Humanity currently faces an undeniable climate crisis and imminent changes in Earth’s climate dynamics. Associate professor Sylvia Dee addresses the climate crisis by improving climate models and their physics to better understand weather patterns that affect all of us. Her passion for climate science is rooted in her concern about extreme weather and natural disasters associated with climate change driven by human activities.
“My work tries to generate a better understanding of the risks of global warming and climate change,” she explained. “How will atmospheric circulation and extreme rainfall events change in the 21st century? We should be prepared.”
Understanding fluctuations in Earth’s climate begins with better observations and models of major climate features like the water cycle and atmospheric temperature. Climate scientists use climate models to describe and simulate these phenomena.
“We write the equations governing the motion and thermodynamics of the atmosphere and the ocean into millions of lines of code,” Dee said. Scientists can predict climate by solving these systems of equations over specific timescales and time periods in what they call general circulation models (GCMs). Similar to how a weather forecasting model predicts this week’s chance of rain over a given town, GCMs predict rainfall patterns over decades for the entire country.
To better predict future climate, Dee improves GCMs by comparing simulations of past time periods with geological archives — data that can span centuries or even millennia.
“To understand the long-term behavior of the climate system, we have to use what we call paleoclimate proxies, which are historic records of climate conditions in things like glaciers and tree rings,” she said.
Dee uses those proxies to obtain information about atmospheric and ocean temperatures, as well as rainfall patterns, encoded in their isotopic conformation. For instance, the amount of oxygen-18 and deuterium (less abundant isotopes of oxygen and hydrogen) in samples of ice or corals provides a “fingerprint” for fluctuations in temperature and rainfall.
“One thing we are interested in is how El Niño–Southern Oscillation will change with global warming, and we can study that by looking into the past during times that were relatively warmer or colder than today, like the last ice age,” she added.
Dee’s lab also works on the risk of severe weather and its impacts on human health. “The primary thing we’re working on is the impact of extreme heat, which is obviously a problem in Houston,” she said.
Extreme temperatures and major weather events like hurricanes can sometimes lead to higher rates of vector-borne and water-borne diseases by impacting the populations of mosquitoes and bacteria. By developing forecast models for seasons of high heat or rainfall, Dee seeks to mitigate the risk of such diseases using early warning systems and public health policy.
“For example, we are currently working with Rice360 and NEST360 to examine maternal health and preterm labor outcomes in African hospitals subjected to high heat events,” she said. Preparing for those harsh, hot conditions starts by understanding and predicting the climate dynamics causing them.
Dee is passionate about helping the public understand the environmental problems we face and the risks of not solving them. By providing estimates of higher rainfall and temperatures, her work can inform public policy and motivate environmental restoration. This better prepares the population for natural disasters that affect us all.
When the picture of Earth’s climate future seems bleak, Dee reassures her students with a quote from Marie Curie: “Nothing in life is to be feared, it is only to be understood; now is the time to understand more, so that we may fear less.”
—Andrés B. Sánchez-Alvarado