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Some Do Not Like It Hot

Geopoetry - Fri, 05/30/2014 - 14:35
 Sun et al. 2012, Science

Image: Sun et al. 2012, Science

The Great Dying, The Big One — The Permo-Triassic!
(In a time machine, not sure if that’s where I’d aim …)
As extinctions go, this one’s a blockbuster classic,
When most of Earth’s species dropped out of the game.
Conodont fossils reveal massive changes
In sea surface temperatures (and CO2?).
Terrestrial critters reduced their lat ranges;
Low-oxygen regions in deep ocean grew.
Peat swamps disappeared (a great gap in coal),
And at the equator, most fish would fry.
At times like these, seems wise to head for the pole!
In a hot-steamy world … adapt, move, or die.

_________________________________________

Further reading:

Lethally Hot Temperatures During the Early Triassic Greenhouse, Yadong Sun et al., Science, 2012

Life in the Early Triassic Ocean, David J. Bottjer, Science, 2012

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. “Some Do Not Like It Hot” first appeared on Allen’s website on Oct. 19, 2012.

Clock Is Ticking in West Antarctic

Melting Glaciers-Tracking Their Path - Fri, 05/23/2014 - 12:54
Pine Island Glacier, Antarctica

The leading edge of the floating ice tongue of the Pine Island Glacier, Antarctica. Photo: M. Wolovick

Reports that a portion of the West Antarctic Ice Sheet has begun to irretrievably collapse, threatening a 4-foot rise in sea levels over the next couple of centuries, surged through the news media last week. But many are asking if even this dramatic news will alter the policy conversation over what to do about climate change.

Glaciers like the ones that were the focus of two new studies move at, well, a glacial pace. Researchers are used to contemplating changes that happen over many thousands of years.

This time, however, we’re talking hundreds of years, perhaps — something that can be understood in comparison to recent history, a timescale of several human generations. In that time, the papers’ authors suggest, melting ice could raise sea levels enough to inundate or at least threaten the shorelines where tens of millions of people live.

“The high-resolution records that we’re getting and the high-resolution models we’re able to make now are sort of moving the questions a little bit closer into human, understandable time frames,” said Kirsty Tinto, a researcher from Lamont-Doherty Earth Observatory who has spent a decade studying the Antarctic.

“We’re still not saying things are going to happen this year or next year. But it’s easier to grasp [a couple of hundred years] than the time scales we’re used to looking at.”

The authors of two papers published last week looked at a set of glaciers that slide down into the Amundsen Sea from a huge ice sheet in West Antarctica, which researchers for years have suspected may be nearing an “unstable” state that would lead to its collapse. The West Antarctic Ice Sheet is mostly grounded on land that is below sea level (the much larger ice sheet covering East Antarctica sits mostly on land above sea level).

Advances in radar and other scanning technologies have allowed researchers to build a detailed picture of the topography underlying these glaciers, and to better understand the dynamics of how the ice behaves. Where the forward, bottom edge of the ice meets the land is called the grounding line. Friction between the ice and the land holds back the glacier, slowing its progress to the ocean. Beyond that line, however, the ice floats on the sea surface, where it is exposed to warmer ocean water that melts and thins these shelves of ice. As the ice shelves thin and lose mass, they have less ability to hold back the glacier.

What researchers are finding now is that some of these enormous glaciers have become unhinged from the land – ice has melted back from earlier grounding lines and into deeper basins, losing its anchor on the bottom, exposing more ice to the warmer ocean water and accelerating the melting.

In their paper published in Geophysical Research Letters, Eric Rignot and colleagues from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory in Pasadena, Calif., described the “rapid retreat” of several major glaciers over the past two decades, including the Pine Island, Thwaites, Haynes, Smith and Kohler glaciers.

“We find no major bed obstacle upstream of the 2011 grounding lines that would prevent further retreat of the grounding lines farther south,” they write. “We conclude that this sector of West Antarctica is undergoing a marine ice sheet instability that will significantly contribute to sea level rise in decades to come.”

The region studied holds enough ice to raise sea levels by about 4 feet (Pine Island Glacier alone covers about 62,000 square miles, larger than Florida). If the whole West Antarctic Ice Sheet were to melt, it could raise the oceans about 16 feet.

