Tag Archives: polar

Pine Island Glacier: A Quest to Understand Antarctic Ice Loss

Posted on by .

NASA recently posted a press release about an upcoming expedition to Pine Island Glacier Ice Shelf, a key piece of real estate in Antarctica that’s slipping into the ocean at an increasingly worrisome pace. This month, in fact, an aircraft participating in Operation IceBridge spotted a lengthy crack cutting across the massive sheet of floating ice. There wasn’t much room for many details in the release, so here’s a longer description of the upcoming expedition from Goddard’s cryosphere writer, María José Viñas, for polar science aficionados.


An international team of researchers will helicopter onto thePine Island Glacier ice shelf, one of Antarctica’s most active, remote andharsh spots, in mid-December — weather permitting. Their objective: to determinehow changes in the waters circulating under the fast-melting ice sheet arecausing the glacier to accelerate and drain into the sea.

If all goes to plan,the multidisciplinary group of 13 scientists, led by NASA’s emeritusglaciologist Robert Bindschadler and funded by the National Science Foundation(NSF) and NASA, will depart from McMurdo stationin mid-December and spend six weeks on the ice shelf. The team will use acombination of traditional tools and sophisticated new oceanographicinstruments to measure the ocean cavity shape underneath the ice shelf. Theyaim to determine how streams of warm water enter this cavity, move toward thevery bottom of the glacier and melt its underbelly, making it dump more than 19cubic miles of ice into the ocean each year.

“The project aims to determine the underlying causesbehind why Pine Island Glacier has begun to flow more rapidly and dischargemore ice into the ocean,” saidScott Borg, director of NSF’s Division of Antarctic Sciences, the group thatcoordinates all U.S. research in Antarctica on the southernmost continent and surrounding oceans.”This could have a significant impact on global sea-level rise over thecoming century.”


“Darn hard to get to”

Pine Island Glacier has long been on the radar screen of Antarcticresearchers.

“Once satellite measurementsof Antarctica started to accumulate and we began to see which places werechanging, this area lit up as a spot where there was a large change going on,”Bindschadler said.

Bindschadler was the first person to ever set foot on thisisolated, wind-stricken corner of the world in January 2008. Previously,scientists doubted it was even possible to reach the crevasse-ridden ice shelf.But Bindschadler used satellite imagery to identify an area where planes couldland safely.

“The reason we haven’t gone therebefore is that it’s so darn hard to get to,” Bindschadler said. “So provingthat landing was doable was a relief.”

The glaciologist’s joydidn’t last: the ground proved to be too hard for the planes transporting theinstruments to land repeatedly. Logistics experts determined they would have touse helicopters to transport scientists and instrumentation in and out the iceshelf, and the whole plan for field campaigns had to be redesigned around thehelicopters’ availability.

Almost four years after thisfirst landing, Bindschadler and his team will be returning to the ice shelf tostudy its innards.

Scientists have determined that it’s the interaction ofwinds, water and ice that’s driving ice loss. Gusts of increasingly stronger westerlywinds push the Antarctic Circumpolar Current’s cold surface waters away fromthe continent: then, warmer waters that normally hover at depths below thecontinental shelf rise. The lifting warm waters spill over the border of thecontinental shelf and move along the floor, all the way back to the groundingline—the spot where the glacier comes afloat— causing it to melt. The warmsalty waters and fresh glacier meltwater combine to make a lighter mixture thatrises along the underside of the ice shelf and moves back to the open ocean, meltingmore ice on its way out. But, how much more ice melts?  Bindschadler and his team need to findout to improve projections of how the glacier will melt and contribute to sealevel rise.

“All existing data (satellite images, variability of winds,submarine measurements) say this a highly variable system”, said Bindschadler.“But they’re all snapshots in time. Our team will be deploying instrumentationthat will get a longer record of the variability.”

Profiling oceanwaters
One of the first tasks for the teamwill be using a hot water drill to make a 500-meter deep hole through the iceshelf. Once the drill hits the ocean, the scientists will send a camera to peerinto the ocean cavity, observe the underbelly of the ice shelf and analyze theseabed lying 500 meters below the ice.

