Plate tectonics is the process that underpins much of our understanding of the Earth. It explains many aspects of the Earth, from magnetic patterns in oceanic rocks to the distribution of plants and animals. How unusual is it? Well, it doesn’t seen to be happening on other rocky planets in our solar system. Many geologists have argued that plate tectonics wasn’t active during the earth’s early history. As astronomers find many rocky planets in other solar systems, the question of understanding how ‘typical’ plate tectonics has implications beyond the earth. How long has it been going on – how old is it?

{ Metageologist | Continue reading }

When analyzing cremated remains it is important to be aware of the broader burial and not focus so narrowly on the remains themselves if one wants to be able to understand the funeral process. We can learn a lot about the funeral from the bones themselves when they have been burned. The coloring on the remains, the amount of warping and the completeness can reveal fire temperature, how the body was placed on the pyre, whether it was clothed or was burned as dried bone, and if there were any problems with the burning (such as interruption by weather or incomplete incineration). However, often when cremation remains are collected there are macrobotanical or charcoal fragments which can further aid in interpretation by revealing details of the actual pyre construction.

Moskal-del Hoyo (2012) discusses the charcoal remains from Polish cremation necropoli in a new article from the Journal of Archaeological Sciences. She posits that analysis of the wood remains from pyre construction could be revealing about the identities of the individuals and the various necropoli.

{ Bones don’t lie | Continue reading }

{ Three satellites found that 97 percent of Greenland — the land mass second only to Antarctica for its volume of ice — underwent a thaw never before seen in 33 years of satellite tracking, NASA reported Tuesday. Satellite experts at first didn’t trust their readings, especially since they showed an incredible acceleration. Over four days, Greenland’s ice sheet — which covers 683,000 square miles – went from 40 percent in thaw to nearly entirely in thaw. | NBC | Continue reading | Thanks Samantha }

Manufacturers all have their own recipes for creating their fireworks; but the basic chemistry behind is the same for any fireworks.

Manufacturers start by combining a mixture of metals and oxidizers such as chlorates, perchlorates, or nitrates. The type of metals used influences the fireworks colours while the oxidizers provide the oxygen needed to achieve the required temperature for the reaction. Water is also added to the mixture to bind the metals and oxidizers together. This damp mixture is then cut into smaller pieces known as “stars”.

The manufacturers then fill a fireworks shell with “stars” and black powder, a mixture of potassium nitrate, charcoal, and sulfur. A time-delay fuse is also inserted into the shell which ignites the black powder and stars causing the shell to burst open.

There are 5 basic colours for fireworks, and each colour is produced by a different metal:

Red—strontium
Green—barium
Yellow—sodium
Blue—copper
White—aluminum, magnesium, or titanium

[…]

“Some colours are pretty easy, and those colours would be red and green,” says Worsey, “but you can tell how good a firework manufacturer is by the quality of their blues.” Blue is such a difficult colour to produce because the reaction temperature has to be perfect.

[…]

Some fireworks create familiar shapes like as rings, stars, and hearts as they explode. The trick behind these fireworks is the plastic mold that’s placed inside the fireworks shell.

{ Basal Science Clarified | Continue reading }

artwork { Cy Twonbly, Untitled, 1993 }

The other influence happened when I was nine or ten. I went back East to visit relatives in New York and one of my uncles took me to a Russian Jewish bathhouse. It was exotic and interesting and although I don’t remember it from a sensual level, it was an unusual experience. I realized that bathing was an activity that people could indulge in. I remember, too, that there was food afterwards — it was great! Later, when I was in architecture school at UCLA, I visited a place that had a nice bath, and I began to take baths in the afternoon. I liked to take a bath after lunch. I know it is an odd time for it, but if you’re self-employed and are kind of a dreamer, it works. Then in Japan I started to take a bath before dinner, at six or seven o’clock. […]

Bathrooms are everywhere. Just about everyone has one. And every bathroom, no matter how crude or sophisticated, comes equipped with all the elements of primal poetry:

Water and/or steam.
Hot, cold, and in between.
Nakedness.
Quietness.
Illumination.

[…]

The WET distribution system started really small — hand delivery to a few select shops — and grew significantly through the life of the magazine.

{ Leonard Koren/LA Review of Books | Continue reading }

Human use of water contributes markedly to rising tides.

During the latter half of the twentieth century, global sea level rose by about 1.8 millimetres per year, according to data from tide gauges.

The combined contribution from heating of the oceans, which makes the water expand, along with melting of ice caps and glaciers, is estimated to be 1.1 millimetres per year, which leaves some 0.7 millimetres per year unaccounted for. This gap has been considered an important missing piece of the puzzle in estimates for past and current sea-level changes and for projections of future rises.

It now seems that the effects of human water use on land could fill that gap.

