NEPA climate to mirror Philly in 50 years

By mid-century, the climate of Scranton and Wilkes-Barre will be more like Philadelphia’s if the world stays on its current course of greenhouse gas emissions, scientists estimate.

Published: September 3, 2015 

Pennsylvania as a whole has already warmed 1.8 degrees Fahrenheit over the past 110 years, when federal records began, and has seen a 10 percent increase in average annual precipitation.

This trend is predicted to continue, with average annual temperatures in Scranton and Wilkes-Barre projected to warm another 5 or 6 degrees Fahrenheit by 2041 through 2070, with a 5 to 10 percent increase in precipitation.

The region’s future climate will be akin to Philadelphia or Wilmington, Delaware, said Penn State meteorology graduate student Andrew Ross, one of the authors of a detailed report released last week. The state Climate Change Act of 2008 requires the state Department of Environmental Protection to commission regular updates on the state’s climate. This was the second update to the original 2009 assessment.

“The scientific data is clear: climate change is happening and there will be impacts to Pennsylvania,” said Penn State professor and Environmental and Natural Resources Institute director James Shortle, Ph.D., the lead researcher. “The effects of climate change will be felt across all parts of Pennsylvania. Agriculture, human health, water quality, energy, even outdoor recreation will be affected.”

Researchers mapped the state’s future climate using a set of computer models that are becoming increasingly accurate and detailed, said Penn State oceanography professor Raymond Najjar, Ph.D., who has worked on multiple drafts of the report.

“Numerous studies have shown how each generation of climate models does a better job at simulating a variety of different metrics, like the overall patterns of surface temperature, precipitation and pressure,” he said.

Yet, the central conclusions have stayed the same, said Shortle, who led the first state assessment efforts in 2009.

“The major conclusions about climate change from the 2009 report to the current report aren’t that startlingly different,” he said. “Generally we see Pennsylvania becoming a warmer and wetter place.”

The change will bring a host of problems and a few opportunities.

“I do believe that the credibility of climate science means that you can’t always be alarmist,” Shortle said. “You do have to recognize positives as well as the negatives, and I think it’s important to keep relative risk in mind.”

For example, dairy farmers may face lower milk production from heat-stressed cows while forage crops improve.

Warming will increase demand for Pennsylvania energy, especially for electric power during hotter months.

Beyond 2050, ski resorts in Pennsylvania will not be economically viable, but warm-weather sports could maintain longer seasons.

For human health, heat-related deaths will increase as cold-related deaths will decline. Warming could also affect insect-borne diseases like Lyme disease or West Nile Virus, though scientists are not sure exactly how.

Foresters should also prepare for tree species ranges shifting northward, with some species declining in marginal habitat. Yet, warmer, wetter weather could boot forest growth as a whole.

Flooding is the natural disaster expected to pose the most severe threat in a warmer Pennsylvania. Making communities more flood resilient should be a high priority, the report states.

Overall, Pennsylvania may not fare as badly as other parts of the U.S.

“If you’re in a place experiencing climate change, Pennsylvania is a good a place to be,” Shortle said. “We won’t have, for example, the sea level rise that other places will be experiencing. We’re not going to be facing severe drought.