“My focus is the tiny particles that float in the air, like sea salt, smoke and wind blown minerals, and how trace pollutants might chemically change these particles and affect cloud formation and the climate.”

Hinrichs explains that these floating particles, called aerosols, serve as nuclei for water vapor. They create the medium on which clouds grow, and as clouds grow, they block sunlight from heating the earth. In effect, aerosols have a cooling effect on the earth. But what if air pollutants like ozone and nitrogen dioxide, which also cling to aerosols, hinder water vapor’s ability to form clouds? We’d have fewer clouds and less cooling to offset the warming caused by greenhouse gases.

At this point it’s not well understood exactly what pollutant gases like ozone and nitrogen dioxide do to aerosols. That’s why the National Science Foundation (NSF) recently awarded Hinrichs a $350,000, three-year grant to study the effects and help further the understanding of clouds, pollution and climate change. The funding is Drew’s first NSF Research at Under graduate Institutions grant in chemistry.

As part of the grant, Hinrichs and his undergraduate research assistants are busy creating model atmospheres in the laboratory and testing aerosols and pollutants under a wide range of temperatures, humidity, pressures and other conditions. In the process, his students become adept at handling liquid nitrogen at -320º Fahrenheit, infrared spectrometers and other materials and equipment as they create, test and document the model atmospheres. So far the results are surprising.

“The deeper we get into it, the more we realize how complex the atmosphere is,” he says. “If you put something into the atmosphere, but some other chemical is present or absent, you may get a completely unexpected result.”

Hinrichs’ fascination with science has deep roots: His mom was an eighth-grade science teacher in his school. Even though she gave him an A when he took her course, he insists there was no nepotism. Hinrichs laughs, “I’m sure I earned it.”

Nonetheless, having a mom at home preparing science demonstrations certainly didn’t stifle his aptitude. One of his vivid scientific memories, at about age 10, was watching his mom experiment with flying carbon paper. “We were together in the laundry room, and she had a piece of carbon paper, which she lit on fire at the top. Convection currents lifted the whole thing into the air. It seems counterintuitive to light it on the top, but it worked.” Then he jokes, “Perhaps NASA has been lighting its rockets on the wrong end.”

There was plenty of convection in Bethlehem, Pa., where Hinrichs earned his bachelor’s in chemistry at Moravian College in 1996. “I remember walking along the river across from the steel mills and watching big flames and smoke coming out of the stacks,” he says. “I’m not sure I made the connection between chemistry and the atmosphere at that point. It really came together at Cornell as I worked on my Ph.D. and learned a lot of interesting things about sunlight and photochemistry. When I left there I thought I needed to do science that I enjoyed and relate it to something I care about. And that’s how I became interested in the chemistry of the atmosphere. It all ties back to my appreciation of nature.”

Today, Hinrichs lives in Morris Plains, N.J., with his wife and two children, and he’s already nurturing an appreciation of science in his 4-year-old daughter. “She especially likes when I make liquid-nitrogen ice cream,” he says. “You just take milk, sugar and vanilla, pour in the liquid nitrogen, stir and it freezes.”

Hinrichs chuckles. “Of course she likes anything to do with ice cream.”