Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fires burning in Africa and Asia cause high ozone in tropical Pacific

13.01.2016

Study indicates 'biomass burning' may play larger role in climate change than previously realized

As decision makers from around the world congregated in Paris to prepare a global climate agreement at the 21st Conference of the Parties (COP21), many discussions focused on how to reduce greenhouse gases, including ozone.


Two research planes on complementary missions flew over Guam measuring the levels of dozens of chemicals in the atmosphere in January and February 2014. The British Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft flew during the U.K. Natural Environment Research Council Coordinated Airborne Studies in the Tropics (CAST) mission. The aircraft that flew during the CONvective Transport of Active Species in the Tropics (CONTRAST) mission was the HIAPER (High-performance Instrumented Airborne Platform for Environmental Research), a Gulfstream V jet sponsored by the National Science Foundation and the National Center for Atmospheric Research and modified for advanced research. Taken together, the data collected by the two aircraft gave research collaborators a detailed view of air masses spanning tens of thousands of feet from the ocean surface to the stratosphere.

Credit: Loretta Kuo/Shawn Honomichl

While efforts to limit ozone precursor emissions tend to focus on industrial activities and fossil fuel combustion in the United States and China, a new study suggests that future regulations may need to address the burning of forests and vegetation. The study, which was published online January 13, 2016 in the journal Nature Communications, indicates that these types of "biomass burning" may play a larger role in climate change than previously realized.

Based on observations from two aircraft missions, satellite data and a variety of models, an international research team showed that fires burning in tropical Africa and Southeast Asia caused pockets of high ozone and low water in the lower atmosphere above Guam--a remote island in the Pacific Ocean 1,700 miles east of Taiwan.

... more about:
»Atmosphere »Atmospheric »ozone

"We were very surprised to find high concentrations of ozone and chemicals that we know are only emitted by fires in the air around Guam," said the study's lead author Daniel Anderson, a graduate student in the University of Maryland Department of Atmospheric and Oceanic Science. "We didn't make specific flights to target high-ozone areas--they were so omnipresent that no matter where we flew, we found them."

For the study, two research planes on complementary missions flew over Guam measuring the levels of dozens of chemicals in the atmosphere in January and February 2014. One aircraft flew up to 24,000 feet above the ocean surface during the U.K. Natural Environment Research Council's Coordinated Airborne Studies in the Tropics (CAST) mission. The other flew up to 48,000 feet above the ocean surface during the CONvective Transport of Active Species in the Tropics (CONTRAST) mission.

"International collaboration is essential for studying global environmental issues these days," said CAST Principal Investigator Neil Harris of the University of Cambridge Department of Chemistry. "This U.S./U.K.-led campaign over the western Pacific was the first of its kind in this region and collected a unique data set. The measurements are now starting to produce insight into how the composition of the remote tropical atmosphere is affected by human activities occurring nearly halfway around the world."

Researchers examined 17 CAST and 11 CONTRAST flights and compiled over 3,000 samples from high-ozone, low-water air parcels for the study. In the samples, the team detected high concentrations of chemicals associated with biomass burning--hydrogen cyanide, acetonitrile, benzene and ethyne.

"Hydrogen cyanide and acetonitrile were the smoking guns because they are emitted almost exclusively by biomass burning. High levels of the other chemicals simply added further weight to the findings," said study co-author Julie Nicely, a graduate student in the UMD Department of Chemistry and Biochemistry.

Next, the researchers traced the polluted air parcels backward 10 days, using the National Oceanic and Atmospheric Administration (NOAA) Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model and precipitation data, to determine where they came from. Overlaying fire data from NASA's moderate resolution imaging spectroradiometer (MODIS) onboard the Terra satellite, the researchers connected nearly all of the high-ozone, low-water structures to tropical regions with active biomass burning in tropical Africa and Southeast Asia.

"The investigation utilized a variety of models, including the NCAR CAM-Chem model to forecast and later analyze chemical and dynamical conditions near Guam, as well as satellite data from numerous instruments that augmented the interpretation of the aircraft observations," said study co-author Douglas Kinnison, a project scientist at the University Corporation for Atmospheric Research.

In the paper, the researchers also offer a new explanation for the dry nature of the polluted air parcels.

"Our results challenge the explanation atmospheric scientists commonly offer for pockets of high ozone and low water: that these zones result from the air having descended from the stratosphere where air is colder and dryer than elsewhere," said UMD Professor Ross Salawitch, the study's senior author and principal investigator of CONTRAST. Salawitch holds joint appointments in the university's Department of Atmospheric and Oceanic Science, Department of Chemistry and Biochemistry, and Earth System Science Interdisciplinary Center.