Then, they will lower a setof instruments that Tim Stanton, an oceanographer with the Naval PostgraduateSchool, has built. The primary instrument in the package is
an ocean profiler, which will move up and down avertical cable that connects it to a communication instrument package on thesurface of the ice shelf. As it moves, the profiler will measure temperature,salinity and currents from 3 meters below the ice to just above theseabed. It can also be instructed to park at specific depths and gauge waterturbulence and vertical transport of heat and salt along the water column. Thedevice will send all data to the surface tower that will then transmit it toStanton’s laboratory via a satellite phone.

The profiler is controlled remotely, and Stanton can vary its sampling rate.I
t will initially do fast sampling,to observe daily changes in water properties and circulation withinthe ocean cavity.

“After about a month of fast sampling, we’ll make it reduce the numberof profiles it takes each day, to capture seasonal changes in water propertiesand circulation,” Stanton said. “If it survives its first year, we’ll switch tosuper slow sampling, to measure how much heat is coming into the cavity everyyear.”

A second holewill support another instrument array similar to the profiler but fixed toa pole stuck to the underside of the ice shelf. The fixed-depth flux packagewill make measurements very close to the interface where ice and water exchangeheat.

Another gadget connected tothe fixed-depth package will be a string of 16 small temperaturesensors deployed within the lowermost ice to freeze in and become part of theice shelf. Their mission: to measure the vertical temperature profile,data that can tell scientists how fast heat is transmitted upwards through theice whenever hot flushes of water enter the ocean cavity.

“Since the temperature of the ice shelf determines its strength, we hypothesizethat strength may decrease as warmmelting events occur within the ocean cavity,” Stanton said.
 
Stanton plans on deploying up to two sets of instruments during this fieldseason, and a third one next year. “If we get one in, I’ll be happy. If I get two, I’ll be extraordinarily happy,”he said. One of the biggest challenges in building his pack of instruments,Stanton said, was designing it to fit the hole in the ice shelf, only 20centimeters wide and 500 meters long. A tight, long hole also means that theteam will only get one shot at deploying the instruments: once the package islowered into the ocean cavity, it cannot be pulled out.

 
“I have been deploying instruments intoice floes in the Arctic for the last 10 years, so I got quite used tojust putting them in and turning on my heels and walking away. But it’s stillquite hard to do,” Stanton said.

Explosions and sledgehammers
A geophysicist with Penn StateUniversity,
Sridhar Anandakrishnan, will create tiny earthquakes to studythe shape of the ocean cavity and the properties of the bedrock under the PIGice shelf. He will be doing measurements in about three-dozen spots in theglacier, using helicopters to hop from oneplace to another.
Anandakrishnan’s technique, formally called reflectionseismology, involves generating waves of energy by setting up small explosionsor by using instruments similar to sledgehammers to bang the ice. He’ll recordhow long it takes for the waves to travelthrough ice and water, bounce off the seabed and return, and he’ll analyze thestrength of the echo. Both factors will tell him about the thickness of the iceand water.

“[The technique] is identicalto the way bats and dolphins do echolocation: they send out a sound and listento the echo – both the time and direction of the echo tell them about thedistance to their prey,” he said.

Anandakrishnan also wants tostudy the properties of the bedrock beneath the ice.

“When glaciers are slidingover the bedrock, they do it very differently depending on whether it is roughor smooth,” he said.

Finally, the geophysicistwill inspect a mysterious ridge that runs across the ocean cavity under the icesheet. This ridge was unknown to researchers when they designed their projectin the early 2000s; it wasn’t until 2009 that an unmanned submarine operated bythe British Antarctic Survey detected it. Its existence has made the scientistsrethink where they will place their oceanographic instruments under the iceshelf, so that they don’t hit the ridge while the glacier advances toward thesea.

“ThePine Island Glacier ice shelf continues to be the place where the action istaking place in Antarctica,” Bindschadler said. “It only can beunderstood by making direct measurements, which is hard to do. We’re doing thishard science because it has to be done. The question of how and why it ismelting is even more urgent than it was when we first proposed the project overfive years ago.”