A team of researchers reports in Nature Geoscience that land-based water storage could account for 0.77 millimetres per year, or 42%, of the observed sea-level rise between 1961 and 2003. Of that amount, the extraction of groundwater for irrigation and home and industrial use, with subsequent run-off to rivers and eventually to the oceans, represents the bulk of the contribution.

{ Nature | Continue reading }

photo { Joel Barhamand }

New findings at the Wonderwerk Cave, in South Africa, suggest that early humans started using fire 1 million years ago, approximately 300,000 years earlier than previously thought.

{ United Academics | Continue reading }

{ Only 500 people have been to space, only three people have been to the bottom of the ocean, but no one has ever attempted to journey to the core of an active volcano. Until now. Using patented carbon-carbon materials pioneered for deep space exploration, Virgin is proud to announce a revolutionary new vehicle, VVS1, which will be capable of plunging three people into the molten lava core of an active volcano. | Virgin | Continue reading | Thanks Tim }

Spontaneous Human Combustion occurs when a human body bursts into flame and is reduced to ashes without any apparent external source of ignition. Moreover, while the body is almost completely incinerated, which requires temperatures of about 3,000 degrees, the rest of the room, the furniture remain almost undamaged by the fire. SHC takes place in Charles Dickens’ novels but also in contemporary police investigations. A few months ago, the badly burned body of a pensioner was found in his living room in Galway, Ireland. Apart from his body, investigators could only find minor damage on the ceiling above him and the floor beneath him. “This fire was thoroughly investigated and I’m left with the conclusion that this fits into the category of spontaneous human combustion, for which there is no adequate explanation,” said the coroner.

{ We Make Money Not Art | Continue reading | Thanks Rob }

photo { Mark Thiessen }

Hoekstra and Hung (2002) were the first to introduce the concept of the “water footprint” of a nation, which is the total volume of freshwater used to produce the goods and services consumed by the nation’s population.

Therefore, in order to calculate Dutch coffee and tea related water consumption accurately, one must not only include the amount of water used in coffee machines or kettles but also the “virtual water content”, which is the volume of water needed to produce said coffee or tea. (…)

So just how much water goes into the production of a single cup of coffee in the Netherlands? 

Well, the Dutch water footprint was much bigger for coffee than it was for tea because the Dutch consume a lot more coffee than tea and tea has a lower virtual water content than coffee (10.4 cubic metres per kg of tea vs. 20.4 cubic metres per kg of coffee).

If you take into account the 7 grams of roasted coffee that goes on average into making a single cup and that a standard cup of coffee is about 125 ml, you find out that a total of 140 Liters of water goes into making a single cup of coffee in a Dutch household.

Now, the Dutch drink an average 3 cups of coffee a day, which totals to 2.6 billion cubic meters of water being used every year to satisfy the population’s need for caffeine.

{ Salamander Hours | Continue reading }

photo { Loretta Lux }

Dmitri Mendeleev (1834 – 1907) was a Russian chemist and inventor. He is credited as being the creator of the first version of the periodic table of elements. Using the table, he predicted the properties of elements yet to be discovered.

{ Wikipedia | Continue reading }

photos { 1. Daniel Everett | 2. Lars Tunbjörk, Stockbroker Tokyo, 1999 }

The sun strikes every square meter of our planet with more than 1,360 watts of power. Half of that energy is absorbed by the atmosphere or reflected back into space. 700 watts of power, on average, reaches Earth’s surface. Summed across the half of the Earth that the sun is shining on, that is 89 petawatts of power. By comparison, all of human civilization uses around 15 terrawatts of power, or one six-thousandth as much. In 14 and a half seconds, the sun provides as much energy to Earth as humanity uses in a day. (…)

It’s small wonder, then, that scientists and entrepreneurs alike are investing in solar energy technologies to capture some of the abundant power around us. Yet solar power is still a miniscule fraction of all power generation capacity on the planet. There is at most 30 gigawatts of solar generating capacity deployed today, or about 0.2 percent of all energy production. (…)

Over the last 30 years, researchers have watched as the price of capturing solar energy has dropped exponentially. There’s now frequent talk of a “Moore’s law” in solar energy. (…)

The cost of solar, in the average location in the U.S., will cross the current average retail electricity price of 12 cents per kilowatt hour in around 2020, or 9 years from now. (…) 10 years later, in 2030, solar electricity is likely to cost half what coal electricity does today.

{ Scientific American | Continue reading | via/more: Overcoming Bias }

photo { Eylül Aslan }

Emotional tears may be uniquely human and are an effective signal of distress in adults. The present study explored whether tears signal distress in younger criers and whether the effect of tears on observers is similar in magnitude across the life span. Participants rated photographs of crying infants, young children, and adults, with tears digitally removed or added. The effectiveness of tears in conveying sadness and eliciting sympathy was greatest for images of adults, intermediate for images of children, and least potent for images of infants. These findings suggest that the signal value of tears varies with the age of the crier. The results may shed light on the functional significance of crying at different stages of human development.

