geophysical science


One of the factors that complicates geophysical flows is that both the atmosphere and the ocean are stratified fluids with many stacked layers of differing densities. These variations in density can generate instabilities, trap rising or sinking fluids, and transmit waves. The animations above show flow over two ridges with dye visualization (top), velocity (middle), and contours of density (bottom). The upstream influence of the left ridge creates a smooth, focused flow that quickly becomes turbulent after the crest. The jet rebounds as a turbulent hydraulic jump before slowing again upstream of the second ridge. Like the first ridge, the second ridge also generates a hydraulic jump on the lee side. Clearly both stratification and the local topography play a big role in how air moves over and between the ridges. If prevailing winds favor these kinds of flows, it can help generate local microclimates. (Image credit and submission: K. Winters, source videos)


Engineer school: Done ✔
End of research masted: D-7 ⏳👍

Can’t wait to be done with all of this ! Studying for my oral exam on geophysical fluids dynamics 🌊 and trying to remember all these lessons I had months ago 😮💪

The health of our global citizenry is not a partisan subject. Frankly, it doesn’t matter what Repubs or Dems want, or even what you or I ‘think’ we want; rather, it’s about what we need, based on empirical, evidence-based decision making by which the data reveal to be the most accurate path to sustainability.

Led by the men and women on the forefront of medical research across an array of fields: biology, meteorology, genetics, genomics, artificial intelligence, machine learning, physiology, neuroscience, psychology, climatology, oceanography, ecology, biodiversity, agriculture, planetary science, geophysics, anthropology, paleontology, economics…the list of related concentrations pertaining to the health and survival of life necessary amongst the diverse family thriving in this biosphere are contributing to the information needed to address tomorrow.

Yet, Carl Sagan’s words still, hauntingly, ring true for our society in its present condition:

“We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.”

He followed by rhetorically postulating, “Who is making the decisions about science and technology in a democracy where no one understands anything about science and technology?”

Make no mistake – understanding how the world works at the fundamental level is not only liberating and exciting, it’s crucial in order to safeguard one’s intellect from being able to determine fact from fiction. And when arguments from authority are presented or asserted in a reactionary way, a continuously refined skepticism and knowledge of science (pertaining to and incorporating a global view of our society) will prevent us from being lied to so that we may hold said authority accountable. With persistence, we will appoint authority figures to positions of influence whom are scientifically literate themselves; that is, if artificial intelligence doesn’t step in and fill these roles for us to correct for human error.

To this end, I find it disturbing that the health and sustainability of our society has become so politicized and polarized to ad nauseam, moving beyond simple hypocrisy. Complaining about our imperfect healthcare system while pushing for environmental deregulation and, simultaneously, a resurgence of fossil fuels, is not hypocritical; it’s ignorance. Madness. And it’s betraying the very biosphere which enabled our existence, and enables it still.

—  @sagansense

This video is a high powered computer’s simulation of the New Zealand Earthquake earlier this month. The video shows the initiation of the earthquake rupture and then tracks the motion of the planet up and down and side to side as the waves from the earthquake spread out from the rupture. The video is played at roughly 2x the speed the waves actually propagated outwards.

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‘Curiosity’ exposes low CO2 level in Mars’ primitive atmosphere

The analysis of samples in situ in which CSIC participated shows that it did not contain the minimum CO2 level required for the existence of a liquid water lake in Gale Crater

The CO2 level in Mars’ primitive atmosphere 3.5 billion years ago was too low for sediments, such as those found by NASA’s Curiosity exploration vehicle in areas like the Gale Crater on the planet’s equator, to be deposited. This and other conclusions are drawn from a paper written with the participation of researchers from the Spanish National Research Council (CSIC) and published in the latest issue of the journal, Proceedings of the National Academy of Sciences (PNAS).

The area Curiosity has been analysing since 2012, as part of NASA’s Mars Science Laboratory mission, is composed primarily of sedimentary sequences deposited at the bottom of a lake 3.5 billion years ago. These sediments contain various secondary minerals, such as clays or sulphates, which indicate that the primitive surface was in contact with liquid water.

The existence of liquid water requires a warm surface temperature brought about by a minimum content of CO2 in the atmosphere. Yet this was not the case with Mars in its beginnings. “This contradiction has two possible solutions. Either we have not yet developed climatic models which explain the environmental conditions on Mars at the beginning of its history, or the Gale sedimentary sequences really did form in a very cold climate”, explains CSIC researcher Alberto Fairén, who works at the Centre for Astrobiology near Madrid (a joint centre run by CSIC and Spain’s National Institute of Aerospace Technology).

A very cold environment
“However, the rover has not found carbonates, thereby confirming the results of studies by all previous probes: carbonates are very scarce on the surface of Mars and, therefore, the CO2 level in the atmosphere was very low”, adds. Fairén.

Specifically, the direct analysis of samples on the surface of Mars carried out by these researchers shows that the level of CO2 in the atmosphere at the time the Gale Crater sediments were deposited was between 10 and 100 times less than the minimum required for the surface temperature to be above the freezing point of the liquid water.

