News aggregator

‘Faux pause’

Geopoetry - Fri, 06/12/2015 - 10:30
 Maintenance workers on an ocean buoy, NOAA.

The global ocean buoy network has been expanding in recent years. Accounting for small, consistent offsets between temperatures measured by buoys and by ships reveals a greater global warming trend than previously calculated for the past 15 years. Image: Maintenance workers on an ocean buoy, NOAA.

 

New data support the conclusion

The “hiatus” was mostly illusion.

They say that the keys

Are the poles and the seas …

The next job: reduce the confusion.

 

_______________________________________________________

Further reading:

Global warming “hiatus” never happened, study says, Wendel (2015) EOS

Possible artifacts of data biases in the recent global surface warming hiatus, Karl et al. (2015) Science

This is one in a series of posts by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

MESSENGER

Geopoetry - Fri, 05/01/2015 - 12:19

 

MESSENGER's last image of Mercury. (NASA)

MESSENGER’s last image of Mercury. (NASA)

 

Alien orbits you plied,

While we vicariously spied

A distant globe …

Oh, tough little probe!

It’s been a wonderful ride.

 

 

_______________________________________________________

Further reading:

MESSENGER’s last image

This is one in a series of posts by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

An Earth Epic

Geopoetry - Fri, 04/10/2015 - 10:30
 Ricardo Ramalho

Photo: Ricardo Ramalho

I hear that the Archean Earth

Spewed lava and was hot,

(While much later, “Snowball Earth,”

Apparently was not),

Some have said that life sprung out of

Spreading-ridge-type stew,

Photosynthesis seems likely

Based on carbon records, too.

Crust was forming, oceans warming,

Stromatolites came later,

(We have to wait a long, long time

for T-Rexes, Fish, and Gators)

The Prot’rozoic was really wild,

Stromatolites went crazy,

Our atmosphere gained oxygen,

The rest is a bit hazy.

Super-duper continents

and Banded-Iron formed;

Glacial stuff beneath cap carbs

Say Earth cooled and warmed.

Half a billion years ago

Is when it gets exciting …

Suddenly, life took a leap!

All living, breeding, fighting.

Brachs and Crinoids, Bryozoans,

Weirdo shells galore,

Nautiloids (like giant dunce caps)

Roamed the ocean floor.

Then disaster strikes them down,

(This happens four more times)

And we soon approach some names

That are difficult to rhyme.

Gondwana drifts to the South Pole,

and glaciers spread like malls,

The world was likely colder,

and sea level took a fall.

So ends the years of trilobites

(and the Ordovician)

But soon we get new forms of life,

And we can all go fishin’!

Finally the land joins in,

And starts to grow green stuff,

(are you still enjoying this,

or have you had enough?)

More death, more life, more death again,

While giant mountains grow,

(we think this lowered CO2,

but no one really knows).

The Carboniferous was lush,

(that’s where our coal is from!)

Amazing bugs and dinosaurs,

(though some say they were dumb).

Gymnosperms and vertebrates,

Then the grimmest death so far,

Then Triassic life recovered,

with reptiles big as cars.

We leave aragonitic seas behind

And move towards today,

Though continents were not in place,

(that great Tethys seaway).

About 100 million years ago

Deep sea carbonates abound,

So now the ocean’s buffered well,

(and planktics can be found!)

And THEN Earth has a real bad day,

An asteroid hits hard,

Fire-balls and darkened skies,

Life is burned and charred.

(Holy cow, this is quite long,

let’s finish it already!) …

Cenozoic history

was anything but steady.

It started hot, they also say

that CO2 was high;

Wimpy mammals take the lead,

(I hear that bats could fly).

Himalayas cause a ruckus,

Gateways open/close,

We start to get some glaciers,

And cold, deep water flows.

From the Greenhouse to the Icehouse

Now we’re really getting chilly,

Then humans come along (that’s us)

and everything gets silly!

So there you have it, Earth through time,

History deep and long,

I surely skipped a lot of stuff,

And may have got some wrong.

I hope if you’re still reading

that your brain is not too vexed,

Now it’s time to face the future,

…. I wonder what is next!

 

________________________________________________________

Further reading:

See the geologic record.

This poem was first published on the author’s website on May 22, 2009.

This is one in a series of posts by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

Sunrise...Sunset...Sunrise...Sunset...

The ENAM Seismic Experiment - Sun, 04/05/2015 - 03:46
A compilation of sunrise and sunset photos aboard the R/V Endeavor. 

