Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New eyes in the sky

11.07.2012
UI researchers develop technique to help pollution forecasters see past clouds
Until now, scientists who study air pollution using satellite imagery have been limited by weather. Clouds, in particular, provide much less information than a sunny day.

University of Iowa scientists have created a technique to help satellites "see" through the clouds and better estimate the concentration of pollutants, such as soot. The finding is important, because, like GPS systems, clouds block remote-sensing satellites' ability to detect, and thus calculate, the concentration of pollution nearer to the ground. This includes particles (commonly known as soot) that reduce air quality and affect weather and climate.

The results of the study are published July 9 in the online early edition of the journal Proceedings of the National Academy of Sciences (PNAS).
This image shows two MODIS-Aqua products for Oct. 17, 2008, over the persistent Southeast Pacific stratocumulus deck, off the coasts of Chile and Peru. UI researchers and their colleagues have developed a new technique to evaluate how aerosol pollutants affect clouds, thereby giving scientists the ability to examine clouds and determine particle concentrations in the atmosphere below. Satellite retrievals courtesy of NASA Goddard Space Flight Center; image courtesy of Pablo Saide, Greg Carmichael, Scott Spak, Matthew Janechek, and Nicholas Thornburg, University of Iowa.

“Particles in the atmosphere (aerosols) interact with clouds changing their properties. With this technique, we can use remote sensing observations from satellites to estimate these cloud properties in order to correct predictions of particle concentrations. This is possible due to a numerical model that describes these aerosol-clouds interactions,” says Pablo Saide, environmental engineering doctoral student and researcher at the UI Center for Global and Regional Research (CGRER).

Scott Spak, co-author and assistant professor of civil and environmental engineering in the UI College of Engineering, adds that the new technique is expected to find immediate application across a wide range of activities. Examples include air quality forecasting, numerical weather prediction, climate projections, oceanic and anthropogenic emissions estimation, and health effects studies.

But the ability to see pollution “through the clouds” is also expected to have “on the ground” health results.

“Unlike previous methods, this technique can directly improve predictions of near-surface, fine-mode aerosols—such as coal-fired electric generating plants and wood-fueled cooking fires—responsible for human health impacts and low-cloud radiative forcing (solar heating),” says Greg Carmichael, co-author, professor of chemical and biochemical engineering, and CGRER co-director. "This technique is also complementary to previous methods used, allowing the observing system to ‘see aerosols’ even under cloudy conditions.”

Here’s how the technique works:
•Existing weather satellites observe warm, single-layer clouds, such as the stratocumulus clouds that form off the west coasts of Africa, North America, and South America. These clouds are thought to be the main factors contributing to climate cooling.

•Researchers calculate the number of droplets in the clouds using the satellite data, which are compared to a model estimate provided by the UI program.

•As airborne particles interact with clouds changing their properties, model estimates of particles are corrected so that the model will generate a better agreement with the satellite number of droplets.

•Particles interacting with clouds are usually below clouds, thus, in some cases, the model corrections can be attributed to manmade emissions.

The researchers conducted their study using National Science Foundation (NSF) aircraft measurements to make simultaneous cloud and particle observations, which verified satellite observations and the mathematical formulas used to determine the pollution concentrations in the air.

All three UI researchers agree that their new technique for seeing through clouds to make ground observations is likely to generate growing interest as the need to infer ground air pollution levels, and the need to mitigate the human hazards posed, grows larger.

In addition to UI researchers, paper co-authors include Patrick Minnis of NASA Langley Research Center, Hampton, Va., and Kirk Ayers of Science Systems and Applications Inc., Hampton, Va.

The PNAS article is titled “Improving aerosol distributions below clouds by assimilating satellite-retrieved cloud droplet number.”

The research was funded by NSF and NASA.
Contacts
Gary Galuzzo, University Communication and Marketing, 319-384-0009

Gary Galluzzo | EurekAlert!
Further information:
http://www.uiowa.edu

Further reports about: GPS system NASA NSF PNAS Science TV Spak environmental engineering

More articles from Earth Sciences:

nachricht Better model of water under extreme conditions could aid understanding of Earth's mantle
21.06.2018 | University of Chicago

nachricht The Janus head of the South Asian monsoon
21.06.2018 | Max-Planck-Institut für Chemie

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Better model of water under extreme conditions could aid understanding of Earth's mantle

21.06.2018 | Earth Sciences

What are the effects of coral reef marine protected areas?

21.06.2018 | Life Sciences

The Janus head of the South Asian monsoon

21.06.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>