Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Atmospheric science goes to ground: Researchers present new findings on the natural hydrogen cycle


New evidence suggest earth’s soil may be as important as its atmosphere

New evidence is emerging on the probable effects of an anticipated reliance on hydrogen as a fuel: surprisingly, we may need to look down in the ground rather up in the air, for answers.

In the August 21 issue of the journal Nature, a group of researchers from the California Institute of Technology and other institutions reports results of a study of the atmospheric chemical reactions that produce and destroy hydrogen in the stratosphere. Funded in part by the National Science Foundation (NSF), the study concludes that most of the hydrogen eliminated from the atmosphere goes into the ground, and therefore that scientists will need to turn their focus toward developing an understanding of soil destruction of hydrogen to accurately predict whether hydrogen emissions will eventually accumulate in the air.

The researchers reached this conclusion after carefully measuring the abundance of a rare isotope of hydrogen known as deuterium. It has long been known that atmospheric hydrogen is rich in deuterium, but it was unclear why. The only reasonable explanation, scientists believed, is that atmospheric hydrogen is mostly destroyed by chemical reactions in the air, and that those reactions are relatively slow for deuterium-rich hydrogen, so it accumulates like salt in an evaporating pan of water.

If correct, this would mean that oxidizing atmospheric trace gases control the natural hydrogen cycle and that soils are relatively unimportant. But new research results suggest that one of the main natural sources of atmospheric hydrogen--the breakdown of methane--is actually responsible for the atmosphere’s enrichment in deuterium. This result implies that reactions with atmospheric oxidants may be less important to the hydrogen cycle, and that uptake by soils, where microbial processes involve methane, is the driving force.

Hydrogen is a highly reactive element, but answers to the questions of when and where it reacts, and under what circumstances, are difficult to unravel. These questions are simplified in the stratosphere, where it’s easier to single out and understand specific reactions. According to John Eiler, a geochemist at the California Institute of Technology and an author of the Nature paper, the new data were gathered from air samples taken from the stratosphere with one of the high-flying ER-2 planes operated by the NASA Dryden Flight Research Center in the Mojave Desert.

"We wanted to look at hydrogen in the stratosphere because it’s easy to study the production of hydrogen from methane separate from other influences," Eiler explains. "It may seem odd to go to the stratosphere to understand what’s happening in the ground, but this was the best way to get a global perspective on the importance of soils to the hydrogen cycle."

With precise information on the deuterium content of hydrogen formed from methane, the researchers were able to calculate that the soil uptake of hydrogen is as high as 80 percent. It is suspected that this hydrogen is used by soil-living microbes to carry on their biological functions, although the details of this process are poorly understood and have been the subject of only a few previous studies.

It seems likely, according to the scientists, that the hydrogen taken up by soils is relatively free of environmental consequences, but the question still remains of how much more hydrogen the soil can "consume." If future use of hydrogen in transportation results in a significant amount of leakage, then soil uptake must increase dramatically or it will be inadequate to cleanse the released hydrogen from the atmosphere, Eiler says.

"An analogy would be the discovery that trees and other plants get rid of some of the carbon dioxide that cars emit, but by no means all of it," he says. "So the question as we look toward a future hydrogen economy is whether [soil] microbes will be able to ’eat’ the hydrogen fast enough."

Bruce Doddridge, program director in NSF’s division of atmospheric sciences, which co-funded the research, said, "This carefully conducted research investigating the natural chemistry of sources and sinks affecting the abundance of hydrogen in the atmosphere results in the most accurate information to date, and appears to account for the atmospheric deuterium excess previously observed.

"A more accurate molecular hydrogen budget may have important implications as global fuel technology shifts its focus from fossil fuels to other sources," Doddridge added.

The lead author of the paper is Thom Rahn, a former post-doctoral fellow of Eiler’s who is now affiliated with Los Alamos National Laboratory. The other authors are Paul Wennberg, an atmospheric chemist at Caltech; Kristie A. Boering and Michael McCarthy, both of UC Berkeley; Stanley Tyler of UC Irvine; and Sue Schauffler of the National Center for Atmospheric Research in Boulder, Colorado.

In addition to NSF, an independent federal agency that supports fundamental research in science and engineering, other supporters of the research were the Davidow Fund and General Motors Corp., the David and Lucile Packard Foundation, the NASA Upper Atmosphere Research Program, and the National Center for Atmospheric Research.

NSF PR 03-87

NSF Program Contact: Bruce Doddridge, 703-292-8522,
Caltech Media Contact: Robert Tindol, 626-395-3631,

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering, with an annual budget of nearly $5.3 billion. NSF funds research all 50 states through grants to nearly 2,000 universities and institutions. Each year, NSF receives about 30,000 competitive requests for funding, and makes about 10,000 new funding awards. The NSF also awards over $200 million in professional and service contracts yearly.

Cheryl Dybas | NSF
Further information:

More articles from Earth Sciences:

nachricht Receding glaciers in Bolivia leave communities at risk
20.10.2016 | European Geosciences Union

nachricht UM researchers study vast carbon residue of ocean life
19.10.2016 | University of Miami Rosenstiel School of Marine & Atmospheric Science

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>