Day 3 sunset

Day 4 sunset

There is a bizarre foggy mist across the entire surface of the ocean.

This was a huge cargo vessel off in the distance. I know it isn't a sunrise or sunset but its a sweet pic.

Day 6 sunrise with a storm front in the distance.

Panorama of Day 6 sunrise.

Porthole sunset with my refection.

First bit of sunset color directly off the bow of the Endeavor.

about 20mins later....





Terry Cheiffetz




Go Endeavor Go! Nighttime Adventures...

The ENAM Seismic Experiment - Sun, 04/05/2015 - 02:25
A unique low light vantage point of the Endeavor

A look at all the instrumentation on the bridge of the R/V Endeavor. 

The full moon as it shines over the ocean water! Creepy!

The OBS retrieval at night! One of the crew members installed a light at the end of the hook to aid in the equipment capturing process. 


This picture was take from the bridge of the Endeavor. It is the Quantum of the Seas cruise ship at ~0300 during an OBS retrieval. 
This picture is ~2 miles away from the Quantum of the Sea cruise ship and is as close as the Endeavor can legally pass another large ocean vessel under maritime law. The bright celestial object overhead is Jupiter.

This photo shows the Endeavor docked at port just before we embarked on this high seas adventure. The first evening we went to a chinese restaurant called 7 moons. By the time we arrived back at the shipyard the gate had been pulled shut and appeared to be locked and was topped with plenty of barbed wire. After some deep thought our highly intelligent group realized that it was pulled closed and all we had to do was roll it open haha. There is a geophysicists joke embedded in that experience. 

This is the WHOI crew carefully bringing the OBS back onto the ship. Hard hats and life preservers are required when on deck during retrieval operations. The OBS in this photo is hanging down beneath the orange apparatus.  

As the Endeavor aligns itself with the OBS in the ocean currents at night the WHOI crew get in position to capture the Ocean Bottom Seismometer. 


After a successful OBS capture the WHOI crew quickly disassembles the OBS and prepares it to be stacked with the other equipment that is strongly secured to the surface of the deck. 

This shows the spotlight at night. It is used to help orient the ship alongside the OBS in the pitch black darkness of the night at sea. We have also thankfully had the full moon over the last few days to assist us in finding the OBS once it pops up to the surface.

This lovely burry image is the spot light as it tracks the OBS. The spotlight is extremely useful once the OBS is within several ship lengths of distance. 


The OBS is starting to get closer now....

Full moon over a perfect OBS recovery.

Hammock in the middle of the night!

You can really get a good feel for spotting the OBS at night in this picture. It is obviously a ship length or two off the starboard bow. 





Terry Cheiffetz







  

Survival Suits to the Rescue!

The ENAM Seismic Experiment - Sat, 04/04/2015 - 16:20
Before the R/V Endeavor embarks on its research voyage the new crew/scientists get to enjoy the challenge of a mock sinking scenario where they have ~2mins to jump out of their shoes and wiggle into these fashionable lobster costumes.  

Dr. Maureen Long and one of the crew members race each other to safety!

Graduate Student intern Colton Lynner is almost unrecognizable once the survival suit is fully on. Only the last troublesome step up zipping up to go before full emersion can take place. 

Graduate Student intern Terry Cheiffetz struggles with the final zipper step as well. 

Dr. Maggie Benoit looks like she wants to really know how to put on the survival gear in case of emergency or... she can't believe she has to participate in these fun shenanigans.


The final product appears to be both fashionable and comfortable. We would interview the model in this photo but he declined to comment....hopefully next years model will have a mouth hole haha!



Living Quarters aboard the Endeavor

The ENAM Seismic Experiment - Sat, 04/04/2015 - 04:03
This is what the state rooms look like for the research scientists on the Endeavor. That lovely extra piece of wood wedged in on the top and bottom bunks help prevent us from falling out of bed in the middle of the night if the ship rolls more than expected.


Using the restroom at sea can be challenging at times...... especially when the seas unexpectedly turn on you while you are trying to take a shower. It is basically an unexplainable balancing act.


This lovely area is where we gather for three amazing meals a day and get an opportunity to socialize with some of the various crew members aboard the ship.

Maggie has about a million movies to choose from. They are an ancient technology called VHS used a long, long time ago....


The science deck is the room where all the magic happens. Everything from running the burn sequences on the OBS's to recalculating the surfacing locations due to variable ocean currents occurs here. The amount of technology on the Endeavor is impressive.



Terry Cheiffetz





R/V Endeavor taking on water!!!

