Lockdowns last year in response to COVID-19 resulted in drastic cuts to emissions, especially from vehicle tailpipes, and yet some urban areas saw a paradoxical spike in ozone air pollution. A new study led by the National Center for Atmospheric Research (NCAR) used a sophisticated computer model to disentangle the complicated web of atmospheric chemistry and meteorology to determine the causes of poor air quality.
ACOM Scientists presented their research online at the annual meeting of the American Meteorological Society during 10-15 January 2021. All oral and poster sessions, panel discussions, exhibits, and some networking for the 101st Annual Meeting were held this year in a virtual format.
With the unprecedented global reduction in economic activities following the COVID-19 pandemic outbreak in early 2020, most emissions of air pollutants have decreased substantially throughout the first half of the year. This unintended global experiment has given insight on some of the processes that control air quality and offered a glimpse into a potential future in which air quality would be improved. Read more at ACOM Research Highlights . . .
ACOM researchers presented talks and posters at the AGU 2020 fall meeting, held online this year due to Covid-19. The schedule below shows the web location and time of each scheduled presentation. All dates and times are in Pacific Standard Time (PST = UTC-08:00).
Wildfires burning in the West affect not only the areas burned, but also the wider regions covered by smoke. As hazy skies and hazardous air quality become regular features of late summer weather, scientists are working to better understand the plumes.
Read more at NCAR & UCAR News (November 4, 2020) . . .
ACOM scientist Sara Martinez-Alonso delivered an online lecture about remote sensing to the Atmospheric and Environmental Chemistry Seminar at Harvard University in Boston, Massachusetts on October 9, 2020. Her recorded presentation is available for viewing at the ACOM YouTube channel, with permission from Harvard University.
ACOM scientists Rebecca Hornbrook and Rebecca Buchholz contributed to a Wired article about wildfire smoke:
Janyl Madykova is from Kyrgyzstan and came to the USA in 2018 as a Fulbright Scholar. In summer 2020 she virtually visited NCAR under a Muskie Internship Program collaborating with ACOM on exploring air quality in Central Asia. Air pollution is a major societal and environmental threat that is occurring in many places across the world, yet the Central Asian region is significantly understudied. Read more at ACOM Research Highlights . . .
Smoke from several wildfires has been hazing up the Front Range, along with the usual summer ozone. ACOM Scientist Gabriele Pfister studies air quality for the National Center for Atmospheric Research and says both the smoke particles and the ozone have short term and long-term health impacts, mainly to the respiratory system.
Three months of less driving won’t fix Colorado’s air quality woes. ACOM scientist Frank Flocke knew air pollution was increasing at the end of May [2020] just by listening. He could hear a growing number of cars speeding down the busy Foothills Parkway from his home office in Boulder.
“We have seen a decrease in air pollution on short time frames,” says atmospheric scientist Helen Worden of the National Center for Atmospheric Research in Boulder, Colorado. In one unpublished result since the pandemic began, Worden and colleagues found that, in a corridor between Wuhan and Beijing, peak values of CO were down by 30–45% following Chinese New Year this year compared with the same period in 2019.
ACOM Deputy Director Gabi Pfister spoke with Jamie Yuccas about blue skies and clean air in Los Angeles during the coronavirus lockdown. If all passenger cars were to be taken off the road, what would happen to our air quality? The COVID-19 health crisis has shown us that there are ways we can make significant change in the human footprint on our atmosphere and on nature. Gabi's segment begins at time 3:00.
The COVID-19 health crisis is obviously a terrible situation, with more than 34,000 deaths worldwide as of March 30, 2020. And experts say that the real impact to climate change is what we take away from the pandemic—the choices we make in our recovery. It does, however, provide scientists some insight as to what happens to our atmosphere when our lifestyles and economy undergo major change. “It’s an unwanted atmospheric experiment,” says Helen Worden, an atmospheric scientist at the National Center for Atmospheric Research (NCAR).
