[META] Test

1, 2, 3, testing.

[PHOTO] 155th Street Station, New York City

The 155th Street Station, located on the intersection of that east-west street with Eighth Avenue, marks the southern edge of the neighbourhood of Washington Heights.

[LINK] "Algal Blooms Could Have Caused Last Ice Age"

I've blogged in the past about geoengineering, the use of technology on a large scale to modify the Earth's climate. This ScienceNow report about an experiment conducted in the Antarctic Ocean suggests one possible technological project--seeding the oceans with iron dust to decrease carbon dioxide levels--might actually work, or at least, still be plausible.

Thoughts?

At various points in Earth’s history, dust fell into the ocean and fed algae, which gobbled up carbon dioxide and sank to the bottom of the sea, taking greenhouse gas with them and cooling the world. That’s a key conclusion scientists are drawing from an unusual 2004 experiment in which they grew a massive algae bloom in the Southern Ocean. Data from the experiment may also tell researchers whether seeding the seas with iron is a good way to curb global warming.

Before the 2004 study, known as EIFEX, the European Iron Fertilization Experiment, scientists had conducted 11 experiments at sea to explore how trace quantities of iron may encourage the growth of algae. Those projects had proven the first half of the so-called iron hypothesis: namely that windblown dust from land provided the trace nutrient of iron to catalyze the growth of massive algae blooms in the ancient ocean.

[. . .]

“The source and sink of carbon from glacial to interglacial periods is the holy grail of oceanography,” says oceanographer Victor Smetacek of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, who led the EIFEX expedition and was the lead author on a paper about it published online today in Nature. “It still hasn’t been found, [but] with this paper we are showing that this is probably the place to look.”

Experiments in the open ocean are by nature logistically difficult to perform, but EIFEX was particularly grueling. To grow the massive bloom, which swelled to 309 square miles, Smetacek and his team used satellite imagery to identify a 100-kilometer-wide whirlpool, known as an eddy. Within this feature, amounting to a natural beaker, the scientists released 14 tons of iron sulfate dissolved in seawater. The nutrient catalyzed the growth of a bloom that within 2 weeks was visible by satellite. Over the course of the 37-day experiment, aboard the German research vessel Polarstern, the scientists continually steamed in and out of the bloom to take measurements, weathering storms and rolling seas at 49° south of Antarctica — just between the famed latitudes known as the Roaring Forties and the Screaming Fifties.

As the bloom died and zooplankton devoured it, the researchers were able to track the sinking of waste particles beneath the surface all the way to the ocean floor. Known as “marine snow,” the particles were roughly 80 percent slime or mucus — what remains after algae cells die — 15 percent living algae, and 5 percent fecal pellets from zooplankton which had eaten the algae. In all, at least half of the total biomass of the bloom sank below a depth of 3,280 feet, presumably sequestering that carbon from the atmosphere for centuries.

Haggling over that crucial amount of flux is why the paper took so long to appear, says Smetacek, but oceanographer Ken Buesseler of the Woods Hole Oceanographic Institute in Massachusetts lauds the detailed calculations in an accompanying commentary in Nature, adding that the study “was similar to natural” algal blooms.

The EIFEX paper is “a careful scientific study” that has “refined our understanding of biogeochemical processes that influence climate,” adds John Cullen, an oceanographer with Dalhousie University in Halifax, Canada. But its confinement to an eddy and the use of iron sulfate instead of natural iron-bearing dust make it hard to know “how this experimentally induced bloom reflects natural processes.” To find that out, he says, future longer, larger-scale experiments, perhaps using natural dust, are required.

Some scientists have proposed seeding the ocean with iron to grow algae, which would capture carbon dioxide and thus help curb global warming — part of a suite of ideas known as geoengineering. Smetacek and Buesseler say experiments like EIFEX, performed on a larger scale could reveal whether this is a valid strategy. Cullen, however, has warned that such projects cannot resolve key objections to mass scale fertilization for geoengineering.