Text by Maria-José Viñas. Pine Island Glacier ice tongue image originally published on the Pine Ice Glacier Ice Shelf page. Image of Bob Bindschadler on the ice shelf originally published here. Ocean profiler image originally published on the Pine Island Oceanography Program website. Image of Sridhar Anandakrishnan originally posted by the National Science Foundation.

What to Expect from the Arctic

Posted on by .

Guest science writer KarenRomano Young reports from the ICESCAPEmission:

The U.S. Coast Guard Cutter Healy, our chunky red-and-white icebreaker, sits at the gates of the Arctic Ocean. In the wee hours this morning, the sun set and quickly rose again, and a rainbow stretched up into low clouds. The ICESCAPE mission had reached station 5 of a seven-stop transect of the Bering Strait, between Fairway Rock — resembling Kong Island, but with pointy ears — and Little Diomede (U.S.) — something like the “Cliffs of Insanity” in The Princess Bride. Close by is Big Diomede (Russia), topped with fog.

Movie references aside, this is a dramatic spot in which to find yourself when you wake up in the morning — or in the evening, as is the case for the half of the science crew working the night shift to process the samples.

It seems that no matter how many times a scientist has been to sea, it doesn’t get old. Greg Mitchell (below right), a specialist in ocean optics from the Scripps Institution of Oceanography, reckons he has spent about four years of his life aboard ships. His first trip to the Arctic was in 1987, his first year at Scripps. Mitchell’s research has taken him all over the world — to Antarctica and back again many times — but he hasn’t been inside the Arctic Circle since 1989. He expects change. Greg Mitchell

Observing the system…..and how it interacts with the edge of the sea ice…..and what’s going on with the ice melt…..and how it affects the ocean…..those principles won’t be any different than they were 20 years ago. “What we’re clearly seeing is that the sea ice is reducing more and more all the time,” said Mitchell. “This means less sunshine reflecting off the ice back into space, and more getting into the ocean.”

He expects the increase in sun-light on the sea to do three things:

  • “The light that’s not reflected will heat the ocean, accelerating the warming and accelerating the melting of the sea ice.”
  • “As the ocean warms it becomes more stratified. If you dive in a lake in the summertime, it’s warmer at the surface. But as you dive down, you feel the cold. That’s because the warm water is lighter than the cold water, and it stays at the surface. That’s thermal stratification. As you warm the ocean, it’ll stratify more and that will create a warm layer with a lot of light for algae to bloom (as long as they have nutrients).”
  • “More light in the ocean should cause more total photosynthesis in the Arctic, so we’ll lose habitat for polar bears but we’ll gain habitat for plankton.”

Like the rest of us, Mitchell is concerned about that. “I’m not saying it’s a good trade off. I think we should leave things alone. But the system’s changing, and as it changes we don’t know what the consequences of those changes will be. It’s hard to say what we could do. What we really need to do is to find a way for humans to have smaller footprint on earth. So we need to understand the processes better and then we need to model it.”

That’s why he’s here.

Mitchell, along with his group from Scripps, is involved in ground-truthing the optical properties of the Arctic Ocean (photos at the top and bottom of this post). That is, he’s helping to ensure that what they see at the surface squares up with the methods NASA satellites use to assess ocean color, an indicator of the level of chlorophyll and, by proxy, phytoplankton. NASA’s satellites measure the color of the ocean by flying over the earth and picking up blue, blue green, and green. If there’s not a lot of algae, the ocean is blue. If there is a lot of algae, the ocean is green.

But color is just one way of looking at phytoplankton levels. In order to truly assess the situation — for example how much carbon dioxide the phytoplankton are taking in – scientists need to assess the processes at work in the sea. “The optics don’t tell us this, so we have to take water samples, process the water, and then relate that to the optics we measure from the ship,” Mitchell said.

The global mapping you can see on the NASA site uses mathematical equations developed from the shipboard work. Satellite validation and calibration is based on the findings of scientists who go to sea and study the water to see what’s living there. Mitchell’s research group claims responsibility for about 20 percent of the global observations used by NASA for their models to convert satellite-measured optical measurements to chlorophyll estimates.

lowering gear from the Healy

The data contributes to models that allow prediction of primary production — the growth and health of organisms — under various conditions. Mitchell’s instruments include a small optical profiler — a fish-shaped instrument lowered from the Healy’s bow — and an optical package of instruments that measure water properties when it is lowered from the powerful A-frame at the stern.

