The time has come. The time is here at last. Now is the time to gather around and take a well deserved hiatus from the politics of the day. Science talk is here. New discoveries, new takes on old knowledge, and other bits of news are all available for the perusing in today's information world. Over the fold are selections from the past week from a few of the many excellent science news sites around the world. Today's tidbits include soil "liquefaction" key to much of damage around Japan reactor, Jupiter like worlds push shock waves ahead of them to protect their atmosphere, sugarcane cools the climate after deforestation, using leaves characteristics improves accuracy measuring past climates, fossil sirenians give scientists a new look at ancient climate, and the current high price of gold is driving Amazon deforestation. Gather yourselves around. Pull up that comfy chair and bask in the sunshine. There is plenty of room for everyone. Get ready for one more session of Dr. Possum's science education and entertainment.
Featured Stories
Researchers were surprised to find the extent the area of soil 'liquefaction' secondary to the recent Japan earthquake.
The massive subduction zone earthquakes capable of this type of shaking, which are the most powerful in the world, don’t happen everywhere, even in other regions such as Southern California that face seismic risks. But an event almost exactly like that is expected in the Pacific Northwest from the Cascadia Subduction Zone, and the new findings make it clear that liquefaction will be a critical issue there.
Many parts of that region, from northern California to British Columbia, have younger soils vulnerable to liquefaction - on the coast, near river deposits or in areas with filled ground. The “young” sediments, in geologic terms, may be those deposited within the past 10,000 years or more. In Oregon, for instance, that describes much of downtown Portland, the Portland International Airport, nearby industrial facilities and other cities and parts of the Willamette Valley.
Anything near a river and old flood plains is a suspect, and the Oregon Department of Transportation has already concluded that 1,100 bridges in the state are at risk from an earthquake on the Cascadia Subduction Zone. Fewer than 15 percent of them have been retrofitted to prevent collapse.
Jupiter like planets circling other stars push shock waves ahead of them to protect their atmosphere. The phenomenon is much like the 'bow-wave' effect of earth which protects against the solar wind.
Hot Jupiters are similar to the planet Jupiter in our own Solar System but located far closer to their host star (WASP-12b is 3.4 million km away from WASP-12 which compares with the Earth-Sun distance of 150 million km). With such a small distance between them violent interactions between the star and the planet can take place.
As one of the largest hot Jupiters discovered to date, WASP-12b also gives a unique opportunity to observe the interactions between the planetary magnetic field and the host star’s magnetic field. The very presence of a magnetic field reveals that the planet must have a conducting, rotating interior.
There is now tantalizing new evidence from Hubble Space Telescope data that a magnetosphere exists around WASP-12b. Observations of the planet taken in ultraviolet wavelengths by a team including scientists from the Open University reveal that the start of the dip in the light from the star during the transit of the planet is earlier in ultraviolet than visible light. Originally, this was thought to be caused by material flowing from the planet onto the star. The St Andrews group have however determined that the planet ploughs into a supersonic headwind and pushes a shock ahead it – just like the one around a supersonic jet aircraft.
Areas of forest are being cleared for agriculture and for the growing of biofuel sources such as sugarcane.
As (researcher) Loarie explained: “We found that shifting from natural vegetation to crops or pasture results in local warming because the plants give off less beneficial water. But the bamboo-like sugarcane is more reflective and gives off more water—much like the natural vegetation. It’s a potential win-win for the climate—using sugarcane to power vehicles reduces carbon emissions, while growing it lowers the local air temperature.”
The scientists found that converting from natural vegetation to crop/pasture on average warmed the cerrado by 2.79 °F (1.55 °C), but that subsequent conversion to sugarcane, on average, cooled the surrounding air by 1.67 °F (0.93°C).
The researchers emphasize that the beneficial effects are contingent on the fact sugarcane is grown on areas previously occupied by crops or pastureland, and not in areas converted from natural vegetation. It is also important that other crops and pastureland do not move to natural vegetation areas, which would contribute to deforestation.
The study of climate change through the centuries is an ongoing and evolving process.
