Thursday, February 12, 2015

How Little We Know

A couple of stories came by my internetting today, one from NASA regarding the sun, one about the deepest borehole in the world, and one about the oceans' role in ending the Ice Age.


We all know the Sun is a big burning ball of gas, but the text in this article reveals something to me (remember, by the way, the principle of Confirmation Bias: I don't believe humans cause global climate change, so these things jump out at me): we don't understand the sun very well.
“The images that have all the pretty loops and arches are extremely hot material,” physicist Dean Pesnell said in an interview with Yahoo News. “We would like to understand where all those arches come from. They are filled with things that are about 2 million degrees. The sun itself is just about 10,000 degrees Fahrenheit.”
The borehole article is filled with things we didn't know, and it's from Mother Nature Network, no doubt a bastion of "humans are killing the planet" thinking (caveat: I haven't checked that claim).

Before the hole was drilled, geologists could only hypothesize about the composition of the Earth's crust. Needless to say, the amount of geological data produced by the project was unprecedented. Mostly, it revealed just how little we really know about our planet.
For instance, one of the most surprising findings was the absence of the transition from granite to basalt at a depth between 3 and 6 kilometers below the surface. Previously, scientists had used seismic waves to glean information about the composition of the crust. They had discovered that a discontinuity existed at this depth, which they assumed was due to a transition in rock type. But the borehole drillers found no such transition; instead they found only more granite. It turns out that the discontinuity revealed by the seismic waves was actually due to a metamorphic change in the rock, rather than a change in rock type. It was a humbling realization for theorists, to say the least.
Even more surprising, the rock had been thoroughly fractured and was saturated with water. Free water was not supposed to exist at such depths. Geologists now surmise that the water consists of hydrogen and oxygen atoms that were squeezed out of the surrounding rock by enormous pressure, and is retained there due to a layer of impermeable rock above.
Researchers also described the mud that flowed out of the hole as "boiling" with hydrogen. The discovery of such large quantities of hydrogen gas was highly unexpected.
By far the most riveting discovery from the project, however, was the detection of microscopic plankton fossils in rocks over 2 billion years old, found four miles beneath the surface. These "microfossils" represented about 24 ancient species, and were encased in organic compounds which somehow survived the extreme pressures and temperatures that exist so far beneath the Earth.
The final mystery revealed by the borehole was the reason drilling operations had to be abandoned. Once the drill reached depths in excess of about 10,000 feet, the temperature gradient suddenly began to increase unexpectedly. At the hole's maximum depth, temperatures skyrocketed to 356 degrees Fahrenheit, which was much higher than the 212 degrees Fahrenheit originally predicted. The drill was rendered useless at such temperatures.
The project was officially closed down in 2005, and the site has since fallen into disrepair. The hole itself was welded shut by the rusted metal cap that today covers it, as if to permanently hide the hole's many mysteries from the surface world. 
 Though the hole's depth is impressive, it's a small fraction of the distance to the center of the Earth, which is estimated to be nearly 4,000 miles deep. By comparison, the Voyager 1 spacecraft, which has reached the outer layers of our solar system, has relayed information from over 10 billion miles away. The human race truly understands less about the ground beneath its very feet than it does about the cosmos that abound. It's humbling to realize just how much mystery still exists right here on our little blue world.


Lastly, let's peruse the article about the oceans.

"The oceans are leaking carbon dioxide to the atmosphere," said study co-author Gavin Foster from the University of Southampton in the United Kingdom.
The findings suggest these regions were pumping carbon dioxide to the atmosphere. The gas concentrations in the two regions spiked at different times, hinting that different processes underlie the rise in ocean carbon, the researchers said. However, in both cases the scientists think carbon dioxide levels in these two regions jumped because water rich in carbon and nutrients welled up from the deep ocean. 
Yet scientists still puzzle over what triggered these giant burps in greenhouse gas. Leading theories include changes in ocean currents or wind patterns. Some researchers recently suggested that sea-level drops triggered underwater volcanoes to erupt more vigorously, belching carbon dioxide in the process.
"We don't know the ultimate case," Foster said. "[But] we're one step toward the answer."
The researchers plan to test additional sites and examine how carbon dioxide levels changed through the glacial cycle, he said.


Not man, certainly 10,000 years ago. They. Don't. Know. There is also no Cause/Effect relationship proven between CO2 and temperature ("proven" being the important word there, by the way)


Seriously, readers, don't get fussed and have your tubes tied or something. We don't know everything we think we know.


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