Hunting for phosphorus on early Earth

Featured Image: A sample of the mineral schreibersite, a possible source of meteoric phosphorus. CC-BY 3.0, via Wikimedia commons.

Paper: Phosphorus mineral evolution and prebiotic chemistry: From minerals to microbes

Authors: Craig R. Walton, Oliver Shorttle, Frances E. Jenner, Helen M. Williams, Joshua Golden, Shaunna M. Morrison, Robert T. Downs, Aubrey Zerkle, Robert M. Hazen, Matthew Pasek

With a swift strike, a match bursts into flame. Life, like the flame, burst into existence almost 4 billion years ago, and as with the sparking of the match, phosphorus was a key ingredient. Phosphorus, element 15, is at the center of energy production in cells, forms cell walls, and provides the backbone for DNA.

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It’s magnetic! Probing the predictability of ancient rainfall using a mountainous ridge of red stone

Featured image: From Fig. 1 in Ao et al. (2021). An image of the Late Oligocene-age red mudstone that is the subject of this study, between bracketing sandstone sections. This mudstone outcrop (known as the Duittingou section) is located in the Lanzhou Basin, China, in the northeastern Tibetan Plateau. Image licensed under CC BY-NC.

Paper: Eccentricity-paced monsoon variability on the northeastern Tibetan Plateau in the Late Oligocene high CO2 world

Authors: Hong Ao, Diederik Liebrand, Mark J. Dekkers, Peng Zhang, Yougui Song, Qingsong Liu, Tara Jonell, Qiang Sun, Xinzhou Li, Xinxia Li, Xiaoke Qiang, Zhisheng An

The intensity and frequency of rainfall affects food supply around the world, the structural integrity of buildings and homes, and flooding in the impermeable “concrete jungles” of cities. However, not much is known about how rainfall has fluctuated naturally in the distant past, making it more difficult for scientists to predict how climate change will affect future precipitation. Recently, an international team of authors addressed a small part of this problem by uncovering how rainfall in Asia changed under different climates far back in time. Their scientific adventure started once they identified a particularly special rock formation in China, where invisible traces of ancient rainfall had been preserved.

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Do we need new types of geology to understand exoplanets?

Featuring image: White dwarf make perfect natural mass spectrometer, more powerful as any instrument on Earth. Can they help us to learn about exoplanets? NOIRLab/NSF/AURA/J. da Silva, Creative Common (CC BY 4.0)

Paper: Polluted white dwarfs reveal exotic mantle rock types on exoplanets in our solar neighborhood

Authors: K. D. Putirka and S. Xu

For a long time, geologist were only able to study rocks on the ground. We extended this knowledge to our neighbouring planets. Now finally, scientist have found a way to study rocks from planets far away, using the light of their host stars. And they look very strange.

Over the last 30 years, exoplanets have evolved from mere theory into a fantastic reality. Today we know that nearly all stars host at least one exoplanet and even exoplanets with an Earth-like mass are relatively common. Still, we know very little about the geology of these worlds. In a new study, Keith Putirka and Siyi Xu were able to observe and compare the mineralogy of exoplanets to that of the rocky planets in the solar system. Surprisingly, these exoplanets exhibit types of mineralogy unlike any we have known before.

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Metal-Eating Microbes Who Breathe Methane

Featured Image: Murky pond in Alaska with “rusty” iron-filled sediments. Image courtesy Jessica Buser. Used with permission.

Paper:  Sulfate- and iron-dependent anaerobic methane oxidation occurring side-by-side in freshwater lake sediment

Authors: Alina Mostovaya, Michael Wind-Hansen, Paul Rousteau, Laura A. Bristow, Bo Thamdrup

The table has been set and the food is all prepared. But this is no ordinary dinner party, it’s a microbe party! The guests sit down and proceed to dig into the main course; sulfur, rusty iron, and methane. Curiously, the guests are feeding each other, not themselves! This image seems pretty weird to us humans, but it’s a delight to these microbes. This collaborative method of eating occurs in pond and lake mud all around the world. In a new study, Mostovaya and colleagues describe one such feast in Danish Lake Ørn, that is not only collaborative but may mitigate climate change.

