

OMG Principal Investigator Josh Willis (far left and far right) "joshing around" with videographer Rob Andreoli, technician Robert "Rocky" Smith, pilot Thomas Parent and radar operators Tim Miller and Ron Muellerschoen.

OMG Principal Investigator Josh Willis (far left and far right) "joshing around" with videographer Rob Andreoli, technician Robert "Rocky" Smith, pilot Thomas Parent and radar operators Tim Miller and Ron Muellerschoen.

So, you think you’d kick some booty in one of these flight suits? Oh, yeah. Totally. Well, so do we. Would you kill to have one? But the real reason the pilots think they’re so fab is because they’re fire-resistant. They. Resist. Fire! With racks and racks of science equipment wired with electrical cables, the crew has to be extra careful about fire on the plane. So wearing one of these flight suits is required.

A load of gas and no mistakes

A day's flight plan is often complex due to Greenland’s jagged coastline, which is more than 27,000 miles long, longer than the distance around Earth at the equator. The blue lines indicate the plane’s potential flight path.

A day's flight plan is often complex due to Greenland’s jagged coastline, which is more than 27,000 miles long, longer than the distance around Earth at the equator. The blue lines indicate the plane’s potential flight path.

A trip to Greenland sounds all romantic ‘n’ stuff, but operating a science instrument aboard a flying science lab on a six-hour flight every day is hard work. Just check out these flight paths. According to Project Manager Steve Dinardo, “You get a full load of gas and no mistakes.” Notice the flight path zigzags across the complicated coastline of the entire island. That’s because global warming of Earth’s atmosphere is melting the top of the ice sheet. But, aha! The ocean water around Greenland is even warmer than the air. That warm water is busy melting the glaciers from around their edges, hence the name, Oceans Melting Greenland, which will find out exactly how much of this melting is going on.

Instruments, instruments and more instruments. And did I mention some serious training?

Project Manager Steve Dinardo and me aboard NASA’s modified G-III. A serious lack of champagne and caviar, but check out all that science equipment.

Project Manager Steve Dinardo and me aboard NASA’s modified G-III. A serious lack of champagne and caviar, but check out all that science equipment.

The NASA modified G-III aircraft is … modified. (Did you notice the word “modified”?) What modified means is the plane has holes in it so experimental science instruments can stick out. And more scientific instruments are attached in, under and onto the plane in all sorts of configurations. To get to fly on this baby, you’d better have some training. Yep, some serious training: Safety training, first aid training, survival training. You get the idea.

Keep warm, in style

If you’re planning to be cold, it’s best to do it in style.

If you’re planning to be cold, it’s best to do it in style.

I can work the runway like a glamazon in this red coat, but it’s rated for survival in 50 degrees below zero. I said survival. In case of emergency. Does this sound like your all-inclusive vacation package now? With a survival coat? And there’s a survival vest too, with a beacon attached, and food rations, a pocketknife tool set, fishing gear, first aid supplies, a radio and a laser pointer for playing with cats—oops, I mean for signaling emergency and attracting rescue. The thing weighs about 20 pounds. Everyone on the plane has one of these puppies, and you’d better believe they know how to use it. If there’s a problem, the team would have to survive three to five days out in the wilderness until they're rescued. I don’t mean to scare you, but at NASA, when we say we care about safety, we’re not messing around.

“It’s not a triumph of human achievement that we’re melting the ice sheet,” said Willis. “When you see how huge these glaciers are and this huge chunk of this ice sheet disappearing into the ocean, it’s almost incomprehensible even when you see it from 40,000 feet.”

Wheee.

Find out more about Oceans Melting Greenland here.

View and download an OMG poster/infographic here.

Thank you for your comments.

Laura

Oceans Melting Greenland is part of NASA Earth Expeditions, a six-month field research campaign to study regions of critical change around the world.

TAGS: GREENLAND, OCEANS, MELTING, GREENLAND, OMG

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One of NASA's modified G-III aircraft in the hangar at Armstrong Flight Research Center being prepped for a mission to study glaciers around Greenland.

Dr. Josh Willis oversees integration of the GLISTIN-A radar instrument to the belly of the aircraft.