“As ecologists, we don’t want to just know what color the ocean is,” he said. “We want to know how much plankton there is.” He walks to the edge of the ship and looks over the rail. “Now what we’re seeing out here is green water. There’s a lot of chlorophyll.” That means a strong pulse of phytoplankton, busy photosynthesizing the extra sunlight.

All photos shot by and courtesy of Karen Romano Young

Puzzling Over the Pieces

Posted on by .

Guest contributor Karen Romano Young (photo at right) blogs from NASA’s ICESCAPE expedition…

There’s a sign on the door of the room I share with Sharmila Pal and Emily Peacock. It’s a green square of plastic engraved with a picture of a polar bear and the words “SCIENCE – LATE SLEEPER.” So many of the scientists aboard Coast Guard Cutter Healy for the ICESCAPE mission are awake through the night that the ship’s engraver, Chief Warrant Officer 3 Sean Lyons, has turned out a special  edition of late sleeper signs, complete with a rocket ship for NASA. Almost every door boasts a sleeper sign of one kind or another.

The reason? Aboard ICESCAPE, the science goes on 24 hours a day. We’re on a path to the far north, steaming from station to station through the night. Sometimes we’re in ice, sometimes we’re in open ocean, sometimes there’s a mix. Sometimes, there are walruses and seals. Each group of scientists has divided their schedule into shifts, so while some are catching their zzz’s behind those “late sleeper” signs, others are awake and overseeing operations, making measurements, and processing samples.

NASA’s Stanford Hooker takes the small boat out to measure light and take water samples, away from the interference of the ship. Karen Frey’s group from Clark University works on ice stations and takes Van Veen grabs in the open sea. (It’s like a giant pooper-scooper that scoops sediment from the ocean floor).

Bob Pickart of the Woods Hole Oceanographic Institution works to assess currents and other elements of physical oceanography, such as eddies and upwelling, as we pass through the ocean. James Swift, from Scripps Institution of Oceanography, oversees the CTD, a rosette of siphons and bottles triggered to sample water at various depths. (CTD stands for conductivity, temperature, and depth.) Greg Mitchell, Rick Reynolds, and their groups from Scripps measure the ocean’s optical properties with a small profiler dropped from the bow and with the Inherent Optical Properties (IOP) package of instruments deployed from the stern.


Sketch by Karen Romano Young

“We’re all working on different pieces of the same puzzle,” Reynolds says. “It’s impossible for one group to measure all we need to know. [Chief Scientist] Kevin Arrigo’s group is looking at core pigments, the plant pigments in the water column. Others are looking at chemical analyses of the nutrients in the water. It’s a big team effort. The ice people are working in a completely different environment, but there are algae in both places.”

The $250,000 IOP suite of instruments assesses the health of the ocean by analyzing the absorption and scattering of light by particles suspended in the water, including chlorophyll-rich algae; the quantity and quality of algae (the health and growth rate); and the presence of minerals and sediment. Each instrument on the IOP contributes to a picture of the makeup of the particles by assessing changes in light transmission.

“We start at the top,” says Reynolds (shown at left). “We look at what the NASAsatellite sees — the sea color — and parse out the differentcharacteristics of the water — how much algae, and what else is there,such as minerals from rivers, re-suspended sediment (mud stirred intothe water) and melting ice.” The resulting data will help thescientists develop new algorithms — equations for solving problems –to support the satellites.

NASA ice- and ocean-observing satellites, now working for more than ten years, are beginning to allow us to examine changes in the climate. One purpose of ICESCAPE is to look at the ocean with greater detail than the satellites offer, in order to improve and refine the interpretation of the satellite data. 

“We’re here because NASA wants to know what the satellites are seeing right here at the stations,” says Reynolds, “where nobody else may sample for decades, because the ocean is so vast.”

All imagery, including the IOP sketch, courtesy of Karen Romano Young 

Plankton on Parade

Posted on by .