The results showed:
• Leaves in cold climates typically have larger, more numerous teeth, and are more dissected. Leaves in wet climates are larger and have fewer, smaller teeth.
• Leaf habit (deciduous vs. evergreen), local water availability and phylogenetic history all affect the relationships between climate and leaf size and shape.
• The researchers' multivariate mean annual temperature and mean annual precipitation models offer strong improvements in accuracy and precision over single variable approaches. For example, the mean annual temperature estimates for most of North American fossil floras were considerably warmer and wetter and in better agreement with independent paleoclimate evidence. This suggests that these new models offer the potential to provide climate estimates that will help scientists better understand ancient climates.
Fossil sirenians (sea-cows, a relative of today's manatees) are giving scientists a new look at the ancient waters in which they swam.
A new look at climate during the Eocene, when Earth underwent a dramatic change, could help scientists better understand global climate change today.
Most scientists assumed that the oxygen isotopic composition of seawater in the past was very similar to that of today, with high values at low latitudes and low values at high latitudes.
Isotopes are variants of atoms of a particular chemical element, in this case oxygen, with differing numbers of neutrons.
"But when we looked at the oxygen isotopic values of the fossils from low-latitude sites for the Eocene, they were much lower than we would predict," says (researcher) Clementz.
The finding suggests that low-latitude sites during the Eocene were much wetter than today.
Gold has been mined in the Amazon River basin for centuries.
Deforestation in parts of the Peruvian Amazon has increased six-fold in recent years as small-scale miners, driven by record gold prices, blast and clear more of the lowland rainforest.
(snip)
Roughly 7,000 hectares, or about 15,200 acres, of pristine forest and wetlands were cleared at two large mining sites between 2003 and 2009, with a dramatic increase in deforestation occurring in the last three years.
Other Worthy Stories of the Week
Nature to get legal rights in Bolivia
Large galaxies stopped growing seven billion years ago
Kepler's census of sun-like stars
Could black trees blossom in a world with two suns?
Infection in the jaw of an ancient fossil
Flame retardants detected in peregrine falcon eggs
Bone munching worms from the deep sea survive on fish bones
Changes in land use favor the expansion of wild ungulates in Mediterranean climes
Green environments essential for human health
Scorpions, spiders, and sharks: Electron microscope images
Biggest spider fossil uncovered by scientists
Scientists see solar outburst in exquisite detail
Mercury on the rise in endangered Pacific sea birds
Melting ice on Arctic islands a major player in sea level rise
Australopithecus sediba could be direct ancestor of Homo
Composite material strong as steel and thin as paper
CERN atom smasher sets new record
Brown recluse spider range could expand with North American climate change
Contemporary climate change drives the extinction of American pikas
Lawn of native grasses beats traditional lawn for lushness and weed resistance
For even more science news:
General Science Collectors:
Alpha-Galileo
BBC News Science and Environment
Eureka Science News
LiveScience
New Scientist
PhysOrg.com
SciDev.net
Science/AAAS
Science Alert
Science Centric
Science Daily
Scientific American
Space Daily
Blogs:
A Few Things Ill Considered Techie and Science News
Cantauri Dreams space exploration
Coctail Party Physics Physics with a twist.
Deep Sea News marine biology
Laelaps more vertebrate paleontology
List of Geoscience Blogs
ScienceBlogs
Space Review
Techonology Review
Tetrapod Zoologyvertebrate paleontology
Science Insider
Scientific Blogging.
Space.com
Wired News
Science RSS Feed: Medworm
The Skeptics Guide to the Universe--a combination of hard science and debunking crap
At Daily Kos:
This Week in Science by DarkSyde
Overnight News Digest:Science Saturday by Neon Vincent. OND tech Thursday by rfall.
Pique the Geek by Translator Sunday evenings about 9 Eastern time
All diaries with the DK GreenRoots Tag.
All diaries with the eKos Tag
A More Ancient World by matching mole
Astro Kos
SciTech at Dkos.
NASA picture of the day. For more see the NASA image gallery or the Astronomy Picture of the Day Archive.
Nile River Delta at night, NASA, Public Domain