 Eric Rignot

The glaciers studied by Rignot’s research team. Red indicates areas where flow speeds have increased over the past 40 years. The darker the color, the greater the increase. The increases in flow speeds extend hundreds of miles inland. Image: Eric Rignot

In the second paper, Ian Joughlin and colleagues from the University of Washington used models to investigate whether the Thwaites and Haynes glaciers, which together are a major contributor to sea level change, were indeed on their way to collapsing. “The simulations indicate that early-stage collapse has begun,” they said. How long that would take varies with different simulations – from 200 to 900 years.

“All of our simulations show it will retreat at less than a millimeter of sea level rise per year for a couple of hundred years, and then, boom, it just starts to really go,” Joughin said in a news release from the University of Washington.

Many scientists who’ve been studying the region were already braced for the storm.

“It’s gone over the tipping point, and there’s no coming back,” said Jim Cochran, another Lamont researcher with experience in the Antarctic. “This … confirms what we’ve been thinking for quite a while.”

Cochran is principal lead investigator for Columbia University in Ice Bridge, the NASA-directed program that sends scientists to Antarctica and Greenland to study ice sheets, ice shelves and sea ice using airborne surveys. Much of the data used in the new papers came from the Ice Bridge project.

Tinto, also an Ice Bridge veteran, agreed. “I thought it was pretty exciting, because we’ve all been working on this area for a long time, and that potential for the West Antarctic Ice Sheet to behave in this way, we’ve been aware of it for a long time,” she said. “[It] made me want to get in there and look at the rest of the area, what else is going on.”

And there are still many questions about what’s going on: How fast the ocean that swirls around Antarctica is warming, how those ocean currents shift, and to what extent that is influenced by global warming.

“I have a problem with the widespread implication (in the popular press) that the West Antarctic collapse can be attributed to anthropogenic climate change,” said Mike Wolovik, a graduate researcher at Lamont-Doherty who studies ice sheet dynamics. “The marine ice sheet instability is an inherent part of ice sheet dynamics that doesn’t require any human forcing to operate. When the papers say that collapse is underway, and likely to last for several hundred years, that’s a reasonable and plausible conclusion.”

But, he said, the link between CO2 levels and the loss of ice in West Antarctica “is pretty tenuous.” The upwelling of warmer waters that melt the ice has been tied to stronger westerly winds around Antarctica, which have been linked to a stronger air pressure difference between the polar latitudes and the mid-latitudes, which have in turn been linked to global warming.

“I’m not an atmospheric scientist, so I can’t evaluate the strength of all of those linkages,” Wolovik said. “However, it’s a lot of linkages.” And that leaves a lot of room for uncertainty about what’s actually causing the collapse of the glaciers, he said.

Researchers have been discussing the theory of how marine ice sheets become unstable for many years, said Stan Jacobs, an oceanographer at Lamont-Doherty who has studied ocean currents and their impact on ice shelves for several decades.

“Some of us are a bit wary of indications that substantial new ground has been broken” by the two new papers, Jacobs said. While ocean temperatures seem to be the main cause of the West Antarctic ice retreat, there’s a lot of variability in how heat is transported around the ocean in the region, and it’s unclear what’s driving that, he said. And, he’s skeptical that modeling the system at this point can accurately predict the timing of the ice’s retreat.

But, he added, “this is one more message indicating that a substantial sea level rise from continued melting of the West Antarctic Ice Sheet could occur in the foreseeable future. In the absence of serious near-term greenhouse gas mitigation efforts, such as an escalating tax on carbon, they may well be right.”

“It starts bringing it a little closer to home,” said Tinto. “It’s a significant amount of change, but something we can start planning for. Hopefully [this will] make people stop procrastinating and start planning for it.”

Cochran agreed: The papers’ message is “that … over the next couple hundred years, there’s going to be a significant rise in sea level, and at this point we can’t stop it.” But, he added, “it doesn’t say give up on trying to cut emissions. … [Just] don’t buy land in Florida.”

____________________________________________

For further details on what’s going on in West Antarctica, check out these resources:

The two papers in question:

Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith and Kohler glaciers, West Antarctica from 1992 to 2011, E. Rignot, J. Mouginot, M. Morlighem, H. Seroussi, B. Scheuchl, Geophysical Research Letters (2014)

Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica, Ian Joughin, Benjamin E. Smith, Brooke Medley, Science (2014)

Unexpected Sisters

Geopoetry - Fri, 05/23/2014 - 09:42
 BBC Photo Library.