This is the last of four dispatches from guest writer Karen Romano Young. She spent time on the ICESCAPE expedition

The hypothesis has been proved conclusively aboard the Coast Guard Cutter Healy: I can officially sleep through anything. Yesterday [June 26] we hit what chief scientist Kevin Arrigo calls the heavy ice, northwest of Point Barrow, the northernmost point in the United States. Almost immediately we spotted a polar (right) bear, but haven’t seen one since. You can’t blame them for staying away from the Healy as it slams its 16,000 tons — plus the combined weight of everyone who spent the day eating the chocolate croissants Emily Peacock baked — into the ice.

Early this morning, the ice scientists stood on the bridge and targeted a floe for an “ice station.” For nine hours, we tried to get to it. Slowly and steadily, the ship made a path, ramming, cracking, or backing and ramming again, and the chopped-up ice in our wake soon froze together behind us. Scientist Sam Laney wishes he had a computer application that would detect seismic disturbances, saying he has lived through earthquakes registering 5.5 on the Richter scale and the vibrations didn’t feel as strong as they do right now.

[Laney commented later: “I actually downloaded a program last night and took a few hours of measurements in the aft hose reel room. I am not a seismologist, of course, but I’m estimating between 4.3 and 4.9 on the Richter scale based on these crude measurements.” This is why I like to hang out with scientists. ]

You can see the ice on a map compiled from satellite data, but the reality of the sea ice is right here at sea level. It’s quite different thing to see it in a satellite image as opposed to falling over in the shower because your ship is tilting as it climbs a ridge of jammed-together ice floes and slides back down.

The sea ice measurements made by a dozen scientists on the ice for our station will help confirm details in the satellite maps, just as the work of those studying optics in the open sea will add to the sea color (chlorophyll) mapping that NASA does.

But there is an additional method of observing the Arctic Ocean that I’d like to tell you about because it has been so exciting to everyone here at ICESCAPE. You don’t have to interpret maps or charts of data. You just have to sit back, put your feet up, and check out Sam Laney’s pictures.

Sam’s images come from a stream of water coming up through a hose at Healy’s stern. All the microscopic organisms in the stream parade in front of a camera, sitting briefly for a snapshot before returning to the sea. The instrument, which is set up deep below in the aft hose reel room, is called the Imaging FlowCytobot (below right). It was developed at the Woods Hole Oceanographic Institution.

Flow cytometry has long been used in medicine for counting cells — such as platelets – in blood samples as they are squirted past a laser. Oceanographers use flow cytometers to count the small cells that live in seawater, such as phytoplankton (photosynthetic microbes) and other small organisms. 

Imaging flow cytometry takes this approach one step further by triggering a camera every time a cell passes in front of the laser beam. Software on the imager immediately crops out the background from the picture to focus on the critter that was just photo-graphed. The revolutionary result is a steady flow of pictures of organisms as small as 2 microns living in seawater. It looks like a case of jewels: individual round-bodied gems, bigger broach-like diatoms chains (above right), and monster-like ciliates that prey on the smaller critters. 

In the past, scientists were able to gather steady flows of water and videotape the plankton at magnification. But managing this huge amount of data would have taken such incredible man-hours that it was impractical for use at sea. The Imaging FlowCytobot does it for us, snapping off a continuous stream of pictures — as many as ten thou-sand cells in a volume of seawater no bigger than a AA battery

Laney’s sea-going imager is an outgrowth of an underwater Imaging FlowCytobot that his collaborators Heidi Sosik and Rob Olson have operated for several years at the Martha’ Vineyard Coastal Observatory off Massachusetts. ICESCAPE is the first time the instrument has been used at sea to survey broad regions of the ocean.

“We are seeing what’s in the water immediately, not after the fact in a lab,” Laney explained, “so it’s obvious when the water — and what’s in it — changes. In the images taken north of Dutch Harbor, there weren’t many cells out there because it’s the open ocean. But in the Bering Strait, the jewels were much more elaborate because we were closer to shore. A large diatom chain indicates an ecosystem that has a lot of nutrients and is highly productive.”

Laney, Sosik, and Olson hope to see Imaging FlowCytobots placed aboard long-term, deep-ocean moorings in the open sea, such as those that will be deployed as part of the Ocean Observing System.