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Carbon to carbonates: capturing CO2 with rocks

Featured image: a field of basalt in Hawai’i Volcanoes National Park (National Park Service, public domain)

Paper: Potential CO2 removal from enhanced weathering by ecosystem respnses to powdered rock
Authors: Daniel S. Goll et al.

In the 2015 Paris Agreement, nations pledged to work toward a common goal of limiting global warming to less than 2°C compared to pre-industrial times. The Agreement doesn’t specify how the signatories should do this, though: levy a carbon tax? Shut down coal-fired power plants? Use a stainless steel straw? According to the best available climate science, we will need to be doing all of the above and then some. In fact, meeting the target of the Paris Agreement will require negative emissions, removing greenhouse gases from the atmosphere via some form of Negative Emissions Technology (NET).

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How did giant impacts influence our atmosphere?

Featuring image: Oxygen was not always present in Earth’s atmosphere, but stated to accumulate only around 3.5 billion years ago. Pixabay, Public Domain (CC0)

Paper: Delayed and variable late Archaean atmospheric oxidation due to high collision rates on Earth

Authors: S. Marchi, N. Drabon, T. Schulz, L. Schaefer, D. Nesvorny, W. F. Bottke, C. Koeberl and T. Lyons

Take a deep breath. Your lungs fill with air and vital oxygen. Not only you, but all higher life depends on oxygen. In the Archean aeon, which lasted from 4 to 2.5 billion years before present, Earth’s atmosphere contained no oxygen. How did oxygen accumulate in the atmosphere? A team of researchers discovered that the evolution of our atmosphere was strongly influenced by impacts of large meteorites when our planet was still young.

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Pipe Dreams: stories of Bengaluru’s water supply

Featured Image: Raj Bhagatt P (published with permission from the author)

Castán Broto, V., Sudhira, H. and Unnikrishnan, H. (2021), WALK THE PIPELINE: Urban Infrastructure Landscapes in Bengaluru’s Long Twentieth Century. Int. J. Urban Reg. Res., 45: 696-715. https://doi.org/10.1111/1468-2427.12985

Can a pipeline that runs through an urban landscape weave narratives of water usage through space and time? A beautiful article published in the International Journal of Urban and Regional Research captures some of the stories along the oldest pipeline in Bengaluru, South India. The narratives talk of the urban and rural divide, the patterns of urban sprawl, the pre-colonial water management, and the scarcity faced today.

Before the pipeline, Bengaluru relied on an ancient network of seasonally-replenished tanks, reservoirs and open wells for its agrarian water supply. This network was engineered to harness the natural gradients of Bengaluru’s topography, and to ensure water reached different parts of the city. In 1894, the Chamarajendra waterworks laid down the first modern iron pipeline to source water from the Arkavathi river to Bengaluru’s colonial heart – and history was made. Based on old planning records and an analysis of historic maps, this pipeline today can be traced from the low-level reservoir at the heart of Bengaluru, passing through the neighbourhoods of Malleshwaram, Yeshwanthpur, and Dasarahalli, ending at the Hesaraghatta tank at the northwest corner of the city. Throughout history, the pipeline has affected the lives of people and other urban infrastructure along the way, and continues to do so.

Landmarks along the oldest pipeline in Bengaluru today. Image credits: H.S. Sudhira. Image source: https://doi.org/10.1111/1468-2427.12985

In the 1960s, the Bangalore Water Supply and Sewerage Board (BWSSB) was created to meet the demands of the city. Yet with the ever-expanding urban stretches and the burgeoning population, water scarcity is among the major challenges faced by Bengaluru today. Pipelines from Tarabanahalli, and from Shivanasamudra, along with the old one from Hesaraghatta, transfer water from the rural outskirts to the heart of Bengaluru. In addition, groundwater resources and some water from the Arkavathi river is carried by tankers into the city, to supplement the 6,000 public borewells, and roughly 50,000 residential borewells. Despite water conservation efforts like rainwater harvesting and recycling, the water scarcity in Bengaluru has begun to have ecological and environmental impacts – and the impact will be disproportionately felt by the low-income groups, who can not afford private borewells, nor the cost of long-distance transfers.

