By Mejs Hasan
Clever Planets Website, Education & Outreach Coordinator
One of the main tasks of CLEVER Planets is to study how elements like carbon, hydrogen, oxygen, and others ended up on Earth. And not just ended up on Earth, but in places on Earth where they could be accessed by emerging life-forms that must have them (i.e., not buried deeply beneath the surface.)
Now, CLEVER Planets researchers have helped to write “Deep carbon: Past to present“, a book that “offers a critical summary” of what is known about deep carbon. “Deep” carbon refers to buried carbon. It may be buried, but scientists are discovering that deep carbon still has a large impact on oceans, the atmosphere, and life on the surface of the planet.
The new book delves into topics like: how much deep carbon is there? Where does it come from and how does it affect the global carbon cycle? These are questions that 1200 members of the global Deep Carbon Observatory have been wrestling with over the last 10 years.
The book will be available in hardback form in December, but you can read it on-line for free right now. It is 670 pages long in total.
The book was co-edited by Rajdeep Dasgupta, the head of CLEVER Planets research.
Dasgupta and his student Daman Grewal also wrote the second chapter in the book: “Origin and early differentiation of carbon and associated life-essential volatile elements on Earth.”
A quartet of CLEVER Planets co-investigators, post-docs, and collaborators also wrote chapter 11: “A framework for understanding whole Earth carbon cycling.”
This is an Open Access publication
– AUGUST 30, 2019
Thomas Jones’ “universal break-up criterion” won’t help with meltdowns of the heart, but it will help volcanologists study changing lava conditions in common volcanic eruptions.
Jones, of Rice University, studies the behavior of low-viscosity lava, the runny kind that’s found at most volcanoes. About two years ago, he began a series of lab experiments and field observations that provided the raw inputs for a new fluid dynamic model of lava break-up. The work is described in a paper in Nature Communications.
Low-viscosity lava is the red-hot, flowing type one might see at Hawaii’s famed Kilauea volcano, and Jones said it usually behaves in one of two ways.
“It can bubble or spew out, breaking into chunks that spatter about the vent, or it can flow smoothly, forming lava streams that can rapidly move downhill,” he said.
But that behavior can sometimes change quickly during the course of an eruption, and so can the associated dangers: While spattering eruptions throw hot lava fragments into the air, lava flows can threaten to destroy whole neighborhoods and towns.
Jones’ model, the first of its kind, allows scientists to calculate when an eruption will transition from a spattering spray to a flowing stream, based upon the liquid properties of the lava itself and the eruption conditions at the vent.
Jones said additional work is needed to refine the tool, and he looks forward to doing some of it himself.
“We will validate this by going to an active volcano, taking some high-speed videos and seeing when things break apart and under what conditions,” he said. “We also plan to look at the effect of adding bubbles and crystals, because real magmas aren’t as simple as the idealized liquid in our mathematical model. Real magmas can also have bubbles and crystals in them. I’m sure those will change things. We want to find out how.”
Jones said pairing the new model with real-time information about a lava’s liquid properties and eruption conditions could allow emergency officials to predict when an eruption will change style and become a hazard to at-risk communities.
“We want to use this as a forecasting tool for eruption behavior,” he said. “By developing a model of what’s happening in the subsurface we can then watch for indications that it’s about to cross the tipping point and change behavior.”
The study was co-authored by C.D. Reynolds of the University of Birmingham in the United Kingdom and S.C. Boothroyd of Durham University, also in the UK. The research was supported by the UK’s National Environment Research Council and Rice University.
Description from Sound Cloud:
With all the planets out there in the galaxy and Universe, it’s only a matter of time and data until we find another one with life on it. (Probably.) But while most of the searches have focused on finding the next Earth, sometimes called Earth 2.0, that’s very likely an overly restrictive way to look for life. Biosignatures, or more conservatively, bio-hints, might not only be plentiful on worlds very different from our own, but around Solar Systems other than our own. Earth-like worlds, in fact, might not even be the most ubiquitous places for life to arise in the Universe.