An artist’s rendering of the extinct Elephant bird (Aepyornis maximus), which lived in Madagascar. Aepyornis stood over 3 meters tall. Image source: BBC Photo Library.

 

An ancient island’s trove of treasure: Madagascan fauna
Tenrec, fossa, lemur, hippo, dugong, bat, iguana.
A giant bird – O, wondrous beast! – a half a ton, and tall,
Laid foot-long eggs, had beefy legs, and did not fly at all.
Another ratite, far away within the South Pacific,
The kiwi! Shy, with furry feathers, appetite terrific.
Among the old-jawed birds, you wouldn’t guess that they’re close kin,
But DNA reveals a link from deep, deep down within.
If the kiwi’s closest kin is not its moa neighbor,
Drawing up the family tree might seem a puzzling labor.
The simplest answer blows the mind – it seems that they all flew
With wings they spread across the globe, and filled in niches new.
Dinos gone (darn asteroid) left lots of open spaces,
Birds came in, diversified, flew on an as-need basis.
From this, it seems that flightlessness evolved six separate times!
The song of life, though improvised, with patterns clear it chimes.

 

______________________________________________________

Further reading:

Ancient DNA reveals elephant birds and kiwi are sister taxa and clarifies ratite bird evolution, Mitchell et al., 2014, Science.

Little kiwi, huge extinct elephant bird were birds of a feather, Reuters

The Surprising Closest Relative of the Huge Elephant Birds, National Geographic

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

Weak Underbelly

Geopoetry - Fri, 05/16/2014 - 11:44
 New York Times.

A view of the West Antarctic Ice Sheet (Landsat). Source: New York Times.

 

Antarctica’s uncertain fuse,
A “weak underbelly,” said Hughes.
Pine Island and Thwaites,
Thrown open, the gates?
As humans, what path should we choose?

The East’s held strong millions of years,
Despite cries of wolf from some peers.
West into the sea,
Up one foot, or three?
Uncertainty some meet with sneers.

Below salty waves, ice is grounded …
In this case, we see fears are founded.
In our defense,
Some centuries hence,
I hope they’ll say reason resounded.

 

__________________________________________

Further reading:

Scientists Warn of Rising Oceans From Polar Melt, Justin Gillis and Kenneth Chang, New York Times.

Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica, Joughin et al., 2014, Science.

Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith and Kohler glaciers, West Antarctica from 1992 to 2011, Rignot et al., 2014, PNAS.

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

The New World

Geopoetry - Fri, 05/09/2014 - 10:24
Archaeological expedition in the Peruvian Andes (Kurt Rademaker, University of Maine at Orono).

Archaeological expedition in the Peruvian Andes (Kurt Rademaker, University of Maine at Orono).

 

On a man in the mountains, dusk falls;

Shadows seep upward and spread.

Scaling the black, chiseled walls,

He silently seeks the dead.

 

The Andes, sharp spine of Peru,

Shelter small secrets of stone.

That night, an ancient milieu:

Obsidian, jasper, bone.

 

Into deep history, peer:

Sharp edges of tools, human craft!

Adventurous people lived here,

Climbed, feasted, laughed.

 

Archaeological expedition in the Peruvian Andes (Kurt Rademaker, UMaine)

Archaeological expedition in the Peruvian Andes (Kurt Rademaker, UMaine)

____________________________________

Further reading:

Science-2014-Gibbons-567-8 (pdf)

“New Sites Bring the Earliest Americans Out of the Shadows,” Ann Gibbons, Science, 2014

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory.

The Breathing Ocean

Geopoetry - Fri, 05/02/2014 - 11:10
 Jaccard et al. (2013) Science

Image: Jaccard et al. (2013) Science

Far south and farther south, where winds are cold and screaming,
Waters churn, and deep below, old sediments lie dreaming.
A million years’ residuum of life and death and dust,
A library of ice ages reposed upon Earth’s crust.
Very finely teased apart, this elemental tale,
On barium and opal deep into the past we sail.
With all the evidence aligned, a pattern brightly blazes:
Descent into an ice age world proceeds in two key phases.
An orchestra with many players ‘tween warm-cold inflecting;
Tiny cells, abyssal flow, great winds … now, who’s directing?

