Courtesy of Judy Lloyd

From: Judy Lloyd
Veracruz, March 13, 2006

Aboard the Gulfstream G1 Airplane

Hi again-

I flew from Mexico City to Veracruz yesterday to see how the aircraft operation was going. Our airplane is the Grumman Gulfstream 1 (G1) operated by the United States Department of Energy. It’s a twin turbo-prop plane that carries five scientists along with lots of equipment to measure trace gases and particles of all sizes. We pull outside air into our instruments through small openings in the windows and nose. There’s an onboard computer where we can watch the flight track and the composition of the air in real time as we fly.

I am working on the G1 with Linda Bowerman, measuring the amount of peroxide in the air. That’s Linda in the picture, working on the plane with the peroxide analyzer we built in our laboratory. Peroxides are natural end products of chemistry that goes on in Earth's atmosphere, and are present in small quantities even in very clean air. In a warm moist climate with pollution from hydrocarbons, we expect to see lots of peroxides. They may be responsible for some of the haze we see during pollution episodes. So far, we haven’t observed more than the usual amount, but it has been pretty dry during our first few flights. We’ll keep looking, to be sure we understand the complicated chemistry of the atmosphere!


Photochemical smog

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