The ENAM Seismic Experiment - Sat, 04/04/2015 - 01:45
Short Video of the waves  crashing up onto the deck of the Endeavor


This 20 second video clip show just how dangerous life at sea can be! As the Endeavor rolls from one side to the next there is little to no warning as waves crash up and over onto the deck. Thankfully I was able to escape up the stairs to a somewhat dryer deck where the mist from the cresting waves and the wind were the only things able to assault my senses. The dangers out in the open on the ship at night are only multiplied by these variables.

Since the ship travels at ~10 kts between each OBS waypoint which can produce transit times as long as 12 hours and the weather isn't alway dreary the interns have a fair share of free time on the ship to explore around and lounge about.  

Checking to see if the internet wants to semi-work. I think Sampath knows he is in this picture.


Dr. Maureen Long creating a short cut to the relocated OBS equipment.


(Terry- I found two hammocks up on top of the ship perfect for some afternoon chill time haha. It also serves as a perfect vantage point when trying to find the OBS's when they reach the surface because the wave height and reflection of the sun off the water make it difficult to spot at times.)


Terry Cheiffetz


EN554 2015 Graduate Student Interns

The ENAM Seismic Experiment - Fri, 04/03/2015 - 17:24
The 2015 Graduate Interns aboard the R/V Endeavor


From left to right: Sampath Rathnavaka, Sumant Jha, Gillean Arnoux, Colton Lynner and Terry Cheiffetz.

After days of rough seas we all managed to gather up on the deck to take a group photo. The five of us are proud to be on the Research Vessel Endeavor and to finally have our sea legs. The Endeavor works around the clock out at sea and we worked in pairs on the following shift schedule, 0800-1600. 1600-2400, and 2400-0800. Each group had a PI in charge of their shift. The WHOI team was primarily in control of the extraction of the OBS in the rough seas due to the danger on deck and the sensitivity of the equipment.

The WHOI crew capturing an OBS in rough seas just prior to sunset.


Terry Cheiffetz

A high seas adventure! The ups and downs of an OBS retrieval.

The ENAM Seismic Experiment - Fri, 04/03/2015 - 14:50
April 3, 2015
EN554

A short video of an OBS retrieval on the R/V Endeavor
*WARNING* This video video contains a lot of ups, downs and what have you's. Viewing
is not recommended for the land based geoscientist!


This is a short video showing the Endeavor orienting itself alongside the OBS before the WHOI crew pulls it out of the water. It is clearly visible that both waves and weather play a major role when trying to retrieve the equipment from the ocean. 

A high resolution photo of the OBS on the starboard side of the endeavor
Sampath Rathnavaka (left) and Terry Cheiffetz (right)
Graduate student interns are excited to locate the OBS on the surface after waiting over an hour as the instrument made its transit through the water column.  


It is only a matter of time before your feet get soaking wet out on the deck. The ocean only likes to do this though if you are wearing tennis shoes instead of waterproof boots!


Its a mechanical sea turtle!


Terry Cheiffetz


Buzz Kill

Geopoetry - Fri, 03/27/2015 - 11:40
 Dave Goulson (SCIENCE)

Recent studies indicate that bees are increasingly stressed by toxins, pathogens, and lack of food. Image: Dave Goulson (Science)

 

To feed our own species, we race,

Wild herbage, corn rows replace,

The Earth’s shrinking bower:

To insects, that flower

Is not just a beautiful face.

 

________________________________________________________

Further reading:

Bee declines driven by combined stress from parasites, pesticides, and lack of flowers, Goulson et al. 2015 Science

This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

Mapping Faults Hidden below Lake Malawi

northern_malawi_new

Map of northern Lake Malawi showing major faults along the lake

The lakes along the Great African Rift Valley are among the largest fresh water lakes in the world. They lie in depressions created by slow stretching and thinning of the east African continent over millions of years. Many of the essential geological structures that enable the continent to tear and produce earthquakes are hidden within the Earth below these lakes. Lake Malawi (Nyasa) is the southernmost of these Great Rift Valley lakes and represents one of the youngest segments of the East African Rift System today. The lake is a whopping 550 km long and up to 70 km wide and surrounded by three countries : Mozambique to the southeast, Tanzania to the northeast, and Malawi to the west.