I’m happy to welcome scientist Adrian Lenardic onto the Starts With A Bang podcast, and explore what just might be out there if we look for life beyond our idea of Earth 2.0!
(Image credit: JPL-Caltech/NASA.)
You can read Ethan Siegel’s digest of the podcast on Forbes:
JUNE 12, 2019
Old ice and snow yields tracer of preindustrial ozone
Ancient air bubbles answer question about ozone levels after Industrial Revolution
HOUSTON — (June 12, 2019) — Using rare oxygen molecules trapped in air bubbles in old ice and snow, U.S. and French scientists have answered a long-standing question: How much have “bad” ozone levels increased since the start of the Industrial Revolution?
“We’ve been able to track how much ozone there was in the ancient atmosphere,” said Rice University geochemist Laurence Yeung, the lead author of a study published online today in Nature. “This hasn’t been done before, and it’s remarkable that we can do it at all.”
Researchers used the new data in combination with state-of-the-art atmospheric chemistry models to establish that ozone levels in the lower atmosphere, or troposphere, have increased by an upper limit of 40% since 1850.
“These results show that today’s best models simulate ancient tropospheric ozone levels well,” said Yeung. “That bolsters our confidence in their ability to predict how tropospheric ozone levels will change in the future.”
The Rice-led research team includes investigators from the University of Rochester in New York, the French National Center for Scientific Research’s (CNRS) Institute of Environmental Geosciences at Université Grenoble Alpes (UGA), CNRS’s Grenoble Images Speech Signal and Control Laboratory at UGA and the French Climate and Environmental Sciences Laboratory of both CNRS and the French Alternative Energies and Atomic Energy Commission (CEA) at the Université Versailles-St Quentin.
“These measurements constrain the amount of warming caused by anthropogenic ozone,” Yeung said. For example, he said the most recent report from the Intergovernmental Panel on Climate Change (IPCC) estimated that ozone in Earth’s lower atmosphere today is contributing 0.4 watts per square meter of radiative forcing to the planet’s climate, but the margin of error for that prediction was 50%, or 0.2 watts per square meter.
“That’s a really big error bar,” Yeung said. “Having better preindustrial ozone estimates can significantly reduce those uncertainties.
“It’s like guessing how heavy your suitcase is when there’s a fee for bags over 50 pounds,” he said. “With the old error bars, you’d be saying, ‘I think my bag is between 20 and 60 pounds.’ That’s not good enough if you can’t afford to pay the penalty.”
Ozone is a molecule that contains three oxygen atoms. Produced in chemical reactions involving sunlight, it is highly reactive, in part because of its tendency to give up one of its atoms to form a more stable oxygen molecule. The majority of Earth’s ozone is in the stratosphere, which is more than five miles above the planet’s surface. Stratospheric ozone is sometimes called “good” ozone because it blocks most of the sun’s ultraviolet radiation, and is thus essential for life on Earth.
The rest of Earth’s ozone lies in the troposphere, closer to the surface. Here, ozone’s reactivity can be harmful to plants, animals and people. That’s why tropospheric ozone is sometimes called “bad” ozone. For example, ozone is a primary component of urban smog, which forms near ground level in sunlit-driven reactions between oxygen and pollutants from motor vehicle exhaust. The Environmental Protection Agency considers exposure to ozone levels greater than 70 parts per billion for eight hours or longer to be unhealthy.
“The thing about ozone is that scientists have only been studying it in detail for a few decades,” said Yeung, an assistant professor of Earth, environmental and planetary sciences. “We didn’t know why ozone was so abundant in air pollution until the 1970s. That’s when we started to recognize how air pollution was changing atmospheric chemistry. Cars were driving up ground-level ozone.”
While the earliest measurements of tropospheric ozone date to the late 19th century, Yeung said those data conflict with the best estimates from today’s state-of-the-art atmospheric chemistry models.