NCAR/ACOM scientist Rebecca Buchholz contributed to a broadcast discussion of how wildfires affect weather and climate. The Carr Fire in Northern California during July-August 2018 reduced air quality across the western United States. In this broadcast, the question is posed at minute 24:00, and Rebecca's response is minutes 28:00-33:00. Listen...
The discovery of a novel sulfur compound during a 2017 NASA airborne research campaign will likely spur a scientific reassessment of a fundamental marine chemical cycle which drives the formation of oceanic clouds that play a key role in moderating climate, scientists said. The chemical, dubbed hydroperoxymethyl thioformate (or HPMTF), was discovered by NOAA scientist Patrick Veres while monitoring air samples being analyzed by a new NOAA Chemical Ionization Mass Spectrometer on board NASA’s instrumented DC-8 flying laboratory.
ACOM Project Scientist Rebecca Buchholz talks with Connecticut Public Radio about how climate change is shaping wildfire patterns around the globe. Are severe natural disasters becoming the “new normal”? Walter Jetz, Professor of Ecology and Evolutionary Biology at Yale University, talks about the fires’ impact on biodiversity. Read more at WNPR.org . . .
ACOM scientist Rebecca Buchholz contributed to an audio story about the Australian bush fires, aired January 10, 2020 on National Public Radio. Wildfires release a lot of carbon when they burn vegetation, and that massive carbon release can potentially affect the climate. Rebecca recently visited family in Australia on a smoke-filled and subdued holiday.
NCAR/ACOM is now generating high-resolution, experimental, 48-hour forecasts of air pollutants across the contiguous United States. The predictions, which are freely available online, can help decision makers anticipate episodes of unhealthy air as well as accelerate research into the factors that influence air quality. Read more at UCAR AtmosNews . . .
As the Amazon burns at a rate higher than any year measured since 2010, the environmental crisis is being watched closely by researchers in Boulder, who have devoted years of study to the long-term implications of degradation to the planet’s forests, critical for their capacity to store carbon dioxide. Read more at Daily Camera . . .
The phenomenon, called a pyrocumulonimbus or PyroCb, “is essentially a thunderstorm that is created or driven by a wildfire,” said David Peterson (Naval Research Laboratory). “As we fly into this deep smoke, the light goes down, and the sun gets orange,” observed Rebecca Hornbrook, an atmospheric chemist at the National Center for Atmospheric Research (ACOM Laboratory).
Sparked by a listener question, CPR Colorado Matters interviewed ACOM Scientist Gabriele Pfister about the transport of ozone pollution from the Colorado Front Range to the mountains. Pfister has been tracking the movement of polluted ground-level ozone for years with the Boulder-based National Center for Atmospheric Research. And yes, it makes it to the mountains.
ACOM scientist Xuan Zhang recently led a major community project in the NCAR Atmospheric Simulation Chamber.
Tuscon.com reported on the correlation between rising temperatures and higher ozone levels in Arizona and interviewed ACOM scientist Gabi Pfister on her 2014 study on expected changes in air quality in the U.S. by mid-century due to climate change.
Forrest Lacey, ASP Postdoc in ACOM, has been interviewed by Channel 9news about the outcomes of the recent American Lung "State of the Air" 2019 report and the health effects of exposure to ozone, short term particulates, and long term particulate, specifically as they relate to the Denver Area.
KGNU Morning Magazine has interviewed ACOM Scientist Gabriele Pfister on the air quality in the Colorado Front Range and the relative contributions from local versus transported pollution. This discussion was sparked by recent news that Colorado Governor Jared Polis and the Department of Public Health and Environment’s (CDPHE) Air Quality Control Commission rejected a push by a pro-industry group to pursue an “international contributions” exemption that would reduce the state’s responsibility under the federal Clean Air Act.
Monday, March 4, 2019: Siyuan Wang of ASP-NCAR presented an ACOM Seminar: Halogen chemistry in the Arctic boundary layer: new chemical insights Location: FL2-1022 (large seminar room), NCAR Foothills Laboratory; 3:15 pm - refreshments, 3:30 pm - seminar. The recorded video is available on the ACOM YouTube Channel.
