The Delaware River could rise well more than a foot by midcentury, and temperatures could heat up nearly 6 degrees, accompanied by a rise in extreme heat days, according to a new report that localized data to create a snapshot of local climate change in Philadelphia.

The report came from a coalition formed in response to rallies and a petition by Drexel University students in 2019 imploring the school to take action on climate change.

After the student action, representatives from the city of Philadelphia, Drexel University, the Delaware Valley Regional Planning Commission, and the Academy of Natural Sciences of Drexel University formed the Climate Resilience Research Agenda. The group released a report on the potential impacts of climate change Wednesday during Green Building United's annual sustainability symposium, which was held this year at Drexel.

Some areas will be impacted more than others, said Franco Montalto, a Drexel engineering professor who coedited the report. For example, communities such as Philadelphia's Eastwick section are already vulnerable to flooding. Other parts of the city are more affected by heat waves.

Montalto said changing patterns could also impact the urban forest, wetlands, and floodplains.

"The groups raised a bunch of questions about the built environment, about transportation systems about energy systems, buildings, and what we need to know to make those systems continue to function despite climate change," he said.

The city is already seeing an increase in precipitation, the report noted, and six of the 10 wettest years on record have occurred since 1990. Average annual precipitation has increased over the last century, and variability of amounts has become more pronounced.

For the report, the Consortium for Climate Risk in the Urban Northeast extrapolated climate modeling data compiled by the Intergovernmental Panel on Climate Change to form local models. The United Nations panel has been compiling climate change data for more than 30 years. It released its sixth assessment last year with updated data.

Projections call for an increase of 5% to 12% in precipitation by the 2050s, using a baseline period of 1981 to 2010. Precipitation is expected increase by 8% to 16% by the 2080s. Rangers could be higher or lower depending on whether carbon emissions increase, decrease, or stay the same.

The report acknowledges that the frequency and intensity of rainstorms are harder to project. But they noted the big impact of Hurricane Isaias that walloped Southwest Philadelphia in August 2020 and the remnants of Hurricane Ida that flooded the Vine Street Expressway when the Schuylkill overflowed its banks in September 2021.

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