_________________________________________________

Further reading:

Two Modes of Change in Southern Ocean Productivity Over the Past Million Years, Jaccard, Hayes et al., Science, 2013

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. “The Breathing Ocean” first appeared on Allen’s website on March 22, 2013.

Hell’s Chicken

Geopoetry - Fri, 04/25/2014 - 10:00
 Mark Klingler/Carnegie Museum of Natural History

The dinosaur Anzu wyliei. Illustration: Mark Klingler/Carnegie Museum of Natural History

From our great, wild west, those rusty, dusty hills,
Bones of a beast who would give a cowboy chills.
A fierce-looking crest – a mohawk made of bone!
Claws, beak, bony tail, locked within hard stone.
Heavy as a tiger, scary yet absurd;
Anzu, feathered giant: a dino, not-quite-bird.
Mysterious, its habits – egg-eaters? A chance.
But this terrifying creature may have also eaten plants.
We piece together dreams of the verdant late Cretaceous,
Shards, broken clues from the patient and tenacious.
How I wish I could’ve seen this dinosaur humungous;
I guess I’ll have to settle for their relatives among us!

______________________________________________

NVO

© Wikipedia:NVO

A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America, PLoS One, 3/19/14

Dinosaur dubbed ‘chicken from hell’ was armed and dangerous, The Guardian, 3/19/14

National Geographic, 3/19/14

Huffington Post, 3/19/14

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. You can read more on Allen’s website.

Black Holes

Geopoetry - Fri, 04/18/2014 - 15:54
 SCIENCE VIDEOLAB

Image Credit: Science Videolab

In most observed galaxy hearts,
Massive black holes reside,
Formed from dark-baryon parts,
As huge stars collapse or collide.
Telescopes secrets divulge,
Hinting at coevolution,
The key: a galaxy’s bulge?
We do not yet know the solution.
Whence the crucial gas-fuel
With which to feed a black hole?
Do galaxies, holes often duel?
Or play a more symbiont role?
Next, we tackle all spectra;
Our tools, from low to high climb,
Sensing waves from far plectra,
Over the whole Hubble time.

__________________________________________

Further reading:

The Formation and Evolution of Massive Black Holes, M. Volonteri, Science, 2012

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. “Black Holes” first appeared on Allen’s website on Aug. 6, 2012.

Lords of the Past

Geopoetry - Fri, 04/11/2014 - 10:21
 Vassil/Alias Collections.

Paraceraurus trilobite, Ordovician, from the Volchow River, Russia. Photo: Vassil/Alias Collections.

With life, legged and finned, Earth had been teeming,
Slitherers, predators, graceful trees tall …
Now, of these species, we are only dreaming:
Glossopteris, trilobites, eurypterids, all.

Creatures of intrigue, lords of the past!
How did they grow; their color, what hue?
Why did some perish, and why did some last?
In Earth’s litholibrary, sometimes a clue.

Catastrophe beautifully carved into stone,
Graveyards ‘neath graveyards, so deep do we ply,
Silent yet eloquent, shadows of bone,
The greatest extinction, the big one – but why?

Deserts and oceans spanned latitudes wide,
Lava erupted as oceans of fire,
What means of death? It’s hard to decide:
Heat, acid, darkness, a host of things dire.

Yet from these strange ashes (if ashes they be)
Life rose up gorgeously, brilliantly new!
From lucky survivors, a vast, branching tree;
Some tendrils persisted, and weird, wild things grew!

Time is the key to death and new life,
And time can lie hidden, awaiting fresh eyes.
A haze of uncertainty, cut with a knife –
From zircon in China, chronologies rise!

To stand at the Permo-Triassic, it seems,
One faces a shockingly sharp, razor brink;
Of rapid events, the Meishan bed screams …
The “Great Dying” flew by in a mere cosmic blink.

_______________________________________________

Further reading:

An extinction in the blink of an eye, MIT News, 2/10/14

High-precision timeline for Earth’s most severe extinction, PNAS, 2014

Earth’s Greatest Killer Finally Caught, LiveScience, 12/12/13

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. You can read more on Allen’s website.

