Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Amount of dust blown across the West is increasing, says CU-Boulder study

11.06.2013
The amount of dust being blown across the landscape has increased over the last 17 years in large swaths of the West, according to a new study led by the University of Colorado Boulder.

The escalation in dust emissions — which may be due to the interplay of several factors, including increased windstorm frequency, drought cycles and changing land-use patterns — has implications both for the areas where the dust is first picked up by the winds and for the places where the dust is put back down.


This image shows a dust storm in Canyonlands National Park.

Credit: Jason Neff

"Dust storms cause a large-scale reorganization of nutrients on the surface of the Earth," said Janice Brahney, who led the study as a CU-Boulder doctoral student. "And we don't routinely monitor dust in most places, which means we don't have a good handle on how the material is moving, when it's moving and where it's going."

Based on anecdotal evidence, such as incidents of dust coating the snowpack in the southern Rockies and a seemingly greater number of dust storms noticed by Western residents, scientists have suspected that dust emissions were increasing. But because dust has not been routinely measured over long periods of time, it was difficult to say for sure.

"What we know is that there are a lot of dust storms, and if you ask people on the Western Slope of Colorado, or in Utah or Arizona, you'll often hear them say, 'Yeah, I grew up in this area, and I don't remember it ever being like this before,'" said CU-Boulder geological sciences Associate Professor Jason Neff, Brahney's adviser and a co-author of the paper. "So there is anecdotal evidence out there that things are changing, but no scientific data that can tell us whether or not that's true, at least for the recent past."

For the new study, recently published online in the journal Aeolian Research, the research team set out to determine if they could use calcium deposition as a proxy for dust measurements. Calcium can make its way into the atmosphere — before falling back to earth along with precipitation — through a number of avenues, including coal-fired power plants, forest fires, ocean spray and, key to this study, wind erosion of soils.

The amount of calcium dissolved in precipitation has long been measured by the National Atmospheric Deposition Program, or NADP, which first began recording the chemicals dissolved in precipitation in the late 1970s to better understand the phenomena of acid rain.

Brahney and her colleagues reviewed calcium deposition data from 175 NADP sites across the United States between 1994 and 2010, and they found that calcium deposition had increased at 116 of them. The sites with the greatest increases were clustered in the Northwest, the Midwest and the Intermountain West, with Colorado, Wyoming and Utah seeing especially large increases.

The scientists were able to determine that the increase was linked to dust erosion because none of the other possible sources of atmospheric calcium — including industrial emissions, forest fires or ocean spray — had increased during the 17-year period studied.

It's also likely that the calcium deposition record underrepresents the amount of dust that's being blown around, said Brahney, who is now a postdoctoral researcher at the University of British Columbia in Canada. That's because the NADP network only measures dust that has collided with water in the atmosphere before precipitating to earth — not dust that is simply moved by the wind. And not all dust contains the same amount of calcium.

The increase in dust erosion matters, the researchers said, because it can impoverish the soil in the areas where dust is being lost. Wind tends to pick up the finer particles in the soils, and those are the same particles that have the most nutrients and can hold onto the most soil moisture, Brahney said.

Increasing amounts of dust in the atmosphere also can cause people living in the rural West a variety of problems, including poor air quality and low visibility. In extreme cases, dust storms have shut down freeways, creating problems for travelers.

The areas where the dust travels to are also affected, though the impacts are more mixed. When dust is blown onto an existing snowpack, as is often the case in the Rockies, the dark particles better absorb the sun's energy and cause the snowpack to melt more quickly. But the dust that's blown in also brings nutrients to alpine areas, and the calcium in dust can buffer the effects of acid rain.

In the future, researchers working in Neff's lab hope to get a more precise picture of dust movement by measuring the dust itself. In the last five years, large vacuum-like measuring instruments designed specifically to suck in dust emissions have been installed at sites between the canyon lands of Utah and the Front Range of the Rockies. Once scientists have enough data collected, they'll be able to look for trends in dust emissions without relying on proxies.

The study was funded by the National Science Foundation.

Jason Neff | EurekAlert!
Further information:
http://www.colorado.edu

More articles from Earth Sciences:

nachricht The unintended consequences of dams and reservoirs
14.11.2018 | Uppsala University

nachricht Earth's magnetic field measured using artificial stars at 90 kilometers altitude
14.11.2018 | Johannes Gutenberg-Universität Mainz

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Epoxy compound gets a graphene bump

14.11.2018 | Materials Sciences

Microgel powder fights infection and helps wounds heal

14.11.2018 | Health and Medicine

How algae and carbon fibers could sustainably reduce the athmospheric carbon dioxide concentration

14.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>