Jim Gaherty and colleagues leave port in Chipoka, Malawi aboard the R/V Ndunduma to deploy "lake" bottom seismometers

James Gaherty and colleagues leave port in Chipoka, Malawi aboard the R/V Ndunduma to deploy “lake” bottom seismometers

To image geologic structures and record earthquakes beneath northern Lake Malawi, our science team is undertaking a major “marine” seismic study as a part of the NSF-funded SEGMeNT (Study of Extension and maGmatism in Malawi aNd Tanzania) project. This part of the project involves generating sound waves using a towed array of “air guns” and recording the sound waves on a 1500-m-long cable filled with pressure sensors and an array of seismic stations deployed both onshore and on the lake bottom. The scientific and technical staff for this part of the project come from Lamont-Doherty Earth Observatory of Columbia University, Syracuse University, the Malawi Geological Survey Department, the Geological Survey of Tanzania, Aarhus University and Scripps Institution of Oceanography.

The M/V Katundu in port in Nkhata Bay, Malawi.

The M/V Katundu in port in Nkhata Bay, Malawi.

Marine seismic studies like ours are routinely done in the oceans using scientific equipment and research vessels outfitted specially for these purposes. Collecting comparable data in a great lake in Africa requires creative repurposing of available vessels and adaption of scientific equipment. To deploy and recover seismometers on the lake floor, Jim Gaherty and team used a small research vessel (R/V Ndunduma) operated by Malawi Fisheries Department. Deck space is limited, requiring efficient packing and multiple trips to deploy 34 seismometers in the lake with a boom normally used for dragging fishing nets. For the seismic imaging component, we transformed a large container ship (M/V Katundu) into a seismic research vessel. Containers were placed on the deck that house our scientific “lab,” a workshop for repairing science equipment, a storage space for extra gear and miscellaneous items, and an accommodation container with 8 bunks to sleep some of the science party. We have also added large spool for the seismic streamer, generators and compressors to drive the seismic sound source, and a large metal arm (termed “the ironing board”) for towing the seismic source. Using non-standard ships, equipment and data collection procedures requires a team with technical expertise and ingenuity, and happily we have that in spades.

We are now slowing steaming across beautiful Lake Malawi in the M/V Katundu acquiring fantastic data as we go …

Donna Shillington and Natalie Accardo, M/V Katundu, 22 March 2015

Abyssal Rhythm

Geopoetry - Fri, 03/13/2015 - 11:00
 ADAPTED BY P. HUEY/SCIENCE

When sea level drops, pressure at mid-ocean ridges decreases, which may influence the production of ocean crust. A new study suggests that the pattern of hills on the sea floor reflects the timing of sea-level change during ice age cycles. Illustration: adapted by P. Huey/Science

 

Since the dawn of mankind, I imagine we’ve gazed

In wonder and awe at the sky’s starry crown;

More recently, we have been deeply amazed

By the long-obscured, staggering view looking down

To the depths of the sea, through crust, and below

Where rock moves like taffy, dark forge of the Earth,

Great molten sculptures and stark chasms grow;

A womb steeped in intrigue, the mantle gives birth

To breath-taking mountains, and wide rolling hills,

We humans gaze down from our ships, our sea cruises

We probe this vast landscape with sound waves and drills;

From ridges of awesome proportions, crust oozes

With a rhythm, it seems, that’s tied to the sun!

Our planet’s history, scrawled on ripped pages

Of rock and of sediments, piled by the ton

Rippled and riddled with tales of ice ages;

From ridges revealed, a pattern discovered

Orbital rhythms in a seafloor slice,

The pulse of the planet, a sculpture uncovered,

Does the deep earth exhale in concert with ice?

 

_________________________________________________________

Further reading:

How climate influences sea floor topography, Conrad 2015 Science

Glacial cycles drive variations in the production of ocean crust, Crowley et al. 2015 Science

Mid-ocean ridge eruptions as a climate valve, Tolstoy 2015 Geophysical Research Letters

This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

 

The Most Astonishing Thing

Geopoetry - Fri, 02/27/2015 - 09:00
A super-massive black hole, roughly 12 billion times as massive as our sun, has been discovered at the center of a bright quasar. The light reaching us now from that distant location has been traveling for billions of years, and thus offers a glimpse into the earliest stages of the universe.

A super-massive black hole, roughly 12 billion times as massive as our sun, has been discovered at the center of a bright quasar. The light reaching us now from that distant location has been traveling for billions of years, and thus offers a glimpse into the earliest stages of the universe. Image: NASA/JPL-Caltech

 

The most astonishing thing about the universe, in my eyes,

Is not merely its gargantuan, unfathomable size,

But the way its vastness ferries gorgeous, primordial light,

So that as we look up into the night,

The farther afield our gaze penetrates, the higher we climb,

The farther we can see back in time.

