Indian Scientist's Aerial Technology to Evaluate Beijing's Pollution Curbs

by Tanya Thomas on Aug 11 2008 9:06 AM

Beijing’s abnormally high levels of air pollution has been discussed at length by world media thus coercing its government to meet the issue head-on. The government has imposed reductions in industrial activity to cut down on this glaring problem.

After the kick-off of the Beijing Olympics, scientists have decided to take advantage of the current situation in the Chinese capital. A team led by an Indian-origin scientist will use state-of-the-art technology to understand the atmosphere’s reactions when daily industrial emissions are reduced substantially in a heavily populated region.

For this purpose, scientists are conducting the "Cheju ABC Plume-Monsoon Experiment" (CAPMEX), which will include a series of flights by specially equipped unmanned aircraft known as autonomous unmanned aerial vehicles (AUAVs).

Developed at the Scripps Institution of Oceanography (SIO) in La Jolla, Calf, the aerial vehicles are employed with instruments that can measure smog and its effects on meteorological conditions.

The instruments will observe pollution transport patterns as Beijing enacts its "great shutdown" for the Summer Olympic Games. Thick smog often obscures the sky over Beijing and thus residents are frequently warned to stay indoors.

For the experiment, data-gathering flights will start from the South Korean island of Cheju, located about 1,165 kilometers (725 miles) southeast of Beijing. This island is in the projected path of pollution plumes that begin in various cities in China, including Beijing.

The scientist will then combine the information from the flights with the measurements by satellites and observatories on the ground that will track dust, soot and other pollution aerosols that travel from Beijing and other parts of China in so-called atmospheric brown clouds.

Thanks to the concern of Olympic organizers, the Chinese government, and the cooperation of the Korean government, we have a huge and unprecedented opportunity to observe a large reduction in everyday emissions from a region that's very industrially active," said atmospheric scientist V. Ramanathan of SIO, the lead investigator of CAPMEX.

"Ramanathan's earlier research on atmospheric brown clouds demonstrated their importance in the polluted regions of the atmosphere. CAPMEX takes this work an important step forward with new micro- and nano-sensor technologies. These technologies will provide new estimates of solar irradiance, aerosol-cloud interactions, climate forcing and important components of the biogeochemical cycles of the East Asian and western Pacific Ocean region," said Jay Fein, NSF program director for climate dynamics.

While satellite and ground observations began on August 1, the pre-inspection test flights will begin August 9, with the field campaign expected to run through September 30.

"Black carbon in soot is a major contributor to global warming. By determining the effects of soot reductions during the Olympics on atmospheric heating, we can gain much needed insights into the magnitude of future global warming," said Ramanathan.

AUAVs enable researchers to form dimensional profiles of clouds and other atmospheric masses at relatively low cost.

Miniaturized instruments on the aircraft measure a range of properties such as the quantity of soot and size of the aerosols upon which cloud droplets form.

The instruments also record variables such as temperature, humidity and the intensity of sunlight that permeates clouds and masses of smog.

For CAPMEX, photonics instruments will be added to the aircrafts' payloads to help calculate the specific contributions of various aerosols to atmospheric heating.