Geobites – Page 4 – Down-to-Earth Geoscience Writing

July 25, 2022July 25, 2022

A Historical Link Between Thiamine Deficiency in Salmon and the Presence of Thiaminase in their Prey

Featured Image: A salmon in a stream on the Oregon coast. Photo credit: Conrad Gowell

Paper: Thiaminase activity of gastrointestinal contents of salmon and herring from the Baltic Sea

Authors: S. Wistbacka, A. Heinonen, and G. Bylund

Flintstones vitamins are generally marketed for children, but should fish be taking them too? Thiamine (vitamin B1) deficiency in fish, especially species of salmon, is a widespread issue with serious implications, as this vitamin is an integral compound required by virtually all living organisms. Vitamin B1 deficiency can lead to an array of negative health outcomes for salmon, which collectively manifest as the condition known as thiamine deficiency complex. This condition inhibits many salmon and other anadromous fish (those that migrate from the oceans to rivers to spawn) from spawning, posing a major problem for their long-term survival.

July 22, 2022July 22, 2022

What Makes a Supervolcano “Super”?

Featured Image: Yellowstone National Park attracts millions of people a year and has been a major focal point for discussions about supervolcanoes in recent decades. Public domain image via pixabay.

Paper: Capturing the Extreme in Volcanology: The Case for the Term “Supervolcano”

Authors: S. De Silva & S. Self

The earth sciences can be challenging to communicate. Definitions change over time and, in some cases, become widely reported in the media and often without a formal definition. A recent paper by Shanaka de Silva and Stephen Self addresses these issues surrounding the popular word “supervolcano.” The authors discuss the variables used to distinguish between these extreme events and regular eruptions. They then suggest a new working definition for researchers to use moving forward, clearing up much confusion that surrounds the word. The concept of supereruptions exploded in popularity after the 2005 Discovery TV/BBC documentary Supervolcano, promoted with the by-line “Is Yellowstone Overdue?“

June 30, 2022June 30, 2022

Is geothermal energy fit for megacities?

Featured image: Steam rising from Nesjavellir Geothermal Power Station in Iceland via Wikimedia commons. Public Domain.

Article: Geothermal energy as a means to decarbonize the energy mix of megacities

Authors: Carlos A. Vargas, Luca Caracciolo, Philip Ball

As the world grapples with climate change, the transition to renewable energy has become a necessity. Governments are investing heavily in solar and wind power to reduce the dependence on fossil fuels. Another non-conventional source of energy that’s still understudied is geothermal energy. But what is geothermal energy? Geo means earth, thermal means heat. The internal heat of Earth is harnessed to heat water and produce power. An advantage of using geothermal energy over solar and wind is that, it doesn’t rely on weather to produce electricity. It provides clean, constant, stable and predictable supply of power. The question is, can geothermal energy cater to the demand of megacities where a large chunk of the world’s population resides?

June 29, 2022June 29, 2022

Our enduring fascination with groundwater springs

Landscape with mountains in the distance and trees, rocks, and a path in the foreground

Featured Image: The middle zone of the Gerecse Mountains in Hungary via Wikimedia Commons. Public Domain.

Article: Springs regarded as hydraulic features and interpreted in the context of basin-scale groundwater flow
Authors: Tóth, Á., Kovács, S., Kovács, J., & Mádl-Szőnyi, J.

O Fount Bandusia, brighter than crystal,
worthy of sweet wine and flowers,
tomorrow shalt thou be honoured with
a firstling of the flock whose brow,

with horns just budding, foretokens love
and strife. Alas! in vain; for this
offspring of the sportive flock shall
dye thy cool waters with its own red blood.

Thee the fierce season of the blazing
dog-star cannot touch; to bullocks wearied
of the ploughshare and to the roaming flock
thou dost offer gracious coolness.

Thou, too, shalt be numbered among the
far-famed fountains, through the song I
sing of the oak planted o’er the grotto
whence thy babbling waters leap.

Horace (56BC-8BC) Ode 3.13

This ode by the Roman poet Horace is part of a long tradition of art and literature honoring groundwater springs, called ‘founts’ or ‘fountains’ in this translation. It is no wonder why: they can provide high-quality water that continues to flow even in the heat of a Mediterranean summer, “the fierce season of the blazing dog-star,” when surface water is often not available. But where does this water come from? Is it from large underground lakes, as the Romans suspected? Some of the same characteristics Horace names in this poem can help scientists figure this out.

June 18, 2022November 23, 2022

Ice from fire – When volcanos let it snow

Featuring image: Erruption of the Raikoke Volcano on June 22, 2019. Volcanos can exhaust a large amount of gases and dust during eruptions. Is this enough to create an atmosphere on the Moon? NASA’s Earth Observatory, public domain (CC0).

Paper: Polar Ice Accumulation from Volcanically Induced Transient Atmospheres on the Moon

Authors: A. X. Wilcoski, P. O. Hayne and M. E. Landis

The Moon is a silent and dry, yet beautiful desert. Where it comes from and how much ice exits is still a mystery. It can be found in the darkness of its pole regions as ice. Surprisingly, the eruptions of volcanos might have helped the Moon to keep its water.

The gas that is set free during a volcano eruption contains different volatile molecules, including water. On small celestial objects without an atmosphere like the moon, most of the gases are released to space. A new study suggests that not all water vapour from such eruptions escaped from the Moon during its history. Instead, local and short-lived atmospheres might have formed during eruptions, allowing a part of the water vapour to cool down and deposit as snow and ice.