Like ancient missives carefully tucked into a bottle,

Flashes of history race towards us full-throttle,

At the speed of light traversing a fabric expanding,

These waves touch our shores, and fuel our understanding

Of quasars and black holes, the light and the dark,

The Very Beginning, the bright cosmic spark

From which all this sprang – upon us, the story rains:

Of how we arose with star stuff in our veins.

 

_________________________________________________________

Further reading:

Gigantic Black Hole Discovered from the Dawn of Time, National Geographic

An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30, Wu et al. (2015) Nature

This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Department of Marine and Coastal Sciences at Rutgers University.

Exploring Antarctica by Sea, Air and Land

Peering Through Polar Ice - Mon, 12/08/2014 - 12:26
Antarctica map NASA

(Click on map for larger image)

Early winter in the Northern Hemisphere marks the start of austral summer in the Southern Hemisphere, and the beginning of the Antarctic field season. Each year, several thousand scientists head to the icy continent to take advantage of the relatively mild, though still very harsh, weather and the 24-hour daylight; the next time the sun will fall below the horizon at Antarctica’s McMurdo Station is February 20, 2015.

Lamont-Doherty Earth Observatory scientists are among the many researchers currently doing fieldwork in Antarctica. They’re leading and participating in expeditions near, above and on the continent, doing critical studies that will advance understanding of Antarctica’s land and sea processes.

Lamont biogeochemist Sonya Dyhrman is aboard an icebreaking ship, the R/V Nathaniel B. Palmer, for one month. In that time she’ll slowly travel south from Punta Arenas, Chile to research sites located off the Western Antarctic Peninsula. Dhyrman, graduate student Harriet Alexander and the other cruise scientists are investigating polar food web dynamics, with a focus on the feeding and swimming behavior of krill, a small shrimp-like crustacean. During the research cruise, Dyhrman and Alexander will collect samples of water and phytoplankton from a number of different sites. Their goal is to understand the physiological ecology of phytoplankton, which form the base of the marine food web in the Southern Ocean, and are a major source of food for krill.

 Lamont-Doherty scientists Robin Bell, Chris Bertinato, Nick Frearson, Winnie Chu and Tej Dhakal with IcePod.

Lamont-Doherty scientists Robin Bell, Chris Bertinato, Nick Frearson, Winnie Chu and Tej Dhakal with IcePod.

More than two thousand miles south, six scientists from Lamont’s Polar Geophysics Group are at McMurdo Station, a U.S. Antarctic research center located on Ross Island. They’re deploying an ice imaging system, known as IcePod, which consists of ice-penetrating radar, infrared and visible cameras, a laser altimeter and other data-collection instruments. IcePod attaches to a New York Air National Guard LC-130 aircraft and measures, in detail, the ice surface and the ice bed; important data that enables the scientists to track changes in ice sheets and glaciers.

The scientists are testing the instrumentation and training the New York Air National Guard in the deployment and operation of the instrument; this is the first time IcePod is being used in Antarctica. After the testing and training, IcePod will be operated in up to 15 other flights for routine data collection.

Also at McMurdo Station are Lamont geologists Sidney Hemming and Trevor Williams. The two scientists and their colleagues Kathy Licht and Peter Braddock will soon fly to a field site in the remote Thomas Hills, near the Weddell Sea in the Atlantic sector of Antarctica. There they’ll spend four weeks making observations and collecting rock samples from the exposed tills on the edge of the massive Foundation Ice Stream, as well as from the Stephenson Bastion and Whichaway Nunataks.

Lamont-Doherty's Trevor Williams and Sidney Hemming (left), with colleagues Kathy Licht and Peter Braddock.

Lamont-Doherty’s Trevor Williams and Sidney Hemming (left), with colleagues Kathy Licht and Peter Braddock.

The group is examining how ice sheets in the Weddell Sea embayment will respond to changing climate, specifically how Antarctic ice retreats and which parts of the ice sheet are most prone to retreat. Understanding the behavior of the Antarctic ice sheets and ice streams provides critical information about climate change and future sea level rise.

Thanks to the Internet and the scientists’ dedication to outreach, it’s possible to join their Antarctic expeditions without donning extreme cold weather gear. Follow the Dyhrman’s cruise activities on Twitter via @DyhrmanLab and #TeamDyhrman, and learn more about their research on the cruise website.

The IcePod team is blogging about their fieldwork on State of the Planet, and updates from the Lamont geologists in the Thomas Hills can be found on Twitter via @Trevor_On_Ice and #AntarcticaG297.

