Jefferson’s weather observations contribute to statewide climate assessment

CHARLOTTESVILLE, Va. (WVIR) — Climate is changing in Virginia and scientists say the evidence goes back hundreds of years.

A new statewide assessment uses old handwritten weather notes from Thomas Jefferson and combines them with modern science to show where Virginia’s climate is heading.

“What we found that was interesting, or what this data can tell us, is the climate, not just globally, but throughout the whole Virginia region, has changed drastically from the 1700’s to today,” said Luis Ortiz, Assistant Professor of Climate Applications at George Mason University’s Department of Atmospheric, Oceanic, and Earth Sciences.

Ortiz and a team of researchers just released Virginia’s first statewide climate assessment, pulling together decades of studies and even centuries-old weather notes.

A big part of that history comes from Thomas Jefferson, who kept detailed temperature logs at Monticello for more than 20 years.

“For that reason, most of the data you see that he collected was temperatures, which was the most reliable instrumentation we had back then,” Ortiz said. “We have thermometers of course, but we also have, surface level pressure, atmospheric pressure, a lot of that is based on observations that we take.”

That contrast, simple handwritten readings versus modern sensors across the state, helps show how much the Commonwealth’s climate has shifted.

“What we did was almost like taking a diagnostic of what’s happening,” Ortiz said. “Others might take that information and make some prescriptions… to protect businesses, livelihoods, et cetera.”

The assessment highlights warmer temperatures, heavier rainfall and more frequent flooding. Which make things harder on Virginians, farmers and infrastructure.

Ortiz says some early warming was detectable in Jefferson’s era, but for a very different reason.

“He might actually have seen a rise in temperatures as we were climbing out of that cold period of time, the greenhouse gas effect and how that’s been driving larger and larger increases of temperatures that we have been observing from the past, over 150 years ago,” Ortiz said.

Virginia does not have observations for all of Virginia from the 1700’s but even small bits of Jefferson’s data, still matter, and researchers are not stopping with this report.

“We are right now in the process of conceptualizing the next iteration,” Ortiz said. “It’s the first one because we want to keep making more of them.”

In the report, it is noted these changes have a big domino effect for future years.

Even as far as higher utility bills, disease and population displacement.

By 2050 coastal Virginia could face risks of sea-levels rising.

For the assessment you can click here.

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