A 1914 map of Bengaluru by Baedekar showing some of the old tanks in the heart of the city. In the colonial era, as a cantonment, tanks and wells served much of the city’s water demands. Image: public domain.

The article goes on to reflect on the historical, socio-economic, and political aspects of the neighbourhoods through which the pipeline flows – almost like a travelogue with a bitter note. As the pipeline networks developed, they created a set of conditions for residential and industrial development. Some neighbourhoods benefit directly from the pipeline, whereas some don’t, and over time the pipeline has further marginalized the poorer populations from receiving a good supply of water. These disparities will only get starker in the years to come. Residential overcrowding, land misappropriation, pollution, and increasing demand for industry and residences affect the efficiency of the water network and strain the groundwater resources. As more technological solutions are sought, the local ecologies that sustained these past water systems – such as agricultural patches that helped replenish tanks, the numerous rainwater-filled lakes that have since disappeared due to encroachment, or are severely polluted and littered, have been ignored.

The article underlines a harsh truth – Bengaluru never had enough water. If we are to strategize our water infrastructures again, we need new technological approaches, new resources or to reverse the direction of services from the peri-urban area to the centre of the city and vice versa, with due cognizance of encroachment and violations by existing and future development. The traditional system of tanks and wells needs to be integrated into the broader network of water resources to meet the needs of an ever-expanding urban nexus.


Pipe Dreams: stories of Bengaluru’s water supply by Devayani Khare is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

Highway Maintenance “Drives” Carbon Release in Forests

Featured Image: Forest and highway between Trójmiasto and Gdynia, Northern Poland. Image courtesy Robin Hammam.

Paper: The proximity of a highway increases CO2 respiration in forest soil and decreases the stability of soil organic matter

Authors: Dawid Kupka, Mateusz Kania, Piotr Gruba

There has been a lot of talk about transportation as of late with America’s “Build Back Better Act”.  While these political decisions are partially informed by scientific research around climate change, particularly in the United States (where 30% of greenhouse gas emissions result from transportation by road, rail, and air each year), the negative impacts of transportation infrastructure on the climate and local ecosystems are often lost in political discussions.  In a new study in Scientific Reports, Kupka and colleagues discuss the broader impacts of highway maintenance on nearby forest soil ecosystems, finding that roadways themselves can increase carbon dioxide emissions by disrupting local carbon cycles.

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The Charney Report vs IPCC6: What’s changed in climate science in the last 40 years?

NASA satellite image of Earth from space, showing California wildfire smoke visible in the atmosphere.

Papers: Carbon Dioxide and Climate, a Scientific Assessment by Charney et. al (1979);
Climate Change 2021: The Physical Science Basis by the IPCC (2021)

Right now in Glasgow, Scotland, representatives of world governments and other parties are currently gathering yet again to negotiate political solutions to climate change at COP26. This is the 26th semi-annual Conference of the Parties on climate change, but the history of our understanding of the problem — and attempts to deal with it — goes back even further than that. Speaking strictly of the science of global warming and its effects, what do we know now that the participants of the first COP did not?

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Ancient Explosive Volcanoes on Mars

Featured image: a mushroom shaped volcanic plume arising from the explosive activity of Redoubt volcano, Alaska in 1990. Credit: R. Clucas.

Paper: Caldera Collapse and Volcanic Resurfacing in Arabia Terra Provide Hints of Vast Under-Recognized Early Martian Volcanism

Authors: Yin Yau Yoyo Chu, Joseph R. Michalski, Shawn P. Wright, A. Alexander G. Webb.

Mars is a planet of extreme highs and lows containing the solar system’s largest volcano – Olympus Mons – and the largest canyon system – Valles Marineris. Tharsis and Elysium, the planet’s two largest volcanic provinces, are young surface features that were built by basaltic volcanism throughout the Amazonian, the most recent geological era on Mars.

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