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Watching lava fight with snow in Kamchatka

Depending on the context, volcanic eruptions are either terrifying or transfixing—sometimes both, but rarely neither. The opportunity to safely view the otherworldly spectacle of lava rarely fails to ignite a child-like, giddy wonder. The damage currently being done by a lava flows in the Cape Verde Islands, on the other hand, is heart-breaking.

We study these things because they are both lovely and terrible. We want to see a lava flow spill across a snowfield out of curiosity, and we want to better understand the hazards surrounding snow-capped volcanoes out of caution. Benjamin Edwards of Dickinson College and Alexander Belousov and Marina Belousova of Russia’s Institute of Volcanology and Seismology got the opportunity to witness one of these events last year in Russia’s Kamchatka Peninsula. For nine months, Tolbachik spewed basaltic lava flows that ultimately covered 40 square kilometers, reaching as far as 17 kilometers from their source.

The lava flows came in two flavors, known to geologists by Hawaiian names. (While frozen Kamchatka doesn’t exactly evoke coconuts and grass skirts, these lavas are similar to those of the Hawaiian volcanoes.) First there’s ‘a’a (pronounced as a staccato “AH-ah”), which ends up a chunky, blocky crumble of basalt. The other is pahoehoe (roughly “puh-HOY-hoy”, which is how volcanologists answer the phone), which flows more like thick batter and can solidify into a surface resembling a pile of ropes.

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Record of past warming event shows carbon was emitted fast—and twice

Periods of rapid change are among the most interesting things in the geologic record, but that rapidity also makes them hard to study. While 10,000 years sounds like an eternity to us, it’s just a blip in the humbling expanse of Earth’s history. The stories that rocks can tell usually cover too much time to reveal all the details of a blip that short, which challenges geologists’ detective skills.

The Paleocene-Eocene Thermal Maximum (PETM to its friends) occurred about 10 million years after the extinction of the dinosaurs and 56 million years before the present. It involved the addition of enough carbon to Earth’s atmosphere to cause 5-8°C of global warming, which lasted almost 200,000 years. That caused a considerable amount of change in the biosphere, including a mass extinction among a group of bottom-dwelling marine organisms. Given that we’re also messing with the climate system today, we have good reason to be curious about the warming of the PETM.

This is too far in the past for ice cores to help us out, so our evidence comes in the form of carbon isotopes in rocks, which preserve the isotopic signature of carbon in atmospheric CO2 back then. That isotopic signature suddenly made a large jump at the start of the PETM and stayed there for the duration. Because the jump is so radical, many researchers think that sources of methane (which have isotopic signatures much different from most atmospheric CO2 carbon) are likely to be the culprits. But how rapid was the jump? Many records can’t tell us much about that—it happened so quickly that it just looks like a step change. Some estimates put it at 20,000 years, while others indicate that it could have been much shorter.

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Emit some CO2? Its warming influence should peak in about a decade

The time frames of climate change challenge us in a number of ways. For one thing, it’s difficult to personally experience changes in climate in an obvious and reliable way. (Our sense and memories are a little less precise than thermometers.) And it’s hard to feel a sense of urgency about something changing gradually, especially when the benefits of dealing with it also accrue gradually. Imagine convincing a four-year-old that cleaning his or her room would be a worthwhile investment of Saturday mornings if you had to add “but it’s going to take a couple years before you’ll notice a difference.” You might as well be pitching the joys of early bedtimes and adventurous diets.

If you believe you won’t live to see the benefits of any cuts made in greenhouse gas emissions today, a selfish case for action is harder to make. So will any of us see any difference as a result of cutbacks in emissions?

A popular 2010 post on the SkepticalScience.com website approached this question from the opposite direction, presenting an estimate for how long it takes to realize the warming from emitted CO2. Largely because the ocean takes up heat slowly, the full force of that greenhouse warming isn’t felt immediately. That post threw out 40 years as an estimate for the lag between emissions and perceptible warming, based on a 1985 paper’s calculation for the time to reach 60 percent of the long-term warming. However, that number was based on a scenario in which CO2 increases and then stays constant.

