Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA satellite tracks ozone pollution by monitoring its key ingredients

07.11.2017

Ozone pollution near Earth's surface is one of the main ingredients of summertime smog. It is also not directly measurable from space due to the abundance of ozone higher in the atmosphere, which obscures measurements of surface ozone. New NASA-funded research has devised a way to use satellite measurements of the precursor gases that contribute to ozone formation to differentiate among three different sets of conditions that lead to its production. These observations may also assist air quality managers in assessing the most effective approaches to emission reduction programs that will improve air quality.

Unlike its presence at high altitude where ozone acts as Earth's sunscreen from harmful ultraviolet radiation, at low altitudes, ozone is a health hazard contributing to respiratory problems like asthma and bronchitis.


The top row of images show each region in 2005, which had abundant NOx in urban areas where human emissions are high, leading to systems where ozone formation was controlled by VOC amounts. As pollution controls were put into place on NOx emissions, by 2015, the systems in Europe, the United States, and East Asian urban areas became limited by NOx, meaning that further controls on NOx would help reduce ozone formation. With the industrial growth of the last decade, the results in China outside the major cities show an increase in areas transitioning to being controlled by VOC amounts.

Credit: NASA

It is formed through complex chemical reactions initiated by sunlight and involving two types of gases, volatile organic compounds (VOC) and nitrogen oxides (NOx). Both are represented in the study by a major gas of each type, the VOC formaldehyde and NO2, that are measureable from space by the Dutch-Finnish Ozone Monitoring Instrument aboard NASA's Aura satellite, launched in 2004.

"We're using satellite data to analyze the chemistry of ozone from space," said lead author Xiaomeng Jin at the Lamont-Doherty Earth Observatory at Columbia University in Palisades, New York. Their research was published in Journal of Geophysical Research: Atmospheres, a publication of the American Geophysical Union.

With a combination of computer models and space-based observations, she and her colleagues used the concentrations of ozone's precursor molecules to infer whether ozone production increases more in the presence of NOx, VOCs, or a mix of the two, for a given location. Their study regions focused on North America, Europe and East Asia during the summer months, when abundant sunlight triggers the highest rates of ozone formation.

To understand their impact on ozone formation, Jin and her team investigated whether VOC or NOx was the ingredient that most limited ozone formation. If emissions of that molecule are reduced, then ozone formation will be reduced -- critical information for air quality managers.

"We are asking, 'If I could reduce either VOCs or NOx, which one is going to get me the biggest bang for my buck in terms of the amount of ozone that we can prevent from being formed in the lower atmosphere?'" said co-author and atmospheric chemist Arlene Fiore at Lamont-Doherty, who is also a member of NASA's Health and Air Quality Applied Sciences Team that partially funded this work and fosters collaboration between scientists and air quality managers.

The findings show that cities in North America, Europe and East Asia, are more often VOC-limited or in a transitional state between VOC and NOx-limited. In addition, the 12-year data record of satellite observations show that a location's circumstances can change. For instance, in 2005 New York City's ozone production during the warm season was limited by VOCs, but by 2015 it had transitioned to a NOx-limited system due to reduced NOx emissions resulting from controls put into place at both regional and national levels. This transition means that future NOx reductions will likely further decrease ozone production, said Jin.

Volatile organic compounds occur in high volume naturally, given off by some plants, including certain tree species. They can also arise from paint fumes, cleaning products, and pesticides, and are a by-product of burning fossil fuels in factories and automobiles. Nitrogen oxides are a byproduct of burning fossil fuels and are abundant in cities, produced by power plants, factories, and cars. Because VOCs have a large natural source during summer over the eastern United States, for example, emission reduction plans over the last two decades in this region have focused on NOx, which is overwhelmingly produced by human activities.

Space-based methods for monitoring ozone chemistry complement surface-based measurements made by air quality management agencies. The view from space offers consistent coverage of broad areas, and provides data for regions that may not have ground stations.

###

To read the paper, visit: http://onlinelibrary.wiley.com/doi/10.1002/2017JD026720/abstract

This work was a collaboration of researchers at Lamont-Doherty with those at University of Rochester in New York; the Royal Netherlands Meteorological Institute in De Bilt, Netherlands; Wageningen University in Wageningen, Netherlands; Belgian Institute for Space Aeronomy in Brussels, Belgium; Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; the U.S. Environmental Protection Agency Office of Research and Development in Research Triangle Park in North Carolina and its Region 8 Office in Denver Colorado; and NASA's Goddard Space Flight Center in Greenbelt, Maryland.

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

Rob Gutro | EurekAlert!

More articles from Earth Sciences:

nachricht Hundreds of bubble streams link biology, seismology off Washington's coast
22.03.2019 | University of Washington

nachricht Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>