New Faculty Member Brings Broad Range of Interests to AOES

Dr. Natalie Burls joined the faculty of AOES in Spring 2015 from her position as a postdoctoral associate at Yale University Dept of Geology and Geophysics. Dr. Burls, who comes from South Africa, received her PhD, MSc, and BSc at University of Cape Town, where she studied atmospheric science and physical oceanography and received awards at 3 conferences for best student presentation. Dr. Burls has also joined the scientific staff of COLA.

Dr. Burls and a friendly grouper off the coast of Ponta Do Oura, Mozambique.

Dr. Burls brings a broad range of climate-related interests to the department. She studies the fluid dynamics of the atmosphere and ocean, which determine wind and ocean current variations such as the El Nino phenomenon in the tropical Pacific and an analogous mode in the tropical Atlantic. Her studies of tropical climate led her to investigate the role of clouds in modifying the amount of sunshine falling on the sea surface there. These studies, in turn, have helped spark an interest in past climates, such as the Pliocene Epoch (about 2.5 to 5 million years ago). The Pliocene was a warm period which may provide insight into future changes under global warming.

Dr. Burls contributed lectures to AOES geologist Linda Hinnov’s Paleoceanography class Spring semester and will be teaching atmospheric dynamics next year. She has acquired and assembled a rotating tank to create laboratory demonstrations for dynamics and other classes.

An exchange with Dr. Burls (edited for brevity):

What are the challenges and benefits of trying to get expertise over such a broad range of different, technically difficult, subjects?

The exciting and unanswered questions in climate dynamics lie on the edges of our discipline, however we must avoid becoming a jack of all trades and a master of none. Whenever possible, we team up with experts from other disciplines and leverage their expertise.

What question about the climate would you most like to be able to answer?

The biggest question on my mind right now is: What role did changes in cloud… reflectivity, play in maintaining the really warm periods we know existed in Earth’s history? This is a really hard question to answer particularly because no proxy for past cloud changes currently exists. Contemporary work on ocean dynamics and coupled ocean-atmosphere interactions keeps pointing back to just how important it is to understand and correctly reproduce cloud radiative forcing and feedbacks.

Could you talk a bit about your plans for the new rotating tank?

The effects of Earth’s rotation on atmospheric and oceanic circulation can seem so abstract when you are sitting in a classroom observing derivations on a chalkboard. The rotating tank will allow GMU… students to witness first-hand the amazing phenomena that arise due to Earth’s rotation.

Geophysical fluid dynamics tell us that the “water going down the drain the other way in the southern hemisphere” is a myth. As a South African have you ever checked this yourself?

I made a point of watching water draining out of our kitchen sink after doing the evening dishes – sometimes it drained out clockwise but other times anti-clockwise. I thought perhaps I was doing something wrong…. until college, where we learned that, relative to other forces acting on the water as it drains out of the sink, the effect of Earth’s rotation is negligible. With the theory confirming my observations I can attest to it being a myth, the effects of Earth’s rotation only take hold on much larger spatial and temporal scales.