ACOM staff joined other AMS members at the annual meeting of the American Meteorological Society in Phoenix, Arizona during 6–10 January, 2019. Although the partial government shutdown prevented some Federal employees from attending the meeting, ACOM scientists from UCAR still presented talks and posters during the week:
Several ACOM staff were at University of California-Davis during 5-7 December 2018 to attend the Atmospheric Chemical Mechanisms Conference 2018 including Louisa Emmons, Sasha Madronich, Camille Mouchel
Mashable.com interviewed ACOM Deputy Director Gabriele Pfister on the topic of wildfires and air quality. “We’re right in the middle of climate change,” Gabi remarked, referring to the increased frequency of record-breaking heat as average temperatures continue to climb. Wildfires flare up during daytime and in a hotter climate. Government-issued warnings about unhealthy air quality will come more frequently even in communities far from those burning forests.
Scientific American reported on ACOM scientist Simone Tilmes' experiments with geoengineering. The eruption of Mt. Pinatubo in June 1991 demonstrated that sulfur aerosols have a cooling effect by shading the earth's surface.
There will be an additional plane in the air over wildfires in the northwestern United States in coming weeks, but it won't be there trying to put them out. The C-130 research aircraft flying to Boise, Idaho, from the Rocky Mountain Metropolitan Airport in Broomfield on Friday will be taking to the skies over those blazes to foster a better understanding of their impact on air quality, weather patterns and longer-term climate change.
ACOM scientists Samuel Hall, Lizzy Asher, Kirk Ullman, Eric Apel, Alan Hills, and Becky Hornbrook are currently taking part in the ATom-4 Field Campaign.
ACOM scientist Simone Tilmes was quoted in Live Science about a proposal to use salt in the upper troposphere to increase the atmosphere's reflectivity and thereby cool the earth. Unlike some other aerosols, sodium chloride (table salt) is not harmful to the earth's ozone layer. Tilmes cautions that salt often includes reactive iodine, an element that could also play a role in atmospheric chemistry.
April 6, 2018
The planet's ozone layer may be thinning over earth’s heavily populated areas. Robert Lee Hotz at the Wall Street Journal reports, "In a new analysis, scientists detect shrinking of the planet’s protective shield at lower levels of the stratosphere over Earth’s nonpolar regions. Part of Earth’s protective ozone shield may be thinning over the most heavily populated regions of the globe, even as an ozone hole over Antarctica continues to mend".
In a surprising study, scientists say everyday chemicals now rival cars as a source of air pollution. Chris Mooney at The Washington Post reports that "the nature of air pollution is changing dramatically as cars become cleaner — leaving personal-care products, paints, indoor cleaners and other chemical-containing agents as an increasingly dominant source of key emissions." As emissions from the transportation sector decrease, the gases emitted by household products and activities have become more significant.
A new NASA-led study has solved a puzzle involving the recent rise in atmospheric methane, a potent greenhouse gas, with a new calculation of emissions from global fires. The new study resolves what looked like irreconcilable differences in explanations for the increase.
A comprehensive new air quality report for the state of Colorado quantifies the sources of summertime ozone in Denver and the northern Front Range, revealing the extent to which motor vehicles and oil and gas operations are the two largest local contributors to the pollutant.
One of the largely unanticipated impacts of a changing climate may be a decline in sunlight's ability to disinfect lakes, rivers, and coastal waters, possibly leading to an increase in waterborne pathogens and the diseases they can cause in humans and wildlife. ACOM's TUV Model was used in the study to evaluate the disinfecting power of UV light.
Tremendous amounts of soot, lofted into the air from global wildfires following a massive asteroid strike 66 million years ago, would have plunged Earth into darkness for nearly two years, new research finds. This would have shut down photosynthesis, drastically cooled the planet, and contributed to the mass extinction that marked the end of the age of dinosaurs.