Of course, some of the fun is just seeing the plankton in action. Sometimes you can simply tell that they’re ailing or dying. In one memorable stretch of sea, off Point Lay, the Cytobot caught a stream of diatoms in the act of dividing and reproducing. Then there are the horror shots, in which a ciliate stretches its cilia toward a hapless phytoplankton.

Imagery courtesy of Karen Romano Young. The polar bear was photographed by Gert van Dijken. 

NASA Readies for Spring 2010 Ice Bridge Campaign

Posted on by .

The following is a cross-post from our sister blog at NASA’s Operation Ice Bridge. For more frequent updates on the Ice Bridge mission, visit https://www.nasa.gov/topics/earth/features/ice_bridge/index.html

Credit: John Sonntag/Wallops Flight Facility

In August 2008, NASA scientist John Sonntag, of NASA’s Wallops Flight Facility in Wallops Island, Va., captured this view of a small iceberg as it moved down the Narsarsuaq fjord in southern Greenland. “I spent about half an hour watching that little berg, which was in the process of disintegrating during the time I was watching,” Sonntag said. “It went from a complete, small berg to a collection of floating ice rubble within that small span of time. The place was so quiet that the noise of the berg softly coming apart was the only sound present.”

Sonntag’s observation took place during the 2008 NASA and Center for Remote Sensing of Ice Sheets (CReSIS) airborne deployment in Greenland. This spring, Sonntag and other scientists return to the Arctic for big picture and little picture views of the ice as part of NASA’s six-year Operation Ice Bridge mission — the largest airborne survey of Earth’s polar ice ever flown — now entering its second year. The project team is finalizing flight paths over Greenland’s ice sheet and surrounding sea ice, where scientists will collect measurements, maps and images from a suite of airborne instruments. Such information will help scientists extend the record of changes to the ice previously observed by NASA’s Ice, Cloud, and land Elevation Satellite (ICESat), while uncovering new details about land-water-ice dynamics.

NASA aircraft have made numerous science flights over Greenland, most recently during the spring 2009 Ice Bridge campaign and also in 2008 as part of the NASA/CReSIS deployment. Smaller-scale airborne surveys have been made by William Krabill, of NASA Wallops, and colleagues nearly every spring since 1991.

Visit the Operation Ice Bridge Web page throughout the spring 2010 campaign for news, images, and updates from the field. Flights from Greenland are scheduled to begin no sooner than March 22.

— Kathryn Hansen, NASA’s Earth Science News Team

The Mysteries of Muck (and the Collapse of the Laurentide Ice Sheet)

Posted on by .

Field assistants tromped through bogs in Harriman, NY to collect sediment cores that NASA
scientist Dorothy Peteet is using to date the retreat of the Laurentide Ice Sheet.  Credit: Peteet

I spent big chunks of my childhood mucking through the lakes and bogs of New England with my brothers and looking for any number of critters hidden in the silt.

Turtles, of course, were the main draw (minus the snappers, which we knew were capable of mangling a toe or finger with a passing chomp), but actually snagging one always was a rare treat. Bullfrogs, salamanders, and newts were our standard catch.

If only we’d had a microscope. Watching Goddard Institute for Space Studies (GISS) botanist Dorothy Peteet show images of tiny fragments of pollen, seeds, and fossils that settled to lake bottoms and sat largely unchanged for thousands of years reminded me of the extraordinary oddness–and beauty–that’s lurking in the most unsuspecting of places.

Look, for example, at this fossilized head shield of a daphnia, or water flea, which Peteet showed during presentations at GISS and the American Geophysical Union meeting last December. It’s a miniscule planktonic crustacean with a transparent body and a heart that beats visibly:



Or this statoblast, a peculiar little reproductive pod that can withstand desiccation and freezing and buds from aquatic creatures called bryozoans:

 

Or this one, a fossilized leaf of a fruit-bearing, cold-loving tundra plant, perhaps a blueberry:

 

Peteet isn’t poking around in the mud just for fun like my brothers and I did as kids, though. She’s collecting bog cores and scrutinizing the bits of fossilized plants and animals, which can be dated quite precisely using radiocarbon techniques, that turn up in the cores. Her goal is to pinpoint the timing of the collapse of the Laurentide Ice Sheet, a massive block of ice that stretched as far as Long Island during the peak of the last ice age. With Arctic ice currently undergoing rapid retreat, sorting out how the Laurentide Ice Sheet collapsed has big implications for understanding how climate change might proceed.

