Posted on February 28, 2014 by Bob Berwyn
What’s the role of coniferous trees in regulating climate?
Fast growth of particles from pine tree fumes surprises researchers
By Summit Voice
FRISCO — Forests may play a much bigger role in global climate than previously believed. In addition to cycling carbon, it appears that gases wafting from conifers quickly form small particles that can reflect sunlight and promote cloud formation, according to a new study that looked at forest aerosols at the molecular level.
“In many forested regions, you can go and observe particles apparently form from thin air. They’re not emitted from anything, they just appear,” said Joel Thornton, a University of Washington associate professor of atmospheric sciences. Continue reading
Filed under: climate and weather, Environment, forests | Tagged: aerosols, atmospheric science, climate, forests, global warming | 1 Comment »
Posted on November 27, 2013 by Bob Berwyn
Air pollution can be a big factor in development of thunderclouds
Air pollution can have a significant impact on the development of thunderclouds, causing cloud remnants to persist longer. bberwyn photo.
FRISCO — Air pollution can have a significant effect on the development of thunderhead clouds, causing the cloud remnants to persist high in the atmosphere long after thunderstorms dissipate. This, in turn, can affect daily temperature ranges, as the lingering clouds partially cool the Earth during the day with their shadows, but trap heat to keep nighttime temperatures warmer.
The new study, from the Department of Energy’s Pacific Northwest National Laboratory, helps answer long-running questions about how airborne pollutants affect climate warming. The findings will help provide a gauge for the accuracy of weather and climate models.
“This study reconciles what we see in real life to what computer models show us,” said atmospheric scientist Jiwen Fan. “Observations consistently show taller and bigger anvil-shaped clouds in storm systems with pollution, but the models don’t always show stronger convection. Now we know why.” Continue reading
Filed under: climate and weather, Environment | Tagged: aerosols, air pollution, atmospheric science, cloud formation, Environment | 1 Comment »
Posted on November 7, 2013 by Bob Berwyn
New study suggests natural aerosols may be a bigger factor than previously thought
By Summit Voice
FRISCO — In their quest to better understand the role of aerosols in the Earth’s climate, researchers may have to try and find the cleanest parts of the atmosphere.
Knowing to what degree both human-caused and natural aerosols mask the effects of heat-trapping greenhouse gases is crucial to making accurate climate predictions, according to a new study that assessed 28 factors that could affect the uncertainties in cloud brightness.
Natural aerosols, such as emissions from volcanoes or plants, may contribute more uncertainty than previously thought to estimates of how the climate might respond to greenhouse gas emissions. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: aerosols, atmospheric science, climate change, global warming, Greenhouse gas | Leave a comment »
Posted on May 25, 2013 by Bob Berwyn
New satellite data shows volcanoes are a bigger factor than industrial emissions, at least high in the atmosphere
Alaska’s Redoubt Volcano erupting in 1990. Photo courtesy USGS/R.J. Clucas.
By Summit Voice
FRISCO — Scientists have long known that aerosols can have a major effect on climate, and with measurements from sensitive satellite-based instruments, they’re getting a better handle on the formation, distribution and sources of various sulfur compounds in the atmosphere.
In a new study, researchers with the Karslruhe Institute of Technology say they’ve compiled one of the most comprehensive overview of sulfur dioxide measurements.
“Sulfur compounds up to 30 km altitude may have a cooling effect,” said KIT researcher Michael Höpfner, explaining that sulfur dioxide and water vapor react to sulfuric acid that forms aerosols, that reflect solar radiation back into universe. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: aerosols, climate, Envisat, global warming, sulfur dioxide, volcanoes | 1 Comment »
Posted on November 5, 2012 by Bob Berwyn
NASA research adds to understanding of dust events
NASA often captures images of dust storms from orbiting satellites, but one recent study looked at the dust from the ground up, finding that the events can have localized warming effect.
By Summit Voice
SUMMIT COUNTY — Desert dust storms blowing across the Colorado Rockies from the Southwest have already been implicated as a factor in earlier snowmelt; now, new research by NASA suggests that airborne dust can have a significant, localized effect on atmpospheric temperatures.
The study was conducted in a semi-arid region between China’s Taklimakan and Gobi deserts, where the NASA team set up a field research site in Zhangye. Using an array of upward-looking instruments for measuring airborne dust particles, they assessed the impact of dust storms from the adjacent deserts. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: aerosols, climate, dust storms, Earth, global warming, NASA | Leave a comment »
Posted on September 25, 2012 by Bob Berwyn
Asian dust arriving over North America in significant quantities
Dust from Asia is a big factor in the atmosphere over North America. Map courtesy NASA.
