Belching dinosaurs may have helped keep their world a hot one

The world inhabited by dinosaurs was typically a hot one, with high levels of greenhouse gasses, lots of water vapor, and no permanent ice sheets. And, according to a new estimate published in the journal Current Biology, the dinosaurs themselves may have contributed to their hothouse conditions.

(Note to the editors of Current BIology: I'm not sure that the Jurassic really qualifies as "current.")

A team of British researchers has put together various estimates of the features of the Jurassic's large herbivores, such as population density, typical body mass, and so on. Combined with an estimate of how much methane is emitted by a typical herbivore, these numbers suggest that the dinosaurs were pouring out enough methane to help the greenhouse effect keep the Earth nice and toasty.

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LA smog: more cows than cars?

Much to the chagrin of California tourism promoters, smog is likely one of the things you picture when you think about the city of Los Angeles. The haze of pollutants that often hangs over the region is more than just an eyesore; it's a source of considerable respiratory stress. And where does that air pollution come from? Smokestacks, tailpipes, and cows. You read that right—cows. In fact, a new study estimates that cows contribute at least as much as automobiles.

There are two main factors that control the formation of smog. The first is the air pollution. This includes a range of volatile organic compounds, as well as oxides of nitrogen (referred to as NO_x compounds). These pollutants react in sunlight to produce the ground-level ozone that triggers asthma advisories. The second necessary condition is stagnant air. A stiff breeze moving through the city will clear away pollution before it can collect. Areas that experience smog typically have the right topographical and meteorological conditions for air masses to hang around for a while.

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Carbon storage capacity: there’s plenty, but fracking may be wrecking some

Recent changes in the Earth's climate are primarily being driven by the burning of fossil fuels—that is, taking carbon from deep in the Earth, and dumping it into the atmosphere at breakneck speed. Wouldn’t it be nice if we could just sort of… put it back?

That’s roughly the idea behind carbon capture and sequestration (CCS). Carbon dioxide is captured from the effluent of a large generator, like a coal power plant, and compressed into a supercritical liquid. That liquid is then transported via pipeline to an injection station where it’s pumped deep underground.

But the technique requires some very specific rock formations if we expect the carbon to stay there. Two new studies have looked at how much CO₂ we could hope to store, and how that storage may be affected by another process that's booming: fracking.

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Turning up the heat: windfarms lead to local nighttime warming

Relative to most other forms of energy, windfarms have a pretty minimal environmental impact, with the deaths of birds and bats generally capturing the most attention. But as a new study of their effects points out, various studies have found that turbines can modify the "transfer of energy, momentum, mass, and moisture within the atmosphere." After looking at satellite temperature data, the authors of the study conclude that all this transferring has a notable impact: areas containing wind turbines have been seeing their nighttime temperatures warm up.

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Climate change proponent realizes he was wrong, but for the wrong reasons

James Lovelock is an interesting character. He has a medical degree and has successfully designed a number of scientific instruments, but he's probably most famous for some of his big ideas, which range from specific geoengineering proposals to the Gaia concept, which proposes that the planet's geology, biology, and atmosphere interact in a complex, self-regulating system.

In recent years, his attention has turned to climate change and, unfortunately, he's largely decided to skip brushing up on science before making grandiose predictions. After having suggested that the human population on Earth would be whittled down to a handful of survivors this century, he's now backed away from these claims—and has gotten nearly as many things wrong in the process of doing so.

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Missing rocks may explain why life started playing shell games

The familiar Cambrian explosion, which started around 540 million years ago, was a game-changer for life on Earth. Bacteria (and archaea) had ruled the planet for over 3 billion years before multi-cellular animals came on the scene. When they did, they diversified rapidly (at least in terms of the span of geologic time). Though we’re right to be impressed by the sudden explosion of life, it’s not the only remarkable thing in that portion of Earth’s history.

There’s a widespread gap in the rock record immediately preceding the Cambrian explosion called the Great Unconformity. The boundary is so prominent—often separating very old igneous and metamorphic rocks from the much younger sedimentary rocks above, as is the case at the base of the Grand Canyon—that all rocks older than this are often lumped together as simply "Precambrian."