Greenland Ice

Geopoetry - Mon, 04/07/2014 - 11:13
 Christian Morel (Nature)

A Greenland ice core. Photo: Christian Morel (Nature)

If you went to Greenland, almost 80 North,
And drilled your way down … a mile, then more,
You’d find some strange layers, a story’d come forth
A record of ice ages locked in a core.
You’d find glacial ice that is clearer, more soft
Than Eemian ice (long crystals, more rigid)
And clues that the ice height was higher aloft
Than thought for that time (with air temps less frigid).
A puzzle indeed, this view down a hole –
If NEEM endured warmth, whence the sea rise?
Some question the records, some look to South Pole …
In the decades that come, are we in for surprise?

____________________________________________________

Further reading:

Greenland defied ancient warming / But Antarctic glaciers may be more vulnerable than thought, Nature (2013)

NEEM Community Members, Nature (2013)

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. “Greenland Ice” first appeared on Allen’s website on Jan. 25, 2013.

Armin Van Buuren, Ancient Wood, and Ghengis Khan: This is not your father’s field research in Mongolia

We never expected this. Enkhbat had us hovering at warp speed along the Millennium Road in the northern shadows of the Khangai Mountains. Armin Van Buuren’s A State of Trance filling our rig. We were starting a new project to study the interaction between climate, fire, and forest history in the land of Chinggis Khaan and a silky voice was lifting us higher, “and if you only knew, just how much the Sun needs you, to help him light the sky, you’d be surprised. Do…do…do.do”. We were exhilarated. The Sun was shining. This was not exactly Chinggis’ steppe. But little did we know, we would eventually be chasing his ghost.

 

Image

Byarbaatar & Amy in front of Khorgo, unknowingly about to meet Chinggis’s ghost. Photo credit: Enkhbat.

After about a day’s travel we started passing the Khorgo lava field. Amy asked, “What’s that?” Neil had forgotten about this landmark despite having walked upon it 10 years prior. It is a ~30 km2 lava field with old trees on it. Gordon Jacoby, Nicole Davi, Baatarbileg Nachin, and others had sampled in the early aughts and put together a ca 700 yr long drought record from Siberian larch. Neil relayed this information to Amy and she said that we should sample on it knowing that a 2,000 yr long record in the American Southwest had been produced on a similar landscape feature. We had a tight schedule, but as we drove out to the western edge of the Khangai’s, sampled sites, witnessed a sheep in the dying throes of a brain worm infection, got snowed on, and then sweated in much warmer temperatures, we decided it was worth the time to see what was out there. Little did we know.

By the time we arrived to start sampling, Neil was getting sick (we learned days later that Neil was coming down with tonsillitis) and we were on fumes from some bone-challenging swings in the weather. Amy pushed on during the first day with Byarbaatar and Balginnyam. The found a pile of dead horse bones and couldn’t get the chainsaw running stopping them from acquiring samples from downed, dead trees. It felt almost hopeless.

We summoned our strength the next day and explored a new section of the lava field. Soon after getting out there we starting seeing Siberian pine, a tree Neil hadn’t seen on his first visit and hadn’t been sampled previously at this site. We decided that after our fire history collection we would sample some pine trees just to see what They might have to say.

 

Image

The Logo Tree: The Siberian pine that clued us into the possibility that there might be something extraordinary on the Khorgo lava field. Photo credit: Amy Hessl

As this collection wasn’t priority, these samples sat until late January of the following year. Here is the first email of the discovery (partially redacted for some sensitive language).

 

The sample “locked in and said the inner ring i measured was 1235…whoa! that was cool b/c i started a good bit from the pith…. i race back to me scope and measuring stage…..make mistakes. going too fast. fix the mistakes…..the PITH is 1142!!!!

yes, i can see the yr Chinggis was born. i can see the yr he died. i can see the yrs Mongolia rose to rule Asia!

this has been our Holy Chinggis during the entire Mongolian project.

this is totally hot censored.

neil

ps – i guess we are going back to Khorgo, huh?”

 

Image

KLP0010a – the first sample of Siberian pine from the 2010 Khorgo lava collection to break the 1200s. The pith is 1142 CE (Common Era). Photo credit: Neil Pederson

We secured funding and we went back to Khorgo in 2012 with a bigger crew and one goal in mind – collect more wood.

We cannot believe what we have found.

