Tag Archives: organic carbon

River Buries Permafrost Carbon at Sea

New study traces the fate of carbon stored in thawing Arctic soils

As temperatures rise, some of the organic carbon stored in Arctic permafrost meets an unexpected fate—burial at sea. As many as 2.2 million metric tons of organic carbon per year are swept along by a single river system into Arctic Ocean sediment, according to a new study an international team of researchers published in Nature. This process locks away carbon dioxide (CO2) – a greenhouse gas – and helps stabilize the earth’s CO2 levels over time, and it may help scientists better predict how the natural carbon cycle will interplay with the surge of CO2 emissions due to human activities. (more…)

Read More

A Living Desert Underground

In the perpetual darkness of a limestone cave, UA researchers have discovered a surprisingly diverse ecosystem of microbes eking out a living from not much more than drip water, rock and air. The discovery not only expands our understanding of how microbes manage to colonize every niche on the planet but also could lead to applications ranging from environmental cleanup solutions to drug development.

Hidden underneath the hilly grasslands studded with ocotillos and mesquite trees in southeastern Arizona lies a world shrouded in perpetual darkness: Kartchner Caverns, a limestone cave system renowned for its untouched cave formations, sculpted over millennia by groundwater dissolving the bedrock and carving out underground rooms, and passages that attract tourists from all over the world.  (more…)

Read More

How Did Earth’s Primitive Chemistry Get Kick Started?

How did life on Earth get started? Three new papers co-authored by Mike Russell, a research scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., strengthen the case that Earth’s first life began at alkaline hydrothermal vents at the bottom of oceans. Scientists are interested in understanding early life on Earth because if we ever hope to find life on other worlds — especially icy worlds with subsurface oceans such as Jupiter’s moon Europa and Saturn’s Enceladus — we need to know what chemical signatures to look for.

Two papers published recently in the journal Philosophical Transactions of the Royal Society B provide more detail on the chemical and precursor metabolic reactions that have to take place to pave the pathway for life. Russell and his co-authors describe how the interactions between the earliest oceans and alkaline hydrothermal fluids likely produced acetate (comparable to vinegar). The acetate is a product of methane and hydrogen from the alkaline hydrothermal vents and carbon dioxide dissolved in the surrounding ocean. Once this early chemical pathway was forged, acetate could become the basis of other biological molecules. They also describe how two kinds of “nano-engines” that create organic carbon and polymers — energy currency of the first cells — could have been assembled from inorganic minerals. (more…)

Read More

Where Does Charcoal, or Black Carbon, in Soils Go?

Scientists find surprising new answers in wetlands such as the Everglades

Scientists have uncovered one of nature’s long-kept secrets–the true fate of charcoal in the world’s soils.

The ability to determine the fate of charcoal is critical to knowledge of the global carbon budget, which in turn can help understand and mitigate climate change.

However, until now, researchers only had scientific guesses about what happens to charcoal once it’s incorporated into soil. They believed it stayed there.

Surprisingly, most of these researchers were wrong. (more…)

Read More

Salt Seeds Clouds in the Amazon Rainforest

It’s morning, deep in the Amazon jungle. In the still air innumerable leaves glisten with moisture, and fog drifts through the trees. As the sun rises, clouds appear and float across the forest canopy … but where do they come from? Water vapor needs soluble particles to condense on. Airborne particles are the seeds of liquid droplets in fog, mist, and clouds.

To learn how aerosol particles form in the Amazon, Mary Gilles of the Chemical Sciences Division at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and David Kilcoyne of the Lab’s Advanced Light Source (ALS) worked with Christopher Pöhlker of Germany’s Max Planck Institute for Chemistry (MPIC) as part of an international team of scientists led by MPIC’s Meinrat Andreae and Ulrich Pöschl. They analyzed samples of naturally formed aerosols collected above the forest floor, deep in the rainforest. (more…)

Read More

New Study by WHOI Scientists Provides Baseline Measurements of Carbon in Arctic Ocean

Scientists from the Woods Hole Oceanographic Institution (WHOI) have conducted a new study to measure levels of carbon at various depths in the Arctic Ocean. The study, recently published in the journal Biogeosciences, provides data that will help researchers better understand the Arctic Ocean’s carbon cycle—the pathway through which carbon enters and is used by the marine ecosystem. It will also offer an important point of reference for determining how those levels of carbon change over time, and how the ecosystem responds to rising global temperatures.

“Carbon is the currency of life. Where carbon is coming from, which organisms are using it, how they’re giving off carbon themselves—these things say a lot about how an ocean ecosystem works,” says David Griffith, the lead author on the study. “If warming temperatures perturb the Arctic Ocean, the way that carbon cycles through that system may change.” (more…)

Read More