“Most of those older data are from starch-paper tests where the paper changes colors after reacting with ozone,” he said. “The tests are not the most reliable — the color change depends on relative humidity, for example — but they suggest, nevertheless, that ground-level ozone could have increased up to 300% over the past century. In contrast, today’s best computer models suggest a more moderate increase of 25-50%. That’s a huge difference.
“There’s just no other data out there, so it’s hard to know which is right, or if both are right and those particular measurements are not a good benchmark for the whole troposphere,” Yeung said. “The community has struggled with this question for a long time. We wanted to find new data that could make headway on this unsolved problem.”
Finding new data, however, is not straightforward. “Ozone is too reactive, by itself, to be preserved in ice or snow,” he said. “So, we look for ozone’s wake, the traces it leaves behind in oxygen molecules.
“When the sun is shining, ozone and oxygen molecules are constantly being made and broken in the atmosphere by the same chemistry,” Yeung said. “Our work over the past several years has found a naturally occurring ‘tag’ for that chemistry: the number of rare isotopes that are clumped together.”
Yeung’s lab specializes in both measuring and explaining the occurrence of these clumped isotopes in the atmosphere. They are molecules that have the usual number of atoms — two for molecular oxygen — but they have rare isotopes of those atoms substituted in place of the common ones. For example, more than 99.5% of all oxygen atoms in nature have eight protons and eight neutrons, for a total atomic mass number of 16. Only two of every 1,000 oxygen atoms are the heavier isotope oxygen-18, which contains two additional neutrons. A pair of these oxygen-18 atoms is called an isotope clump.
The vast majority of oxygen molecules in any air sample will contain two oxygen-16s. A few rare exceptions will contain one of the rare oxygen-18 atoms, and rarer still will be the pairs of oxygen-18s.
Yeung’s lab is one of the few in the world that can measure exactly how many of these oxygen-18 pairs are in a given sample of air. He said these isotope clumps in molecular oxygen vary in abundance depending on where ozone and oxygen chemistry occurs. Because the lower stratosphere is very cold, the odds that an oxygen-18 pair will form from ozone/oxygen chemistry increase slightly and predictably compared to the same reaction in the troposphere. In the troposphere, where it is warmer, ozone/oxygen chemistry yields slightly fewer oxygen-18 pairs.
With the onset of industrialization and the burning of fossil fuels around 1850, humans began adding more ozone to the lower atmosphere. Yeung and colleagues reasoned that this increase in the proportion of tropospheric ozone should have left a recognizable trace — a decrease in the number of oxygen-18 pairs in the troposphere.
Using ice cores and firn (compressed snow that has not yet formed ice) from Antarctica and Greenland, the researchers constructed a record of oxygen-18 pairs in molecular oxygen from preindustrial times to the present. The evidence confirmed both the increase in tropospheric ozone and the magnitude of the increase that had been predicted by recent atmospheric models.
“We constrain the increase to less than 40%, and the most comprehensive chemical model predicts right around 30%,” Yeung said.
“One of the most exciting aspects was how well the ice-core record matched model predictions,” he said. “This was a case where we made a measurement, and independently, a model produced something that was in very close agreement with the experimental evidence. I think it shows how far atmospheric and climate scientists have come in being able to accurately predict how humans are changing Earth’s atmosphere — particularly its chemistry.”
Study co-authors include Asmita Banerjee and Huanting Hu, both of Rice; Lee Murray of the University of Rochester; Patricia Martinerie, Jérôme Chappellaz and Emmanuel Witrant, all of CNRS and Université Grenoble Alpes; and Anaïs Orsi from CEA at the Laboratoire des Sciences du Climat et de l’Environnement. This research was supported by the David and Lucile Packard Foundation, the European Research Council, CNRS and the French Polar Institute IPEV.