[LINK] "Scientists Discover Exoplanet Neighbor Smaller Than Earth"

Science Daily reports that a team of astronomers may have found one of the smallest exoplanets yet discovered, a molten rocky world orbiting Gliese 436, a red dwarf star also known as Ross 905 33.1 light years away in the constellation Leo. Already, it has been known since 2007 that the star supports a "hot Neptune" planet. This rocky world orbits its dim star still closer.

The exoplanet candidate called UCF 1.01, is close to its star, so close it goes around the star in 1.4 days. The planet's surface likely reaches temperatures of more than 1,000 degrees Fahrenheit. The discoverers believe that it has no atmosphere, is only two-thirds the gravity of Earth and that its surface may be volcanic or molten.

"We have found strong evidence for a very small, very hot and very close-by planet with the help of the Spitzer Space Telescope," said Kevin Stevenson, a recent Ph.D graduate from UCF and lead author of the paper, which appears online tomorrow in The Astrophysical Journal. "This discovery is a significant accomplishment for UCF."

Stevenson and his colleagues were studying a hot-Neptune exoplanet, designated GJ 436b, already known to exist around the red-dwarf star GJ 436, when data revealed clues that led them to suspect there could be at least one new planet in that system, perhaps two.

The team noticed slight dips in the amount of infrared light streaming from the star. A review of Spitzer archival data showed that the dips were periodic, suggesting that a planet might be blocking out a small fraction of light as it passed in front of GJ 436, as seen from Earth.

"I could see these faint dips in the starlight and I wanted to determine their source. I knew that if these signals were periodic, they could be from an unknown planet," said Stevenson, who is now a postdoctoral scholar at the University of Chicago.

[. . .]

With the finding of UCF-1.01, GJ 436 is likely now home to the first multi-transiting-planet system described by a mission other than Kepler. Of the 1,800 stars identified by Kepler as candidates for having planetary systems, only three are verified to contain sub-Earth size exoplanets.

The depth and duration of a transit reveals basic properties of an exoplanet, such as its size and distance from a host star. In UCF-1.01′s case, its diameter is estimated at 5,200 miles, or two-thirds that of Earth, placing the world among the smallest on record. The team also noticed hints of yet another potential planet dubbed UCF-1.02, but its period was impossible to estimate.

[LINK] "Why Doesn’t Earth Have More Water?"

Universe Today's Jason Major reports on the answer to a question that has interested astronomers examining the process of the Earth's formation: where is all the water? It turns out that, contrary to earlier expectations, the Earth did not form beyond the "snow line" of the solar system, the imaginary perimeter around the sun beyond which ices could condense out of the protoplanetary disk and so accumulate on the surfaces of young worlds, but rather within the snow line where the energy of the young Sun was sufficient to prevent Earth from becoming a true water world.

[W]hile 70% of Earth’s surface is indeed covered by water (of which 96% is salt water, hence not a drop to drink) there’s really not all that much — not when compared to the entire mass of the planet. Less than 1% of Earth is water, which seems odd to scientists because, based on conventional models of how the Solar System formed, there should have been a lot more water available in Earth’s neck of the woods when it was coming together. So the question has been floating around: why is Earth so dry?

[. . .]

A study led astrophysicists Rebecca Martin and Mario Livio of the Space Telescope Science Institute took another look at how the snow line in our solar system must have evolved, and found that, in their models, Earth was never inside the line. Instead it stayed within a warmer, drier region inside of the snow line, and away from the ice.

“Unlike the standard accretion-disk model, the snow line in our analysis never migrates inside Earth’s orbit,” Livio said. “Instead, it remains farther from the Sun than the orbit of Earth, which explains why our Earth is a dry planet. In fact, our model predicts that the other innermost planets, Mercury, Venus, and Mars, are also relatively dry. ”

The standard model states that in the early days of a protoplanetary disk’s formation ionized material within it gradually falls toward the star, drawing the icy, turbulent snow line region inward. But this model depends upon the energy of an extremely hot star fully ionizing the disk — energy that a young star, like our Sun was, just didn’t have.

