Wednesday, October 10, 2012

Drones and Marine Mammal Research

Up until recently, the use of unmanned drones has been strictly the domain of the US Military.  Recently several southern US states and the US Border Patrols have begun using them to finally better enforce our southern border.

Now the use of drones has expanded into the realm of scientific research.  The article below, from NOAA, chronicles a novel approach to marine mammal surveys in isolated areas.  The drone can be useful especially when monitoring dangerous animals.


Aerial Drones Give NOAA Scientists a New Perspective

Wayne Perryman with a group of penguins on Livingston Island in Antarctica.  
A hovering aerial drone.

Additional Information
Leopard seal on Livingston Island bares its teeth at researchers. Using a drone to get close to these aggressive predators might be a good idea. Credit: Ray Buchheit. 

October 3, 2012 
From a rare rocky outcrop on the otherwise ice-covered surface of Livingston Island, near the end of the peninsula that Antarctica extends like a tentacle toward South America, a team of scientists from NOAA's Southwest Fishery Science Center is about to launch a whole new era in marine mammal research. They just have to wait for the wind to die down.
When it does, biologist  Wayne Perryman flips a switch, and an unmanned aerial vehicle the size of a hubcap shoots straight up into the sky, its sharp insect buzz fading quickly as it races away. This drone has 6 helicopter rotors, allowing it to take off vertically and hover motionlessly, and a high-resolution digital camera. Perryman maneuvers it into position above a small group of leopard seals hauled out onto the rock, and then starts taking pictures.
Very little is known about the role of leopard seals in this ecosystem, and the drone, which Perryman also uses to study penguins and fur seals, will provide a better look. “You can tell a lot about the reproductive and nutritive condition of an animal based on its shape,” he says. From the photos, scientists can measure the length and width of individual animals and so generate estimates of their weight. By monitoring weight gain among the seals, scientists hope to better understand the energetics of the species and how they structure their ecological community through predation.
A typical season of fieldwork involves anaesthetizing a sample of animals on the ground and physically examining them. “The reason you want to work with them remotely is that it’s safer for the human and safer for the seal,” says Perryman. “A leopard seal is about a thousand pound animal, it’s mostly teeth, and it’s a very dangerous animal to work with.” They’re also particularly sensitive to anesthesia, which means that there’s a very fine line between using too much, which can be dangerous for the animal, and using too little, which can be dangerous for everyone."
Perryman served as a hydrographic surveyor in the Navy during the Vietnam War. Soon after, he joined NOAA and helped pioneer the use of aerial surveys to monitor dolphin populations in the Pacific. He’s spent most of his career working with high-end military equipment, but the digital revolution has moved consumer technology to the cutting edge. Equal parts biologist and hacker, Perryman now flies drones that are custom built out of readily available parts.
During the upcoming field season, Perryman will hand the controls of the drone to NOAA scientist Doug Krause, the lead researcher on the leopard seal study. Krause and his team will collect data both by air and on the ground, allowing them to calibrate the method for converting remote measurements into weight estimates. Although these methods are still being developed, aerial drones will soon be a standard tool in the marine mammal biologist’s field kit.
Richard Merrick, the Chief Science Advisor for NOAA Fisheries, expects drones to expand the reach of science. “Unmanned aerial systems will open the door for us to conduct research in a wider range of environments. These technologies are going to help us do this research more safely, and they are very cost-effective,” said Merrick, citing the example of remote islands where surveys from manned flights are ineffective and dangerous due to low cloud cover.
Perryman also has some ideas about where the new technology will take him, such as inside the plume of a whale as it blows. By following closely above a whale, then swooping in to sample the plume at just the right moment, a drone can yield data on hormone levels, genetic markers, and other clues to the animal’s condition. “We’ve got a technology that works really well,” Perryman says, and he and other NOAA scientists are quickly imagining new ways to use it.

Photo of a leopard seal taken from an aerial drone. Scientists use these photographs to measure the seal.

Friday, October 5, 2012

Chicken and Eggs? Isn't this oceanography?

Yes, indeed, this the an oceanography blog.  You may be wondering about the title of today's post...
What came first...the chick or the egg?

The reason I ask that qusestion is that scientists are coming closer to the mystery of the age old question..."What came first? Mollusks or their shells?"

The article below reposts back on the study results...