CASPER MOUNTAIN. — It’s nothing like a sunset. It’s cold and dark, but it’s not like nighttime, or even twilight. The moon just snaps into place over the last slivers of the sun, turning the sun into a dark hole. The only illumination — a flat, ghostly, metallic sort of light — is from peaked gossamer streamers stretching out toward the edges of the sky.
Measurements of carbon dioxide from the MOPITT satellite instrument have been validated using the NDACC network of ground-based measurements. ACOM scientist Rebecca Buchholz and colleagues reported on their study of MOPITT version 6 retrievals using total column CO measurements from ground-based remote-sensing Fourier transform infrared spectrometers (FTSs).
Wildfires tend to be more intense and hence costly and are predicted to increase in frequency under a warming climate. For example, the recent August 2015 Washington State fires were the largest in the state’s history. Such large fires impact not only the local environment but also affect air quality far downwind through the long-range transport of pollutants. Global to continental scale coverage showing the evolution of CO resulting from fire emission is available from satellite observations.
About half of atmospheric carbon monoxide (CO) is from direct (CO) emissions that are due to incomplete combustion and are related to both natural (e.g. wildfires) and anthropogenic activities. The remainder of CO in the atmosphere is produced from the chemical oxidation of hydrocarbons, mainly from biogenic sources and methane (CH4). Since most of the hydrocarbons, CO, and CH4 in the atmosphere are oxidized by the hydroxyl radical (OH), the associated chemical lifetimes of these species are strongly coupled with OH.
In celebration of Air Quality Awareness week, NCAR is hosting an open house featuring information and family friendly activities about air quality. Learn from experts about air quality, how we measure and research it, and how it impacts humans, plants, and animals. NCAR’s new air quality exhibit will also be featured.
With world leaders agreeing to try to limit the increase in global temperatures, scientists at the National Center for Atmospheric Research (NCAR) are taking a look at whether geoengineering the climate could counter enough warming to help meet that goal. "One thing that surprised me about this study is how much geoengineering it would take to stay within 2 degrees if we don't start reducing greenhouse gases soon," said ACOM scientist Simone Tilmes, the lead author.
ACOM scientist Christine Wiedinmyer is a co-author of a new study into the health effects of the 2015 Indonesian wildfires. This is an excerpt from a news release issued by Newcastle University.
Wildfires in Indonesia and Borneo exposed 69 million people to unhealthy air pollution, new research has shown.
Susan Solomon at MIT, along with ACOM scientists Doug Kinnison and Michael Mills, have identified the “first fingerprints of healing” of the Antarctic ozone layer, published on June 30, 2016 in the journal Science. The research was covered by BBC Science.
Between May 1 and June 12, 2016, ACOM scientists and their colleagues from NASA, U.S. and South Korean universities, and South Korea’s National Institute of Environmental Research (NIER) will collect observations from airborne labs, ships, satellites, and ground-based instruments. The campaign, which involves more than 580 researchers from 72 institutions, is called KORUS-AQ (Korea U.S.-Air Quality study).
Australian fires in 2019 and 2020 injected almost 1 million metric tons of smoke into the stratosphere, causing it to warm and likely contributing to a large and persistent ozone hole.
Lockdowns last year in response to COVID-19 resulted in drastic cuts to emissions, especially from vehicle tailpipes, and yet some urban areas saw a paradoxical spike in ozone air pollution.
Ozone in the lower atmosphere fell by 7% on average across the Northern Hemisphere, new research finds.
The lockdowns and reduced societal activity related to the COVID-19 pandemic affected emissions of pollutants in ways that slightly warmed the planet for several months last year, according to new research led by NCAR.
Pieternel Levelt has been selected to lead the Atmospheric Chemistry Observations & Modeling Laboratory (ACOM) at the National Center for Atmospheric Research (NCAR). Levelt currently serves as the head of the R&D Satellite Observations department at The Royal Netherlands Meteorological Institute while also serving as a professor at Delft University of Technology.
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