Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Wildfires Cause Ozone Pollution to Violate Health Standards

13.10.2008
Wildfires can boost ozone pollution to levels that violate U.S. health standards, a new study concludes.

The research, by scientists at the National Center for Atmospheric Research (NCAR), focused on California wildfires in 2007, finding that they repeatedly caused ground-level ozone to spike to unhealthy levels across a broad area, including much of rural California as well as neighboring Nevada.

The study was published today in Geophysical Research Letters. It was funded by NASA and by the National Science Foundation, which sponsors NCAR.

"It's important to understand the health impacts of wildfires," says NCAR scientist Gabriele Pfister, the lead author. "Ozone can hit unhealthy levels even in places where people don't see smoke."

Although scientists have long known that wildfires can affect air quality by emitting particles and gases into the air, there has been little research to quantify the impacts. Fires worsen ozone levels by releasing nitrogen oxides and hydrocarbons, which can form ozone near the fire or far downwind as a result of chemical reactions in sunlight.

The researchers, using a combination of computer models and ground-level measurements, studied intense California wildfires that broke out in September and October of 2007. They found that ozone was three times more likely to violate safe levels when fire plumes blew into a region than when no plumes were present.

At the time of the wildfires, the public health standard for ozone set by the Environmental Protection Agency (EPA) was 0.08 parts per million over an eight-hour period. The EPA has since tightened the standard to 0.075 parts per million. Under the stricter standard, the number of violations would have nearly doubled.

While ozone in the stratosphere benefits life on Earth by blocking ultraviolet radiation from the Sun, ozone in the lower atmosphere can trigger a number of health problems. These range from coughing and throat irritation to more serious problems, such as aggravation of asthma, bronchitis, and emphysema. Ground-level ozone pollution also damages crops and other plants.

"Wildfires are expected to worsen in the future, especially as our climate grows warmer," Pfister says. "But we are only now beginning to understand their potential impacts on people and ecosystems, not only nearby but also potentially far downwind."

Rural impacts

The unhealthy levels of ozone the researchers detected occurred mostly in rural areas. This finding may be a result of the computer modeling, which lacked the fine detail to zoom in on relatively compact urban areas. However, the authors also speculate that wildfire emissions have a greater impact on ozone levels in the countryside than on cities. The reason has to do with chemistry. Cities tend to have more nitrogen dioxide, a pollutant that can, at high levels, reduce the efficiency with which ozone is produced or even destroy ozone.

"The impact of wildfires on ozone in suburban and rural areas, far from urban sources of pollution, was quite noticeable," says NCAR scientist Christine Wiedinmyer, a co-author of the paper.

The paper notes that ozone levels would likely have been even greater except that Santa Ana winds in October blew wildfire plumes over the Pacific Ocean, safely away from populated areas.

Tracking the emissions

To measure the impact of the fires on ozone formation, the researchers turned to a pair of computer models developed at NCAR. With the first one, a specialized fire model, they estimated the amount of vegetation burned and resulting emissions of nitrous oxides, sulfur dioxide, and other pollutants. Those results went into a global air chemistry model that simulated the movement of the emissions and evolving chemistry and tracked the resulting formation of ozone as the fire plumes spread downwind.

The scientists compared their modeling results with ozone measurements from a network of EPA ground stations at various sites in California. This enabled them to determine both the number of ozone violations and the extent to which the wildfires contributed to those violations. It also enabled them to verify the accuracy of the model.

The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation. Any opinions, findings and conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Gabriele Pfister, NCAR Scientist
303-497-2915
pfister@ucar.edu

David Hosansky | Newswise Science News
Further information:
http://www.ucar.edu

More articles from Earth Sciences:

nachricht How much does groundwater contribute to sea level rise?
03.05.2016 | International Institute for Applied Systems Analysis (IIASA)

nachricht Evidence points to widespread loss of ocean oxygen by 2030s
02.05.2016 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Erste Filmaufnahmen von Kernporen

Mithilfe eines extrem schnellen und präzisen Rasterkraftmikroskops haben Forscher der Universität Basel erstmals «lebendige» Kernporenkomplexe bei der Arbeit gefilmt. Kernporen sind molekulare Maschinen, die den Verkehr in und aus dem Zellkern kontrollieren. In ihrem kürzlich in «Nature Nanotechnology» publizierten Artikel erklären die Forscher, wie bewegliche «Tentakeln» in der Pore die Passage von unerwünschten Molekülen verhindern.

Das Rasterkraftmikroskop (AFM) ist kein Mikroskop zum Durchschauen. Es tastet wie ein Blinder mit seinen Fingern die Oberflächen mit einer extrem feinen Spitze...

Im Focus: Nuclear Pores Captured on Film

Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.

Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...

Im Focus: 2+1 ist nicht immer 3 - In der Mikro-Welt macht Einigkeit nicht immer stark

Wenn jemand ein liegengebliebenes Auto alleine schiebt, gibt es einen bestimmten Effekt. Wenn eine zweite Person hilft, ist das Ergebnis die Summe der Kräfte der beiden. Wenn zwei kleine Teilchen allerdings ein weiteres kleines Teilchen anschieben, ist der daraus resultierende Effekt nicht notwendigerweise die Summe ihrer Kräfte. Eine kürzlich in Nature Communications veröffentlichte Studie hat diesen merkwürdigen Effekt beschrieben, den Wissenschaftler als „Vielteilchen-Effekt“ bezeichnen.

 

Im Focus: 2+1 is Not Always 3 - In the microworld unity is not always strength

If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”

In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...

Im Focus: Winzige Mikroroboter, die Wasser reinigen können

Forscher des Max-Planck-Institutes Stuttgart haben winzige „Mikroroboter“ mit Eigenantrieb entwickelt, die Blei aus kontaminiertem Wasser entfernen oder organische Verschmutzungen abbauen können.

In Zusammenarbeit mit Kollegen in Barcelona und Singapur verwendete die Gruppe von Samuel Sánchez Graphenoxid zur Herstellung ihrer Motoren im Mikromaßstab. D

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

UFW-Fachtagung im Vorzeichen von Big Data und Industrie 4.0

03.05.2016 | Veranstaltungen

analytica conference 2016 in München - Foodomics, mehr als nur ein Modebegriff?

03.05.2016 | Veranstaltungen

Diabetes Kongress 2016: Diabetes schädigt das Herzkreislauf-System

02.05.2016 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Hepatitis C-Virus missbraucht den Fettstoffwechsel der Leber

03.05.2016 | Biowissenschaften Chemie

UFW-Fachtagung im Vorzeichen von Big Data und Industrie 4.0

03.05.2016 | Veranstaltungsnachrichten

Ein starkes Team: B2RUN und moove bringen Firmen in Bewegung

03.05.2016 | Unternehmensmeldung