Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rising air pollution worsens drought and flooding

03.01.2012
Study by Hebrew University and U. Of Maryland researchers shows

Increases in air pollution and other particulate matter in the atmosphere can strongly affect cloud development in ways that reduce precipitation in cool and relatively dry regions, such as Israel in winter, but also can increase rain and the intensity of severe storms in warm and moist regions or seasons, such as the eastern half of the US during summer, says a new study by researchers from the Hebrew University of Jerusalem and the University of Maryland.

The research provides clear evidence of how aerosols -- soot, dust and other small particles in the atmosphere -- can affect weather and climate. The findings have important implications for the availability, management and use of water resources in regions not only in Israel but around the world, say the researchers.

Using a 10-year dataset of extensive atmosphere measurements from the U.S. Southern Great Plains research facility in Oklahoma (run by the US Department of Energy’s Atmospheric Radiation Measurement program), the researchers 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.

This study confirmed and showed the importance of the theory developed by Prof. Daniel Rosenfeld of the Hebrew University of Jerusalem in his previous studies. The authors of the new study, who published it, along with Prof. Rosenfeld, are Prof. Zhanqing Li and Feng Niu and Yanni Ding of the University of Maryland; Jiwen Fan of Pacific Northwest National Laboratory; and Yangang Liu of Brookhaven National Laboratory, Upton, NY, The article appeared in a recent issue of Nature Geoscience.

The findings have significant policy implications for sustainable development and water resources, especially for those developing regions susceptible to extreme events, such as drought and flood. Increases in manufacturing, building of power plants and other industrial developments, together with urbanization, are often accompanied with increases in pollution whose adverse impacts on weather and climate, as revealed in this study, can undercut economic gains, it was stressed.

The aerosols, tiny solid or liquid particles suspended in air, include soot, dust and sulfate particles and are what we commonly think of when we talk about air pollution. Aerosols come, for example, from the combustion of fossil fuels, industrial and agricultural processes, and the accidental or deliberate burning of fields and forests. They can be hazardous to both human health and the environment.

Aerosols also affect cloud microphysics because they serve as nuclei around which water droplets or ice particles form. Both processes can affect cloud properties and rainfall. Different processes may work in harmony or offset each other, leading to a complex yet inconclusive interpretation of their long-term net effect.

“When the air rises, the water vapor condenses on aerosol particles to form cloud drops. In cleaner air the cloud drops are larger due to fewer drops and have better chances of colliding to form large rain drops. In polluted air, more and smaller drops are formed. They float in the air and are slow to coalesce into rain drops,” says Prof. Rosenfeld.

“With a small amount of moisture, most cloud drops never become large enough for efficient precipitation, and hence rainfall is reduced. The rain that is withheld in moist, polluted, deep clouds freezes at higher altitudes to form ice crystals or even hail. The energy released by freezing fuels the clouds to grow taller and create larger ice particles that produce more intense precipitation. This explains why air pollution can exacerbate both drought and flood,” says Rosenfeld.

This may partially explain Rosenfeld’s finding in another study that there are more severe convective storms during summer on weekdays compared to weekends in the eastern United State, because more pollution is emitted during the working weekdays than during the weekend.

Support for this latest research was provided by the Department of Energy, NASA, the National Science Foundation and the Chinese Ministry of Science and Technology.

(Photo of Prof. Rosenfeld available via e-mail upon request)

For further information: Jerry Barach, Dept. of Media Relations, the Hebrew University,
Tel: 02-588-2904.
Orit Sulitzeanu, Hebrew University spokesperson, Tel: 054-8820016

Jerry Barach | The Hebrew University of Jerusal
Further information:
http://www.huji.ac.il

More articles from Studies and Analyses:

nachricht Antarctic Ice Sheet mass loss has increased
14.06.2018 | Technische Universität Dresden

nachricht WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

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

Scientists predict a new superhard material with unique properties

18.06.2018 | Materials Sciences

Squeezing light at the nanoscale

18.06.2018 | Physics and Astronomy

A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive

15.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>