CWU Chemistry Professor Piecing Together Global Climate Change Puzzle

September 28, 2009

ELLENSBURG, Wash. — Understanding the full scope of global climate change is like trying to piece together a gigantic, detailed puzzle without having the box’s handy picture as a guide. It takes determination, patience and a team of people who not only excel at every science, but who also share their research with each other, enabling the pieces to become a complete concept.

One piece of that puzzle is being examined at Central Washington University by associate chemistry Professor Anne Johansen. With the help of two National Science Foundation (NSF) grants equaling more than $500,000, Johansen has dedicated seven years and counting to the study of airborne iron particles, their effect on the oceans’ phytoplankton, and how those effects impact the earth’s climate. In August she returned from a yearlong sabbatical where she worked with a German scientist collecting data for her study.

It may sound insignificant — the goings-on of microscopic plant life. However, considering phytoplankton produces more than half the earth’s oxygen, takes in huge amounts of carbon dioxide for photosynthesis, and serves as the ocean’s base food web, the role these invisible, floating plants play is critical in maintaining earth’s fragile balance.

“It’s a very complex system,” Johansen says. “Phytoplankton is an essential component of earth’s equilibrium. If even one thing is off, it can make a huge difference in terms of weather, long-term climate and marine life.”

So when the phytoplankton’s food source — sunlight, water and minerals — is unbalanced, everything’s unbalanced. Phytoplankton, found in oceans, seas, and lakes, collects large and small nutritional minerals, such as the macronutrients solicic acid, phosphate and nitrate. It also collects the micronutrient, iron — a crucial ingredient. Some scientists believe in the southern area of the Pacific Ocean, iron levels are low.

Delivered in the form of dust, iron travels across the ocean, feeding the phytoplankton. But the more miles it travels, the more it disperses. In Johansen’s study, she has noted that when iron levels are low, the phytoplankton emit a gas which may actually be contributing to the earth’s greenhouses gasses; however this has yet to be proven.

“If the phytoplankton is iron-starved, it begins to emit a gas which can chemically transform our atmosphere,” Johansen says. “Reversely, if iron levels increase due to human causes, it can rapidly increase the phytoplankton’s growth, which can also be detrimental. So far, iron levels do not seem to be increasing thanks pollution control efforts.”

Scientists consider the increase and decrease of phytoplankton as a strong indicator of environmental changes. Why and how it changes, and what those changes mean exactly, still has yet to be fully understood.

To learn more about iron levels in the air, Johansen, along with CWU graduate students, have spent countless hours aboard ships, collecting air samples throughout different areas of the Pacific Ocean. It’s a fun job that allows her to get outside while studying, she says. And it’s great experience for graduate students because they get to learn the complex and detail-focused job of collecting and preserving lab samples.

Lindsey Shank — one of those graduate students and now an oceanography doctoral student at the University of Hawaii-Manoa and originally from Wenatchee, Washington — spent a lot of time on the cruises with Johansen collecting samples that were then taken back to CWU’s campus for examination.

“My experiences in Dr. Johansen’s lab definitely increased my maturity as a scientist and opened my eyes to the field of oceanography,” Shank says. “I learned what it was like to be a functioning member of an interdisciplinary field campaign and collaborate with groups of scientists from the fields of physics, chemistry, oceanography and atmospheric sciences.”

Back on campus, undergraduate chemistry students spend a lot of time making air samples with different iron levels in order to continue the study.

“It’s a really exciting project, with its field and lab work, and it’s great that it can involve students on so many levels,” Johansen says. “So far I’ve had about 15 students involved in the project since it started in 2002.”

The graduate students who accompany Johansen on trips assist her with collecting air samples over a 24-hour period. It’s a labor-intensive process that requires great attention to detail.

Johansen and her students use a special machine, known as a high-volume aerosol collector, which separates minerals by size and puts them in different chambers. It collects 800 liters of air per minute through a pump-vacuum system.

“We have to be very careful not to contaminate the samples. It takes months to even prepare for these trips,” Johansen says. “Once the samples are collected, they are put on Petri dishes and kept in a freezer.”

Johansen credits the air sample-collecting machine as part of the reason for why she received the two NSF grants. The machines are no longer in production and not many scientists have one.

Johansen’s first grant was awarded to her in 2002 for $375,000. The second one was given to her in December for $135,500. For the next two years she, along with CWU students, will continue the study.

She’s also working on three other projects that have involved students, including examining the chemistry and subsequent faults in local wines, studying the ultrafine particulates from automotive emissions and their effects on human health, and a long-term study involving the chemistry of precipitation and high-elevation lakes in Mt. Rainier National Park.

For more information on chemistry at CWU, visit www.cwu.edu/~chem.

Media Contact: Liz Bryson, CWU Public Relations & Marketing, 509-963-2714, brysone@cwu.edu

Central Washington University is a master's degree-granting institution with approximately 10,000 students and 1,500 faculty and staff. More than 160 undergraduate and master's degrees are offered. Founded in 1891, the Ellensburg campus is located in the heart of Washington State, nestled between the Cascade Mountains and the Columbia River. Since 1975, CWU has served the needs of placebound students at six university centers throughout the state. CWU is an AA/EEO Title IX Institution.