PEPPERELL -- What is weather and what is climate change? How will a changing climate affect our communities?

These questions and more were discussed during "Climate Change in Pepperell" at the Prescott Grangein a talk given by Benjamin Brown-Steiner, a postdoctoral associate at the MIT Center for Global Change Science.

The recent increase in the number of ticks might be weather-related, said. But scientific models predict overall warming and changing precipitation patterns.

Those changes could affect many things, including pests, he said.

Weather is what you see when you go outside, he explained. It can vary, but a cold day is still just weather.

Climate change can only be viewed over time, using data sets to see trends. Then scientists use the data to predict what might happen over time, with different scenarios.

The answers scientists find are not exact. "We don't know what's going to happen," Brown-Steiner said.

All of the models show change, even models that take out human action, he said. But all of the models show the greatest change with human action.

Extreme weather events will increase in the region, he said. Since Pepperell has a history of floods, there could be more in the future.

The growing season will probably change, getting longer as temperatures increase, he said.

The best-case models show a warming trend of about two degree Celsius over time. That is enough for changes to the plants and animals that flourish in a given area.


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The worst-case scenarios, with high carbon emissions, show bigger changes. By 2099, the climate in New England could be like that of present-day South Carolina, he said.

The best way for people to slow down climate change is reduce the use of fossil fuels which release carbon dioxide and methane, which raise temperatures, into the atmosphere, Brown-Steiner said.

Because the oceans act like a giant heat sink, it takes hundreds of years to balance temperature changes. That makes it hard for scientists to "see that signal in the noise," he said.

In response to a question about agriculture, Brown-Steiner said that in addition to rising temperatures, the water table might go down. Despite more storms being predicted, the overall rainfall may decrease.

Sugar maples are stressed and moose calves further north are bleeding to death from tick infestations, the visitor from New Hampshire said. Looking at sensitive populations is a way to see change, Brown-Steiner said.

The learning aspect of the evening was especially appropriate because of the venue. The Prescott Grange building began life as a private school in 1834. It was the first home for Pepperell High School. The May 22 discussion was organized by the Pepperell Democratic Town Committee.

Follow Anne O'Connor on Twitter @a1oconnor.