We overlook Greenland ice loss at our own peril. It’s one of the largest contributors to accelerating sea level rise, and in the U.S. alone, nearly 5 million people live in 2.6 million homes at less than 4 feet above high tide. If you happen to be one of them, you should definitely pay attention to Greenland.   

Yes, yes, Greenland is melting. You already knew that…probably. And the giant flux of fresh water pouring out of the second largest ice sheet on the planet isn’t slowing down anytime soon. Greenland’s ice melt is actually accelerating. In the last decade alone, NASA’s twin GRACE satellites measured it gushing 2 trillion tons of ice like a fire hose pouring fresh water into the North Atlantic.

But it’s easier to focus on politics, celebrity gossip, reality TV and cat videos than on Earth’s climate. It seems like everyone’s all “Greenland? Who cares. Whatever. Next.” And that upsets me.

Is it really that easy to pretend the effects of global warming don’t exist?

We overlook Greenland ice loss at our own peril. It’s one of the largest contributors to accelerating sea level rise, and in the U.S. alone, nearly 5 million people live in 2.6 million homes at less than 4 feet above high tide. If you happen to be one of them, you should definitely pay attention to Greenland.   

Fortunately for all of us, NASA is paying attention to Greenland in a big way. We’re so concerned about the amount of ice loss that we’ve named a Greenland observing expedition Oceans Melting Greenland, or OMG for short, because that's the most appropriate response to the phenomenon.

This week, OMG heads up north on one of NASA’s G-III modified airplanes to continue a five-year mission that will look closely at how warming ocean water interacts with glaciers surrounding Greenland and melts them. The project began this past year by mapping undersea canyons via a ship equipped with an echo sounder. For this next part of the investigation, a radar instrument attached to the bottom of the G-III, called the Airborne Glacier and Land Ice Surface Topography Interferometer (GLISTIN-A), will be able to measure precisely how much the oceans are eating away at the edges of the ice on a glacier-by-glacier basis.

Instrument integration (a fancy word for attaching instruments to planes and making sure they work and don’t come loose) went down at NASA’s Armstrong Flight Research Center, and Principal Invesigator Dr. Josh Willis, Project Manager Steve Dinardo, Co-Investigator Dr. Ian Fenty and I headed there to check it out.

Glaciers on the edge 

As the technicians and engineers tweaked fistfuls of wires, we crawled in, under, through and around the aircraft. Then Dr. Ian Fenty (who helped design the flight plan) and I sat aboard our flying science lab and talked ice loss for a while. “We often find that a glacier that’s been retreating a lot might be in 1,000 feet of water,” he explained. “Whereas the glacier that’s not thinning very much is in water that’s only 100 or 200 feet deep.” That’s because the layers of ocean water around Greenland are in a very unique situation, where you have colder fresh glacier meltwater near the surface over salty ocean water that, due to climate change, has been warming. The water found at 600 feet and below is a relatively warm 4 degrees Celsius compared with the surface water, which is just near freezing at 0 degrees. This means that the “primary suspect” behind the acceleration of Greenland’s melting glaciers is the warming ocean waters that can get right up against the edge and interact with the glacier itself.

As the surface of lower elevation glaciers melts, the water percolates through the ice and forms giant subglacial channels, like a river system under the ice. If the ice running through these narrow rivers breaks off, the friction between the glacier and the substrate gets reduced a bit and literally stretches the ice so the glacier thins out. OMG’s GLISTIN-A radar is going to measure the height of the ice. “If we see a change in elevation from one year to the next, we can know how much ice is being lost and how much the movement of the glacier is speeding up.” Over the next five years OMG plans to go back to Greenland to look for more changes.

As I left the hangar and headed home, I thought about how Greenland is such a weird part of the world and how much I hope our society can put aside its troubles so we can work together to preserve it.

Find out more about Oceans Melting Greenland here.

Thank you for your comments.

Laura

TAGS: GREENLAND, EARTH, MELTING, GRACE, ICE, CLIMATE CHANGE, GLOBAL WARMING

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M/V Cape Race at Kullorsuaq, Greenland

This morning when I told someone I’d interviewed NASA oceanographer Josh Willis for this blog, they replied, “Isn’t Josh Willis a climatologist?”

