Monday, April 17, 2006

Scripps-led Project Achieves Milestone in
Analyzing Pollutants Dimming the Atmosphere

Technology behind unmanned aerial vehicles proves successful for flying beneath, above and through clouds to trace pollution particles

Scripps Institution of Oceanography / University of California, San Diego

NOTE:

V. RAMANATHAN WILL APPEAR ON PUBLIC BROADCASTING SERVICE'S (PBS) NOVA PROGRAM "DIMMING THE SUN" ON TUESDAY, APRIL 18, 2006, AT 8 P.M. (www.pbs.org/wgbh/nova/sun)



A scientific research consortium led by Scripps Institution of Oceanography at the University of California, San Diego, has reached an important milestone in the tracking of pollutants responsible for dimming Earth's atmosphere.


Scripps Oceanography scientist Veerabhadran Ramanathan reported that instrument-bearing autonomous unmanned aerial vehicles (AUAVs) completed 18 successful data-gathering missions in pollution-filled skies over the Indian Ocean in the vicinity of the Maldives, an island chain nation south of India. During the Maldives AUAV Campaign (MAC), groupings of three aircraft flew in synchronous vertical formation, which allowed onboard instruments to observe conditions below, inside and above clouds simultaneously. Researchers hope the data produced during the flights will reveal in unprecedented detail how pollution particles cause dimining and contribute to the formation of clouds which amplify the dimming caused by the pollution.

Stacked flights with manned aircraft have been attempted, but rarely. The difficulty and cost of assembling and coordinating three similar aircraft have prevented the sort of repeated measurements required to sample clouds adequately.

"Based on MAC's success it is possible that in five years, hundreds of lightweight AUAVs will be documenting how human beings are polluting the planet and hopefully provide an early warning system for potential environmental disasters in the future," said Ramanathan.

The skies over the Indian Ocean visibly bear the imprint of human activities in South Asia, frequently in the coverage of what are termed atmospheric brown clouds, particulate-laden haze and cumulus clouds that frequently blanket the region. The role that dust and aerosols from industrial, urban and agricultural emissions play in creating such a brown haze is an important variable to researchers who study anthropogenic climate change, specifically how human activities could be changing the planet's albedo, or reflectivity. Cloud cover cools Earth's surface by reflecting solar radiation back into space. In recent years, researchers have come to realize that pollution in the atmosphere and the dimming and cooling it causes could actually be leading scientists to underestimate the true magnitude of global-warming trends observed in recent decades.

Ramanathan has led a consortium of academic and industrial partners in the development of aircraft and integrating them with miniaturized instruments that can obtain aerosol-cloud-solar radiation data in remote regions once considered unobtainable: multi-dimensional portraits of clouds created in polluted environments over periods of several hours. The "Manta" AUAVs, constructed by Tucson, Ariz. firm Advanced Ceramics Research (ACR), represent a feat of miniaturization (an ACR flight team supported Ramanathan's research by flying more than 100 hours in gathering the atmospheric data).

Each AUAV bears an instrument package that weighs less than five kilograms (11 pounds). The packages developed by the Scripps team include sensors for measuring solar radiation, cloud-drop size and concentrations, particle size and concentrations, turbulence, humidities and temperatures.

Flights took place between March 6 and March 31, taking off from an airport on the island of Hanimaadhoo in the Maldives. Each AUAV tracked a separate component of brown cloud formation. The lowest, flying beneath the cloud, quantified the input of pollution particles and measured quantities of light that penetrated the clouds. The aircraft flying through the cloud measured the cloud's response to the introduction of particles. The aircraft flying above the cloud measured the amount of sunlight reflected by the clouds into space and the export of particles out of the clouds.

"MAC has demonstrated that lightweight AUAVs and their miniaturized instruments are an effective and inexpensive means of simultaneously sampling clouds in polluted environments from within and from all sides," said Jay Fein, program director in the National Science Foundation's Division of Atmospheric Sciences. "They will serve as critically important additions to our atmospheric measurement capability in addressing one of the major outstanding issues in climate change science: How does pollution affect cloud microphysical and radiative processes in the context of weather and climate?"

"We are excited about being involved in the study of atmospheric brown cloud affects using cutting edge flight control software we developed in our unmanned aerial vehicles," said Anthony Mulligan, CEO of Advanced Ceramics Research. "Our employees are proud to have provided Scripps scientists a way to further their research and look forward to continue to provide them a low-cost, effective way to gather additional information."

The research was funded by the National Science Foundation, the National Oceanic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), the G. Unger Vetlesen Foundation and the Alderson Foundation. The researchers also wish to acknowledge the support of the United Nations Environmental Program and the support and cooperation of the Republic of Maldives.

More details of the campaign and Project Atmospheric Brown Clouds, of which MAC is a component, are available at www-c4.ucsd.edu/ProjectABC.

# # #

Project ABC: www-c4.ucsd.edu/ProjectABC/

Scripps Institution of Oceanography: scripps.ucsd.edu

Scripps News:scrippsnews.ucsd.edu

Note to broadcast and cable producers: UCSD provides an on-campus satellite uplink facility for live or pre-recorded television interviews. Please phone or e-mail the media contact listed above to arrange an interview.

# # #

Note to broadcast and cable producers: University of California, San Diego provides an on-campus satellite uplink facility for live or pre-recorded television interviews. Please phone or e-mail the media contact listed above to arrange an interview.

Scripps Institution of Oceanography, at University of California, San Diego, is one of the oldest, largest and most important centers for global science research and education in the world. The National Research Council has ranked Scripps first in faculty quality among oceanography programs nationwide. Now in its second century of discovery, the scientific scope of the institution has grown to include biological, physical, chemical, geological, geophysical and atmospheric studies of the earth as a system. Hundreds of research programs covering a wide range of scientific areas are under way today in 65 countries. The institution has a staff of about 1,300, and annual expenditures of approximately $155 million from federal, state and private sources. Scripps operates one of the largest U.S. academic fleets with four oceanographic research ships and one research platform for worldwide exploration.

The Maldives AUAV Campaign

AUAV technology used to study pollution

The future of AUAVs and environmental studies

• Mario Aguilera or
  Cindy Clark
• Phone: 858.534.3624
  scrippsnews@ucsd.edu

• Project ABC
• Scripps Home
• ScrippsNews Home

© Scripps Institution of Oceanography, University of California, San Diego 2010. All Rights Reserved