In 1787, U.S. Founding Father Thomas Jefferson wrote "Notes on the State of Virginia" and included five chapters relating to science.
Of its climate he wrote a note about warming: "From the year 1741 to 1769, an interval of twenty-eight years, there was no instance of fruit killed by the frost in the neighborhood of Monticello."
A short while later, Noah Webster, later famous for his dictionary, went after Jefferson, noting that thermometers, which Jefferson loved, were terrible ways to record data and his micro-climate observations didn't mean anything.