“Aha!” I said. “That’s a problem. Not knowing that Earth’s ocean is responsible for controlling the climate is major. Oceanographers are climatologists.”

I mean, look, the ocean covers 71 percent of the planet’s surface, and 71 percent is like, duh, a lot. The ocean, in fact, is so important that a better name for our planet would have been “Ocean” rather than “Earth” — even though our species spends most of its time on boring old land. #sorrynotsorry, geologists.

And you might not realize this because it’s so familiar, but water is crazy. It has this unusual property, called “high heat capacity,” that gives it the ability to hold a stable temperature. It resists heating and cooling. Water will absorb a lot of energy before it changes temperature even a little bit.

And this property of water, this high heat capacity, is what makes life on our planet possible. It’s also what controls and moderates our climate, which is why our ocean, more than our atmosphere, is responsible for creating a stable climate on Earth.

So this is the reason oceanographers are climatologists. It’s also part of the reason Willis chose to name his new science project Oceans Melting Greenland (OMG). He hopes that people everywhere will recognize the role Earth’s ocean plays in controlling the climate and to say to the world, “Hey! The ocean is eating away at the ice sheet! The ocean is playing a huge role in melting the glaciers; it's melting Greenland!”

Remember I just told you water absorbs a lot of energy before it heats up? Well, humans have added so much energy to the Earth system by burning fossil fuels that we have heated the ocean. And now that we’ve warmed it up, you guessed it: The water is in no hurry to change back, so we’re going to be stuck with this warmer water for a very long time. And, says Willis, “Since Greenland is one of the last two remaining ice sheets on the planet, its fate is intertwined with how much destruction we’re going to have with climate change.” If you just said “OMG,” you would be right.

But if you think scientists know everything there is to know about the ocean, you would be very wrong. Willis and his team want to find out more about the complicated geometry (the shape and depth of the seafloor) around Greenland to understand the interaction between the water and ice so that we can find out how fast the glaciers are melting.

graphic showing M/V Cape Race route

M/V Cape Race ship track for phase 1 of 2015 OMG survey. Credit: Ian Fenty

This summer OMG used a ship, M/V Cape Race, to sail right up the narrow fjords on the continental shelf surrounding Greenland to the places where the 4- to 5-degree Atlantic Ocean water meets the bottoms of the frozen zero degree glaciers. The Cape Race used a multibeam echo sounder to map undersea canyons where the warm seawater comes in contact with and melts the glaciers. Willis followed the ship’s path via smartphone, sitting up in his PJs at two o’clock in the morning and uttering a variety of exclamations, including “OMG, turn left, left!”

Next year, the Cape Race will continue to make its way around Greenland, mapping the depth of the seafloor near the fjords, while Willis joins his team in the field flying on NASA’s G-III plane.

“OMG is a big picture project,” he told me. ”We want to see what’s happening in the ocean on the large scale and what’s happening to the ice sheet on the largest scales.”

In the spring, the NASA aircraft, with Willis aboard, will measure how much Greenland glaciers are thinning using the Glacier and Ice Surface Topography Interferometer (GLISTIN-A) instrument. They plan to deploy temperature and salinity probes in the summer. “In most of these places, there’s been no temperature and salinity data collected,” Willis said pausing, “ever.” Over the next five years, they will continue to monitor the ice sheet, asking, “When the water is this warm, how much ice melts?”

Willis knows “OMG” is a campy name for a NASA mission that makes light of a serious subject. “It’s easier to accept something as a reality when you can laugh at it, and accepting reality is a step towards making a change,” he said, explaining that if he was bummed out about climate change all the time, he would be stuck. “Humor makes it tolerable.”

Hopefully, when you find out about Oceans Melting Greenland, you’ll respond in the only way that’s appropriate: “OMG!”

Find out more about Oceans Melting Greenland here, here and here.

View an infographic about the mission.

Thank you for reading, sharing and commenting.

Laura

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TAGS: EARTH, ICE, GREENLAND, OCEAN, CLIMATE CHANGE

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