Which Came First, Shells or No Shells? Ancient Mollusk Tells a Contrary Story

ScienceDaily (Oct. 3, 2012) — A fossil unearthed in Great Britain may end a long-running debate about the mollusks, one of life's most diverse invertebrate groups: Which evolved first, shelled forms like clams and snails, or their shell-less, worm-like relatives?
The small new fossil, found in marine rocks along the English-Welsh border, provides the best fossil evidence yet that the simpler worm-like mollusks evolved from their more anatomically complex shelled brethren, rather than the other way around.
The discovery reinforces previous findings from molecular sequencing studies and helps clarify the evolutionary relationships of mollusks, a broad category that includes not only oysters and mussels but also slugs, squids and octopuses.
"This is a kind of missing link with a worm-like body, bearing a series of shells like those of a chiton or coat-of-mail shell," said Derek E. G. Briggs, director of the Yale Peabody Museum of Natural History and one of the paleontologists who studied the new fossil, Kulindroplax perissokomos. The researchers report their findings online Oct. 3 in the journal Nature.
The evolutionary relationships of worm-like mollusks, known as Aplacophora, has been a subject of controversy. Previously thought to be a product of the explosion of diversity during the early Cambrian period, they are now shown to have evolved probably 40-50 million years ago by losing shells like those onKulindroplax.
Kulindroplax represents the first mollusk with an unambiguous combination of valves, or exterior shells, and a worm-like body, said Mark D. Sutton of Imperial College London, the paper's lead-author.
The researchers found the specimen of Kulindroplax more than 10 years ago in the Herefordshire fossil deposit, a rich assemblage of ancient marine life forms more than 400 million years old. About 2 cm wide and 4 cm long, Kulindroplax was buried in volcanic ash deposited on the sea floor. The researchers later reconstructed its three-dimensional shape using computer software, revealing both form and structure in fine detail. In addition to its seven shells, Kulindroplax had a dense covering of spicules over the rest of the body, which it probably used to gain purchase as it crawled on the muddy sea bed.
Kulindroplax is coined from the Greek words for a cylinder and a plate, referring to the rounded body with its series of shells.
The other authors of the paper are David J. Siveter of the University of Leicester, Derek J. Siveter of the University of Oxford and Julia D. Sigwart of Queen's University, Belfast.
Support for the research was provided by the Natural Environmental Research Council.
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The above story is reprinted from materials provided byYale University.
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Journal Reference:
  1. Mark D. Sutton, Derek E. G. Briggs, David J. Siveter, Derek J. Siveter, Julia D. Sigwart. A Silurian armoured aplacophoran and implications for molluscan phylogeny. Nature, 2012; 490 (7418): 94 DOI:10.1038/nature11328
 APA

 MLA
Yale University (2012, October 3). Which came first, shells or no shells? Ancient mollusk tells a contrary story. ScienceDaily. Retrieved October 5, 2012, from http://www.sciencedaily.com­/releases/2012/10/121003132326.htm
Note: If no author is given, the source is cited instead.
Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Monday, October 1, 2012

Sea Level Rise

Throughout the contentious debates regarding climate change, one effect of these changes is sea level rise.  The article below is the most recent in a series of sobering assessments of earth's climate and sea level changes.  Of course, no one knows, really, what the future holds.  I find it hard to ignore, however, the melting of ice sheets, the disintegration of ice shelves, and the shrinking Arctic ice coverage.  It's difficult to know who to trust on this one.

Read on for more info...


Irreversible Warming Will Cause Sea Levels to Rise for Thousands of Years to Come, New Research Shows

ScienceDaily (Oct. 2, 2012) — Greenhouse gas emissions up to now have triggered an irreversible warming of Earth that will cause sea levels to rise for thousands of years to come, new research has shown.
The results come from a study, published today (Oct. 2) in IOP Publishing's journal Environmental Research Letters, which sought to model sea-level changes over millennial timescales, taking into account all of Earth's land ice and the warming of the oceans -- something which has not been done before.
The research showed that we have already committed ourselves to a sea-level rise of 1.1 metres by the year 3000 as a result of our greenhouse gas emissions up to now. This irreversible damage could be worse, depending on the route we take to mitigating our emissions.
If we were to follow the high A2 emissions scenario adopted by the Intergovernmental Panel on Climate Change (IPCC), a sea-level rise of 6.8 metres could be expected in the next thousand years. The two other IPCC scenarios analysed by the researchers, the B1 and A1B scenarios, yielded sea-level rises of 2.1 and 4.1 metres respectively.
"Ice sheets are very slow components in the climate system; they respond on time scales of thousands of years," said co-author of the study Professor Philippe Huybrechts.
"Together with the long life-time of greenhouse gases in the atmosphere, this inertia is the real poison on the climate system: anything we do now that changes the forcing in the climate system will necessarily have long consequences for the ice sheets and sea level."
In all of the scenarios that the researchers analysed, the Greenland ice sheet was responsible for more than half of the sea level rises; thermal expansion of the oceans was the second highest contributor, and the contribution of glaciers and ice was only small.
The researchers believe this is the first study to include glaciers, ice caps, the Greenland and Antarctic ice sheets and the thermal expansion of the oceans into a projection of sea-level rises. They did so by using a climate modelling system called LOVECLIM, which includes components from a number of different subsystems.
The polar ice sheets are not normally included into projections due to computational constraints, whilst researchers often find it difficult to account for the 200 000 individual glaciers that are found all over the world in very different climatic settings.
Professor Huybrechts continued: "Ultimately the current polar ice sheets store about 65 metres of equivalent sea level and if climatic warming will be severe and long-lasting all ice will eventually melt.
"Mankind should limit the concentration of greenhouse gases at the lowest possible level as soon as possible. The only realistic option is a drastic reduction of the emissions. The lower the ultimate warming will be, the less severe the ultimate consequences will be."
The researchers are from Vrije Universiteit Brussel, Manchester Metropolitan University and the Université catholique de Louvain.
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Story Source:
The above story is reprinted from materials provided byInstitute of Physics.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:
  1. H Goelzer, P Huybrechts, S C B Raper, M-F Loutre, H Goosse, T Fichefet. Millennial total sea-level commitments projected with the Earth system model of intermediate complexity LOVECLIM. Environmental Research Letters, 2012; 7 (4): 045401 DOI: 10.1088/1748-9326/7/4/045401
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 MLA
Institute of Physics (2012, October 2). Irreversible warming will cause sea levels to rise for thousands of years to come, new research shows. ScienceDaily. Retrieved October 1, 2012, from http://www.sciencedaily.com­/releases/2012/10/121001191531.htm
Note: If no author is given, the source is cited instead.
Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.