 

A Texas-Sized Block of Ice…

Peering Through Polar Ice - Thu, 12/04/2014 - 22:20
Icepod flying over the Antarctic ice towards Mt. Erebus (photo W. Chu)

Icepod and the LC-130 flying over the Antarctic ice towards Mt. Erebus. Photo: W. Chu

The first dedicated Antarctic Icepod mission was flown out across the center of the Ross Ice Shelf. Ice shelves are thick floating extensions of the ice sheet that form as the ice flows off the continent and into the surrounding ocean. These are critical ice features in Antarctica, bounding a full 44 percent of her coastline, where they serve as a buttress to slow the ice movement off the continent into the ocean.

Icepod flying over the front of the Ross Ice Shelf. Along the shelf edge sections of thinner sea ice appear grey on the water surface. (Photo W. Chu)

Icepod flying over the front of the Ross Ice Shelf. Along the shelf edge sections of thinner sea ice appear grey on the water surface. Photo: W. Chu

The Ross Ice Shelf is the largest of the Antarctic ice shelves, measuring just under the size of the state of Texas. It is several hundred meters thick, although most of this is below the water surface. Along the ~ 600 kilometer front edge of the shelf, the ice towers up to 50 meters in height; a sheer vertical wall of white and the iridescent blue of compressed ice. 

The goal of the six-and-a-half-hour mission was to test how the Icepod could image the varying processes at the base of the ice shelf and how well the gravimeter would work flying 90m/sec.

Sea ice covers much of the polar oceans both in the Arctic and Antarctic during the winter months.  Unlike the ice sheet which forms over land, sea ice freezes directly on the surface of the ocean when the temperature is cold enough. It influences our Earth's climate, and holds a critical place in the food web in these regions.

Sea ice covers much of the polar oceans both in the Arctic and Antarctic during the winter months. Unlike the ice sheet, which forms over land, sea ice freezes directly on the surface of the ocean when the temperature is cold enough. Sea ice influences our Earth’s climate, and holds a critical place in the food web in these regions. Photo: W. Chu

The gravimeter is a new addition to the Icepod suite of instruments. Housed separately inside the plane, the gravimeter requires a very stable platform. The instrument will be critical for determining the water depth beneath the Ross Ice Shelf, the least explored piece of ocean floor on our planet. The plan was to cross the front of the ice shelf towards Roosevelt Island, then fly inland until the plane crossed the J9 site where the first hole through the ice shelf was drilled in the early 1970s as part of the Ross Ice Shelf Project (RISP). Icepod would then fly back toward McMurdo along a line where there are plans for another science project to drill next year.

Roosevelt Island in the Ross Ice Shelf, Antarctica (Image from NSIDC)

High resolution satellite image of Roosevelt Island in the Ross Ice Shelf, Antarctica. Floating ice appears flat and smooth like the ice in this image from NSIDC.

The collected radar data showed remarkable variability over the ice. Crossing over Roosevelt Island, the change from floating shelf ice to marginal crevasses (deep cuts or openings in the ice) to ice sitting directly on the bedrock was imaged. The variation in the reflection from the bottom of the ice probably represented the different processes occurring at the ice sheet base. In some places there was evidence of ice being added to the bottom of the shelf.

When the RISP team, which included Lamont’s Stan Jacobs, drilled through J9 in the 1970s, they found refrozen ice with a structure that resembled waffles. That team also captured pictures of fish beneath the ice shelf, demonstrating that the area below was not the wasteland that it was originally believed to be. Icepod overflew the best fishing hole on the Ross Ice Shelf while the team looked at the pictures of the bright-eyed fish in the Science paper, and smiled. It is almost 50 years later, and while we have a much better understanding of Antarctica, there remains so much that is unexplored.

Icepod and the LC-130 returned to Willie Field and began immediately to plan for the next flight.

The LC-130 sitting on the ice runway (Credit N. Frearson)

The LC-130 sitting on the ice runway. Photo: N. Frearson

For more on the IcePod project: http://www.ldeo.columbia.edu/res/pi/icepod/

 

Why are Past Surface Temperatures and CO2 Concentrations Important?

The Climate Epoch - Wed, 11/26/2014 - 14:36

This blog is an outgrowth of my own research examining the past temperature of Earth’s surface and the relationship of temperature to the Earth’s carbon system. I became interested in the scientific aspects of this work as a geology undergraduate, staring at regular layers of rocks in the countryside of central Italy, back and forth, dark and light. These layers were related to past oscillations of the climate, warmer and cooler, related to long-term changes in the incoming solar radiation entering our planet from the sun. Such changes are small, but positive and negative feedbacks in the Earth system interact to translate the small changes into the radically layered rocks we see in outcrops. This was the start of a journey of discovery that continues to this day and is the foundation of my research at the Lamont-Doherty Earth Observatory.