By Summit Voice
SUMMIT COUNTY — The desert Southwest isn’t the only source of dust in the atmosphere over Colorado. As much as 64 million tons of dust from minerals, soils, pollutants and other sources cross the ocean from Asia, carried by prevailing west winds, and mix into over North America each year, according to a NASA study published last spring.
That’s just about about equal to the 69 million tons of aerosols produced domestically by natural processes, transportation, and industrial sources. The tiny particles can affect the climate, as well human health if they mix down into the lower atmosphere.
Dust movement is particularly active in spring, when the rise of cyclones and strong mid-latitude westerlies boost particle transport across the Pacific. In addition to the transport from Asia, North America also imports aerosols from Africa and the Middle East.
“This is a crucial step toward better understanding how these tiny but abundant materials move around the planet and impact climate change and air quality,” said Hongbin Yu, lead author and an atmospheric scientist at the University of Maryland and NASA’s Goddard Space Flight Center. Observing aerosols and quantifying their impact on warming or cooling the planet remains one of the most difficult challenges in climate science. Continue reading
Filed under: Colorado, Snow and weather | Tagged: aerosols, climate, Colorado, dust on snow, NASA | Leave a comment »
Posted on July 8, 2012 by Bob Berwyn
A NASA satellite captures a view of the smoke billowing from the Nabro Volcano in Ethiopia during a June 2011 eruption.
New study to help inform climate models
By Summit Voice
SUMMIT COUNTY — Using data from sensitive satellite instruments, researchers at the University of Saskatchewan have determined relatively small volcanic eruptions can affect climate on a global level, as aerosols from the eruptions are transported into the upper levels of the atmosphere by weather systems like monsoons.
“If an aerosol is in the lower atmosphere, it’s affected by the weather and it precipitates back down right away,” said Adam Bourass, with university of Saskatchewan’s Institute of Space and Atmospheric Studies. “Once it reaches the stratosphere, it can persist for years, and with that kind of a sustained lifetime, it can really have a lasting effect,” Bourass said, explaining that the particles scatter incoming sunlight, thus cooling the Earth’s surface. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: aerosols, Atmosphere, Atmospheric Research, Mount Pinatubo, Rutgers University, University of Saskatchewan, volcanoes | Leave a comment »
Posted on November 14, 2011 by Bob Berwyn
A 2006 image from NASA's Terra satellite shows haze over the East Coast of the U.S.
Aerosols affect cloud formation, height and thickness; changing precipitation frequency and intensity
By Summit Voice
SUMMIT COUNTY — Shortly after another recent study found that pollution may be intensifying hurricanes in the Arabian Gulf, University of Maryland scientists said increases in air pollution can intensify droughts and precipitation.
The research provides the first clear evidence of how aerosols, like soot, dust and other small particles in the atmosphere can affect weather and climate. The findings have important economic and water resource implications for regions across the United States and around the world, said the researchers and other scientists.
“Using a 10-year dataset of extensive atmosphere measurements from the U.S. Southern Great Plains research facility in Oklahoma (run by the Department of Energy’s Atmospheric Radiation Measurement program), we have uncovered, for the first time, the long-term, net impact of aerosols on cloud height and thickness, and the resultant changes in precipitation frequency and intensity,” says Zhanqing Li, a professor of atmospheric and oceanic science at Maryland and lead author of the study. Continue reading
Filed under: air quality, climate and weather, Colorado, Environment, Summit County news | Tagged: aerosols, air pollution, air quaility, Atmospheric Radiation Measurement, climate, Environment, weather | 2 Comments »
Posted on November 5, 2011 by Bob Berwyn
Cyclone Phet over Oman, June 4, 2010.
Buildup of aerosols weakens upper-level winds that normally shear tropical storms
By Summit Voice
SUMMIT COUNTY — A buildup of atmospheric pollutants may be contributing to the intensification of tropical cyclones in the Arabian Sea, said a group of researchers who documented a shift in upper-air wind patterns over the region.
The scientists linked those changes to increased aerosols, possibly originating over the Indian subcontinent. A widespread brown cloud dampens the formation of monsoon-related shearing winds that historically have weakened cyclones in the region.
“We are showing that pollution from human activity – as simple as burning wood or driving a vehicle with a diesel engine – can actually change these massive atmospheric phenomena in a significant way,” said the study’s lead author, Amato Evan, an environmental scientist in the University of Virginia’s College of Arts & Sciences. “It underscores the importance of getting a handle on emissions in the region.” Continue reading
Filed under: climate and weather, Hurricanes | Tagged: aerosols, climate, Gulf of Arabia, Tropical cyclones, Tropical Storm Phet, weather | Leave a comment »