Having such a block of time missing just before the rapid Cambrian explosion has made some people suspicious that it might not have been as much of an explosion as it appears. It would be a bit like feeling confused at the climax of a story because you had skipped the setup. A new paper in Nature suggests that far from concealing the story of the Cambrian explosion, the events that created the Great Unconformity may actually explain it.

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This planet obeys the law—stats on volcanic eruptions show pattern called Benford’s Law

Scientists delight in extracting order from chaos—finding patterns in the complexity of the real world that pull back the curtain and reveal how things work. Sometimes, though, those patterns create more head-scratching than excitement. Such is the case with Benford’s law. One might expect a collection of real-world data—say, the half-lives of various isotopes, for example—to pretty much look like random numbers. And one might further expect the first (non-zero) digit of each of those numbers to also be random (i.e. just as many 2s as 9s).

Oddly, one would (in many cases) be wrong. It turns out that 1s are more likely than 2s, which are more likely than 3s, and so on. Not only that, the probabilities match a logarithmic distribution, just like the spacing on a logarithmic scale. The number 1 will be the first digit about 30 percent of the time, 2 will occur nearly 18 percent of the time, all the way on down to 9 showing up only about 5 percent of the time.

Law-abiding citizens everywhere will be happy to know our planet also obeys Benford's Law, with the duration and size of volcanic eruptions showing the same sort of pattern.

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Etc: xkcd has an image that provides a great perspective on the world’s bodies of water, along with some of the creatures that live there.

xkcd has an image that provides a great perspective on the world's bodies of water, along with some of the creatures that live there.

Read More: The cartoon

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Surprising Indonesian earthquakes set record

A pair of massive earthquakes that occurred earlier today off the coast of Indonesia, reminiscent of the tragic magnitude 9.1 quake that struck in 2004, caused a fair bit of panic but ultimately minimal damage. The earthquakes were extremely unusual, setting a new record for strike-slip faults—vertical faults where the blocks slide horizontally past each other. Most major earthquakes occur on ramp-like thrust faults associated with subduction zones, where one block is being pushed up over another.

Previously, the largest earthquakes recorded on strike-slip faults included the 1906 Great San Francisco Earthquake at roughly magnitude 7.9 and the 1855 Wairarapa earthquake in New Zealand at around 8.2. The first quake in Indonesia today was a whopping magnitude 8.6 centered about 200 miles west of the 2004 earthquake. A magnitude 8.2 aftershock followed a couple hours later another 100 miles southwest from the first. Since the movement in each earthquake was horizontal rather than vertical, no significant tsunami waves were produced.

The faults involved are related to a diffuse (that is, “fuzzy”) plate boundary between the Indian and Australian plates. A few strike-slip earthquakes have been detected there before, but they were small and scattered enough that no major fault was identified. There were certainly no indications that the boundary might produce a record-breaker.

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An open Bering Strait blocks off sudden swings in climate

You may remember 2004’s disaster movie and CGI delivery vehicle, The Day After Tomorrow. The premise of the film (which like any self-respecting disaster film, is excessively absurd) is that global warming suddenly plunges the world into the depths of an ice age. New York City drowns under the largest storm surge in history, and then flash freezes. As is the case with many disaster movies, there’s a small kernel of truth at the eye of this hurricane of exaggeration.

That kernel relates to ocean circulation and the Gulf Stream. The Gulf Stream carries warm water toward Western Europe, helping to keep it more temperate than its latitude would otherwise dictate. It depends on the downward flow of dense, salty water in the North Atlantic that drives a "conveyor belt" of ocean circulation in the Atlantic. Large amounts of fresh water discharged to the North Atlantic (from melting ice sheets, for example) can clog up that overturn by decreasing the density of the surface water. Slowing down Atlantic circulation drives down temperatures in Europe and affects climate around the globe.

During the most recent ice age, changes to the Atlantic conveyor system appear to have triggered bursts of extremely rapid climate change. A new study pins these changes on an event that took place elsewhere in the globe: the closing of the Bering Strait between Alaska and Russia.

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