Oscillating limestone rock layers, Italian Alps

Oscillating limestone rock layers, Italian Alps. Photo: Kelsey Dyez

How does the carbon dioxide (CO2) content of the atmosphere influence climate? This question was first seriously considered in the mid- to late-1800s, amid an accelerating, newfound interest in the natural sciences on the European continent. Specifically, the Victorians were fascinated by looking backward in time, at periodic extreme cold spells, also known as ice ages, when glaciers as tall as skyscrapers covered vast areas of land that today are free from ice.

The discourse about past climates began with this approach, through a discussion about how the driving forces in the Earth system might have caused our globe to periodically enter and exit the ice ages. Many factors, including emissions from volcanoes, the rearrangement of continents, the evolution of plants and vegetation, solar sun-spot cycles, and even asteroid impacts can and do impact the average surface temperature of the planet.

Yet time and again scientists returned to the role that greenhouse gases, and specifically carbon dioxide (CO2), play in the climate system. CO2 molecules in the atmosphere absorb heat (infrared radiation) coming from the Earth’s surface and then re-radiate some of that heat back to the surface to generate a warming effect. How is this related to the glacial ice age cycles of the past?

 CO2 molecules in the atmosphere absorb heat coming from Earth's surface and re-radiate some of that heat back to the surface to generate a warming effect

Simplified greenhouse effect: CO2 molecules in the atmosphere absorb heat coming from Earth’s surface and re-radiate some of that heat back to the surface to generate a warming effect.

One way to think about this problem is to imagine the Earth system as a huge, naturally occurring experiment (though the sample size by most experimental standards is low). Sometimes the Earth has been warmer than today, even ice-free at the poles. When the ice melts, sea level rises, continents spring back after being depressed by the weight of the ice, and plants that need warmer weather expand their habitat pole-ward. The Earth has also been cooler than today, most recently at the last glacial maximum (~20 thousand years ago) when more ice was locked up in the polar ice sheets rather than in the ocean, making for lower sea level, which exposed more of what is today the ocean floor.

Today the framework of thought has turned around, so that instead of looking back through time to understand the climate of the past, we also try to learn lessons from the past to further our understanding of the climate of the future. By burning fossil fuels for heating, electricity, transportation and other purposes, humans add CO2 to the atmosphere. Yet, by comparing ways in which the Earth’s temperature, CO2 concentration, sea level and ice sheets have changed in the past, we are able to learn valuable lessons about the climate system of today and tomorrow. You can share in this adventure here.

NYC emitted 54 million tons of CO2 in 2010

New York City emitted over 54 million tons of CO2 in the year 2010. To imagine this number, every sphere here represents 1 ton of CO2 at the average surface temperature and pressure. Image: Carbon Visuals/Flickr

One last word of caution: At the turn of the last century, people also began to wonder if land-use and manufacturing—human-induced variability—could play a role in climate. Because this issue has become highly politicized, I won’t get into all the back-and-forth arguments here. That forum has other locations online. However, for a modern history of this fascinating topic, check out the American Institute of Physics (which can be found at http://www.aip.org/history/climate/co2.htm); and for more on the science, check out what the EPA has to say (http://www.epa.gov/climatechange/ghgemissions/gases/co2.html). Both purport an objective analysis of both the history and basic science involved.

This Bird Flies South for the Winter

Peering Through Polar Ice - Mon, 11/24/2014 - 22:39
Skier 95 with IcePod visible beneath the rear window lands on the Antarctic ice. (photo R. Bell)

Skier 95 with IcePod visible beneath the rear emergency door lands on the Antarctic ice. Photo: R. Bell

Migrating south in the winter is a behavior that Antarctic scientists share with many species of birds, although the scientists fly just a bit further south. For the IcePod team, it was time to join the migration so they could test their equipment in the most challenging environment the Earth has to offer. After three “equipment shake down” trips to Greenland over the last two years, 20 hours of flight time have been set aside for flights in Antarctica, part of the final hurdle in the commissioning of the pod.

The team arrived early this month at McMurdo Base on a large C-17 to –14°F weather and beautiful clear blue sky as the plane touched down on the Pegasus Blue Ice Runway. The first few days were spent in training for everything from driving trucks in the cold to being environmentally sensitive to the Antarctic microbes to a crash course on interpreting the complex way trash is handled in Antarctica — an impressive 60 percent of everything is recycled. 

