Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists find new carbon pollution called ’tar balls’

22.03.2004


An international team of scientists has discovered new carbon-bearing particles, which they call "tar balls," in air pollution over Hungary, the Indian Ocean, and southern Africa. Tar balls form in smoke from wood fires and agricultural and forest burning. Carbon-bearing particles like tar balls in the lower atmosphere are a concern, they say, because they may affect global climate change, as well as air quality.



The team, headed by Mihály Pósfai, an Earth and environmental science professor at the University of Veszprém in Hungary, completed the first comprehensive study of tar balls and report their findings this month in the Journal of Geophysical Research--Atmospheres, published by the American Geophysical Union.

"They are especially abundant in slightly aged--minutes to hours old--biomass [vegetal] smoke," says co-author Peter Buseck, a geochemist at Arizona State University. That means they probably formed from gases in smoke plumes, he says, and contain organic compounds that absorb sunlight. "Tar balls occur in a variety of atmospheric environments that are affected by human activities," he says.


At first glance, tar balls may look like soot, a common form of carbon pollution in the air, but when observed through an electron microscope, the differences become clear, the researchers say.

"Soot forms in the flame and consists of spheres," Pósfai says. Each soot sphere is made of graphitic layers that are concentrically wrapped like the layers of an onion and, with other soot spheres, forms chains or grape-like clusters, he says. Tar balls, on the other hand, are just individual spheres and do not form chains or clusters. They lack any internal structure and don’t have onion-like layers in them. "The internal structure affects the optical properties of the particle--the more ordered the graphitic structure, the darker the color," Pósfai explains. "Dark particles absorb sunlight and thereby heat the atmosphere." While black soot is the major absorber of sunlight in the atmosphere, tar balls may also be absorbing sunlight. "And this is significant," he says.


The research was supported by NASA, the U.S. National Science Foundation, and the Hungarian Science Foundation.

Harvey Leifert | American Geophysical Union
Further information:
http://www.agu.org/
http://www.agu.org/sci_soc/prrl/prrl0415.html

More articles from Earth Sciences:

nachricht Artificial Glaciers in Response to Climate Change?
10.08.2018 | Universität Heidelberg

nachricht Planet at risk of heading towards irreversible “Hothouse Earth” state
07.08.2018 | Potsdam-Institut für Klimafolgenforschung

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

Im Focus: A molecular switch may serve as new target point for cancer and diabetes therapies

If certain signaling cascades are misregulated, diseases like cancer, obesity and diabetes may occur. A mechanism recently discovered by scientists at the Leibniz- Forschungsinstitut für Molekulare Pharmakologie (FMP) in Berlin and at the University of Geneva has a crucial influence on such signaling cascades and may be an important key for the future development of therapies against these diseases. The results of the study have just been published in the prestigious scientific journal 'Molecular Cell'.

Cell growth and cell differentiation as well as the release and efficacy of hormones such as insulin depend on the presence of lipids. Lipids are small...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

NRL's sun imaging telescopes fly on NASA Parker Solar Probe

13.08.2018 | Physics and Astronomy

UT-ORNL team makes first particle accelerator beam measurement in six dimensions

13.08.2018 | Physics and Astronomy

ASU astrophysicist helps discover that ultrahot planets have starlike atmospheres

13.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>