"We know that the polluted air did not mix with air in the stratosphere to dry out because we found combined elevated levels of carbon monoxide, nitric oxide and ozone in our air samples, but air in the higher stratosphere does not contain much naturally occurring carbon monoxide," said Anderson.

The researchers found that the polluted air that reached Guam never entered the stratosphere and instead simply dried out during its descent within the lower atmosphere. While textbooks show air moving upward in the tropics, according to Salawitch, this represents the net motion of air. Because this upward motion happens mostly within small storm systems, it must be balanced by air slowly descending, such as with these polluted parcels released from fires.

Based on the results of this study, global climate models may need to be reassessed to include and correctly represent the impacts of biomass burning, deforestation and reforestation, according to Salawitch. Also, future studies such as NASA's upcoming Atmospheric Tomography Mission will add to the data collected by CAST and CONTRAST to help obtain a clearer picture of our changing environment.

###

In addition to those mentioned above, the study's authors included UMD Department of Atmospheric and Oceanic Science Professor Russell Dickerson and Assistant Research Professor Timothy Canty; CAST co-principal investigator James Lee of the University of York (U.K.); CONTRAST co-principal investigator Elliott Atlas of the University of Miami; and additional researchers from NASA; NOAA; the University of California, Irvine; the California Institute of Technology; the University of Manchester (U.K.); the Institute of Physical Chemistry Rocasolano; and the National Research Council in Argentina.

This research was supported by the Natural Environment Research Council, National Science Foundation, NASA, and National Oceanic and Atmospheric Administration. The content of this article does not necessarily reflect the views of these organizations.

The research paper, "A pervasive role for biomass burning in tropical high ozone/low water structures" by Daniel C. Anderson et al., was published on January 13, 2016, in the journal Nature Communications.

Media Relations Contact: Abby Robinson, 301-405-5845, abbyr@umd.edu

Writer: Abby Robinson

University of Maryland
College of Computer, Mathematical, and Natural Sciences
2300 Symons Hall
College Park, MD 20742
http://www.cmns.umd.edu
@UMDscience

About the College of Computer, Mathematical, and Natural Sciences

The College of Computer, Mathematical, and Natural Sciences at the University of Maryland educates more than 7,000 future scientific leaders in its undergraduate and graduate programs each year. The college's 10 departments and more than a dozen interdisciplinary research centers foster scientific discovery with annual sponsored research funding exceeding $150 million.

Media Contact

Abby Robinson
abbyr@umd.edu
301-405-5845

 @UMDRightNow

http://www.newsdesk.umd.edu/ 

Abby Robinson | EurekAlert!

Further reports about: Atmosphere Atmospheric ozone

More articles from Earth Sciences:

nachricht Biomass turnover time in ecosystems is halved by land use
23.08.2016 | Alpen-Adria-Universität Klagenfurt

nachricht Diversity of habitats at natural oil seeps
22.08.2016 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: X-ray optics on a chip

Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.

In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...

Im Focus: Piggyback battery for microchips: TU Graz researchers develop new battery concept

Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.

Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...

Im Focus: UCI physicists confirm possible discovery of fifth force of nature

Light particle could be key to understanding dark matter in universe

Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...

Im Focus: Wi-fi from lasers

White light from lasers demonstrates data speeds of up to 2 GB/s

A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.

Im Focus: Every atom counts

Malignant cancer cells not only proliferate faster than most body cells. They are also more dependent on the most important cellular garbage disposal unit, the proteasome, which degrades defective proteins. Therapies for some types of cancer exploit this dependence: Patients are treated with inhibitors, which block the proteasome. The ensuing pile-up of junk overwhelms the cancer cell, ultimately killing it. Scientists have now succeeded in determining the human proteasome’s 3D structure in unprecedented detail and have deciphered the mechanism by which inhibitors block the proteasome. Their results will pave the way to develop more effective proteasome inhibitors for cancer therapy.

In order to understand how cellular machines such as the proteasome work, it is essential to determine their three-dimensional structure in detail. With its...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

A week of excellence: 22 of the world’s best computer scientists and mathematicians in Heidelberg

12.08.2016 | Event News

Towards the connected, automated and electrified automobiles: AMAA conference in Brussels

02.08.2016 | Event News

Clash of Realities 2016: 7th Conference on the Art, Technology and Theory of Digital Games

29.07.2016 | Event News

 
Latest News

New microchip demonstrates efficiency and scalable design

23.08.2016 | Information Technology

Genetic Regulation of the Thymus Function Identified

23.08.2016 | Life Sciences

Biomass turnover time in ecosystems is halved by land use

23.08.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>