For centuries, common wisdom held that the Mongols were driven to conquest because of harsh conditions – drought. Our new record, dating back with confidence to 900 CE (Common Era), indicates the opposite. After the unification of the Mongols, Chinggis Khan, you know him as Ghengis Khan, led his army from Northern China in 1211 to the Caspian Sea in 1224 CE. Our new record in PNAS indicates that it was consistently wet from 1211-1225, a period we are calling the Mongol Pluvial (look for an open access version of this paper here or contact Amy or me). No years during this period were below the long-term average, which is a singular rare run of moisture conditions in our 1,100 year long record. Independent tree-ring records over extra tropical Asia also indicate that this period was warm.

On the cool semi-arid steppe of Central Asia, water is life and in those days, water was energy. The Mongol diet is heavily based on the meat of grazers. Their mode of transportation was the short, but Pheidippidic horse. So, for food and for travel, grass is life. Grass is energy. An abundance of moisture would seem to provide the horsepower for the rapidly growing Mongol Empire. The Mongol soldier had five steed at their disposal. With a large army, that quickly translates into a huge herd and a huge need for grass.

Our tree-ring record suggests that the grasslands of central Mongolia were likely productive. They strongly agree with satellite estimates of grassland productivity. Going back in time, then, the trees would suggest the Mongol Empire during its rapid expansion was sitting in a sea of grass, a sea of energy, a potential abundance of life.

That is our hypothesis, anyhow, and something we will test in the coming years with historical documents, environmental records from lake sediments, more tree rings, and ecological modeling experiments.

While this record speaks to a rapid transformation of Eurasian culture during the 13th century, it also speaks about an abrupt transformation in Mongol culture today. Towards the end of our tree-ring record we see a prolonged drought from the end of the 20th century into the beginning of the 21st century. This drought followed the wettest century of the last 11 and occurred during the warmest period of the last 1,100 years in Asia. The abrupt transition in the environmental conditions, a transition that saw hundreds of lakes and wetlands disappear from the landscape, occurs during the transition from a more agriculturally-based economy to a more urban-based economy. These severe conditions, in combination with some harsh winters, killed millions of livestock and are thought to be one trigger of a mass migration of Mongols from the countryside into the capital of Ulaanbaatar.

 

Image

Ulaanbaatar in 2006. The homes on the far hills likely reflect climatic and economic refugees moving from the countryside into the city. Photo credit: N. Pederson

Though we cannot connect this heat drought to climate change (though maybe we kind of can), warming temperatures have stacked the deck towards higher evaporative demand, so even if the amount of precipitation remains the same, high temperatures will generate a more intense drought. That’s what we observed in the early 21st century and based on past moisture variation in Mongolia and future predictions of warming, we would expect to see similar events in the future.

From Armin Van Buuren to Chinggis Khaan to Armin Van Buuren again. We had no clue of how Summer 2010 would light the sky.*

 

_____________

 

* this post was requested by a media outlet so they could have the ‘author’s voice’ on this discovery. That version was ultimately sanitized for your protection. Here it is unadultered.

 

 


Keys to Success

Geopoetry - Fri, 03/28/2014 - 09:00

 

Jed Fuhrman, Nature 2013

Image: Jed Fuhrman, Nature 2013

 

Humans hate to catch the flu,

But here’s a fact that’s less well-known:

Bacteria get infections too

As many cultures have now shown.

In the ocean, P. ubique

(growing, growing everywhere)

Is plagued by viruses that seek

To hijack ubique’s gene hardware.

The key to beating strong predation:

Nutrients and conjugation!

__________________________________________________

Further reading:

Abundant SAR11 viruses in the ocean, Zhao et al., Nature (2013)

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 2/15/13 on Allen’s website.

Long lines and lots of instruments

Sugar - Tue, 03/25/2014 - 11:38
If you want to image the Earth’s crust and upper mantle with seismic data, you need to record the arrival of seismic waves that have propagated down to, in our case, depths of up to ~30 km.  These deep-diving phases travel quickly through the denser, higher velocity rocks of the lower crust and upper mantle, and they arrive back at the surface ahead of shallower phases at long source-receiver offsets (see video below).  




To record these lower-crustal and upper-mantle phases as “first arrivals”, where they are not obscured by the arrival of energy from shallow paths, we use long lines.  Long lines mean lots of receivers and lots of driving to deploy and recover these instruments.  We could have used lots of sources instead, but the blasts we used to get seismic energy into the lower crust and upper mantle in this experiment take a lot of time and money to setup.  Receivers are much cheaper, so we used a lot of them.  (For similar wide-angle/long-offset work at sea, airgun sources are cheaper than putting seismometers on the seafloor, so we use many shots and a smaller number of receivers out there.)