The DOI of the Nature paper is: 10.1038/s41586-019-1277-1
A copy of the paper is available at: http://dx.doi.org/10.1038/s41586-019-1277-1
Yeung lab: yeunglab.org
Rice Department of Earth, Environmental and Planetary Sciences: earthscience.rice.edu
Wiess School of Natural Sciences: naturalsciences.rice.edu
VIDEO is available at:
High-resolution IMAGES are available for download at:
CAPTION: Rice University researchers and collaborators used ice cores, like the one shown here from Antarctica, in combination with atmospheric chemistry models to establish an upper limit for the increase in ozone levels in the lower atmosphere since 1850. (Photo by Jeff Fitlow/Rice University)
CAPTION: Rice University geochemists Laurence Yeung and Asmita Banerjee studied the increase in tropospheric ozone from preindustrial time to present by constructing a record of oxygen-18 “clumped isotope” pairs from tiny bubbles of atmospheric gas that were trapped in ice and snow in Antarctica and Greenland. (Photo by Jeff Fitlow/Rice University)
Two Rice University faculty members have been selected as 2019 Alfred P. Sloan Research Fellows.
Mark Torres, assistant professor of Earth, environmental and planetary sciences, was honored for his work in the field of ocean sciences, and Ming Yi, assistant professor of physics and astronomy, was awarded for physics. The two-year, $70,000 fellowships seek to stimulate fundamental research by early-career scientists and scholars while recognizing their distinguished performance and unique potential to make substantial contributions to their fields.
Torres and Yi are among 126 U.S. and Canadian researchers to receive a 2019 fellowship.
“This fellowship gives me freedom to pursue interesting ideas and, in a sense, validates the work I’ve started to do at Rice,” Torres said. “At this point in my career, these are my first steps on my own, and it’s nice to know those steps are headed in the right direction.”
Torres’ high school was attached to a museum of paleontology, which sparked his passion for studying Earth. Encouraged to turn this passion into a career, he took geology classes and found work at the interface between geology and chemistry to be the most captivating. His research concerns how concentrations of carbon dioxide and oxygen in the atmosphere are regulated over geologic time and what makes planets habitable.
“The chemistry of the ocean is really important,” Torres said. “The amount of carbon dioxide in the atmosphere is very dependent on the chemistry of the ocean. Most of my research so far has focused on how rivers, by delivering different chemical elements to the ocean, influence ocean chemistry and atmospheric carbon dioxide. On the other hand, the way in which chemical elements get removed from ocean water should be just as important and will be the focus of my work supported by this fellowship.”
Yi’s research lab, an experimental condensed matter physics group, aims to advance the fundamental understanding of exotic properties in materials using spectroscopy tools such as angle-resolved photoemission spectroscopy and X-ray scattering.
“Materials that have exotic properties, such as superconductivity, can revolutionize our future,” Yi said. “My job is to figure out, from a fundamental physics point of view, why these materials have these amazing properties.”
New to Rice, Yi has been on campus since January. “I’m very excited to be at Rice, and I’m honored to receive this award,” she said. “In certain ways, I think it shows that the Rice community is very supportive of young professors, and it’s an encouragement for me to start my own group.”
With her fellowship support, Yi will focus on ways to control and tune exotic material properties. “As physicists, we like to figure out patterns, or overarching frameworks that describe a phenomenon,” she said. “Our goal is to figure out rules to describe and unify the things we see in nature.”
Torres earned a bachelor’s degree in geology from Pitzer College in 2010 and a Ph.D. in geochemistry from the University of Southern California in 2015. He joined Rice in 2017 from the California Institute of Technology.
Yi earned a bachelor’s degree in physics from the Massachusetts Institute of Technology in 2007 and a Ph.D. in physics from Stanford University in 2014. She joined Rice in 2018 from the University of California, Berkeley.
The Alfred P. Sloan Foundation is a philanthropic, not-for-profit, grant-making institution based in New York. Established in 1934 by Alfred Pritchard Sloan Jr., then-president and chief executive officer of General Motors Co., the foundation makes grants in support of original research and education in science, technology, engineering, mathematics and economics.
A Research Spotlight highlighting their paper, “Pacific Plate Apparent Polar Wander, Hot Spot Fixity, and True Polar Wander During the Formation of the Hawaiian Island and Seamount Chain From an Analysis of the Skewness of Magnetic Anomaly 20r (44 Ma)” has been published on Eos.org.