Ambitious B.A. published in Nature

By Lokchi Lam

Alumna Jessica Wade-Murphy (Biology and Environmental Studies 2003) had her B.A. thesis published in Nature last Thursday, May 26.

The paper, written in collaboration with Jennifer McElwain of the Field Museum and Stephen Hesselbo of Oxford University, suggests that dramatic global warming occurred in the Jurassic Period after large amounts of coal were burnt by volcanic magma, causing mass extinction. It was selected by the magazine for its “relevance to global climate change,” being highly pertinent to the ongoing debate on global warming.

Wade-Murphy’s B.A. thesis consists of an impressive chain of scientific deduction. Using observations of the number of stoma (breathing holes) in 183-million-year-old fossil plants from a Baltic island, she estimated the carbon dioxide (CO2) levels of the period; these estimates in turn allow her to infer changes in temperature, since CO2, being one of the “greenhouse gases,” prevents the Earth from radiating heat.

Notably, there is a dramatic increase in CO2 levels during that period—up to over 1,000 parts-per-million, compared with today’s 380—which suggests sudden global warming.

Her data matches up with the existing theory, proposed by scientists in Norway, Hungary, and the United States, that major volcanic activity during the Jurassic burned large quantities of natural coal stores, releasing methane and CO2 into the atmosphere.

Remarkably, Wade-Murphy said, this reconstruction accurately parallels today’s situation, with many people burning large stores of coal, leading to an already observable increase in atmospheric carbon dioxide, and “who knows what consequences.”

Wade-Murphy founded the Green Campus Initiative RSO in her time at the U of C, and is also a Fulbright scholar. In retrospect, she’s happy she made a thoughtful choice for her B.A. project. “It’s a bit unbelievable, really,” she said. “I never expected the results to be so interesting for geologists and climate scientists.” She is currently continuing research at Utrecht University in the Netherlands.