On Earth, carbonate deposits form on lake and sea beds when CO2 in the atmosphere interacts with liquid water. Carbon dioxide is a gas capable of generating a powerful 'greenhouse effect’ and, therefore, of heating the planet.

According to the scientists, an image that maybe would describe Gale in the early days of Mars would be that of a glacial lake, surrounded by huge masses of ice, which would be partially or seasonally frozen. “The environment would have been similar to the Canadian Arctic or to Greenland today,” says the CSIC researcher.

In addition, although ice would have dominated, it would also have been common to find liquid water present in abundance. The formation of clays and sulphates would have occurred at specific places and times, seasonally, or under an ice cap in liquid water lakes.


Turbidity currents are a gravity-driven, sediment-laden flow, like a landslide or avalanche that occurs underwater. They are extremely turbulent flows with a well-defined leading edge, called a head. Turbidity currents are often triggered by earthquakes, which shake loose sediments previously deposited in underwater mountains and canyons. Once suspended, these sediments make the fluid denser than surrounding water, causing the turbidity current to flow downhill until its energy is expended and its sediment settles to form a turbidite deposit. By sampling cores from the seafloor, scientists studying turbidites can determine when and where magnitude 8+ earthquakes have occurred over the past 12,000+ years!  (Video credit: A. Teijen et al.; submitted by Simon H.)

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On the Rocks

This Heart is a Stone - Chapter 27

It hasn’t been an easy 15 years since since the barrier atop Mt. Ebott broke and monsters were reintroduced to the surface world. The uneasy acceptance of monsterkind was hard won by many sacrifices though over the years tensions have settled into a general, though in some cases begrudging, acceptance.

You are a grad student at the local university, eagerly pursuing a degree in Geophysics and Planetary Sciences in hopes of returning to the National Park Service. One step closer to the future you’ve had planned out since you were 17.

Plans change, though… and along the way, you might undergo a metamorphosis too.
*Please do not assume this is just a student/teacher kink fic, because it is not :)

Major volcanic eruptions can be accompanied by pyroclastic flows, a mixture of rock and hot gases capable of burying entire cities, as happened in Pompeii when Mt. Vesuvius erupted in 79 C.E. For even larger eruptions, such as the one at Peach Spring Caldera some 18.8 million years ago, the pyroclastic flow can be powerful enough to move half-meter-sized blocks of rock more than 150 km from the epicenter. Through observations of these deposits, experiments like the one above, and modeling, researchers were able to deduce that the Peach Spring pyroclastic flow must have been quite dense and flowed at speeds between 5 - 20 m/s for 2.5 - 10 hours! Dense, relatively slow-moving pyroclastic flows can pick up large rocks (simulated in the experiment with large metal beads) both through shear and because their speed generates low pressure that lifts the rocks so that they get swept along by the current. (Image credit: O. Roche et al., source)

Stone Cold

This Heart is a Stone - Chapter 28

It hasn’t been an easy 15 years since since the barrier atop Mt. Ebott broke and monsters were reintroduced to the surface world. The uneasy acceptance of monsterkind was hard won by many sacrifices though over the years tensions have settled into a general, though in some cases begrudging, acceptance.

You are a grad student at the local university, eagerly pursuing a degree in Geophysics and Planetary Sciences in hopes of returning to the National Park Service. One step closer to the future you’ve had planned out since you were 17.

Plans change, though… and along the way, you might undergo a metamorphosis too.
*Please do not assume this is just a student/teacher kink fic, because it is not :)

NASA Mission Reveals Speed of Solar Wind Stripping Martian Atmosphere

NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today.

MAVEN data have enabled researchers to determine the rate at which the Martian atmosphere currently is losing gas to space via stripping by the solar wind. The findings reveal that the erosion of Mars’ atmosphere increases significantly during solar storms. The scientific results from the mission appear in the Nov. 5 issues of the journals Science and Geophysical Research Letters.

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New light shed on end of Snowball Earth period

The second ice age during the Cryogenian period was not followed by the sudden and chaotic melting-back of the ice as previously thought, but ended with regular advances and retreats of the ice, according to research published by scientists from the University of Birmingham in the journal Nature Geoscience today (24 August 2015).

The researchers also found that the constant advance and retreat of ice during this period was caused by the Earth wobbling on its axis.

These ice ages are explained by a theory of Snowball Earth, which says that they represent the most extreme climatic conditions the world has ever known and yet they ended quite abruptly 635 million years ago. Little was known about how they ended – until now.

For the study, the scientists analyzed sedimentary rocks from Svalbard, Norway that were laid down in that ice age. The deposits preserved a chemical record which showed high levels of CO2 were present in the atmosphere. Carbon dioxide was low when the ice age started, and built up slowly over millions of years when the whole Earth was very cold – this period is represented only by frost-shattered rubble under the sediments.

Eventually the greenhouse warmth in the atmosphere from carbon dioxide caused enough melting for glaciers to erode, transport and deposit sediment. The sedimentary layers showed ice retreat and advance as well as cold arid conditions. They reveal a time when glacial advances alternated with even more arid, chilly periods and when the glaciers retreated, rivers flowed, lakes formed, and yet simple life survived.