June 1, 2022June 1, 2022

How Machine Learning Helps in the Fight Against Climate Change

Featured Image: Machine Learning has proven itself to be an effective tool in interdisciplinary research, but how can it be useful in understanding climate change? CC BY-NC 4.0, via. Dean Long

Paper: Tackling Climate Change with Machine Learning (Chapter 8)

Authors: David Rolnick et al.

Machine Learning (ML) gives researchers extremely valuable ways of revealing patterns within enormous datasets, and making predictions. Climate change research is one of many fields that is beginning to explore ML approaches. There are three major areas of interest: (1) climate prediction/modeling, (2) assessing impacts, and (3) exploring solutions as we attempt to decarbonize energy production. Rolnick and his coworkers explored the merit of machine learning in climate research and where it can support scientists best. The authors also call for greater collaboration between researchers of different backgrounds to advance our understanding of such a complex issue.

April 29, 2022April 29, 2022

Silver Doesn’t Grow on Trees: The Quest for the Ores that Formed Roman Coinage

Featured image: A silver Roman Denarius, featuring the likeness of emperor Marcus Aurelius. CC BY-SA 3.0 via Wikimedia Commons

Paper: Silver isotope and volatile trace element systematics in galena samples from the Iberian Peninsula and the quest for silver sources of Roman coinage

Authors: Jean Milot; Janne Blichert-Toft; Mariano Ayarzagüena Sanz; Chloé Malod-Dognin; Philippe Télouk; Francis Albarède

The Roman Empire was a superpower thousands of years ago, and with great power comes great (fiscal) responsibilities, including minting the money. To mint silver coins, the Romans needed vast amounts of silver, which historians and archeologists believe originated in the Iberian Peninsula, or present-day Spain and Portugal. However, the geologic origin of that silver is unknown as the depleted mines were abandoned long ago.

April 28, 2022April 28, 2022

Greenhouse gasses, ice cover, and the deep ocean shape Earth’s paleoclimate in unexpected ways

Featured Image: Line-scan image of sediment core from the Bay of Bengal. Image from the International Ocean Discovery Program. A. Volcanic ash associated with the Toba eruption. B. Pyrite-, foraminifer-, and shell fragment–rich sandy patch in foraminifer-rich clay with biosilica. C. Scaphopod in nannofossil-rich clay with foraminifers. D. Wood fragments in clay. E. Large dark gray burrow filled with the overlying sediment. F. Core disturbance (cracks) due to gas release when core liner was drilled on the catwalk. G. Minor core disturbance due to mud and water flow-in along the edges of the liner (~1 cm thickness).

Paper: Increased interglacial atmospheric CO₂ levels followed the mid-Pleistocene Transition

Authors: Masanobu Yamamoto, Steven C. Clemens, Osamu Seki, Yuko Tsuchiya, Yongsong Huang, Ryouta O’ishi, Ayako Abe-Ouchi

Mention of the ice age may conjure up images of giant mastodons, ferocious saber-tooth tigers, or of a prehistoric squirrel trying so desperately to secure his acorn—all taking place on the vast amount of ice that covered portions of the globe. We know that periods of ice cover followed by stretches of warm weather was a standard pattern in our Earth’s history*, but there was something special about the last ice age (during the Pleistocene) and how long it hung around.

April 27, 2022April 27, 2022

Methanotrophs: Nature’s catalytic converters

Featured image: A car exhaust pipe, by Matt Boitor on Unsplash.

Paper: Microbial methane oxidation efficiency and robustness during lake overturn

Authors: M. Zimmerman, M. Mayr, H. Bürgmann, W. Eugster, T. Steinsberger, B. Wehrli, A. Brand, D. Bouffard

If you own a car, you’re likely aware that your engine emits greenhouse gases to the atmosphere. Although we usually think of cars and other human activities as the primary source of such greenhouse gases, living ecosystems can also produce these gases through natural processes. For example, lakes are an important global source of methane, a potent greenhouse gas produced in lake sediments as organic matter decomposes. In their recent paper, Zimmerman and colleagues focus on a small but mighty team of microbes that work hard to limit the amount of methane emitted from lakes.

April 26, 2022April 26, 2022

How to connect methane in atmosphere to a planets geology and biology

Featuring image: Titan’s atmosphere is rich in organic molecules, but we still don’t know if there is life on Saturn’s icy moon. With JWST and the coming generation of telescopes, we will be able to observe the atmospheres of exoplanets. Is there a way to search for life on these distant worlds? NASA/JPL, public domain (CC0).

Paper: The case and context for atmospheric methane as an exoplanet biosignature

Authors: M. A. Thompson, J. Krissansen-Totton, N. Wogan, M. Telus and J. J. Fortney

Visiting and exploring exoplanets for extraterrestrial life still belong to the realm of science fiction. However, the coming generation of telescopes will enable us to look into the atmospheres of exoplanets and search for possible biosignatures, chemical compounds that could indicate the presence of life.

Searching for life on a planet is not a trivial task. Since the first Mars landing in 1976, scientists still search for recent or ancient traces of life. It becomes even more difficult on planets that we cannot directly visit. The next telescope generation will enable us to observe the atmosphere of distant planets remotely. Are there ways to find evidence of life in a planet’s atmosphere? A new study suggests that the freshly launched James Webb Space Telescope (JWST) could help us to search for life on other worlds.