Jessica Tierney

Jessica E. Tierney,

Associate Professor,

UA Department of Geosciences

Wednesday, October 21, 2020,

2:30-3:30 pm,

an ASA Zoom Webinar*

Over the past 50 years the average global temperature, recorded since 1886, has increased at the fastest rate in all of recorded history. All but one of the 16 hottest years has occurred since 2000. Many scientists predict that average temperatures in the US could increase by up to 10 degrees over the next century if nothing is done to curb the greenhouse gas emissions that are responsible for the vast majority of the increase.

What difference will that make to human life here? There is a strong scientific consensus that earth’s rising temperatures are fueling longer, hotter heat waves, more frequent droughts, heavier rainfall and more powerful storms. Other effects are melting glaciers, severe water shortages, catastrophic wildfires, flooding caused by rising oceans, habitat disruptions leading to extinctions, and human maladies caused by air pollution, pathogens and insects.

Jessica Tierney is an Associate Professor at UA in the Department of Geosciences. She holds a Ph.D. in paleoclimatology and organic geochemistry from Brown University and heads a research team in molecular paleoclimatology at UA. Their focus is on studying past climate change via encoded fossil molecules, called biomarkers, preserved in sediments. This information tells us about the history of climate change on Earth and helps climate scientists predict future effects of climate change, in particular, global warming. She uses various tools to help her reconstruct climate deep into Earth’s geologic past. These tools include geochemistry, isotope analysis, climate models and statistics. She finds biomarkers produced by plants and microbes are also useful because environmental conditions like temperature and aridity are encoded in their molecular structure. Modern day samples of certain plants can be calibrated with the past biomarkers. The modern plants serve as proxies to help piece together the history of Earth’s climate.

In addition to her appointment as an associate professor at UA, Dr. Tierney has done research at Woods Hole Oceanographic Institution and Columbia University. She has co-authored 54 peer reviewed publications and is the recipient of many grants and awards.  

Written by Roxy Mitchem-Horn, Academy Village Volunteer

*To access the Zoom webinar, please write to 

Oct. 21: “The Sciences of Global Warming”