Loading the gravity meter on loan from the Kiwi for the Antarctic test flights. (Photo R. Bell)

Loading the gravity meter on loan from the Kiwi for the Antarctic test flights. Photo: R. Bell

The gear arrived soon after the team… first the gravity meter, borrowed from New Zealand, wrapped in a warm, manly pinkish quilt. With many boxes being stacked in the aircraft, the color was selected for its high visibility to assist with quick location and unloading. The IcePod and the equipment rack had paused on their trip down in Pago Pago, arriving a few days after the rest of the gear, but it was all quickly set up and humming in a bright yellow and blue rack tent next to the Willy Airfield on the Ross Ice Shelf. While waiting to fly, a GPS was installed on top of the tent, and equipment was set up to test performance. Both the GPS and the gravity meter measured the movement of the ice shelf as it shifted up and down on the tide ~ 1 meter a day. In addition to the rhythmic up/down movement, the tent, the airfield and the ice shelf are all moving northwards at 30 cm or 1 foot a day.

Scott Brown, Tej Dhakal and Winnie Chu prepare the equipment for take off. (photo R. Bell)

Scott Brown, Tej Dhakal and Winnie Chu prepare the equipment for take off. Photo: R. Bell

Finally, IcePod was cleared to fly and complete her first Antarctic survey mission installed on a Pole Tanker mission flying on Skier 95. The flight was delayed as the C-17 practiced airdrops over the South Pole runway, but as soon as the C-17 was out of the way, icePod took off and headed south.

Icepod flies over the Antarctic ice with Mt. Erebus visible in the background. (Photo R. Bell)

Icepod flies over the Antarctic ice with Mt. Erebus visible in the background. Photo: R. Bell

Low elevation data was collected on the way out to make sure the C-17 was clear. All the instruments worked in the flight across the very flat Ross Ice Shelf, then over the Transantarctic Mountains and across the spectacular East Antarctic Ice Sheet.

IcePod team at South Pole (left to right) Scott Brown, Chris Bertinato, Tej Dhakal, unidentified, Winnie Chu (photo by R. Bell)

IcePod team at South Pole (left to right) Scott Brown, Chris Bertinato, Tej Dhakal, a new Antarctic colleague, Winnie Chu. Photo: R. Bell

The low angle of the sun made the mountains, crevasses and wind scour areas stand out beautifully in the imagery. The deep radar imaged the structure of the Ross Ice Shelf even from 21,000 feet. The infra-red camera showed the variable temperature of the different types of ice in the Beardmore Glacier and the high plateau. The gravity meter that had rolled in on the speed pallet was extremely stable. At the South Pole, Skier 95 offloaded fuel while the IcePod team made a quick trip to the actual pole.

The flight was a success – data collected on an opportune flight and fuel delivered.

For more on the IcePod project: http://www.ldeo.columbia.edu/res/pi/icepod/

 

Demob!

The ENAM Seismic Experiment - Wed, 10/22/2014 - 12:11

After five days in North Carolina we have recovered all of the 80 stations. The stations have been recording for one month along two profiles. Now we are downloading the data at the instrument center at the East Carolina University in Greenville.  The last step is getting the equipment ready for shipping back to PASSCAL in New Mexico.


Beatrice (Bix), Dan and Ana working onsite at the first station recovered. Bix and Ana are checking the parameters of the Reftek with the CLIE, and Dan is saving the GPS waypoint of the recovery site.



Yanjun working on one of the stations recovered on the north line. He is performing a check with the CLIE to see the number of events recorded, the data stored on the disks and stopping the acquisition. He also checks all 3 channels on the L28 sensor. Once the acquisition has been stopped, the sensor can be pulled and the station is taken back to the instrument center.



A few of the Refteks at the instrument center. The upward cap indicates that the data have been downloaded.



Yanjun labeling Reftek flash cards that contain recordings from the past month.



Flash cards labeled with Reftek serial numbers. This is the product of our hard labor!

Being a scientist rocks!

The ENAM Seismic Experiment - Wed, 10/22/2014 - 11:57

We experienced wonderful weather during the past week working in North Carolina. The scenic countryside is filled with tobacco fields, cotton fields, and other crops. One lucky recovery team started the first day on Kitty Hawk Beach demobilizing site 101.


Beach near the easternmost station on the north line of the onshore profiles




One of the many cotton fields in the eastern North Carolina coastal plain

Pages

 

Subscribe to Lamont-Doherty Earth Observatory aggregator