{ Evolutionary Psychology | Continue reading | PDF }

A Waboba is a ball that bounces on water (wa-ter bo-uncing ba-ll). That makes it kind of unusual since a simple experiment will show that many balls do not bounce on water. And that raises an interesting question–how does the Waboba work?

Today we get an answer from Michael Wright at Brigham Young University in Utah and a few buddies. These guys videoed the way three balls interact with water when bounced.

A Superball, which is solid and so has a relatively small surface area for its mass, burrows deep into the water, even when it hits at a shallow angle. So it does not bounce.

A raquet ball, on the other hand,is hollow and so has a larger surface area ratio to mass ratio. When thrown at a shallow angle, it penetrates only a small distance into the water creating a depression in the surface through which it planes back onto the surface. So it rebounds a little.

The Waboba is hollow but it is also soft. (…) Because it is soft, the ball flattens into disc-shape when it hits the surface and this allows it to aquaplane efficiently across the surface. (…)

Why might this be useful? Wright and co don’t say in their video but the fact that one of the team is with the Naval Undersea Warfare Center in Newport might offer a clue.

{ The Physics arXiv Blog | Continue reading }

artwork { Ellsworth Kelly, Yellow White, 1961 }

Anyone who has ever been out in the rain too long or soaked for hours in a tub knows the prunelike effect it can have on your hands and feet. Conventional wisdom suggests it is nothing more than the skin absorbing water.

But a number of questions have puzzled scientists. Why do “wet wrinkles” appear only on the hands and feet? And why are the most prominent wrinkles at the ends of the digits? Surgeons already know that cutting nerves in a finger prevents the wrinkling, suggesting the process is controlled by the nervous system.

Now a paper in the journal Brain, Behavior and Evolution offers more evidence that wet wrinkles serve a purpose: better grip and traction.

{ NY Times | Continue reading }

gouache and pencil on paper { Dick Blair }

Peter Brabeck-Letmathe chairs Nestlé, the world’s 44th-largest company, which last year earned US$10.5 billion in profits on US$121.1 billion in revenues. He is the consummate international businessman, bargaining hard, overseeing 280,000 employees, outflanking competitors and at ease with heads of state. Yet Brabeck remains incapable of negotiating one simple and irreplaceable ingredient without which his company ceases to exist: water.

He hardly seems a gloomy Malthusian, yet Brabeck foresees “limits to growth” because our global fresh water supply is both finite and being rapidly, stupidly, depleted. The world can sustainably use 4,200 cubic kilometres of water, he notes, but it consumes 4,500 even as aquifers plummet and rivers run dry.

{ China Dialogue | Continue reading }

Some unusual solar readings, including fading sunspots and weakening magnetic activity near the poles, could be indications that our sun is preparing to be less active in the coming years.

The results of three separate studies seem to show that even as the current sunspot cycle swells toward the solar maximum, the sun could be heading into a more-dormant period, with activity during the next 11-year sunspot cycle greatly reduced or even eliminated.

{ Space | Continue reading | + video | Read more: Major Drop in Solar Activity Predicted }

artwork { Richard Serra, out-of-round X, 1999 | On view through Aug. 28, 2011, at The Metropolitan Museum of Art, NYC }

{ I’ve just come across a deeply disturbing paper: Attempted ignition of petrol vapour by lit cigarettes and lit cannabis resin joints. The authors set out to discover whether you could set petrol on fire by dropping a lit cigarette or hash joint onto it. It turns out, surprisingly, that you can’t. | Neuroskeptic | full story }

The magnitude-8.9 quake that struck off Japan’s coast on March 11 is the largest in the country’s recorded history.

Map of the Damage From the Japanese Earthquake.

Japan’s Strict Building Codes Saved Lives. From seawalls that line stretches of Japan’s coastline, to skyscrapers that sway to absorb earthquakes, to building codes that are among the world’s most rigorous, no country may be better prepared to withstand earthquakes than Japan. More: Some Perspective On The Japan Earthquake.

When Tsunami Warning System Works, And When It Doesn’t

Japan Earthquake Demonstrates the Limits—and Power—of Science.

photo { Replica of seismograph invented by Zhang Heng in China in the 2nd century A.D. }

People with full bladders make better decisions.

Researchers discovered the brain’s self-control mechanism provides restraint in all areas at once. They found people with a full bladder were able to better control and “hold off” making important, or expensive, decisions, leading to better judgement. (…)

Dr Mirjam Tuk, who led the study, said that the brain’s “control signals” were not task specific but result in an “unintentional increase” in control over other tasks.

“People are more able to control their impulses for short term pleasures and choose more often an option which is more beneficial in the long run,” she said. (…)

They concluded that people with full bladders were better at holding out for the larger rewards later.

{ Telegraph | Continue reading | Thanks Tim! }