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Why are some Antarctic ice shelves feeling warmer than others?

In terms of remoteness, Antarctica has got most places on this planet beat. Climate data from the frozen continent are mostly hard-won. So while we know that warmer seawater below ice shelves has played a big role in the tremendous loss of glacial ice behind them, working out exactly why that water has warmed as much as it has is a challenge.

To that end, Sunke Schmidtko, Karen Heywood, Andrew Thompson, and Shigeru Aoki compiled all the available ocean measurements back to 1975, spanning seven databases. That enables them to pick out some longer-term trends and spatial patterns all the way around Antarctica, which hasn’t been done before. Measurements prior to the 1990s are pretty sparse, but some interesting things stand out nonetheless.

Ice shelves are the floating, leading edge of glaciers that flow into the ocean, and many act to hold back their glaciers. So while melting a floating ice shelf doesn’t directly affect sea level, it can hasten the loss of land ice, which does.

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US natural gas production could peak in 2020

There’s no question that shale gas production—enabled by hydraulic fracturing techniques—has boomed in the US with major effects on the energy industry. The price of natural gas fell and cleaner, more efficient gas-burning power plants have sprung up to usurp old coal plants. This has been seen as a long-term shift in the fossil fuel landscape, but it can’t last forever. The obvious question is just how much shale gas is down there to be had?

The most recent outlook from the US Energy Information Administration saw US production slowing from the exponential trajectory of the 2000s, but still increasing through 2040. A news article appearing in the journal Nature this week highlights a major research project run by a group at the University of Texas at Austin that foresees much lower production. Their analysis forecasts peak shale gas production in 2020, falling to half the EIA’s estimate by 2030.

The reason for the difference is mostly a matter of resolution, according to the Nature story. The EIA has relied on county-level production statistics, while the UT-Austin researchers have drilled down to one mile resolution. That makes it easier to account for “sweet spots”—the portions of a shale layer with the physical characteristics most conducive to producing natural gas. The reason for fracturing these rocks to free the gas is that they’re too impermeable for the gas to move through them, so this isn’t a case of the first few wells bleeding the store dry. But to the extent that sweet spots can be identified, they’re typically targeted for drilling first. That means that subsequent wells in the area may be significantly less productive. And that could translate into the end of the shale gas revolution arriving well ahead of schedule.

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Nature expands access to papers in its family of journals

Paywalls are the familiar enemy of the curious science seeker, frustrating most attempts to access papers published in peer-reviewed journals if you’re not at a university or library with a subscription. Talk of pushing for open access has been lively lately, with journals starting to expand dedicated open access journals and the US government ensuring that most papers resulting from federally funded research will be made open within a year of publication.

Monday saw an interesting announcement from heavyweight Nature, which is creating a new avenue of limited but greater access to papers in the Nature Publishing Group family (which includes Nature Geoscience, Nature Genetics, and many others). Actually, it’s a pair of new avenues. Both take advantage of ReadCube, an alternative reader to traditional PDFs that Nature has long hosted (and in which Macmillan Science and Education, Nature Publishing Group’s parent company, has “a majority investment”).

First, those with subscriptions to Nature’s journals will be able to share unique links to papers that will allow the user to view them in ReadCube—but not download or print them. Researchers are generally allowed to post PDFs of their manuscripts (sans print formatting) six months after a paper is published. This way, they should be able to provide links to their papers immediately. (The six-month manuscript rule will remain in effect.) That access will look like this.

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Better than shade: Rooftop material sheds heat into space

Transforming our electricity generation to renewable sources is rightly the focus of most discussions about the future of energy, but the greenest kilowatt-hour is the one not used in the first place. Yes, there are all kinds of ways to reduce energy consumption, and smarter building designs that do more with less are among those. But buildings use a tremendous amount of electricity to shield us from the summer heat via energy-hogging air conditioning systems. What if we could get some of that cooling for free?