“We said, wait a second, disks around young stars are not fully ionized,” Livio said. “They’re not standard disks because there just isn’t enough heat and radiation to ionize the disk.”

“Astrophysicists have known for quite a while that disks around young stellar objects are NOT standard accretion disks (namely, ones that are ionized and turbulent throughout),” added Dr. Livio in an email to Universe Today. “Disk models with dead zones have been constructed by many people for many years. For some reason, however, calculations of the evolution of the snow line largely continued to use the standard disk models.”

Without fully ionized disk, the material is not drawn inward. Instead it orbits the star, condensing gas and dust into a “dead zone” that blocks outlying material from coming any closer. Gravity compresses the dead zone material, which heats up and dries out any ices that exist immediately outside of it. Based on the team’s research it was in this dry region that Earth formed.

The press release at the Hubble telescope's website is here.

[LINK] "New Science Emboldens Long Shot Bid for Dolphin, Whale Rights"

Wired Science's Brandom Keim has a thought-provoking report examining a legal project that aims to extend the protection of the law--to some extent, human rights, even--to cetaceans.

I'm personally sympathetic to the idea, inasmuch as I suspect that consciousness is something limited to our species and that extending protections associated with consciousness to other, comparable, species is ethically sound. In the near future, I can even imagine these cases succeeding.

“The problem so far is that all nonhuman animals are seen as being legal things,” said Steven Wise, an animal law scholar and attorney. “If you’re a legal person, you have the capacity to have rights. That’s the fundamental problem we intend to attack.”

Wise founded the Nonhuman Rights Project in 2007, two years after finishing a series of books on animals, rights and law. The first two, Rattling the Cage and Drawing the Line, made a case for giving legal rights to chimpanzees and bonobos, and considering other animals on a species-by-species basis. He followed those works with Though the Heavens May Fall, an account of the 1772 trial of James Somerset, the first black human recognized as a person under British law.

At the trial’s beginning, Somerset was legally considered a thing, not even permitted to speak on his behalf. At its end, he was a person. The case used by Somerset’s lawyers was an inspiration to Wise, and by the end of 2013 the Nonhuman Rights Project plans to file two lawsuits on behalf of individual animals held in captivity in the United States.

To be sure, it will be an underdog’s battle, and might even be called quixotic. “There would be tremendous resistance. People would worry — ‘What are the limits? Is every animal in a zoo going to have a lawyer?’” said Richard Posner, a judge on the 7th U.S. Circuit Court of Appeals. “In the foreseeable future it wouldn’t have traction.”

[. . .]

Whether the Nonhuman Rights Project’s first case will involve a cetacean is yet to be determined. If personhood is defined by character rather than chromosomes, many creatures would be eligible: Great apes are intelligent, empathic and emotional, as are elephants. But perhaps the most vocal support exists for cetaceans.

“We have all the evidence to show that there is an egregious mismatch between who cetaceans are and how they are perceived and still treated by our species,” said evolutionary neurobiologist Lori Marino of Emory University during a February meeting of the American Association for the Advancement of Science. “These characteristics make it ethically inconsistent to deny the basic rights of cetaceans.”

"Some court could just say, 'Humans are special,' but there's no rational reason for it."The discussion at which Marino spoke was titled “Declaration of Rights for Cetaceans: Ethical and Policy Implications of Intelligence,” and its presence at the AAAS annual meeting, a sort of all-star game for science, signifies a sea-level change in how cetaceans are understood.

Just a few decades ago, cetacean rights would have been considered a purely sentimental rather than scientifically supportable idea. But scientifically if not yet legally, evidence is overwhelming that cetaceans are special.

At a purely neuroanatomical level, their brains are as complex as our own. Their brains are also big — and not simply because cetaceans are large. Dolphins and whales have brains that are exceptional for their size, second only to modern humans in being larger than one would expect. They also possess neurological structures that, in humans, are linked to high-level social and intellectual function.