Syracuse Sun

Severe flooding followed heavy rains in Cranford, New Jersey. Widespread climate change from global warming has devastating and lasting effects on human health, infrastructure, and food production. As temperatures rise, certain areas are dealing with intense droughts and water scarcity, while other regions are experiencing catastrophic rainfall and flooding. The eastern United States is one area that has seen a marked rise in torrential storms in recent years. A byproduct of this was the East Kentucky flood of 2022, which occurred when a storm swept through, dropping four inches of rain per hour, resulting in the tragic loss of 44 lives and the declaration of 13 counties as federal disaster areas.

As the eastern U.S. comes to grips with the changing climate, local and state governments depend on accurate rainfall predictions to help save lives and minimize property damage. But human-caused climate change makes it difficult to isolate processes in the atmosphere and ocean responsible for long-term trends in rainfall. This makes it especially challenging to predict rainfall changes on a local scale. A team of researchers from the University’s Department of Earth and Environmental Sciences (EES) in the College of Arts and Sciences (A&S) has been awarded a $547,000 grant from the National Science Foundation to investigate ancient climate data to help improve the accuracy of climate modeling and future rainfall predictions.

The project is led by principal investigator (PI) Tripti Bhattacharya, Thonis Family Professor in EES, and co-PI David Fastovich, a postdoctoral researcher in Bhattacharya’s Paleoclimate Dynamics Lab. Bhattacharya is a leading expert in organic geochemistry and climatology, which involves studying how atmospheric conditions have changed over time. Fastovich, who joined Bhattacharya’s lab at Syracuse in 2022, has particular interest in using the geologic record to better understand future global change.

“This project really brings together David’s and my expertise to tackle a climate question of strong relevance to the northeast U.S., including the Central New York region,” says Bhattacharya.

According to Fastovich, extreme rainfall in the eastern and central U.S. results from a “perfect storm” of conditions in the atmosphere, Gulf of Mexico, and Atlantic Ocean.

“When oceanic and atmospheric conditions are just right, air laden with moisture from the Gulf of Mexico is directed towards the central and eastern U.S. This air is then quickly lifted by atmospheric processes creating pockets of intense rainfall,” he explains. “We hypothesize that the relative importance of oceanic and atmospheric processes needed to create extreme rainfall are poorly approximated in climate models that are used to make predictions of the future.”

The team will take measurements of leaf waxes from lake sediments preserved since the last ice age and compare those results to climate models to identify why predictions of rainfall in the central and eastern U.S. are uncertain.

Their research will focus on the period from the Last Glacial Maximum (~20,000 years ago) to the Holocene (last ~12,000 years). During this time there was an increase in atmospheric carbon dioxide which led to ice sheet retreat and ocean heat transport variability—which refers to fluctuations in heat movement within oceans.

The leaf waxes that will be studied originate from five lakes across Ohio, Missouri, and Florida. Bhattacharya works with a gas chromatograph that allows her to quantify concentrations of leaf waxes stored within sediments.

“My lab measures leaf waxes but David’s unique expertise is helping us apply this technique in a new setting,” says Bhattacharya. “This grant is a great example of how postdoctoral scholars enrich research expertise here at Syracuse University.”

Fastovich notes his engagement with hands-on research using field-leading instrumentation was one reason he chose Syracuse.

“I was really drawn to expertise here,” he says. “Through this project we’re using sophisticated equipment to study leaf waxes which make up shiny layers on plants preventing them from drying out.”

The team will measure different proportions of hydrogen atoms from sediment cores to understand how rainfall changed over 18 millennia. With data collected they aim at developing hydroclimate reconstructions revealing physical processes like atmospheric circulation enabling understanding changes over time.

“Climate models struggle capturing historic hydroclimate as they overestimate precipitation along Atlantic coast while underestimating it Great Plains,” says Bhattacharya.“With precipitation amount predicted robustly increasing accurate models essential for policymakers making informed decisions.”

Fastovich emphasizes difficulty altering trajectory short stopping carbon emissions altogether making critical engaging improving model accuracy preparing future.

“The less carbon emitted less rainfall differs historical trends accustomed,” he says.“But important note eastern U.S locked some changes high levels preparing infrastructure imperative.”

Duncan Brown vice president for research notes Fastovich's contribution exemplifies significance postdoctoral scholars research mission Syracuse University establishing Office Postdoctoral Affairs providing centralized resources dedicated staff serving interests well-being postdocs fall 2023

“Professor Bhattacharya Dr.Fastovich award demonstrates important role postdocs play pursuing funding working research creative projects,” says Brown

To help more postdocs win funding Office Postdoctoral Affairs running series development sessions targeted starting next academic year