This time-lapse video shows Team 13 of 14 recovering 89 of the 1200 total short-period seismograph stations from where our line crossed Fort Benning, near the northwestern end of the line.



Nathan Miller, LDEO


Deploy in the rain, recover in the sunshine…

Sugar - Tue, 03/25/2014 - 00:32


Weather map during deployment.
When the time came to install our 1200 small seismographs across Georgia at the flagged positions, the rains came….   A lot of rain.  During our first deployment day, we received 1-2 inches of rain, and another wave of rain clouds came through on Day 2 (check out map). Roads that used to be easily passable became mudholes or were flooded with water. All-wheel-drive vehicles and drill rigs alike got stuck, and a few station locations could only be reached on foot. Our hard-working field crew labored in the rain digging holes and deploying seismometers.  Vehicles, equipment and people were covered in the famous Georgia red clay (and other muds and sands of Georgia and northernmost Florida). Adding insult to injury, problems with the programming of some of the instruments meant that we actually had to pick up and redeploy many of them. It was a mudbath.  Nonetheless, our field crew managed to deploy 1200 seismometers across Georgia by Tuesday at sundown. It was an impressive show of endurance, and an inspiring display of positivity given the number of people that were still smiling and upbeat at the end of it all. 
A couple of days later, after our seismic shots, it was already time to pick up the instruments, and the weather changed completely.  The sun shined on SW Georgia, and we picked up almost every last seismometer in just one day under blue skies….  
Donna Shillington, LDEO

Video of shots L1-05, 06, 07 and 08

Sugar - Sat, 03/22/2014 - 22:52
Shooting a land refraction experiment is more difficult in almost every way than collecting a comparable dataset at sea.  Far more difficult.  But I can't think of anything at sea that compares to the experience of setting off a series of shots at night.  On the first night of shooting, Steve, Nathan, Meghan and I detonated shots L1-05, 06, 07 and 08, while Galen, Donna and Natalie shot 14, 13, 11, and 10, and Tina, Adrian, James and Semir shot L1-04.  I recorded the video clips linked below at our shots (05-08).

To someone who hasn't seen a seismic source shot before, there really isn't a good way to describe what a good shot feels like, except as something you haven't felt before.  We had a number of students watching L1-05 being shot, since this location is quite close to Americus.  The video of L1-05 is completely lacking in drama, which is a good thing; but that shot gave us all a great ride.  The 100 pounders 06 and 07 were also surprisingly good.

We made gathers for most of the shots today. The dataset is fantastic, and 05, 06 and 07 produced super record sections.  L1-08 committed most if its energy to the air, but it shook the ground nicely and I've got a feeling those data are going to be great too.


The video is here:  http://youtu.be/DNINWj2kf1s




Dan


Sea Change

Geopoetry - Fri, 03/21/2014 - 10:06
 www.argo.ucsd.edu

Photo: www.argo.ucsd.edu

Gliders and buoys and robots — oh my!

Over and through the ocean they fly.

Oodles of data from sensors galore,

Studied by many, far from the sea’s roar.

A real revolution, there seems little doubt,

But what of the crew who never sail out?

To peer in the great briny main without drinking …

How might that impact the next wave of thinking?

___________________________________

Further reading:

A Sea Change for U.S. Oceanography, Science 2013

The New Generation of Sea Scientist, Science 2013

This is one in a series of poems based on science news, written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory. First posted 3/1/13 on Allen’s website.

Random Pictures from the Road (and otherwise)

Sugar - Wed, 03/19/2014 - 13:43
As a follow follow up to Chastity's post, I thought a few random pictures from the road would be entertaining. I have been part of group 5 and as such responsible for the part of the line that spans from Hahira in the south to just north of Adel.

 South-central part of the seismic line. The yellow line is team 5's section.  We have been in a relatively rural part of Georgia and as a result have not encountered many locals save a few who have stopped to ask if we are ok. However, we have seen quite a few interesting things that are quite out of the ordinary (to me at least).

Friendly Muscovy duck.Rocks in a stream bed with associated pink spongy material (?)
Spanish moss.Linguoid (current) ripples on a washed out road. We have also seen quite a few old abandoned farm houses in various stages of aging...