“Passive” heating and cooling is a common approach in green buildings; approaches include things like shading windows from summer sun and floors that absorb and store solar heat in the winter. One new, clever idea is a little more ambitious: just dump some of the summer warmth back out into space.

Using rockets for this is probably out, practically speaking, so the main problem with this approach is that the atmosphere is in the way, and it will absorb many convenient wavelengths. But if you radiate the heat, there’s a small window between the infrared wavelengths of 8 to 13 microns where the atmosphere is transparent. Prototype devices have been built capable of shedding a building’s heat by emitting it in that window. But they can only work at night; during the day, they heat up in the sun, eliminating their ability to reduce the temperature of the building below the outside air temperature. Of course, it’s during the middle of the day that cooling is needed most, so that’s a deal-breaker.

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Researchers rule out a “tectonic aneurysm” in the Himalayas

If you really think about it, a great many things go into a painting. There’s the artist’s vision, sure, but there’s also the pigments and properties of the paint, the mixing of the paints on the palette, the canvas and frame, the types of brushes used, and the physical skill of the painter. Landscapes, likewise, are determined by many factors (even if they never appear in a painting). But for landscapes, a complex system of factors interacts dynamically, continually evolving and producing a masterpiece every step of the way.

The Himalayas are an astoundingly grand landscape; we call them “the roof of the world.” You could simply describe them as the crumpled product of the collision between the Indian and Eurasian tectonic plates, but that would be about as bland as describing the contents of the Louvre as “paint.” Each peak and valley has been slowly sculpted by a collaboration of geologic processes. Researchers have recently uncovered evidence about one of these processes, something with the inartistic name of "tectonic aneurysm."

Floating peaks

It’s reasonable to assume that, in a place like the Himalayas, tectonics pushes a mountain up even as erosion shaves it down. The faster the mountain pushes upward, the harder erosion works to keep it in check. That's because the peaks extend into colder elevations where ice can wedge apart cracks or form rock-grinding glaciers and steepening slopes that drive faster-flowing streams.

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More detailed paleoclimate records, brought to you by lasers

There are a number of ways that nature has preserved climatic clues providing crude telescopes to view Earth’s past. Whether it’s plankton, pollen, or glacial ice, however, the images we see are fuzzy. Some represent summer conditions more than winter. Some can be distorted by shifting winds or ocean currents. All have some limit to their magnification—showing, at best, the average of a year, a century, or a millennium.

The different temporal resolutions come from the rate at which the record accumulates information. A centimeter of ice in an ice core might have come from just one year’s snowfall, while one centimeter of seafloor sediment might have taken a century to pile up. But another part of the limitation comes from how much of the sample we need to use to generate one data point. Now, some researchers have figured out how to get a lot more out of less sample.

Cut to the core

When an ocean sediment core is brought up, it’s usually split in half. One half will be sent into storage for future study, and the other will be carved up into little chunks and bagged for different physical and chemical analyses.

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One of world’s largest landslide deposits discovered in Utah

The Markagrunt gravity slide in Utah includes most of the area between Beaver, Cedar City, and Panguitch.

Some things can be too big to notice, as our flat-Earth-believing ancestors can attest, having failed to work out that the surface of the Earth curves around a sphere. Or, as the saying goes, you can focus on the details of some fascinating trees and miss interesting facts about the forest as a whole.

In southwest Utah, geologists had noticed some pretty cool “trees.” The area had been volcanically active between 21 and 31 million years ago, building up a host of steep, volcanic peaks. A number of huge blocks of rock from these peaks, up to 2.5 square kilometers in area and 200 meters thick, are obviously out of place—they've been interpreted by geologists as the result of many landslides around the volcanoes. In a recent paper in Geology, David Hacker, Robert Biek, and Peter Rowley show that rather than being the result of many individual landslides, these are actually all part of one jaw-droppingly large event.

The deposit, called the Markagunt gravity slide, covers an area about 90 kilometers long and 40 kilometers wide and is hundreds of meters thick. During the event, all of this slid 30 kilometers or more. The scale puts run-of-the-mill landslides—as terrifying and deadly as they can be—to shame.

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