Jul 27, 2012
Technique developed to see pollutants through cloud formationsBack
Engineering|Africa|CoAL|Paper|System|Systems|Africa|North America|South America|UI College|University Of Iowa|Chemical And Biochemical Engineering|Coal-fired Electricity Generating Plants|Systems|Africa|North America|South America|Environmental|Greg Carmichael|Kirk Ayers|Pablo Saide|Patrick Minnis|Scott Spak|Iowa|Environmental Engineering|Remote Sensing
© Reuse this
Asatellite technique to better estimate con- centrations of pollutants, such as soot, through cloud cover has been developed by University of Iowa (UI) scientists, the university said in a statement.
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), which reduce the air quality and affect the weather as well as the climate.
UI researchers have developed a new technique to evaluate how aerosol pollutants affect clouds, enabling scientists to examine clouds to determine particle concentrations in the atmosphere below.
“Particles in the atmosphere (aerosols) interact with clouds, changing their properties. With this technique, we can use remote sensing observations from satellites to estimate cloud properties in order to correct predictions of particle concentrations. This is possible, owing to a numerical model that describes these aerosol-cloud interactions,” said UI Center for Global and Regional Research (CGRER) environmental engineering doctoral student and researcher Pablo Saide.
The new technique is expected to find imme- diate application across a range of activities. Examples include air-quality forecasting, numerical weather prediction, climate projections, oceanic and anthropogenic emissions estimations, as well as health-effect studies, added UI College of Engineering co-author and assistant professor of civil and environmental engineering Scott Spak.
“Unlike previous methods, this technique can directly improve predictions of near- surface, fine-mode aerosols, such as coal-fired electricity generating plants and wood-fuelled cooking fires, responsible for human health impacts and low-cloud radiative forcing (solar heating),” said UI CGRER codirector, professor of chemical and biochemical engineering and co-author Greg Carmichael.
“This technique is also complementary to previous methods used, enabling the observing system to ‘see’ aerosols even under cloudy conditions,” he explained.
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 then compared to a model estimate provided by the UI programme.
As airborne particles interact with clouds, the model estimates of particles are corrected so that the model generates a better correlation 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 emissions made by humans.
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.
The three UI researchers agree their new technique of detecting aerosols through clouds to make ground observations is likely to generate increasing interest, as the need to infer ground-air pollution levels and mitigate human hazards increases.
Paper co-authors also include space agency National Aeronautics and Space Administration Langley Research Center researcher Patrick Minnis and research support company Science Systems & Applications Incorporate researcher Kirk Ayers.
Edited by: Martin Zhuwakinyu© Reuse this Comment Guidelines
Other Environmental Studies News
High-tech computer applications for data management, mapping, modelling and imagery are assisting consultancy SRK Consulting in KwaZulu-Natal to present large amounts of data in a more accessible, visual format, allowing clients and stakeholders to quickly understand...
Recent Research Reports
Real Economy Year Book 2014 (PDF Report)
This edition drills down into the performance and outlook for a variety of sectors, including automotive, construction, electricity, transport, steel, water, coal, gold, iron-ore and platinum.
Real Economy Insight: Automotive 2014 (PDF Report)
This four-page brief covers key developments in the automotive industry over the past 12 months, including an overview of South Africa’s automotive market, trade figures, production and the policies influencing the sector.
Real Economy Insight: Construction 2014 (PDF Report)
This five-page brief covers key developments in the construction industry over the past 12 months. It provides an overview of the sector and includes details of employment in the sector, infrastructure and municipal spending, as well as insight into companies’...
Real Economy Insight: Electricity 2014 (PDF Report)
This five-page brief covers key developments in the electricity industry over the past 12 months, including details of State-owned power utility Eskom’s generation activities, funding and tariffs, independent power producers and prospects for the sector.
Real Economy Insight: Road and Rail 2014 (PDF Report)
This six-page brief covers key developments in the road and rail industries over the past 12 months, including details of South Africa’s road and rail network and prospects for both sectors.
Real Economy Insight: Steel 2014 (PDF Report)
This four-page brief covers key developments in the steel industry over the past 12 months. It provides an overview of the global and South African steel and stainless steel markets, South Africa’s major steel producers and events that have shaped these markets.
This Week's Magazine
Local aerospace company Denel Aerostructures (DAe), part of the State-owned Denel Group, has won a fourth contract to manufacture parts for the Airbus A400M military air transport and air-to-air refuelling aircraft. The new contract, which was won in an international...
Although CEO Mark McChlery and chief marketing officer Bob Skinstad likened themselves to children in a playground when taking on the task of “reengineering and repositioning” the Seartec brand, the “young, dynamic and enthusiastic guys” were like proud...
An increasing number of buyers, in both the new and used car markets, are opting for finance structures that lower their monthly repayments, says asset financing company WesBank. These include the use of large balloon payments (also known as residuals), as well as...
Tertiary education institutions can use search engine giant Google’s Chromebook to provide secure mobile end-point devices for students on which they can share documents, work collaboratively on documents and access education materials and applications being used...
Local ceiling and partition company Abbeycon has beaten global competition at the Saint-Gobain Gypsum International Trophy competition, which was held last month in Berlin, Germany.