At least 10-15 dogs were standing guard at this house, including about 8 puppies.

Caroline making some new friends.
All said we have dug 122 holes in team 5's stretch. We have also helped deploy instruments in other sections as well and while doing so have seen others hard at work.

Meghan and Nate getting it done!Along the way the cars have taken quite a beating and have actually held up pretty well. Although there have been a few instances where people got stuck, I think that the people with the toughest job will be the guys that have to detail the cars upon their return...



A more appropriate vehicle (?)And lastly here's a couple more random pictures that I thought were interesting.

The large disparity in fuel grade gas prices.
A ~perfectly leveled geophone (it's harder than you'd think).Hopefully this random selection of pictures was entertaining. Up next we will post about last night's "shots." In the meantime, I can say that they were all successful with varying degrees of excitement. The most important thing is that all of our hard work is being realized as the instruments are recording refractions from buried geology that will help us unravel some of the mystery that surrounds events that happened in this area long ago.

James Gibson, LDEO

Rain, geophones, and animals … Oh my!

Sugar - Tue, 03/18/2014 - 17:15

Chastity Aiken
Georgia Institute of Technology

Flags, Flags, and More Flags - Locating the sites for 1200 instruments

Sugar - Sat, 03/15/2014 - 23:14
Many of the SUGAR field team arrived in Americus, GA on Wednesday to start helping with the massive charge of deploying 1200 seismic instruments along the SUGAR seismic line.  The seismic line spans 200 miles from northwest Georgia to just past the Georgia-Florida border; a 4+ hour car drive from end to end!  Everyone gathered early Thursday morning on the idyllic Georgia Southwestern State campus to meet with the chief scientists and learn about the proper techniques for identifying installation sites for the seismographs (just the first step in installing the instruments).  With neon orange safety jackets, numerous maps, GPS devices, packets of official permitting documents, and heads full of safety precautions the field team split into seven two-person pairs each equipped with their own squeaky clean rental car (though they didn’t stay clean for very long!).  
The fleet of SUGAR rental cars looking clean and shiny before being driven
into the field where they undoubtedly got a little mud on their tires.
Each pair of field assistants was given a segment of the seismic line to drive and flag locations for instrument installation deemed safe both from the seismograph (i.e. dry, firm soil) and the install team (i.e. a safe distance from the road).  Given the shear distance of the seismic line, teams found themselves amid diverse backdrops from rolling farmland with overly friendly cows to buzzing residential neighborhoods to sandy stretches flanked by towering groves of Ponderosa Pine trees. 
Antonio placing a flag and using a GPS device to note the location where a
seismograph will be installed amid the sandy surroundings of a Ponderosa Pine farm.
Every team was able to flag all their sites within just two days leaving us the luxury of a sunny Saturday morning free for exploring more of our beautiful Georgia surroundings.  Next up is the actual task of installing the 1200 seismographs which will involve twice the people, six more (temporarily clean) vehicles, and of course countless exciting adventures from the field.  Happy (almost) St. Patrick’s Day from Americus!
A picturesque county road near Jasper, FL along which instruments will be deployed.
-- Natalie Accardo, LDEO





A day with the seismic source team in photos

Sugar - Fri, 03/14/2014 - 23:43
The source of sound waves for the SUGAR experiment will be a series of controlled blasts along the profile.  For each of these, we drill a 60-100 ft deep hole, place emulsion explosives with boosters and caps at the base of the hole, and fill in the rest of the hole with dirt and gravel.  Each seismic source location requires a substantial amount of work by drillers and the UTEP seismic source team.  Below, Adrian Gutierrez shows a day in the life of the source team with pictures (Donna Shillington, 13 March 2014)

Adrian Gutierrez, 13 March 14
7:30 am: Leave Georgia Southwestern State University, where we are staying, and head to the site8:20 am: Arrive at site 8:30 am: Start drilling and take geological samples every 5 ft.

9:00 am: Dyno Nobel truck arrives; load emulsion into cut PVC pipe sections that serve as a holders for emulsion.
9:30 am: Surprise visit from other scientists on the project9.50 am: Setting up the booster in the emulsion.11.20 am: Loading the explosives into the drill hole12.00 pm: Drill crew starts removing their equipment12.45 pm: Tagging the charges and plugging the hole3.15 pm: Move onto the next drill site.Nighttime: Finally back to the dorm.



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