As theory predicts, this icy Earth with a hot atmosphere rich in carbon dioxide had reached a ‘Goldilocks’ zone – too warm to stay completely frozen, too cold to lose its ice, but just right to record more subtle underlying causes of ancient climate change.

The geological researchers invited a French group of physicists who produce sophisticated climate models to test their theory that the advances and retreats of ice during this period were caused by the Earth wobbling on its axis in 20,000 year periods. The rocks and the models agreed: slight wobbles of the Earth on its spin axis caused differences in the heat received at different places on the Earth’s surface. These changes were small, but enough over thousands of years to cause a change in the places where snow accumulated or melted, leading the glaciers to advance and retreat. During this time the whole Earth would have looked like the Dry Valley regions of Antarctica – a very dry landscape, with lots of bare ground, but also containing glaciers up to 3 km thick.

Professor Ian Fairchild, lead investigator from the University of Birmingham’s School of Geography, Earth and Environmental Sciences, said: 'We now have a much richer story about what happened at the end of the Snowball Earth period. The sediment analysis has given us a unique window on what happened so many millions of years ago. We know that the Earth’s climate is controlled by its orbit, and we can now see the effect of that in this ancient ice age too.’

Inge Lehmann (1888-1993) was a Danish geophysicist and seismologist who, in 1936, discovered that the Earth has a solid inner core surrounded by a molten outer core. This overturned the previous belief that the Earth’s core was a single molten sphere.

She began her higher education by studying mathematics at the University of Copenhagen, and later at Cambridge. She made important investigations of the Earth’s structure, discovering, among other elements, a seismic discontinuity that was named after her. Today, the American Geophysical Society awards a medal in her honor.

What did Earth’s ancient magnetic field look like?

New work from Carnegie’s Peter Driscoll suggests Earth’s ancient magnetic field was significantly different than the present day field, originating from several poles rather than the familiar two. It is published in Geophysical Research Letters.
Earth generates a strong magnetic field extending from the core out into space that shields the atmosphere and deflects harmful high-energy particles from the Sun and the cosmos. Without it, our planet would be bombarded by cosmic radiation, and life on Earth’s surface might not exist. The motion of liquid iron in Earth’s outer core drives a phenomenon called the geodynamo, which creates Earth’s magnetic field. This motion is driven by the loss of heat from the core and the solidification of the inner core.
But the planet’s inner core was not always solid. What effect did the initial solidification of the inner core have on the magnetic field? Figuring out when it happened and how the field responded has created a particularly vexing and elusive problem for those trying to understand our planet’s geologic evolution, a problem that Driscoll set out to resolve.
Here’s the issue: Scientists are able to reconstruct the planet’s magnetic record through analysis of ancient rocks that still bear a signature of the magnetic polarity of the era in which they were formed. This record suggests that the field has been active and dipolar–having two poles–through much of our planet’s history. The geological record also doesn’t show much evidence for major changes in the intensity of the ancient magnetic field over the past 4 billion years. A critical exception is in the Neoproterozoic Era, 0.5 to 1 billion years ago, where gaps in the intensity record and anomalous directions exist. Could this exception be explained by a major event like the solidification of the planet’s inner core?
In order to address this question, Driscoll modeled the planet’s thermal history going back 4.5 billion years. His models indicate that the inner core should have begun to solidify around 650 million years ago. Using further 3-D dynamo simulations, which model the generation of magnetic field by turbulent fluid motions, Driscoll looked more carefully at the expected changes in the magnetic field over this period.
“What I found was a surprising amount of variability,” Driscoll said. “These new models do not support the assumption of a stable dipole field at all times, contrary to what we’d previously believed.”
His results showed that around 1 billion years ago, Earth could have transitioned from a modern-looking field, having a “strong” magnetic field with two opposite poles in the north and south of the planet, to having a “weak” magnetic field that fluctuated wildly in terms of intensity and direction and originated from several poles. Then, shortly after the predicted timing of the core solidification event, Driscoll’s dynamo simulations predict that Earth’s magnetic field transitioned back to a “strong,” two-pole one.
“These findings could offer an explanation for the bizarre fluctuations in magnetic field direction seen in the geologic record around 600 to 700 million years ago,” Driscoll added. “And there are widespread implications for such dramatic field changes.”
Overall, the findings have major implications for Earth’s thermal and magnetic history, particularly when it comes to how magnetic measurements are used to reconstruct continental motions and ancient climates. Driscoll’s modeling and simulations will have to be compared with future data gleaned from high quality magnetized rocks to assess the viability of the new hypothesis.

IMAGE….This is an illustration of ancient Earth’s magnetic field compared to the modern magnetic field courtesy of Peter Driscoll. Credit: Peter Driscoll


Earth’s Core Has An Inner Core Of Its Own

Geologists from the University of Illinois and Nanjing University in China applied earthquake resonance wave data to ‘look’ all the way through the Earth’s center. What they found was a nugget smaller than the moon.

By: Live Science Videos.