By analyzing material from some of the first creatures to colonize glacial lakes after the ice retreated, such as those water fleas, Peetet can estimate the date the ice sheet collapsed. Her findings suggests that the collapse occurred about 15,000 years ago, which would put it five-to-ten thousand years later than other dating techniques (particularly one influential technique that involves dating the beryllium from boulders dropped by the retreating ice sheet). 

“This was surprising, and it’s generated some controversy,” she told her colleagues. “I’d like to have your ideas about what’s going on.” To learn more about the topic, you can watch, listen, or view a pdf of Peetet’s full presentation here

Share your stories about exploring the muck in your neighborhood, your ideas on the dating controversy, and we’ll make sure that Peteet sees them and posts a reply.


Botanist Dorothy Peteet

                                                                                                                                                                 
–Adam Voiland, NASA’s Earth Science News Team       

An Award-Winning Scientist Who Came in from the Cold

Posted on by .


NASA-funded researcher Ben Smith digs a snow pit at a West Antarctic Ice Sheet Divide core
site to try to infer the annual rate of snowfall. Credit: Ben Smith

Researchers who study glaciers and polar dynamics often get into it for the love of the field work — the challenging terrain, technicological adventures, and thigh-deep snow.

Benjamin Smith, a researcher at the Polar Science Center at the University of Washington’s Applied Physics Laboratory, was no exception. As a fledgling physicist in the 1990s, his first summer job after college turned into an eye-opening adventure — a 3-month stint at the Kamb Ice Stream in Antarctica as a field assistant mapping buried crevasses with snow-penetrating radar. The rest, as they say, was history.

These days, Smith is enjoying a rare honor as one of two NASA-supported researchers to receive the Presidential Early Career Award for Scientists and Engineers (PECASE), awarded at a White House ceremony last month.

WhatOnEarth: Field work was your entry into studying glaciers. Are you involved  in Arctic or Antarctic field work now?

Smith: After a few years of field work, I discovered that though being out in cold is great, the quicker way to learn about glacier change is by doing remote sensing work. That requires a great deal of data analysis indoors. So with that notion, I got onboard as part of NASA’s ICESat I mission while working on my doctorate in physics.

WhatOnEarth: What work do you believe was the basis for your presidential award?

Smith: Well, I have a few projects that I’ve been fortunate enough to be involved in.

Not too long ago, I wrote a paper where we found that several lakes beneath the glaciers in Antarctica have gained or lost water in the last five years, and at a rate much faster than things usually happen in Antarctica. We’ve been seeing lakes that fill or drain in half a year. In one case, 3 cubic kilometers of water drained last year from one of these lakes. That’s about the size of Lake Washington in Seattle.

My main objective in all of this is to figure out where that water went and how it has affected other subglacial lakes and glaciers downstream. Have those glaciers sped up from the water flowing under them? The warmth of the surface bed beneath glaciers allows them to slide faster. If you add more water, there’s potential for glaciers to slide faster. 

I’m also part of a team that is helping to design the ICESat II satellite – a project we hope will build on the success of ICESat I. The satellite will boast several laser beams rather than one, so it’ll provide much better spatial coverage of the Earth’s surface to measure glacier mass and area.

 
President Obama honored PECASE awardees, including Ben Smith and Josh Willis, in January at the White House.
Credit: The White House


WhatOnEarth: Were you aware that you’d been nominated for the PECASE award?

Smith: No. I was completely unaware of it until I was notified by the FBI about a background check! I can tell you I was relieved when I found out the background check regarded my visit to the White House. I understand now that my nomination was put forward by colleagues at NASA. Somehow, my nomination came out on top of the pile, and that’s pretty cool.

To read a few of Ben Smith’s ICESat-related scientific papers, click the topics below.

Ice stream elevation changes observed by ICESat

Increased flow speed on an East Antarctic glacier

An inventory of subglacial lakes detected by ICESat

Gretchen Cook-Anderson, NASA’s Earth Science News Team